Intelligent electric control adjustable tail wing adaptive control method and system

Abstract

This invention discloses an intelligent electronically controlled adjustable rear wing adaptive control method and system, relating to the field of adaptive control technology. The method includes: generating a set of operating condition trend parameters based on vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data; performing a rear wing state switching buffer determination based on the operating condition trend parameter set; generating a target state angle of attack and a target rear wing angle of attack sequence; and generating an adaptively vibration-damping corrected rear wing execution drive signal based on the target rear wing angle of attack sequence and the actual rear wing angle feedback, and outputting it to the rear wing actuator. This invention achieves stable switching of the rear wing state and continuous adjustment of the angle of attack, suppresses frequent jumps, execution jitter, and attitude disturbances under critical operating conditions, and improves the stability and tracking accuracy of the rear wing control.

Description

Technical Field

[0001] This invention relates to the field of adaptive control technology, and more specifically, to an intelligent electronically controlled adjustable tail fin adaptive control method and system. Background Technology

[0002] With the continuous development of high-performance passenger vehicles, racing platforms, and intelligent vehicles with active aerodynamic adjustment capabilities, adjustable rear wings have gradually evolved into active actuators capable of participating in longitudinal drag reduction, lateral stability enhancement, and attitude coordination. By electronically adjusting the angle of attack of the rear wing, air resistance can be reduced during straight-line acceleration, and rear-end adhesion and driving stability can be improved during cornering, steady-state cornering, and cornering exit. Therefore, adjustable rear wing control technology has become an important technical means to improve vehicle dynamic performance and handling quality. In existing technologies, common solutions typically use vehicle speed, braking signals, steering signals, or preset driving modes to perform graded control of the rear wing attitude. Some solutions use fixed thresholds to trigger rear wing state switching, some use preset angle of attack levels or discrete control logic to adjust the position of the rear wing actuator, and some solutions introduce angle feedback to correct deviations in the actual position of the rear wing.

[0003] However, during dynamic transitions such as a vehicle moving from straight-line driving into a curve, from braking to steady-state cornering, and from cornering to acceleration out of a curve, vehicle speed, braking input, steering input, and spoiler feedback typically exhibit continuous changes, short-term fluctuations, and multi-source coupling. Existing technologies mostly rely on a single sampled value or a single threshold to directly determine the spoiler's state, lacking mechanisms for time-window processing, trend analysis, and stability assessment of multi-source operating data. Therefore, it is difficult to distinguish between stable operating condition changes and instantaneous disturbances near critical boundaries. When vehicle operating parameters fluctuate slightly around the threshold, the spoiler control logic tends to frequently switch between angle-of-attack stabilization and angle-of-attack drag reduction states, leading to abrupt changes in spoiler angle of attack, aerodynamic torque, and vehicle attitude disturbances, weakening the consistency and predictability of the vehicle's dynamic response.

[0004] Meanwhile, existing technologies typically output discrete angle commands directly or employ simple position tracking methods after tail fin state switching, lacking continuous angle-of-attack generation and vibration suppression control mechanisms during execution. This leads to overshoot, yaw, local oscillations, and repetitive actions in the tail fin actuator when approaching the target angle. Especially under the combined effects of wind load disturbances, mechanical clearances, execution hysteresis, and feedback noise, repeated corrections easily occur between the actual tail fin angle and the target angle, increasing the burden and wear on the actuator, and reducing the target angle-of-attack tracking accuracy and tail fin control stability. Therefore, how to construct an intelligent electronically controlled adjustable tail fin adaptive control scheme that can identify operating conditions based on multi-source operating states, stably complete tail fin state switching, and suppress overshoot, yaw, and chattering during the execution phase has become a pressing technical problem to be solved in this field. Summary of the Invention

[0005] To overcome the aforementioned deficiencies of the prior art and achieve the above objectives, the present invention provides the following technical solution: an intelligent electronically controlled adjustable tail fin adaptive control method, comprising:

[0006] Based on vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data, a set of operating condition trend parameters is generated.

[0007] Based on the set of operating condition trend parameters, the angle of attack stabilization judgment value and the angle of attack drag reduction judgment value are generated. A tail fin state switching buffer judgment system is constructed. The system performs an out-of-bounds judgment based on the current tail fin state record value. Combined with the cumulative duration of entering the corresponding state and the shortest holding time, the system outputs the tail fin target state switching command or maintains the current tail fin state unchanged.

[0008] Based on the tail fin target state switching command, the current tail fin state record value, the working condition trend parameter set and the actual tail fin angle data, the current adjustment direction is determined, the corresponding target state angle of attack and the current adjustment step size are generated, the corresponding angle of attack change trajectory is called to generate the current target tail fin angle of attack in each sampling period, and the target tail fin angle of attack sequence is constructed and output after executing the change amount constraint;

[0009] The target tail fin angle of attack sequence and the actual tail fin angle data are read, the angle deviation between the current target tail fin angle of attack and the current actual tail fin angle is calculated, a tail fin execution drive signal is generated based on the angle deviation, and an adaptive vibration suppression correction is performed on the tail fin execution drive signal according to the actual tail fin angle change rate, the number of reverse corrections and the tail fin attitude fluctuation amplitude, and the corrected tail fin execution drive signal is output to the tail fin actuator.

[0010] Furthermore, the calculation methods for angle deviation, actual tail fin angle change rate, number of reverse corrections, and tail fin attitude fluctuation amplitude include:

[0011] Read the current target tail fin angle of attack and the current actual tail fin angle corresponding to the current sampling period, and subtract the current actual tail fin angle from the current target tail fin angle of attack to obtain the current angle deviation;

[0012] Write the current actual tail fin angle into the actual tail fin angle buffer, and write the current angle deviation into the angle deviation buffer;

[0013] The rate of change of the actual tail fin angle is calculated based on the continuous actual tail fin angles in the actual tail fin angle buffer area. The number of reverse corrections is counted based on the continuous angle deviations in the angle deviation buffer area. The tail fin attitude fluctuation amplitude is calculated based on the continuous actual tail fin angles in the actual tail fin angle buffer area.

[0014] Furthermore, the method for generating the tail fin drive signal and performing adaptive vibration damping correction includes:

[0015] The corresponding execution gain is selected based on the absolute value of the current angle deviation, and the current angle deviation is multiplied by the current execution gain to generate the initial tail fin execution drive signal;

[0016] Determine if any of the following risks exist: the risk of excessively rapid change in the actual angle of the tail fin exceeding the execution angular velocity threshold; the risk of frequent reverse corrections where the reverse correction count is greater than or equal to the reverse correction threshold; or the risk of significant attitude fluctuations where the tail fin attitude fluctuation amplitude is greater than or equal to the attitude fluctuation threshold.

[0017] If present, reduce the current execution gain and regenerate the corrected drive quantity based on the reduced current execution gain and the current angle deviation; compare the drive change between the corrected drive quantity and the previous tail fin execution drive signal, and when the absolute value of the drive change is greater than the upper limit of the drive change, apply a change limit to the corrected drive quantity; use the corrected drive quantity after change limit as the current candidate tail fin execution drive signal.

[0018] If it does not exist, the initial tail fin drive signal will be used as the current candidate tail fin drive signal.

[0019] Furthermore, the method for outputting the tail fin actuation drive signal to the tail fin actuator includes:

[0020] When the absolute value of the current angle deviation is not greater than the execution convergence threshold, the absolute value of the actual angle change rate of the tail fin is not greater than the execution angular velocity threshold, and the tail fin attitude fluctuation amplitude is less than the attitude fluctuation threshold, the stable holding drive value will be output as the tail fin execution drive signal to the tail fin actuator.

[0021] When the absolute value of the current angle deviation is greater than the execution convergence threshold, or the absolute value of the actual angle change rate of the tail fin is greater than the execution angular velocity threshold, or the tail fin attitude fluctuation amplitude is not less than the attitude fluctuation threshold, the current candidate tail fin execution drive signal is output as the tail fin execution drive signal to the tail fin actuator.

[0022] Furthermore, the current method for generating the adjustment direction includes:

[0023] Read the tail fin target status switching command and the current tail fin status record value;

[0024] When the tail fin target state switching command is to switch to angle of attack stabilization state and the current tail fin state record value is angle of attack drag reduction state, the current adjustment direction is determined to be the stabilization adjustment direction;

[0025] When the tail fin target state switching command is to switch to angle of attack drag reduction state and the current tail fin state record value is angle of attack stabilization state, the current adjustment direction is determined to be the drag reduction adjustment direction.

[0026] When the tail fin target state switching command is to maintain the current tail fin state and the current tail fin state record value is the angle of attack stabilization state, the current adjustment direction is determined to be the stabilization maintenance direction.

[0027] When the tail fin target state switching command is to maintain the current tail fin state and the current tail fin state record value is the angle of attack drag reduction state, the current adjustment direction is determined to be the drag reduction maintenance direction.

[0028] Furthermore, the methods for generating the target state angle of attack and the current adjustment step size include:

[0029] When the current adjustment direction is the stabilization adjustment direction or the stabilization maintenance direction, the angle of attack stabilization reference value is read, the stabilization intensity correction angle is selected according to the operating condition change intensity parameter, the stabilization stability correction angle is selected according to the operating condition stability parameter, and the angle of attack stabilization target value is generated based on the angle of attack stabilization reference value, the stabilization intensity correction angle, and the stabilization stability correction angle; the stabilization step size correction amount is selected according to the operating condition change intensity parameter, and the current stabilization step size is generated based on the stabilization base step size and the stabilization step size correction amount, which is used as the current adjustment step size;

[0030] When the current adjustment direction is the drag reduction adjustment direction or the drag reduction holding direction, read the angle of attack drag reduction reference value, select the drag reduction intensity correction angle according to the working condition change intensity parameter, select the drag reduction stability correction angle according to the working condition stability parameter, and generate the angle of attack drag reduction target value based on the angle of attack drag reduction reference value, drag reduction intensity correction angle and drag reduction stability correction angle; select the drag reduction step size correction amount according to the working condition change intensity parameter, and generate the current drag reduction step size based on the drag reduction base step size and drag reduction step size correction amount, which is used as the current adjustment step size.

[0031] Furthermore, the methods for generating the current target tail fin angle of attack, constructing the target tail fin angle of attack sequence, and outputting it include:

[0032] When the current adjustment direction is a stabilization adjustment direction or a stabilization maintenance direction, the previous target tail fin angle of attack is added to the current adjustment step size to obtain a stabilization candidate angle of attack. If the stabilization candidate angle of attack is greater than the angle of attack stabilization target value, the current target tail fin angle of attack is limited to the angle of attack stabilization target value. When the current adjustment direction is a drag reduction adjustment direction or a drag reduction maintenance direction, the previous target tail fin angle of attack is subtracted from the current adjustment step size to obtain a drag reduction candidate angle of attack. If the drag reduction candidate angle of attack is less than the angle of attack drag reduction target value, the current target tail fin angle of attack is limited to the angle of attack drag reduction target value.

[0033] Compare the target angle difference between the current target tail fin angle of attack and the previous target tail fin angle of attack, and when the absolute value of the target angle difference is greater than the maximum angle of attack change per unit sampling period, apply a change constraint to the current target tail fin angle of attack; write the constrained current target tail fin angle of attack into the target angle of attack buffer, construct the target tail fin angle of attack sequence and output it.

[0034] Furthermore, the methods for obtaining the angle-of-attack stabilization judgment value and the angle-of-attack drag reduction judgment value include:

[0035] Numerical conversion is performed on the parameters of working condition change direction, working condition change intensity, and working condition stability. When the working condition change direction parameter is a curve entry trend or a steady-state curve over trend, the demand value of the angle of attack stabilization direction is recorded as one, and the demand value of the angle of attack drag reduction direction is recorded as zero.

[0036] When the direction parameter of the working condition change is a straight acceleration trend or a corner exit trend, the demand value of the angle of attack stabilization direction is recorded as zero, and the demand value of the angle of attack drag reduction direction is recorded as one.

[0037] Multiply the strength level value by the strength weight to obtain the strength weighted value, multiply the stability level value by the stability weight to obtain the stability weighted value, add the strength weighted value and the stability weighted value to obtain the switching base value, and multiply them by the angle of attack stabilization direction requirement value and the angle of attack drag reduction direction requirement value respectively to generate the angle of attack stabilization judgment value and the angle of attack drag reduction judgment value.

[0038] Furthermore, methods for outputting tail fin target state switching commands or maintaining the current tail fin state include:

[0039] Construct a switching buffer decision region for switching from angle-of-attack drag reduction state to angle-of-attack stabilization state, and a switching buffer decision region for switching from angle-of-attack stabilization state to angle-of-attack drag reduction state;

[0040] When the current tail fin state record value is angle of attack and drag reduction state, and the angle of attack stabilization judgment value is not less than the angle of attack stabilization entry boundary value and the angle of attack and drag reduction judgment value is not greater than the angle of attack and drag reduction exit boundary value, the duration of entering the angle of attack and stabilization state is accumulated, and when the duration is not less than the shortest holding time, the tail fin target state switching command to switch to the angle of attack and stabilization state is output.

[0041] When the current tail fin state record value is angle of attack stabilization state, and the angle of attack drag reduction judgment value is not less than the angle of attack drag reduction entry boundary value and the angle of attack stabilization judgment value is not greater than the angle of attack stabilization exit boundary value, the duration of entering the angle of attack drag reduction state is accumulated, and when the duration is not less than the shortest holding time, the tail fin target state switching command to switch to the angle of attack drag reduction state is output.

[0042] If the above conditions are not met, maintain the current tail fin configuration.

[0043] Furthermore, the method for generating the set of operating condition trend parameters includes:

[0044] Based on the smoothed values ​​of vehicle speed, brake pedal opening, steering wheel angle, and actual rear wing angle corresponding to the current sampling period, as well as the historical smoothed values ​​corresponding to several sampling periods in the past historical comparison period, calculate the rate of change of vehicle speed, brake pedal opening, absolute value of steering wheel angle, and actual rear wing angle.

[0045] Based on the comparison relationship between each rate of change and the corresponding increase threshold and decrease threshold, the direction of vehicle speed change, the direction of brake pedal opening change, the direction of steering input change, and the direction of tail wing attitude change are determined; each direction of change is compared with adjacent sampling periods within the current time window to obtain the direction consistency count value, direction reversal count value, and stability maintenance count value, and the direction consistency degree, direction fluctuation degree, and stability maintenance degree are generated.

[0046] The parameters for the direction of change of operating conditions, the intensity of change of operating conditions, and the degree of stability of operating conditions are generated by combining the current steering amplitude, and a set of operating condition trend parameters is constructed.

[0047] An intelligent electronically controlled adjustable tail fin adaptive control system, used to implement the aforementioned intelligent electronically controlled adjustable tail fin adaptive control method, includes:

[0048] The operating condition trend recognition module generates a set of operating condition trend parameters based on vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data.

[0049] The switching buffer decision module is used to generate angle of attack stabilization judgment value and angle of attack drag reduction judgment value based on the working condition trend parameter set, construct the tail fin state switching buffer judgment system, and perform out-of-bounds judgment according to the current tail fin state record value. Combining the cumulative duration of entering the corresponding state and the shortest holding time, it outputs the tail fin target state switching command or maintains the current tail fin state unchanged.

[0050] The continuous angle of attack generation module is used to determine the current adjustment direction based on the tail fin target state switching command, the current tail fin state record value, the working condition trend parameter set and the actual tail fin angle data, generate the corresponding target state angle of attack and the current adjustment step size, call the corresponding angle of attack change trajectory to generate the current target tail fin angle of attack in sampling period, and construct and output the target tail fin angle of attack sequence after executing the change amount constraint.

[0051] The closed-loop vibration suppression execution module is used to read the target tail fin angle of attack sequence and the actual tail fin angle data, calculate the angle deviation between the current target tail fin angle of attack and the current actual tail fin angle, generate a tail fin execution drive signal based on the angle deviation, and perform adaptive vibration suppression correction on the tail fin execution drive signal according to the actual tail fin angle change rate, the number of reverse corrections and the tail fin attitude fluctuation amplitude, and output the corrected tail fin execution drive signal to the tail fin actuator.

[0052] Compared with existing technologies, the intelligent electronically controlled adjustable tail fin adaptive control method and system proposed in this invention have the following technical effects and advantages:

[0053] This invention addresses the problems of existing adjustable rear wing control schemes, which are susceptible to fluctuations in vehicle speed, changes in braking input, steering input disturbances, and execution feedback deviations during dynamic operation transitions such as straight-line acceleration, cornering, steady-state cornering, and cornering exit. These issues lead to frequent switching of the rear wing state near critical boundaries, abrupt changes in the rear wing angle of attack and aerodynamic torque, vehicle attitude disturbances, and repetitive actuator actions. An adaptive control link for multi-source operating states is constructed to address these problems. By performing time window processing, anomaly suppression, trend extraction, and consistency analysis on vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data, the system can transform instantaneous sampling judgment into operation condition identification based on continuous evolution characteristics, improving the stability, noise resistance, and forward-looking nature of operation condition determination.

[0054] By introducing entry boundary, exit boundary, and duration constraints into the state switching determination, the tail fin state switching is transformed from single-point triggering to a combination of interval and continuous determination. This effectively reduces the amplification effect of small disturbances near the critical operating condition on the switching result and avoids frequent tail fin vibration between the angle-of-attack stabilization state and the angle-of-attack drag reduction state. At the same time, by converting the state-level adjustment result into a continuously changing target angle of attack and combining it with execution feedback to adaptively suppress vibration correction of the driving quantity, the actual tail fin angle can approach the target position in a constrained and convergent manner, reducing overshoot, yaw, and high-frequency oscillations.

[0055] In summary, this invention achieves stable switching of tail fin state and continuous adjustment of angle of attack, suppresses frequent jumps under critical conditions, executes chattering and attitude disturbances, and improves tail fin control stability and tracking accuracy. Attached Figure Description

[0056] Figure 1 This is a schematic diagram of an intelligent electronically controlled adjustable tail fin adaptive control system according to Embodiment 1 of the present invention;

[0057] Figure 2 This is a flowchart of an intelligent electronically controlled adjustable tail fin adaptive control method according to Embodiment 2 of the present invention;

[0058] Figure 3 This is a flowchart of the method for generating a set of operating condition trend parameters according to Embodiment 1 of the present invention;

[0059] Figure 4 This is a flowchart of the method for generating tail fin drive signals and performing adaptive vibration suppression correction in Embodiment 1 of the present invention. Detailed Implementation

[0060] The technical solutions of the embodiments of the present invention will be described in detail, clearly, and completely below with reference to the accompanying drawings. It should be particularly noted that the specific embodiments described below are only for better illustrating and explaining the technical solutions of the present invention, and are intended to enable those skilled in the art to better understand and implement the present invention, and should not be construed as limiting the scope of protection of the present invention. Without departing from the spirit and substance of the present invention, those skilled in the art can modify, adjust, or make equivalent substitutions based on the content disclosed in the present invention, and these should all be considered within the scope of protection of the present invention.

[0061] Example 1:

[0062] Please see Figure 1 As shown in the figure, this embodiment discloses an intelligent electronically controlled adjustable tail fin adaptive control system, including a working condition trend recognition module, a switching buffer decision module, a continuous angle of attack generation module, and a closed-loop vibration suppression execution module. Each module is connected by wires and / or wirelessly to realize data transmission.

[0063] The operating condition trend recognition module generates a set of operating condition trend parameters based on vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data.

[0064] like Figure 3 As shown, the methods for generating the set of operating condition trend parameters include:

[0065] Time window caching, anomaly correction, and smoothing are performed on vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data to obtain smoothed values ​​for vehicle speed, brake pedal opening, steering wheel angle, and actual rear wing angle.

[0066] Based on the smoothed value corresponding to the current sampling period and the historical smoothed values ​​corresponding to several sampling periods in the past historical comparison period, calculate the vehicle speed change rate, brake pedal opening change rate, steering wheel angle absolute value change rate and rear wing actual angle change rate, and determine the direction of vehicle speed change, brake pedal opening change direction, steering input change direction and rear wing attitude change direction accordingly.

[0067] Perform trend consistency analysis on each direction of change to obtain the degree of directional consistency, the degree of directional fluctuation, and the degree of stability. Then, combine the current turning amplitude to generate parameters of the direction of change of operating conditions, parameters of the intensity of change of operating conditions, and parameters of the degree of stability of operating conditions, and construct a set of operating condition trend parameters.

[0068] Methods for implementing time window caching, exception correction, and smoothing include:

[0069] Separate buffers are established for vehicle speed data, brake pedal opening data, steering wheel angle data, and rear wing actual angle data. The corresponding sampled values ​​are written according to the preset sampling period. When the number of data in the buffer exceeds the window capacity, the earliest written historical sampled value is deleted.

[0070] Read the current window data sequence from each buffer, calculate the corresponding window midpoint, and replace the sampled value whose difference from the window midpoint is greater than the corresponding anomaly threshold with the window midpoint to obtain the correction sequence;

[0071] Smoothing weights are assigned to the sampled values ​​in each correction sequence in chronological order from early to late. The product of each sampled value and its corresponding smoothing weight is accumulated to obtain the smoothed values ​​of vehicle speed, brake pedal opening, steering wheel angle, and actual rear wing angle corresponding to the current sampling period.

[0072] Furthermore, the more specific implementation of the operating condition trend recognition module is as follows:

[0073] The operating condition trend recognition module periodically receives vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data during vehicle operation. Based on these data, it generates a set of operating condition trend parameters. The module first sets a preset sampling period and a preset time window length, and then determines the window capacity based on the number of sampling points corresponding to the preset time window length.

[0074] The operating condition trend recognition module establishes vehicle speed data cache, brake pedal opening data cache, steering wheel angle data cache, and rear wing actual angle data cache to store vehicle speed sampling values, brake pedal opening sampling values, steering wheel angle sampling values, and rear wing actual angle sampling values ​​arranged in chronological order of sampling time, respectively. At each sampling cycle, the operating condition trend recognition module reads the current vehicle speed data, brake pedal opening data, steering wheel angle data, and rear wing actual angle data, and writes them into the corresponding cache. When the number of data in any cache exceeds the window capacity, the earliest written historical sampling value in that cache is deleted, ensuring that the vehicle speed data cache, brake pedal opening data cache, steering wheel angle data cache, and rear wing actual angle data cache always retain the original sampling sequence within the most recent time window.

[0075] To reduce the impact of jitter, instantaneous spikes, and local outliers at individual sampling points on subsequent operating condition identification, the operating condition trend identification module performs smoothing processing on the current window data sequence in the vehicle speed data buffer, brake pedal opening data buffer, steering wheel angle data buffer, and rear wing actual angle data buffer at the end of each sampling cycle.

[0076] The specific processing steps are as follows: First, the vehicle speed window sequence in the vehicle speed data buffer is read. The midpoint of the vehicle speed window is calculated according to the time sequence, and each vehicle speed sample value in the sequence is compared with the midpoint. When the difference between a vehicle speed sample value and the midpoint exceeds a preset abnormal speed threshold, the sample value is replaced with the midpoint, resulting in a corrected speed sequence. The operating condition trend recognition module then assigns vehicle speed smoothing weights to each vehicle speed sample value in the corrected speed sequence in chronological order, with higher smoothing weights for sample values ​​closer to the current sampling time. The total weight of all smoothing weights is set to one. Each vehicle speed sample value in the corrected speed sequence is multiplied by its corresponding smoothing weight, and the products are summed to obtain the smoothed speed value for the current sampling period. Brake pedal opening data, steering wheel angle data, and actual rear wing angle data are processed in the same way as vehicle speed data to obtain brake pedal opening correction sequences, steering wheel angle correction sequences, and actual rear wing angle correction sequences, respectively. Furthermore, the smoothed values ​​of brake pedal opening, steering wheel angle, and actual rear wing angle corresponding to the current sampling period are obtained.

[0077] The operating condition trend recognition module writes the smoothed vehicle speed value obtained in the current sampling period into the vehicle speed smoothing buffer, the smoothed brake pedal opening value obtained in the current sampling period into the brake pedal opening smoothing buffer, the smoothed steering wheel angle value obtained in the current sampling period into the steering wheel angle smoothing buffer, and the smoothed rear wing actual angle value obtained in the current sampling period into the rear wing actual angle smoothing buffer. When the number of data in any smoothing buffer exceeds the corresponding capacity, the earliest written historical smoothed value is deleted, so that the vehicle speed smoothing buffer, brake pedal opening smoothing buffer, steering wheel angle smoothing buffer, and rear wing actual angle smoothing buffer continuously form a smoothed sequence of vehicle speed, brake pedal opening, steering wheel angle, and rear wing actual angle arranged in the order of sampling time.

[0078] After generating smoothed sequences for vehicle speed, brake pedal opening, steering wheel angle, and rear wing angle, the operating condition trend recognition module extracts the rate of change from these smoothed sequences. The module pre-sets a historical comparison period number, which represents the number of sampling periods between the current sampling period and historical sampling periods when calculating the rate of change. At each sampling period, the module reads the smoothed vehicle speed value corresponding to the current sampling period from the vehicle speed smoothing buffer, and the historical smoothed vehicle speed value corresponding to several historical comparison periods. It then subtracts the historical smoothed vehicle speed value from the current smoothed vehicle speed value and divides the difference by the time length corresponding to the historical comparison period number to obtain the vehicle speed rate of change. The operating condition trend recognition module reads the brake pedal opening smooth value corresponding to the current sampling period from the brake pedal opening smooth buffer, as well as the historical brake pedal opening smooth value corresponding to several sampling periods in the past comparison period. The module subtracts the historical brake pedal opening smooth value from the current brake pedal opening smooth value and divides the difference by the time length corresponding to the number of historical comparison periods to obtain the brake pedal opening change rate.

[0079] The operating condition trend recognition module reads the smoothed steering wheel angle value corresponding to the current sampling period from the steering wheel angle smoothing buffer, and the historical smoothed steering wheel angle values ​​corresponding to several sampling periods prior to the current sampling period. It first takes the absolute value of the current smoothed steering wheel angle value and the absolute value of the historical smoothed steering wheel angle values, then subtracts the historical smoothed steering wheel angle values ​​from the current absolute value, and divides the difference by the time length corresponding to the number of historical comparison periods to obtain the rate of change of the absolute value of the steering wheel angle. Similarly, the operating condition trend recognition module reads the smoothed actual tail wing angle value corresponding to the current sampling period from the rear wing actual angle smoothing buffer, and the historical smoothed actual tail wing angle values ​​corresponding to several sampling periods prior to the current sampling period. It subtracts the historical smoothed actual tail wing angle values ​​from the current actual tail wing angle smoothing value, and divides the difference by the time length corresponding to the number of historical comparison periods to obtain the rate of change of the actual tail wing angle. The time length corresponding to the number of historical comparison periods is equal to the product of the number of historical comparison periods and the preset sampling period. The absolute value of the steering wheel angle change rate is used as a representation of the change in steering input. It is used to represent the increase, decrease and maintenance of the steering input strength, without distinguishing between left and right turn directions, so that subsequent working condition judgments are based on the change in steering input amplitude.

[0080] The operating condition trend recognition module determines the direction of change in vehicle speed, brake pedal opening, steering input, and rear wing attitude based on the rate of change of vehicle speed, brake pedal opening, steering wheel angle, and actual rear wing angle. Specifically, the determination rule is as follows: when the rate of change of vehicle speed is greater than a preset speed increase threshold, the direction of change of vehicle speed is recorded as increasing; when the rate of change of vehicle speed is less than a preset speed decrease threshold, the direction of change of vehicle speed is recorded as decreasing; when the rate of change of vehicle speed is between the preset speed increase and decrease thresholds, the direction of change of vehicle speed is recorded as remaining constant. The direction of change of brake pedal opening, steering input, and rear wing attitude uses the same determination logic as the direction of change of vehicle speed, and corresponds to their respective increase and decrease thresholds. To avoid extremely small fluctuations being misjudged as valid changes, the absolute values ​​of the preset speed increase and decrease thresholds are equal. Similarly, the increase and decrease thresholds for brake pedal opening, steering wheel angle, and actual rear wing angle are also set using the method of equal absolute values. After obtaining the above four directions of change in each sampling period, the working condition trend recognition module writes the direction of vehicle speed change, the direction of brake pedal opening change, the direction of steering input change, and the direction of tail wing attitude change into the direction determination buffer in the order of sampling time to form a continuously updated direction determination sequence.

[0081] After forming the direction determination sequence, the operating condition trend identification module performs trend consistency analysis. Within the current time window, the operating condition trend identification module compares the vehicle speed change direction of two adjacent sampling periods one by one to see if they are the same. If they are the same and neither is maintained, the vehicle speed direction consistency count is incremented by one. If the vehicle speed change direction of the previous sampling period is increasing and the vehicle speed change direction of the next sampling period is decreasing, or if the vehicle speed change direction of the previous sampling period is decreasing and the vehicle speed change direction of the next sampling period is increasing, the vehicle speed direction reversal count is incremented by one. If the vehicle speed change direction of the next sampling period is maintained, the vehicle speed stability count is incremented by one. The direction of brake pedal opening change, the direction of steering input change, and the direction of rear wing attitude change are statistically analyzed using the same method as the direction of vehicle speed change. This yields the following counts: brake pedal opening direction consistent count, brake pedal opening direction reversal count, brake pedal opening stability maintenance count, steering input direction consistent count, steering input direction reversal count, steering input stability maintenance count, and rear wing attitude direction consistent count, rear wing attitude direction reversal count, and rear wing attitude stability maintenance count.

[0082] The operating condition trend recognition module adds the vehicle speed direction consistency count, brake pedal opening direction consistency count, steering input direction consistency count, and rear wing attitude direction consistency count to obtain the total direction consistency count. Then, it divides this total by the total number of valid comparisons for the four types of directional changes within the current time window to obtain the degree of direction consistency. Similarly, it adds the vehicle speed direction reversal count, brake pedal opening direction reversal count, steering input direction reversal count, and rear wing attitude direction reversal count to obtain the total direction reversal count. This total is then divided by the total number of valid comparisons for the four types of directional changes within the current time window to obtain the degree of direction fluctuation. Finally, it adds the vehicle speed stability maintenance count, brake pedal opening stability maintenance count, steering input stability maintenance count, and rear wing attitude stability maintenance count to obtain the total stability maintenance count. This total is then divided by the total number of direction determinations for the four types of directional changes within the current time window to obtain the degree of stability maintenance.

[0083] It should be noted that the degree of directional consistency is used to characterize whether various input changes within the current time window continue to move in the same direction, the degree of directional fluctuation is used to characterize whether various input changes within the current time window frequently reverse direction, and the degree of stability is used to characterize whether various input changes within the current time window remain in a stable state for a long period of time.

[0084] The driving condition trend recognition module generates a driving condition trend parameter set based on the direction of vehicle speed change, brake pedal opening change, steering input change, rear wing attitude change, current steering amplitude, directional consistency, directional fluctuation, and stability. The driving condition trend parameter set includes driving condition change direction parameters, driving condition change intensity parameters, and driving condition stability parameters. The current steering amplitude is an amplitude parameter obtained by taking the absolute value of the smoothed steering wheel angle corresponding to the current sampling period, used to characterize the magnitude of the current steering input without distinguishing between left and right turns. The driving condition trend recognition module pre-sets a preset straight-line threshold and a preset cornering threshold, with the preset straight-line threshold being less than the preset cornering threshold. The preset straight-line threshold characterizes the upper limit of steering amplitude under near-straight-line driving conditions, and the preset cornering threshold characterizes the lower limit of steering amplitude under significant cornering conditions.

[0085] The operating condition change direction parameters are generated according to a preset judgment sequence. First, it is determined whether the cornering trend condition is met; when the vehicle speed change direction is decreasing, the brake pedal opening change direction is increasing, the steering input change direction is increasing, and the current steering amplitude is greater than the preset straight-line threshold, the operating condition change direction parameter is recorded as the cornering trend. If the cornering trend condition is not met, it is further determined whether the cornering trend condition is met; when the vehicle speed change direction is increasing, the brake pedal opening change direction is decreasing, the steering input change direction is decreasing, and the current steering amplitude is greater than the preset straight-line threshold, the operating condition change direction parameter is recorded as the cornering trend. If the cornering trend condition is not met, it is further determined whether the straight-line acceleration trend condition is met; when the vehicle speed change direction is increasing, the brake pedal opening change direction is maintaining, and the current steering amplitude is not greater than the preset straight-line threshold, the operating condition change direction parameter is recorded as the straight-line acceleration trend. If the straight-line acceleration trend condition is not met, the steady-state cornering trend condition is then determined. When the current steering amplitude is greater than the preset cornering threshold, the steering input change direction is maintained, the brake pedal opening change direction is maintained, the vehicle speed change direction is maintained, and the stable state corresponding to the operating condition stability parameter is not lower than the transitional stability, the operating condition change direction parameter is recorded as the steady-state cornering trend. If none of the above conditions are met, the operating condition change direction parameter is recorded as the transitional change trend. By determining each item in a fixed order—entry-cornering trend, exit-cornering trend, straight-line acceleration trend, steady-state cornering trend, and transitional change trend—the operating condition change direction parameter can correspond to a unique output result in each sampling period, avoiding ambiguity when multiple conditions are met simultaneously or all conditions are not met.

[0086] The operating condition change intensity parameters are generated jointly based on the absolute values ​​of the vehicle speed change rate, brake pedal opening change rate, steering wheel angle change rate, and rear wing actual angle change rate. The operating condition trend recognition module pre-sets benchmark values ​​for vehicle speed intensity, brake pedal opening intensity, steering input intensity, and rear wing attitude intensity. It then compares the absolute values ​​of the vehicle speed change rate, brake pedal opening change rate, steering wheel angle change rate, and rear wing attitude intensity with these benchmark values, respectively, to obtain the vehicle speed intensity component, brake pedal opening intensity component, steering input intensity component, and rear wing attitude intensity component. The operating condition trend recognition module then performs a weighted average of these components according to preset component weights to obtain a comprehensive change intensity value, where the sum of the preset component weights is set to one.

[0087] The working condition trend recognition module compares the comprehensive change intensity value with preset low intensity thresholds and preset high intensity thresholds. When the comprehensive change intensity value is not greater than the preset low intensity threshold, the working condition change intensity parameter is recorded as low intensity. When the comprehensive change intensity value is greater than the preset low intensity threshold but not greater than the preset high intensity threshold, the working condition change intensity parameter is recorded as medium intensity. When the comprehensive change intensity value is greater than the preset high intensity threshold, the working condition change intensity parameter is recorded as high intensity.

[0088] The stability parameters are generated based on the degree of directional consistency, the degree of directional fluctuation, and the degree of stability maintenance. The operating condition trend identification module pre-sets weights for consistency, fluctuation, and stability maintenance, all of which are positive, and the sum of their weights is set to one. The operating condition trend identification module first multiplies the directional consistency by the preset consistency weight to obtain a consistency-weighted value; then multiplies the directional fluctuation by the preset fluctuation weight to obtain a fluctuation-weighted value; then multiplies the stability maintenance by the preset stability maintenance weight to obtain a stability-weighted value; the consistency-weighted value and the stability-weighted value are added together to obtain a positive stability value; finally, the fluctuation-weighted value is subtracted from the positive stability value to obtain the comprehensive stability index. The operating condition trend identification module compares the comprehensive stability index with the preset upper stability threshold and the preset lower stability threshold. When the comprehensive stability index is not less than the preset upper stability threshold, the operating condition stability parameter is recorded as high stability. When the comprehensive stability index is less than the preset upper stability threshold but not less than the preset lower stability threshold, the operating condition stability parameter is recorded as transitional stability. When the comprehensive stability index is less than the preset lower stability threshold, the operating condition stability parameter is recorded as low stability.

[0089] In one embodiment, the present invention can be applied to electric vehicles and further includes a networked data acquisition unit. The operating condition trend recognition module is deployed in the vehicle's local onboard control unit. The onboard control unit repeatedly executes the following processes according to a preset sampling cycle: writing raw data, updating raw data cache, smoothing processing, writing smoothed values, extracting the rate of change, determining direction, analyzing trend consistency, generating the operating condition trend parameter set, and outputting the effective trend parameter set, thereby forming a continuously updated operating condition trend recognition result. The onboard control unit is implemented using a microcontroller or other embedded processor. Because the operating condition trend recognition module performs smoothing processing and trend recognition based on continuously updated vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data within the current time window, it can more accurately reflect the continuous change process of the vehicle's operating condition compared to directly using a single sample value to determine the current operating condition. It also provides a stable, continuous, and verifiable input basis for the subsequent switching buffer decision module.

[0090] The vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data can be collected locally by onboard sensors, or synchronously acquired through onboard networks, onboard gateways, edge nodes, or remote platforms. For data acquired synchronously over the network, the operating condition trend recognition module first performs unified time-series alignment of the data source based on timestamps, and then writes the latest aligned data into the corresponding cache. Therefore, the operating condition trend recognition module can perform operating condition trend recognition based on local real-time sampled data, and can also call network-updated data to participate in the generation of the operating condition trend parameter set in multi-node collaboration or remote data synchronization scenarios, thereby improving the completeness and continuity of data acquisition in complex operating environments.

[0091] The vehicle speed window sequence refers to the set of continuous vehicle speed samples read from the vehicle speed data buffer by the operating condition trend recognition module at the end of the current sampling period. These samples are located within the current time window and arranged from earliest to latest according to their sampling time. If the preset sampling period is set to 0.05 seconds and the preset time window length is set to 0.35 seconds, the window capacity is seven sampling points. In this case, the vehicle speed window sequence consists of seven vehicle speed samples corresponding to the most recent seven sampling periods. The first vehicle speed sample is the earliest collected vehicle speed sample within the current time window, and the seventh vehicle speed sample is the vehicle speed sample corresponding to the current sampling period. The brake pedal opening window sequence, steering wheel angle window sequence, and rear wing actual angle window sequence are formed in the same way as the vehicle speed window sequence. They represent the sets of continuous brake pedal opening samples, continuous steering wheel angle samples, and continuous rear wing actual angle samples arranged from earliest to latest according to their sampling time within the current time window, respectively. The aforementioned window value refers to the middle sample value after reordering the sample values ​​in the current window sequence according to their numerical values; when the window capacity is seven sample points, the window value is the fourth sample value after sorting.

[0092] The preset vehicle speed anomaly threshold is used to determine whether a vehicle speed sample value in a vehicle speed window sequence deviates from the normal range of variation within the current time window. The preset vehicle speed anomaly threshold is set by first determining the upper limit of the vehicle speed measurement error based on the vehicle speed sensor calibration results, and then determining the maximum normal deviation of the vehicle speed sample value relative to the middle value of the vehicle speed window under the current sampling period and current time window length based on actual vehicle test or bench test results. The upper limit of the vehicle speed measurement error and the maximum normal deviation are added together to obtain the preset vehicle speed anomaly threshold. As a data example, if the upper limit of the vehicle speed sensor's speed measurement error is 1 km / h, and under the conditions of a sampling period of 0.05 seconds and a time window length of 0.35 seconds, the maximum normal deviation of the vehicle speed sample value relative to the middle value of the vehicle speed window is found to be 6 km / h, then the preset vehicle speed anomaly threshold is set to 7 km / h. If the current vehicle speed window sequence is 98, 100, 101, 132, 102, 103, and 104, then the seven vehicle speed sample values ​​are sorted according to their numerical values ​​to obtain 98, 100, 101, 102, 103, 104, and 132. The value of the fourth vehicle speed window is 102. The working condition trend recognition module calculates the difference between each vehicle speed sample value and the value of the vehicle speed window. The difference between 132 and 102 is 30, which is greater than the preset abnormal vehicle speed threshold of 7 kilometers per hour. Therefore, 132 in the vehicle speed window sequence is replaced with 102, resulting in the vehicle speed correction sequence 98, 100, 101, 102, 102, 103, and 104.

[0093] The preset vehicle speed smoothing weights are used to time-weight each vehicle speed sample value in the vehicle speed correction sequence, so that the vehicle speed sample value closer to the current sampling period has a greater impact on the current smoothed vehicle speed value. The preset vehicle speed smoothing weights are set by first determining the weight distribution method based on the jitter level and response speed requirements of the vehicle speed signal, then assigning increasing weights to each vehicle speed sample value in the vehicle speed correction sequence in ascending order, and finally ensuring that the sum of all vehicle speed smoothing weights is one. As a data example, with a window size of seven sampling points, the vehicle speed smoothing weights corresponding to the seven vehicle speed sample values ​​from earliest to latest are set to 0.08, 0.10, 0.12, 0.15, 0.17, 0.18, and 0.20 respectively. The operating condition trend recognition module multiplies 98, 100, 101, 102, 102, 103, and 104 in the vehicle speed correction sequence with their corresponding vehicle speed smoothing weights, and then sums the results to obtain the smoothed vehicle speed value corresponding to the current sampling period. When calculating using the data example above, the current smoothed vehicle speed value is 102.02. Using the above incremental weighting method allows for a higher proportion of the most recent vehicle speed information in the smoothed speed value, thus suppressing the influence of outliers while preserving the trend of vehicle speed changes.

[0094] The abnormal thresholds and corresponding smoothing weights for brake pedal opening data, steering wheel angle data, and actual rear spoiler angle data are set using the same logic as for vehicle speed data. Specifically, the abnormal threshold for brake pedal opening is determined jointly based on the upper limit of the measurement error of the brake pedal position sensor and the maximum normal fluctuation of the brake input within the current time window. As a data example, if the upper limit of the measurement error of the brake pedal position sensor is two percentage points, and the maximum normal deviation of the brake pedal opening sample value from the middle value of the brake pedal opening window is ten percentage points, then the preset abnormal threshold for brake pedal opening is set to twelve percentage points. With a window capacity of seven sampling points, the smoothing weights for the seven brake pedal opening sample values ​​from morning to evening are set sequentially to 0.06, 0.08, 0.11, 0.14, 0.17, 0.20, and 0.24. The abnormal threshold for steering wheel angle is determined jointly based on the upper limit of the measurement error of the steering wheel angle sensor and the maximum normal fluctuation of the steering input within the current time window. As a data example, if the upper limit of the measurement error of the steering wheel angle sensor is two degrees, and the maximum normal deviation of the steering wheel angle sample value from the middle value of the steering wheel angle window is found to be thirteen degrees through experimentation, then the preset steering wheel angle anomaly threshold is set to fifteen degrees. With a window capacity of seven sampling points, the smoothing weights of the steering wheel angles corresponding to the seven steering wheel angle sample values ​​from morning to evening are set to 0.07, 0.09, 0.11, 0.14, 0.17, 0.19, and 0.23 respectively. The actual angle anomaly threshold of the tail wing is determined jointly based on the upper limit of the measurement error of the tail wing angle sensor and the maximum normal attitude fluctuation of the tail wing actuator within the current time window. As a data example, if the upper limit of the measurement error of the tail wing angle sensor is 0.5 degrees, and the maximum normal deviation of the actual tail wing angle sample value from the middle value of the actual tail wing angle window is found to be 2.5 degrees, then the preset abnormal threshold for the actual tail wing angle is set to 3 degrees. With a window capacity of seven sampling points, the smoothing weights of the actual tail wing angles corresponding to the seven actual tail wing angle sample values ​​from morning to evening are set to 0.10, 0.11, 0.12, 0.14, 0.16, 0.18, and 0.19 respectively. The operating condition trend identification module obtains the smoothed values ​​of the brake pedal opening, steering wheel angle, and actual tail wing angle corresponding to the current sampling period according to the aforementioned abnormal value replacement and time-weighted processing methods.

[0095] The historical comparison period is set to two sampling periods, corresponding to a time length of 0.1 seconds. To determine the direction of change in vehicle speed, brake pedal opening, absolute steering wheel angle, and actual rear wing angle, the operating condition trend recognition module presets thresholds for increasing and decreasing vehicle speed, increasing and decreasing brake pedal opening, increasing and decreasing absolute steering wheel angle, increasing and decreasing actual rear wing angle, and decreasing actual rear wing angle, respectively. These thresholds are determined based on the noise fluctuation range of the smoothed sequence under stable operating conditions and the sensitivity of operating condition change recognition. As a data example, the vehicle speed increase threshold is set to 8 km / h, and the vehicle speed decrease threshold is set to -8 km / h; the brake pedal opening increase threshold is set to 20% per second, and the brake pedal opening decrease threshold is set to -20% per second; the steering wheel angle increase threshold is set to 40 degrees per second, and the steering wheel angle decrease threshold is set to -40 degrees per second; the actual rear wing angle increase threshold is set to 6 degrees per second, and the actual rear wing angle decrease threshold is set to -6 degrees per second. Using the above setting method, when a certain rate of change is between the corresponding increase threshold and decrease threshold, the direction of change corresponding to the rate of change is recorded as maintained, thereby avoiding misjudgment caused by minor noise.

[0096] To generate parameters for the intensity of changes in operating conditions, the operating condition trend recognition module presets benchmark values ​​for vehicle speed, brake pedal opening, steering input, and rear wing attitude, and also presets weights for these components. The benchmark values ​​are determined based on the normal variation range of different input quantities under typical road conditions, used to convert different physical quantities to a comparable intensity scale. The component weights are determined based on the sensitivity of the rear wing control to each input quantity, used to reflect the contribution of different input quantities to the intensity of changes in operating conditions. As a data example, the benchmark value for vehicle speed is set to 15 km / h, the benchmark value for brake pedal opening is set to 30%, the benchmark value for steering input is set to 60 degrees / second, and the benchmark value for rear wing attitude is set to 10 degrees / second; the weights for the four components are set to 0.30, 0.25, 0.25, and 0.20, with the sum of the weights for all four components being 1. After comparing the absolute values ​​of each rate of change with the corresponding strength benchmark values, the vehicle speed strength component, brake pedal opening strength component, steering input strength component, and rear wing attitude strength component are obtained respectively. These components are then weighted and averaged according to their respective weights to obtain the comprehensive change strength value. As a data example, a preset low strength threshold is set to 0.35, and a preset high strength threshold is set to 0.65. When the comprehensive change strength value is not greater than 0.35, the operating condition change strength parameter is recorded as low strength; when the comprehensive change strength value is greater than 0.35 but not greater than 0.65, the operating condition change strength parameter is recorded as medium strength; and when the comprehensive change strength value is greater than 0.65, the operating condition change strength parameter is recorded as high strength.

[0097] To generate the operating condition stability parameters, the operating condition trend identification module presets weights for consistency, volatility, and stability, and also presets upper and lower stability thresholds. The consistency weight represents the positive impact of directional consistency on the overall stability index, the volatility weight represents the negative impact of directional volatility on the overall stability index, and the stability weight represents the positive impact of stability maintenance on the overall stability index. As a data example, the consistency weight is set to 0.45, the volatility weight to 0.35, and the stability weight to 0.20, with the sum of the three weights being 1; the upper stability threshold is set to 0.65, and the lower stability threshold is set to 0.35. The operating condition trend identification module multiplies the directional consistency by its weight, the directional volatility by its weight, and the stability maintenance by its weight. Then, it subtracts the directional volatility weight from the sum of the weighted results of the first two items (weighted results of directional consistency and weighted results of stability maintenance) to obtain the overall stability index. If the overall stability index is not less than 0.65, the operating condition stability parameter is recorded as high stability; if the overall stability index is less than 0.65 but not less than 0.35, the operating condition stability parameter is recorded as transitional stability; if the overall stability index is less than 0.35, the operating condition stability parameter is recorded as low stability.

[0098] The switching buffer decision module is used to generate angle-of-attack stabilization judgment value and angle-of-attack drag reduction judgment value based on the operating condition trend parameter set, construct the tail fin state switching buffer judgment system, and perform out-of-bounds judgment according to the current tail fin state record value. Combining the cumulative duration of entering the corresponding state and the shortest holding time, it outputs the tail fin target state switching command or maintains the current tail fin state unchanged.

[0099] Furthermore, the more specific implementation of the switching buffer decision module is as follows:

[0100] The switching buffer decision module receives the operating condition trend parameter set output by the operating condition trend recognition module and determines whether the current operating condition meets the tail wing state switching requirements based on the operating condition trend parameter set. The switching buffer decision module pre-establishes the current tail wing state record value, the last state switching time, the cumulative duration of entering angle of attack stabilization, and the cumulative duration of entering angle of attack drag reduction. The current tail wing state record value is used to indicate whether the current tail wing is in angle of attack stabilization or angle of attack drag reduction state; the last state switching time is used to record the time when the most recent tail wing state switching occurred; the cumulative duration of entering angle of attack stabilization is used to record the duration for which the current operating condition continuously meets the conditions for switching to angle of attack stabilization; the cumulative duration of entering angle of attack drag reduction is used to record the duration for which the current operating condition continuously meets the conditions for switching to angle of attack drag reduction. Among them, angle of attack stabilization state refers to the tail wing being adjusted to the target angle of attack state to improve vehicle driving stability, and angle of attack drag reduction state refers to the tail wing being adjusted to the target angle of attack state to reduce vehicle air resistance.

[0101] The switching buffer decision module also pre-sets the angle-of-attack stabilization entry boundary value, angle-of-attack stabilization exit boundary value, angle-of-attack drag reduction entry boundary value, angle-of-attack drag reduction exit boundary value, intensity weight, stability weight, and minimum hold time. Specifically, the angle-of-attack stabilization entry boundary value is greater than the angle-of-attack stabilization exit boundary value, and the angle-of-attack drag reduction entry boundary value is greater than the angle-of-attack drag reduction exit boundary value. The angle-of-attack stabilization entry boundary value and the angle-of-attack drag reduction exit boundary value are used together to limit the buffer determination range for switching from the angle-of-attack drag reduction state to the angle-of-attack stabilization state.

[0102] The switching buffer decision module first performs numerical conversion on the parameters of the operating condition change direction, the intensity of the operating condition change, and the stability of the operating condition. Specifically, when the operating condition change direction parameter indicates a cornering trend or a steady-state cornering trend, the demand value for the angle of attack stabilization direction is recorded as one, and the demand value for the angle of attack drag reduction direction is recorded as zero. When the operating condition change direction parameter indicates a straight-line acceleration trend or a cornering exit trend, the demand value for the angle of attack stabilization direction is recorded as zero, and the demand value for the angle of attack drag reduction direction is recorded as one. When the operating condition change direction parameter indicates a transitional change trend, both the demand values ​​for the angle of attack stabilization direction and the angle of attack drag reduction direction are recorded as zero. When the operating condition change intensity parameter is low intensity, the intensity level value is recorded as one; when the operating condition change intensity parameter is medium intensity, the intensity level value is recorded as two; and when the operating condition change intensity parameter is high intensity, the intensity level value is recorded as three. When the operating condition stability parameter is low stability, the stability level value is recorded as zero; when the operating condition stability parameter is transient stability, the stability level value is recorded as one; when the operating condition stability parameter is high stability, the stability level value is recorded as two.

[0103] After the above transformation is completed, the switching buffer decision module generates angle-of-attack stabilization judgment values ​​and angle-of-attack drag reduction judgment values ​​based on the angle-of-attack stabilization direction requirement value, angle-of-attack drag reduction direction requirement value, strength level value, stability level value, strength weight, and stability weight. The specific processing logic is as follows: multiply the strength level value by the strength weight to obtain the strength weighted value; multiply the stability level value by the stability weight to obtain the stability weighted value; add the strength weighted value and the stability weighted value to obtain the switching base value; then multiply the switching base value by the angle-of-attack stabilization direction requirement value and the angle-of-attack drag reduction direction requirement value respectively to obtain the angle-of-attack stabilization judgment value and the angle-of-attack drag reduction judgment value.

[0104] After adopting the above processing method, when the angle of attack stabilization direction requirement value is zero, it is determined that the current operating condition does not have an angle of attack stabilization direction requirement, and the angle of attack stabilization determination value is zero; when the angle of attack drag reduction direction requirement value is zero, it is determined that the current operating condition does not have an angle of attack drag reduction direction requirement, and the angle of attack drag reduction determination value is zero, thereby avoiding the direct triggering of erroneous switching by the intensity of operating condition changes and the degree of operating condition stability that are inconsistent with the current operating condition direction.

[0105] It should be noted that whether the current operating condition requires angle-of-attack stabilization or angle-of-attack drag reduction is not determined subjectively by a single sensor data point at the current moment, but is obtained by converting the operating condition change direction parameters output by the operating condition trend recognition module. When the direction parameter of the operating condition change is a cornering trend or a steady-state cornering trend, it indicates that the current operating condition corresponds to the rear wing stabilization adjustment direction. In this case, the demand value for the angle of attack stabilization direction is recorded as one, and the demand value for the angle of attack drag reduction direction is recorded as zero. Based on this, it is determined that the current operating condition has a demand for the angle of attack stabilization direction but not for the angle of attack drag reduction direction. When the direction parameter of the operating condition change is a straight-line acceleration trend or a cornering exit trend, it indicates that the current operating condition corresponds to the rear wing drag reduction adjustment direction. In this case, the demand value for the angle of attack stabilization direction is recorded as zero, and the demand value for the angle of attack drag reduction direction is recorded as one. Based on this, it is determined that the current operating condition does not have a demand for the angle of attack stabilization direction but has a demand for the angle of attack drag reduction direction. When the direction parameter of the operating condition change is a transitional change trend, it indicates that the current operating condition has not yet formed a clear rear wing adjustment direction. In this case, both the demand values ​​for the angle of attack stabilization direction and the angle of attack drag reduction direction are recorded as zero. Based on this, it is determined that the current operating condition has neither a demand for the angle of attack stabilization direction nor for the angle of attack drag reduction direction. Therefore, the switching buffer decision module's judgment on the demand for angle-of-attack stabilization and drag reduction directions is based on the direction demand value corresponding to the operating condition change direction parameter.

[0106] After obtaining the angle-of-attack stabilization and drag reduction determination values, the switching buffer decision module constructs a tail fin state switching buffer determination zone. When switching from the drag reduction state to the angle-of-attack stabilization state, the switching buffer decision module simultaneously considers both the angle-of-attack stabilization and drag reduction determination values. If the angle-of-attack stabilization determination value is not less than the angle-of-attack stabilization entry boundary value and the angle-of-attack drag reduction determination value is not greater than the angle-of-attack drag reduction exit boundary value, it is determined that the current operating condition has crossed the switching buffer determination zone from the drag reduction state to the angle-of-attack stabilization state. If the angle-of-attack stabilization determination value is less than the angle-of-attack stabilization entry boundary value, or the angle-of-attack drag reduction determination value is greater than the angle-of-attack drag reduction exit boundary value, it is determined that the current operating condition is still within the switching buffer determination zone from the drag reduction state to the angle-of-attack stabilization state.

[0107] When switching from angle-of-attack stabilization to angle-of-attack drag reduction, the switching buffer decision module considers both the angle-of-attack drag reduction judgment value and the angle-of-attack stabilization judgment value. If the angle-of-attack drag reduction judgment value is not less than the angle-of-attack drag reduction entry boundary value, and the angle-of-attack stabilization judgment value is not greater than the angle-of-attack stabilization exit boundary value, the current operating condition is determined to have crossed the switching buffer judgment zone from angle-of-attack stabilization to angle-of-attack drag reduction. If the angle-of-attack drag reduction judgment value is less than the angle-of-attack drag reduction entry boundary value, or the angle-of-attack stabilization judgment value is greater than the angle-of-attack stabilization exit boundary value, the current operating condition is determined to still be within the switching buffer judgment zone from angle-of-attack stabilization to angle-of-attack drag reduction. By simultaneously setting entry and exit boundary values, the tail fin state switching judgment no longer relies on a single threshold, thus forming a buffered judgment interval near the critical operating condition, reducing the risk of back-and-forth tail fin state switching caused by slight fluctuations in operating conditions.

[0108] The switching buffer decision module then constructs a tail fin state switching buffer determination system. This system includes a switching buffer determination region for switching from angle-of-attack drag reduction to angle-of-attack stabilization, and a switching buffer determination region for switching from angle-of-attack stabilization to angle-of-attack drag reduction. The switching buffer determination region for switching from angle-of-attack drag reduction to angle-of-attack stabilization is jointly defined by the angle-of-attack stabilization entry boundary value and the angle-of-attack drag reduction exit boundary value; similarly, the switching buffer determination region for switching from angle-of-attack stabilization to angle-of-attack drag reduction is jointly defined by the angle-of-attack drag reduction entry boundary value and the angle-of-attack stabilization exit boundary value.

[0109] The switching buffer decision module selects the corresponding switching buffer judgment zone based on the current tail fin state record value, and outputs the boundary crossing judgment result for the corresponding direction based on the angle-of-attack stabilization judgment value and the angle-of-attack drag reduction judgment value. The boundary crossing judgment result includes two states: crossing the corresponding switching buffer judgment zone and remaining within the corresponding switching buffer judgment zone. The former indicates that the current operating condition has formed a clear and stable state switching trend, while the latter indicates that the current operating condition is still in the boundary transition stage or a short-term fluctuation stage, and has not yet formed a stable trend sufficient to trigger a tail fin state switching.

[0110] When the current tail fin status record value is in the angle-of-attack drag reduction state, the switching buffer decision module selects the switching buffer judgment area for switching from the angle-of-attack drag reduction state to the angle-of-attack stabilization state to perform an out-of-bounds judgment. If the angle-of-attack stabilization judgment value is not less than the angle-of-attack stabilization entry boundary value and the angle-of-attack drag reduction judgment value is not greater than the angle-of-attack drag reduction exit boundary value, then it is determined that the current operating condition has crossed the switching buffer judgment area for switching from the angle-of-attack drag reduction state to the angle-of-attack stabilization state; if the angle-of-attack stabilization judgment value is less than the angle-of-attack stabilization entry boundary value, or the angle-of-attack drag reduction judgment value is greater than the angle-of-attack drag reduction exit boundary value, then it is determined that the current operating condition is still within the switching buffer judgment area for switching from the angle-of-attack drag reduction state to the angle-of-attack stabilization state.

[0111] It should be noted that when the current operating condition crosses the transition buffer zone from angle-of-attack drag reduction to angle-of-attack stabilization, it indicates that the angle-of-attack stabilization adjustment requirement for the current operating condition has been stably established, while the angle-of-attack drag reduction adjustment requirement has decreased below the exit boundary. At this point, it is permissible to enter the state transition execution phase from angle-of-attack drag reduction to angle-of-attack stabilization. If the current operating condition is still within the transition buffer zone from angle-of-attack drag reduction to angle-of-attack stabilization, it indicates that although the current operating condition has shown a tendency to enter a corner or a steady-state cornering tendency, the corresponding directional requirements have not yet simultaneously met the entry and exit boundary conditions. In this case, it is not permissible to immediately switch the tail wing state.

[0112] When the current tail fin state record value is in the angle-of-attack stabilization state, the switching buffer decision module selects the switching buffer judgment area for switching from the angle-of-attack stabilization state to the angle-of-attack drag reduction state to perform an out-of-bounds judgment. If the angle-of-attack drag reduction judgment value is not less than the angle-of-attack drag reduction entry boundary value and the angle-of-attack stabilization judgment value is not greater than the angle-of-attack stabilization exit boundary value, then it is determined that the current operating condition has crossed the switching buffer judgment area for switching from the angle-of-attack stabilization state to the angle-of-attack drag reduction state; if the angle-of-attack drag reduction judgment value is less than the angle-of-attack drag reduction entry boundary value, or the angle-of-attack stabilization judgment value is greater than the angle-of-attack stabilization exit boundary value, then it is determined that the current operating condition is still within the switching buffer judgment area for switching from the angle-of-attack stabilization state to the angle-of-attack drag reduction state.

[0113] It should be noted that when the current operating condition crosses the transition buffer zone from angle-of-attack stabilization to angle-of-attack drag reduction, it indicates that the corresponding angle-of-attack drag reduction adjustment demand has been stably established, while the angle-of-attack stabilization adjustment demand has decreased below the exit boundary. At this point, it is permissible to enter the state transition execution phase from angle-of-attack stabilization to angle-of-attack drag reduction. If the current operating condition is still within the transition buffer zone from angle-of-attack stabilization to angle-of-attack drag reduction, it indicates that although the current operating condition shows a trend of straight-line acceleration or corner exit, the corresponding directional demand has not yet simultaneously met the entry and exit boundary conditions. In this case, it is not permissible to immediately switch the tail wing state.

[0114] It should be noted that the core technical problem addressed by this invention is that existing adjustable rear wing control schemes typically employ a single threshold or a two-state switching method near critical operating conditions. When vehicle speed, braking input, steering input, or rear wing attitude feedback fluctuates slightly around the threshold, the rear wing easily switches frequently between the two adjustment states, leading to sudden changes in the rear wing angle of attack, aerodynamic torque, vehicle attitude disturbances, and repetitive actuator actions. To solve the above problems, this invention does not use a single judgment value reaching a certain threshold as a sufficient condition for immediately switching the rear wing state. Instead, it constructs a switching buffer judgment area by using angle of attack stabilization entry boundary value, angle of attack stabilization exit boundary value, angle of attack drag reduction entry boundary value, and angle of attack drag reduction exit boundary value together, changing the rear wing state switching from single-point triggering to interval judgment. Only when the current operating condition crosses the corresponding switching buffer judgment zone does it indicate that the original adjustment direction has been fully withdrawn and the target adjustment direction has been stably established. Only then is it allowed to enter the subsequent duration judgment and state switching process. When the current operating condition is still within the switching buffer judgment zone, it indicates that the current operating condition still has boundary transition, uncertainty or instantaneous fluctuation. The current tail fin state should be maintained to avoid misjudging short-term disturbances as effective switching trends.

[0115] Therefore, the setting of the switching buffer judgment zone essentially adds a transition buffer judgment mechanism between the operating condition trend parameter set and the tail wing state switching command, used to distinguish between stable switching trends and critical fluctuation trends. By clearly distinguishing between the two types of states—those that have crossed the switching buffer judgment zone and those that are still within it—this invention can more accurately identify whether the tail wing state should switch under different road conditions such as entering and exiting corners, straight-line acceleration, and steady-state cornering. This suppresses frequent jumps near critical operating conditions, ensures the continuity, stability, and execution reliability of tail wing angle of attack adjustment, and provides a stable switching basis for subsequent continuous angle of attack generation and closed-loop vibration suppression execution.

[0116] The handover buffer decision module further calculates the current state holding duration in each sampling period. The current state holding duration is equal to the time difference between the current moment and the last state handover moment. The handover buffer decision module determines whether the reverse handover suppression condition is triggered based on the current state holding duration. If the current state holding duration is less than the minimum holding duration, the reverse handover suppression condition is triggered; if the current state holding duration is not less than the minimum holding duration, the reverse handover suppression condition is not triggered.

[0117] It should be noted that since the current tail fin state only switches between angle-of-attack stabilization and angle-of-attack drag reduction states, any new state transition is a reverse transition relative to the current tail fin state. By setting a minimum hold duration, it can be ensured that after completing a state transition, the tail fin maintains its current state for a period of time before allowing the next state transition in the opposite direction.

[0118] After completing the boundary violation determination and reverse switching suppression condition determination, the switching buffer decision module performs state switching processing based on the boundary violation determination result. When the current tail fin state record value is the angle-of-attack drag reduction state, the switching buffer decision module reads the boundary violation determination result for switching from the angle-of-attack drag reduction state to the angle-of-attack stabilization state. If the boundary violation determination result is that the switch buffer determination area in the corresponding direction has been crossed, and the reverse switching suppression condition has not been triggered, then the cumulative duration of angle-of-attack stabilization will be increased by a preset sampling period, and the cumulative duration of angle-of-attack drag reduction will be reset to zero; if the boundary violation determination result is that the switch buffer determination area in the corresponding direction is still within the switch buffer determination area, or the reverse switching suppression condition has been triggered, then the cumulative duration of angle-of-attack stabilization will be reset to zero, and the current tail fin state record value will remain in the angle-of-attack drag reduction state. When the cumulative duration of angle-of-attack stabilization is not less than the minimum holding time, the switching buffer decision module outputs a tail fin target state switching command to switch to angle-of-attack stabilization state, updates the current tail fin state record value to angle-of-attack stabilization state, updates the last state switching time to the current time, and resets both the cumulative duration of angle-of-attack stabilization and drag reduction to zero. Therefore, the tail fin only switches from drag reduction state to angle-of-attack stabilization state when the boundary judgment results in the corresponding direction are consecutively true and the minimum holding time is reached.

[0119] When the current tail fin status record value is in the angle-of-attack stabilization state, the switching buffer decision module reads the boundary judgment result of the switch from the angle-of-attack stabilization state to the angle-of-attack drag reduction state. If the boundary judgment result is that the switch buffer judgment area in the corresponding direction has been crossed, and the reverse switching suppression condition has not been triggered, then the cumulative duration of entering the angle-of-attack drag reduction state will be increased by a preset sampling period, and the cumulative duration of entering the angle-of-attack stabilization state will be cleared to zero. If the boundary judgment result is that the switch buffer judgment area in the corresponding direction is still within the switch buffer judgment area, or the reverse switching suppression condition has been triggered, then the cumulative duration of entering the angle-of-attack drag reduction state will be cleared to zero, and the current tail fin status record value will remain in the angle-of-attack stabilization state. When the cumulative duration of entering the angle-of-attack drag reduction state is not less than the minimum holding time, the switching buffer decision module outputs the tail fin target state switching command to switch to the angle-of-attack drag reduction state, updates the current tail fin status record value to the angle-of-attack drag reduction state, updates the last state switching time to the current time, and clears both the cumulative duration of entering the angle-of-attack stabilization state and the cumulative duration of entering the angle-of-attack drag reduction state. Therefore, the tail fin switches from angle-of-attack stabilization to angle-of-attack drag reduction only when the cross-boundary judgment results in the corresponding direction are consecutively valid and the shortest holding time is reached.

[0120] It should be noted that crossing the switching buffer decision area in the corresponding direction and remaining within the switching buffer decision area in the corresponding direction are intermediate decision results output by the switching buffer decision module. These intermediate decision results are not directly equivalent to the tail fin state switching command, but rather serve as the basis for determining whether to proceed with the cumulative duration update and the final state switching execution. By first outputting the intermediate decision results and then combining them with the shortest hold duration to execute the state switching, the establishment of the operating condition trend and the execution of the tail fin state switching can be processed at two different levels, thereby avoiding direct triggering of tail fin state switching due to short-term fluctuations in input near critical operating conditions.

[0121] At the end of each sampling period, the switching buffer decision module outputs either a tail fin target state switching command or a determination result indicating that the current tail fin state remains unchanged, and sends the determination result to the continuous angle of attack generation module. If the output result is a tail fin target state switching command to the angle of attack stabilization state, the continuous angle of attack generation module generates a target tail fin angle of attack sequence based on the adjustment trajectory corresponding to the angle of attack stabilization state; if the output result is a tail fin target state switching command to the angle of attack drag reduction state, the continuous angle of attack generation module generates a target tail fin angle of attack sequence based on the adjustment trajectory corresponding to the angle of attack drag reduction state; if the output result is to maintain the current tail fin state, the continuous angle of attack generation module continues to generate a target tail fin angle of attack sequence using the adjustment direction corresponding to the current tail fin state. Because the switching buffer decision module adds a joint constraint between the operating condition trend parameter set and the tail fin state switching command—including a switching buffer determination system, an out-of-bounds determination result, a minimum holding time, and a reverse switching suppression condition—it can more effectively suppress frequent reciprocating switching of the tail fin near critical operating conditions compared to directly switching the tail fin state based on a single operating condition determination result.

[0122] It should be noted that the preset data in the switching buffer decision module can be jointly determined by vehicle real-world test data, road segment working condition data, and rear wing actuator response data. Specifically, the setting involves first collecting a set of working condition trend parameters under straight-line acceleration, cornering braking, steady-state cornering, and cornering acceleration conditions. The distribution range of the switching baseline values ​​corresponding to the working condition change intensity parameters, working condition stability parameters, angle-of-attack stabilization direction demand values, and angle-of-attack drag reduction direction demand values ​​for each working condition is then statistically analyzed. Next, combining the number of state changes of the rear wing in two adjacent sampling periods, the number of reverse switching times per unit time, and the vehicle attitude fluctuation amplitude, the boundary values ​​and minimum holding time that can distinguish between stable switching trends and critical fluctuation trends are determined. Therefore, the above preset data is not arbitrarily set, but rather determined jointly based on the parameter distribution results under typical road working conditions and the rear wing state switching effect. Furthermore, the road can also be a racetrack.

[0123] Intensity weight and stability weight are used to characterize the contribution of the operating condition change intensity parameter and the operating condition stability parameter to the switching base value. The intensity weight and stability weight are set as follows: first, the importance of the operating condition change intensity parameter is determined based on the vehicle's sensitivity to transient changes in the road; then, the importance of the operating condition stability parameter is determined based on the vehicle's dependence on operating condition stability during transitions between curves and straightaways; finally, both are normalized so that the sum of the intensity weight and the stability weight is one. As a data example, if experiments show that the vehicle is more sensitive to the intensity of operating condition changes during curve entry and exit, and less dependent on the degree of operating condition stability, then the intensity weight can be set to 0.6 and the stability weight to 0.4. When calculating according to the previously defined intensity level and stability level values, when the intensity level is one and the stability level is zero, the switching base value is 0.6; when the intensity level is two and the stability level is one, the switching base value is 1.6; and when the intensity level is three and the stability level is two, the switching base value is 2.6. Therefore, when using the above data example, the range of variation for the switching base value is 0.6 to 2.6.

[0124] The angle-of-attack stabilization entry and exit boundary values ​​are used to define the switching buffer zone between the angle-of-attack drag reduction state and the angle-of-attack stabilization state. The boundary values ​​are set by first statistically analyzing the basic switching value range corresponding to the operating conditions that should actually switch to the angle-of-attack stabilization state during road testing, then statistically analyzing the basic switching value range corresponding to the operating conditions that should not switch due to short-term fluctuations, and finally using the boundary value that can stably distinguish between the two types of operating conditions as the entry boundary value, and using a value slightly lower than the entry boundary value as the exit boundary value, thus forming a buffer zone with hysteresis characteristics. As a data example, under the conditions of an intensity weight of 0.6 and a stability weight of 0.4, the angle-of-attack stabilization entry boundary value can be set to 1.7, and the angle-of-attack stabilization exit boundary value can be set to 1.2; the angle-of-attack drag reduction entry boundary value can be set to 1.6, and the angle-of-attack drag reduction exit boundary value can be set to 1.1. Using the above data examples, when the current tail fin state record value is in the angle-of-attack drag reduction state, and the angle-of-attack stabilization judgment value is not less than 1.7, while the angle-of-attack drag reduction judgment value is not greater than 1.1, it is determined that the current operating condition has crossed the switching buffer judgment zone from the angle-of-attack drag reduction state to the angle-of-attack stabilization state; when the current tail fin state record value is in the angle-of-attack stabilization state, and the angle-of-attack drag reduction judgment value is not less than 1.6, while the angle-of-attack stabilization judgment value is not greater than 1.2, it is determined that the current operating condition has crossed the switching buffer judgment zone from the angle-of-attack stabilization state to the angle-of-attack drag reduction state. Since the entry boundary value is greater than the exit boundary value, the switching judgment in the same direction will not repeatedly jump near a single dividing point.

[0125] The differences between the angle-of-attack stabilization entry boundary value and the angle-of-attack stabilization exit boundary value, as well as the differences between the angle-of-attack drag reduction entry boundary value and the angle-of-attack drag reduction exit boundary value, are used to characterize the boundary intervals of the corresponding directional switching buffer decision zones. The boundary intervals are set by first statistically analyzing the natural fluctuation range of the switching base value over several consecutive sampling periods near the critical operating condition; then, ensuring that the difference between the angle-of-attack stabilization entry boundary value and the angle-of-attack stabilization exit boundary value is greater than the natural fluctuation range, and also ensuring that the difference between the angle-of-attack drag reduction entry boundary value and the angle-of-attack drag reduction exit boundary value is greater than the natural fluctuation range. This avoids frequent back-and-forth changes between crossing the corresponding directional switching buffer decision zone and remaining within the corresponding directional switching buffer decision zone when the current operating condition fluctuates slightly near the boundaries. As a data example, if the experimental statistics show that the natural fluctuation range of the switching base value near the critical operating condition is approximately 0.3, then the angle-of-attack stabilization entry boundary value can be set to 1.7, and the angle-of-attack stabilization exit boundary value to 1.2; the angle-of-attack drag reduction entry boundary value can be set to 1.6, and the angle-of-attack drag reduction exit boundary value to 1.1. With the above settings, when the switching base value fluctuates only between 1.4 and 1.6, the switching buffer decision module will not immediately trigger the tail fin state switch, but will continue to maintain the current tail fin state record value unchanged, thereby suppressing small disturbances near the critical operating condition.

[0126] The minimum hold duration is used to limit the minimum hold time of the tail wing after completing a state transition. The minimum hold duration is set by first recording the execution completion time required for the tail wing actuator to switch from the current state to the target state; then recording the shortest duration for which the condition trend parameter set remains stable under typical operating conditions such as braking at the end of a straight road, steady state in a curve, and acceleration out of a curve; finally, taking a value that is not less than the execution completion time and not greater than the lower limit of the stable operating condition duration as the minimum hold duration. As a data example, if the time required for the tail wing actuator to complete a state transition is 0.25 seconds, and the typical stable switching trend duration in road tests is usually greater than 0.4 seconds, then the minimum hold duration can be set to 0.3 seconds. If the previously preset sampling period is set to 0.05 seconds, then the minimum hold duration corresponds to six consecutive sampling periods. Using the above data example, the switching buffer decision module will only output the tail fin target state switching command when the boundary judgment result in the corresponding direction is consecutively true for six sampling cycles. If the boundary judgment result disappears after only two to three sampling cycles, the cumulative duration of entering the corresponding state will be cleared and the tail fin state switching will not be triggered.

[0127] The initial setting method for the current rear wing state record value is to directly assign a value based on the default control strategy at vehicle startup or the initial operating conditions corresponding to the current vehicle speed data and steering wheel angle data. As a data example, when the vehicle is initially in a straight, low-speed driving condition during startup, and the current steering amplitude corresponding to the steering wheel angle smoothing value is not greater than the preset straight-line threshold, the current rear wing state record value can be initialized to the angle-of-attack drag reduction state. When the vehicle re-enters closed-loop control, if the current operating condition already meets the steady-state cornering trend and the operating condition stability parameter is high stability, the current rear wing state record value can also be initialized to the angle-of-attack stabilization state. The initial value at the last state transition moment can be set to the system startup moment, and the initial values ​​for both the cumulative duration of angle-of-attack stabilization and the cumulative duration of angle-of-attack drag reduction are set to zero. After adopting the above initialization method, the switching buffer decision module can obtain a clear state starting point when the system starts running, avoiding the impact of an unclear state starting point on subsequent cumulative duration calculations.

[0128] To facilitate the explanation of the calculation process for the angle-of-attack stabilization and drag reduction judgment values, the following data example is provided. When the operating condition change direction parameter is a cornering trend, the angle-of-attack stabilization direction requirement value is recorded as 1, and the angle-of-attack drag reduction direction requirement value is recorded as 0; when the operating condition change intensity parameter is medium intensity, the intensity level value is recorded as 2; when the operating condition stability parameter is transitional stability, the stability level value is recorded as 1. Under the condition that the intensity weight is 0.6 and the stability weight is 0.4, the intensity weighted value is 1.2, the stability weighted value is 0.4, and the switching base value is 1.6; since the angle-of-attack stabilization direction requirement value is 1, the angle-of-attack stabilization judgment value is 1.6; since the angle-of-attack drag reduction direction requirement value is 0, the angle-of-attack drag reduction judgment value is 0.

[0129] If the current tail fin status record value is in the angle-of-attack drag reduction state, and the angle-of-attack stabilization entry boundary value is set to 1.7, and the angle-of-attack drag reduction exit boundary value is set to 1.1, then since the angle-of-attack stabilization judgment value of 1.6 has not yet reached the angle-of-attack stabilization entry boundary value of 1.7, the switching buffer decision module determines that the current operating condition is still within the switching buffer judgment area from the angle-of-attack drag reduction state to the angle-of-attack stabilization state. If the operating condition change intensity parameter corresponding to the next sampling period increases to high intensity, and the operating condition stability parameter increases to high stability, then the intensity level value becomes three, the stability level value becomes two, and the switching base value becomes 2.6. At this time, the angle-of-attack stabilization judgment value is 2.6, and the angle-of-attack drag reduction judgment value is still zero. Since the angle-of-attack stabilization judgment value is no less than the angle-of-attack stabilization entry boundary value of 1.7, and the angle-of-attack drag reduction judgment value is no greater than the angle-of-attack drag reduction exit boundary value of 1.1, the switching buffer decision module determines that the current operating condition has crossed the switching buffer judgment area from the angle-of-attack drag reduction state to the angle-of-attack stabilization state and enters the subsequent cumulative duration update stage.

[0130] To illustrate the transition from angle-of-attack stabilization to angle-of-attack drag reduction, the following data example is provided. When the operating condition change direction parameter exhibits a linear acceleration trend, the demand value for angle-of-attack stabilization is recorded as zero, and the demand value for angle-of-attack drag reduction is recorded as one. When the operating condition change intensity parameter is medium intensity, the intensity level value is recorded as two. When the operating condition stability parameter is high stability, the stability level value is recorded as two. Under the conditions of an intensity weight of 0.6 and a stability weight of 0.4, the intensity weighting value is 1.2, the stability weighting value is 0.8, and the switching base value is 2.0. Since the demand value for angle-of-attack drag reduction is one, the angle-of-attack drag reduction judgment value is 2.0. Since the demand value for angle-of-attack stabilization is zero, the angle-of-attack stabilization judgment value is zero.

[0131] If the current tail wing status record value is in the angle-of-attack stabilization state, and the angle-of-attack drag reduction entry boundary value is set to 1.6, and the angle-of-attack stabilization exit boundary value is set to 1.2, then the switching buffer decision module determines that the current operating condition has exceeded the switching buffer judgment area from the angle-of-attack stabilization state to the angle-of-attack drag reduction state. If the minimum holding time is set to 0.3 seconds and the preset sampling period is set to 0.05 seconds, then the cumulative duration of entering the angle-of-attack drag reduction state needs to be accumulated continuously for six sampling periods before the switching buffer decision module outputs the tail wing target state switching command to switch to the angle-of-attack drag reduction state. Through this setting, it is possible to avoid the tail wing switching back and forth too quickly between the angle-of-attack stabilization state and the angle-of-attack drag reduction state when the vehicle accelerates briefly after exiting a corner and then brakes rapidly again.

[0132] The continuous angle of attack generation module is used to determine the current adjustment direction based on the tail fin target state switching command, the current tail fin state record value, the working condition trend parameter set and the actual tail fin angle data, generate the corresponding target state angle of attack and the current adjustment step size, call the corresponding angle of attack change trajectory to generate the current target tail fin angle of attack periodically, and construct and output the target tail fin angle of attack sequence after executing the change amount constraint.

[0133] Furthermore, the more specific implementation of the continuous angle of attack generation module is as follows:

[0134] The continuous angle of attack generation module is used to convert the state-level adjustment result corresponding to the tail wing target state switching command into a continuously variable target tail wing angle of attack sequence, so as to avoid the tail wing from jumping directly from one state to another, causing sudden changes in angle of attack, sudden changes in aerodynamic torque and vehicle attitude disturbance.

[0135] The continuous angle of attack generation module pre-establishes the previous target's tail fin angle of attack, the current target's tail fin angle of attack, and the target angle of attack buffer. The continuous angle of attack generation module also pre-sets the following parameters: angle of attack stabilization reference value, angle of attack drag reduction reference value, stabilization base step size, drag reduction base step size, stabilization low-intensity correction angle, stabilization medium-intensity correction angle, stabilization high-intensity correction angle, stabilization low-stability correction angle, stabilization transitional stability correction angle, stabilization high-stability correction angle, drag reduction low-intensity correction angle, drag reduction medium-intensity correction angle, drag reduction high-intensity correction angle, drag reduction low-stability correction angle, drag reduction transitional stability correction angle, drag reduction high-stability correction angle, stabilization low-intensity step size correction amount, stabilization medium-intensity step size correction amount, stabilization high-intensity step size correction amount, drag reduction low-intensity step size correction amount, drag reduction medium-intensity step size correction amount, drag reduction high-intensity step size correction amount, maximum angle of attack change per unit sampling period, target angle convergence threshold, and target angle of attack buffer capacity.

[0136] It should be noted that the previous target tail fin angle of attack is used to record the target tail fin angle of attack already output in the previous sampling period, and the current target tail fin angle of attack is used to record the target tail fin angle of attack generated in the current sampling period. The target angle of attack buffer is used to store the continuously output target tail fin angles of attack in the order of sampling time, thus forming a target tail fin angle of attack sequence. The angle of attack stabilization reference value and the angle of attack drag reduction reference value represent the basic target angle of attack corresponding to the angle of attack stabilization state and the angle of attack drag reduction state, respectively; the stabilization base step size and the drag reduction base step size represent the change in the basic angle of attack corresponding to each sampling period along the stabilization adjustment direction and the drag reduction adjustment direction without additional intensity step size correction, respectively; each correction angle and each step size correction amount are preset non-negative values. In the preset, the sum of the angle of attack drag reduction reference value, the drag reduction high intensity correction angle, and the drag reduction high stability correction angle is less than the sum of the angle of attack stabilization reference value, the stabilization low intensity correction angle, and the stabilization low stability correction angle, thereby ensuring that the upper limit of the target tail fin angle of attack corresponding to the angle of attack drag reduction state is less than the lower limit of the target tail fin angle of attack corresponding to the angle of attack stabilization state. Therefore, even if both the angle-of-attack stabilization state and the angle-of-attack drag reduction state generate the target angle of attack by adding the reference value to the corresponding correction angle, the preset relationship that the target tail fin angle of attack corresponding to the angle-of-attack drag reduction state is lower than the target tail fin angle of attack corresponding to the angle-of-attack stabilization state will not be changed.

[0137] The continuous angle-of-attack generation module first determines the current adjustment direction based on the tail fin target state switching command and the current tail fin state record value. Specifically, the processing logic is as follows: when the tail fin target state switching command is to switch to the angle-of-attack stabilization state, and the current tail fin state record value is the angle-of-attack drag reduction state, the current adjustment direction is determined as the stabilization adjustment direction; when the tail fin target state switching command is to switch to the angle-of-attack drag reduction state, and the current tail fin state record value is the angle-of-attack stabilization state, the current adjustment direction is determined as the drag reduction adjustment direction; when the tail fin target state switching command is to maintain the current tail fin state, the continuous angle-of-attack generation module further reads the current tail fin state record value. If the current tail fin state record value is the angle-of-attack stabilization state, the current adjustment direction is determined as the stabilization maintenance direction; if the current tail fin state record value is the angle-of-attack drag reduction state, the current adjustment direction is determined as the drag reduction maintenance direction. Therefore, the continuous angle-of-attack generation module can obtain a clear adjustment direction in each sampling cycle, rather than directly equating the tail fin target state switching command with the target tail fin angle of attack.

[0138] After determining the current adjustment direction, the continuous angle of attack generation module selects the corresponding correction angle based on the working condition change intensity parameter and the working condition stability parameter, and generates the target state angle of attack corresponding to the current state. The specific processing logic is as follows: When the current adjustment direction is the stabilization adjustment direction or the stabilization maintenance direction, first read the angle of attack stabilization reference value; when the operating condition change intensity parameter is low intensity, take the stabilization low intensity correction angle as the stabilization intensity correction angle; when the operating condition change intensity parameter is medium intensity, take the stabilization medium intensity correction angle as the stabilization intensity correction angle; when the operating condition change intensity parameter is high intensity, take the stabilization high intensity correction angle as the stabilization intensity correction angle; when the operating condition stability parameter is low stability, take the stabilization low stability correction angle as the stabilization stability correction angle; when the operating condition stability parameter is transitional stability, take the stabilization transitional stability correction angle as the stabilization stability correction angle; when the operating condition stability parameter is high stability, take the stabilization high stability correction angle as the stabilization stability correction angle; then add the angle of attack stabilization reference value, the stabilization intensity correction angle, and the stabilization stability correction angle to obtain the angle of attack stabilization target value.

[0139] When the current adjustment direction is the drag reduction adjustment direction or the drag reduction holding direction, first read the angle of attack drag reduction reference value; when the operating condition change intensity parameter is low intensity, take the drag reduction low intensity correction angle as the drag reduction intensity correction angle; when the operating condition change intensity parameter is medium intensity, take the drag reduction medium intensity correction angle as the drag reduction intensity correction angle; when the operating condition change intensity parameter is high intensity, take the drag reduction high intensity correction angle as the drag reduction intensity correction angle; when the operating condition stability parameter is low stability, take the drag reduction low stability correction angle as the drag reduction stability correction angle; when the operating condition stability parameter is transitional stability, take the drag reduction transitional stability correction angle as the drag reduction stability correction angle; when the operating condition stability parameter is high stability, take the drag reduction high stability correction angle as the drag reduction stability correction angle; then add the angle of attack drag reduction reference value, drag reduction intensity correction angle, and drag reduction stability correction angle to obtain the angle of attack drag reduction target value.

[0140] It should be noted that the drag reduction strength correction angle and drag reduction stability correction angle are used for fine-tuning within the target angle of attack range corresponding to the angle of attack reduction state, without changing the preset relationship that the target tail fin angle of attack corresponding to the angle of attack reduction state is generally lower than the target tail fin angle of attack corresponding to the angle of attack stabilization state. Therefore, the operating condition change intensity parameter and the operating condition stability parameter are both involved in the calculation through a pre-set parameter mapping relationship.

[0141] The continuous angle of attack generation module then determines the adjustment step size corresponding to the current sampling period based on the current adjustment direction and the intensity parameter of the operating condition change. Specifically, when the current adjustment direction is the stabilization adjustment direction or the stabilization maintenance direction, the basic stabilization step size is read first. When the intensity parameter of the operating condition change is low, the low-intensity stabilization step size correction is used as the stabilization step size correction; when the intensity parameter of the operating condition change is medium, the medium-intensity stabilization step size correction is used as the stabilization step size correction; and when the intensity parameter of the operating condition change is high, the high-intensity stabilization step size correction is used as the stabilization step size correction. Finally, the basic stabilization step size and the stabilization step size correction are added to obtain the current stabilization step size. When the current adjustment direction is the drag reduction adjustment direction or the drag reduction holding direction, first read the basic drag reduction step size; when the working condition change intensity parameter is low intensity, take the low intensity drag reduction step size correction amount as the drag reduction step size correction amount; when the working condition change intensity parameter is medium intensity, take the medium intensity drag reduction step size correction amount as the drag reduction step size correction amount; when the working condition change intensity parameter is high intensity, take the high intensity drag reduction step size correction amount as the drag reduction step size correction amount; then add the basic drag reduction step size and the drag reduction step size correction amount to obtain the current drag reduction step size.

[0142] The continuous angle-of-attack generation module then calls the corresponding angle-of-attack change trajectory based on the current adjustment direction to generate the current target tail fin angle of attack for the current sampling period. Specifically, the stabilization adjustment direction and stabilization maintenance direction correspond to the stabilization angle-of-attack change trajectory, and the drag reduction adjustment direction and drag reduction maintenance direction correspond to the drag reduction angle-of-attack change trajectory. When the continuous angle-of-attack generation module first enters the control process, it uses the actual tail fin angle corresponding to the actual tail fin angle data as the previous target tail fin angle of attack. In each subsequent sampling period, it uses the current target tail fin angle of attack output from the previous sampling period as the new previous target tail fin angle of attack. When the current adjustment direction is the stabilization adjustment direction or the stabilization maintenance direction, the continuous angle-of-attack generation module adds the previous target tail fin angle of attack to the current stabilization growth rate to obtain a stabilization candidate angle of attack. If the stabilization candidate angle of attack is greater than the angle-of-attack stabilization target value, the current target tail fin angle of attack is limited to the angle-of-attack stabilization target value; if the stabilization candidate angle of attack is not greater than the angle-of-attack stabilization target value, the current target tail fin angle of attack is recorded as the stabilization candidate angle of attack. When the current adjustment direction is the drag reduction adjustment direction or the drag reduction maintenance direction, the continuous angle of attack generation module subtracts the current drag reduction step size from the previous target tail fin angle of attack to obtain a drag reduction candidate angle of attack. If the drag reduction candidate angle of attack is less than the angle of attack drag reduction target value, the current target tail fin angle of attack is limited to the angle of attack drag reduction target value; if the drag reduction candidate angle of attack is not less than the angle of attack drag reduction target value, the current target tail fin angle of attack is recorded as the drag reduction candidate angle of attack. Therefore, the continuous angle of attack generation module does not output the target state angle of attack all at once, but approximates the target state angle of attack periodically along the corresponding angle of attack change trajectory.

[0143] The continuous angle of attack generation module further constrains the change in the current target tail fin angle of attack to limit jumps in the target tail fin angle of attack within a unit sampling period. Specifically, the processing logic is as follows: first, calculate the target angle difference between the current target tail fin angle of attack and the previous target tail fin angle of attack; if the absolute value of the target angle difference is not greater than the maximum angle of attack change within a unit sampling period, then keep the current target tail fin angle of attack unchanged; if the target angle difference is positive and its absolute value is greater than the maximum angle of attack change within a unit sampling period, then correct the current target tail fin angle of attack to the previous target tail fin angle of attack plus the maximum angle of attack change within a unit sampling period; if the target angle difference is negative and its absolute value is greater than the maximum angle of attack change within a unit sampling period, then correct the current target tail fin angle of attack to the previous target tail fin angle of attack minus the maximum angle of attack change within a unit sampling period. Through this processing, it is possible to prevent the current target tail fin angle of attack from changing too rapidly due to a recent state transition or a sudden increase in the intensity parameter of the operating condition.

[0144] When the absolute value of the difference between the current target tail fin angle of attack and the corresponding target state angle of attack is not greater than the target angle convergence threshold, the continuous angle of attack generation module determines that the current target tail fin angle of attack has converged to the corresponding target state angle of attack. If the current adjustment direction is the stabilization maintenance direction, the continuous angle of attack generation module maintains the current target tail fin angle of attack equal to the angle of attack stabilization target value; if the current adjustment direction is the drag reduction maintenance direction, the continuous angle of attack generation module maintains the current target tail fin angle of attack equal to the angle of attack drag reduction target value. If the absolute value of the difference between the current target tail fin angle of attack and the corresponding target state angle of attack is greater than the target angle convergence threshold, the continuous angle of attack generation module continues to generate a new current target tail fin angle of attack along the angle of attack change trajectory corresponding to the current adjustment direction in the next sampling period.

[0145] After obtaining the current target tail fin angle of attack, the continuous angle of attack generation module writes the current target tail fin angle of attack into the target angle of attack buffer. When the number of data in the target angle of attack buffer exceeds the buffer capacity, the earliest written historical target angle of attack is deleted, so that the target angle of attack buffer continuously forms a sequence of target tail fin angles of attack arranged in the order of sampling time. The continuous angle of attack generation module sends the current target tail fin angle of attack as the control output of the current sampling period to the closed-loop vibration suppression execution module, and updates the current target tail fin angle of attack to the previous target tail fin angle of attack for the next sampling period. Thus, the closed-loop vibration suppression execution module does not receive a single discrete state switching result, but a continuously updated sequence of target tail fin angles of attack, thereby enabling stable closed-loop adjustment based on the target tail fin angle of attack sequence and the actual tail fin angle data.

[0146] In one embodiment, the angle-of-attack stabilization reference value, angle-of-attack drag reduction reference value, each correction angle, each step size correction amount, maximum angle-of-attack change per unit sampling period, and target angle convergence threshold can be set based on vehicle aerodynamic characteristic data, tail wing actuator response time, and allowable fluctuation range of vehicle attitude. The continuous angle-of-attack generation module repeatedly executes the following steps in each sampling period: reading current input data, determining the current adjustment direction, generating the target state angle of attack, determining the current adjustment step size, calling the corresponding angle-of-attack change trajectory, executing change amount constraints, and outputting the current target tail wing angle of attack, thereby continuously generating a smoothly changing sequence of target tail wing angles of attack. Because the continuous angle-of-attack generation module adds target state angle of attack generation, adjustment step size generation, angle-of-attack change trajectory calling, and change amount constraints per unit sampling period between the tail wing target state switching command and the closed-loop vibration suppression execution module, it can more effectively reduce aerodynamic torque abrupt changes and vehicle attitude disturbances caused by sudden tail wing angle of attack changes compared to directly controlling angle jumps based on state switching results. It also provides continuous, stable, and predictable target angle of attack input for subsequent closed-loop vibration suppression execution.

[0147] It should be noted that the preset data in the continuous angle of attack generation module can be determined jointly based on the vehicle aerodynamic calibration results, tail wing actuator response data, track segment working condition data, and the allowable fluctuation range of vehicle body attitude. In specific settings, the air resistance variation law, stability variation law, and actuator response time under different tail wing angles of attack are first obtained through simulation, wind tunnel test, or real vehicle test. Then, combined with the control requirements under straight acceleration, cornering braking, steady-state cornering, and cornering acceleration conditions, the target angle of attack range, step range, and change constraint range are calibrated so that the continuous angle of attack generation module can output a continuous, smooth target tail wing angle of attack sequence that meets the execution capability constraints under different working conditions.

[0148] The angle-of-attack stabilization reference value and the angle-of-attack drag reduction reference value are used to determine the basic target angle of attack corresponding to two types of control states. The angle-of-attack stabilization reference value is set by statistically analyzing the range of rear wing angles of attack that significantly improve rear axle adhesion and vehicle stability under steady-state cornering and cornering braking conditions, and selecting the value located in the middle of this range as the angle-of-attack stabilization reference value. The angle-of-attack drag reduction reference value is set by statistically analyzing the range of rear wing angles of attack that effectively reduce air resistance without causing rear wing instability under straight-line acceleration and cornering acceleration conditions, and selecting the value located in the middle of this range as the angle-of-attack drag reduction reference value. As a data example, if the experimentally obtained stable effective angle-of-attack range corresponding to the angle-of-attack stabilization state is 11 to 15 degrees, then the angle-of-attack stabilization reference value can be set to 12 degrees; if the experimentally obtained drag-reducing effective angle-of-attack range corresponding to the drag-reducing state is 2 to 5 degrees, then the angle-of-attack drag reduction reference value can be set to 3.5 degrees. Using the above data examples, the angle-of-attack stabilization state and the angle-of-attack drag reduction state have formed a clear separation at the reference angle of attack level.

[0149] The stabilization strength correction angle and stabilization stability correction angle are used for refined adjustments within the target angle of attack range corresponding to the angle of attack stabilization state. The stabilization low strength correction angle, stabilization medium strength correction angle, and stabilization high strength correction angle are set according to the speed of operating condition switching corresponding to the strength parameter of the changing operating condition, increasing sequentially from low to high strength. The stabilization low stability correction angle, stabilization transitional stability correction angle, and stabilization high stability correction angle are set according to the continuity and predictability corresponding to the stability level parameter of the operating condition, increasing sequentially from low to high stability. As a data example, the stabilization low strength correction angle can be set to 0.5 degrees, the stabilization medium strength correction angle to 1.2 degrees, and the stabilization high strength correction angle to 2.0 degrees; the stabilization low stability correction angle can be set to 0.2 degrees, the stabilization transitional stability correction angle to 0.6 degrees, and the stabilization high stability correction angle to 1 degree. Therefore, when the intensity parameter of the operating condition change is high and the stability parameter of the operating condition is high, the target value for angle of attack stabilization is 12 degrees + 2 degrees + 1 degree, which equals 15 degrees; when the intensity parameter of the operating condition change is low and the stability parameter of the operating condition is low, the target value for angle of attack stabilization is 12 degrees + 0.5 degrees + 0.2 degrees, which equals 12.7 degrees. Using the above setting method, the target value for angle of attack stabilization can continuously change within a preset range depending on the intensity parameter of the operating condition change and the stability parameter of the operating condition.

[0150] The drag reduction intensity correction angle and drag reduction stability correction angle are used for fine-tuning within the target angle of attack range corresponding to the drag reduction state. The low-intensity, medium-intensity, and high-intensity drag reduction correction angles are set according to the adjustment requirements corresponding to the intensity parameters of the changing operating conditions, increasing sequentially from low to high intensity. The low-stability, transitional stability, and high-stability drag reduction correction angles are set according to the continuity of the stability parameters corresponding to the operating conditions, increasing sequentially from low to high stability. As a data example, the low-intensity drag reduction correction angle can be set to 0.2 degrees, the medium-intensity drag reduction correction angle to 0.5 degrees, and the high-intensity drag reduction correction angle to 0.8 degrees; the low-stability drag reduction correction angle can be set to 0.1 degrees, the transitional stability drag reduction correction angle to 0.2 degrees, and the high-stability drag reduction correction angle to 0.4 degrees. Using the above data examples, when the intensity parameter of the operating condition change is high and the stability parameter is high stability, the target value for angle-of-attack drag reduction is 3.5 degrees plus 0.8 degrees plus 0.4 degrees, resulting in 4.7 degrees. When the intensity parameter of the operating condition change is low and the stability parameter is low stability, the target value for angle-of-attack drag reduction is 3.5 degrees plus 0.2 degrees plus 0.1 degrees, resulting in 3.8 degrees. Since 4.7 degrees is still less than the lower limit of the aforementioned target value for angle-of-attack stabilization, 12.7 degrees, even if both the angle-of-attack drag reduction state and the angle-of-attack stabilization state generate the target angle of attack by adding the baseline value to the corresponding correction angle, it will not disrupt the preset relationship that the target tail fin angle of attack corresponding to the angle-of-attack drag reduction state is generally lower than the target tail fin angle of attack corresponding to the angle-of-attack stabilization state.

[0151] To ensure that the upper limit of the target tail fin angle of attack corresponding to the angle-of-attack reduction state is less than the lower limit of the target tail fin angle of attack corresponding to the angle-of-attack stabilization state, the following method can be used to verify and preset each set of correction angles: First, calculate the maximum possible target value corresponding to the angle-of-attack reduction state, i.e., the angle-of-attack reduction baseline value plus the high-intensity correction angle plus the high-stability correction angle; then calculate the minimum possible target value corresponding to the angle-of-attack stabilization state, i.e., the angle-of-attack stabilization baseline value plus the low-intensity correction angle plus the low-stability correction angle; only when the maximum possible target value corresponding to the angle-of-attack reduction state is less than the minimum possible target value corresponding to the angle-of-attack stabilization state is the parameter setting deemed to meet the state interval separation requirement. Taking the aforementioned data example, the maximum possible target value corresponding to the angle-of-attack reduction state is 4.7 degrees, and the minimum possible target value corresponding to the angle-of-attack stabilization state is 12.7 degrees. Since 4.7 degrees is less than 12.7 degrees, it can be confirmed that the angle-of-attack intervals of the two types of targets do not overlap.

[0152] The stabilization base step size, drag reduction base step size, and step size corrections are used to determine the rate of angle of attack change during each sampling cycle under different operating conditions. The stabilization base step size and drag reduction base step size are set based on the minimum effective angle of attack change that the tail fin actuator can stably respond to within a single sampling cycle. The step size corrections are set according to the rate of change of the operating condition corresponding to the intensity parameter, increasing sequentially from low intensity to medium intensity and then to high intensity. As a data example, if the preset sampling cycle is set to 0.05 seconds, and the minimum effective angle of attack change that the tail fin actuator can stably execute within 0.05 seconds is 0.4 degrees, then both the stabilization base step size and the drag reduction base step size can be set to 0.4 degrees. Furthermore, the step size correction for stabilization at low intensity can be set to 0.1 degrees, for stabilization at medium intensity to 0.3 degrees, and for stabilization at high intensity to 0.5 degrees; similarly, the step size correction for drag reduction at low intensity can be set to 0.1 degrees, for drag reduction at medium intensity to 0.2 degrees, and for drag reduction at high intensity to 0.4 degrees. Thus, when the intensity parameter of the operating condition change is high, the current step size for stabilization is 0.9 degrees, and the current step size for drag reduction is 0.8 degrees; when the intensity parameter of the operating condition change is low, both the current step size for stabilization and the current step size for drag reduction are 0.5 degrees. Through these settings, the continuous angle of attack generation module can approach the target angle of attack more quickly under high intensity operating conditions and more smoothly under low intensity operating conditions.

[0153] The maximum angle-of-attack change per unit sampling period is used to limit the maximum jump in the target tail wing angle of attack within a single sampling period. The maximum angle-of-attack change per unit sampling period is set by first calculating the maximum angle change that the tail wing actuator can stably complete within one sampling period under different loads, and then, combined with the allowable fluctuation range of the vehicle attitude, taking a value no greater than the upper limit of the actuator's stable response without causing significant vehicle attitude disturbance as the maximum angle-of-attack change per unit sampling period. As a data example, if the experiment shows that the upper limit of the angle change that the tail wing actuator can stably respond to within one sampling period is 1.2 degrees, and the upper limit of the allowable angle change corresponding to the vehicle's attitude fluctuation between two adjacent sampling periods is 1.0 degrees, then the maximum angle-of-attack change per unit sampling period can be set to 1.0 degrees. Using the above data example, when the difference between the stabilization candidate angle of attack and the previous target tail wing angle of attack is 1.4 degrees, the continuous angle-of-attack generation module will correct the current target tail wing angle of attack to the previous target tail wing angle of attack plus 1.0 degrees, instead of directly outputting a jump result of 1.4 degrees.

[0154] The target angle convergence threshold is used to determine whether the current target tail wing angle of attack is sufficiently close to the corresponding target state angle of attack. The target angle convergence threshold is set based on the tail wing angle sensor resolution, the actuator angle control error, and the vehicle's sensitivity to the target angle residual. As a data example, if the tail wing angle sensor resolution is 0.05 degrees and the actuator's stability control error does not exceed 0.1 degrees, the target angle convergence threshold can be set to 0.2 degrees. Using the above data example, when the absolute value of the difference between the current target tail wing angle of attack and the angle of attack stabilization target value is not greater than 0.2 degrees, the continuous angle of attack generation module determines that the current target tail wing angle of attack has converged to the angle of attack stabilization target value; when the absolute value of the difference between the current target tail wing angle of attack and the angle of attack drag reduction target value is not greater than 0.2 degrees, the continuous angle of attack generation module determines that the current target tail wing angle of attack has converged to the angle of attack drag reduction target value.

[0155] The target angle of attack (AJ) buffer capacity is used to determine the number of consecutive historical target tail fin angles of attack that can be retained in the target AJ buffer. The target AJ buffer capacity is set based on the requirements of the subsequent closed-loop vibration suppression execution module for the length of the historical target tail fin angle of attack sequence, the preset sampling period, and the desired retention time window length. As a data example, if the preset sampling period is set to 0.05 seconds, and the target AJ buffer is expected to retain the target tail fin angle of attack sequence of the most recent second, then the target AJ buffer capacity can be set to twenty. Using the above data example, the target AJ buffer retains the target tail fin angles of attack corresponding to the most recent twenty sampling periods at any given time, thus providing the subsequent closed-loop vibration suppression execution module with a continuous, complete, and time-defined target tail fin angle of attack sequence.

[0156] To illustrate how the aforementioned preset data work together, the following data example is provided.

[0157] The preset sampling period is set to 0.05 seconds, the angle of attack stabilization reference value is set to 12 degrees, the angle of attack drag reduction reference value is set to 3.5 degrees, the stabilization low-intensity correction angle, stabilization medium-intensity correction angle, and stabilization high-intensity correction angle are set to 0.5 degrees, 1.2 degrees, and 2 degrees respectively, the stabilization low-stability correction angle, stabilization transition stability correction angle, and stabilization high-stability correction angle are set to 0.2 degrees, 0.6 degrees, and 1 degree respectively; the drag reduction low-intensity correction angle, drag reduction medium-intensity correction angle, and drag reduction high-intensity correction angle are set to 0.2 degrees, 0.5 degrees, and 0.8 degrees respectively, the drag reduction low-stability correction angle, and drag reduction transition stability correction angle are set to 0.8 degrees. The angle of attack for high stability during drag reduction is set to 0.1°, 0.2°, and 0.4°, respectively. The basic step size for both stabilization and drag reduction is set to 0.4°. The correction amounts for low-intensity, medium-intensity, and high-intensity stabilization step sizes are set to 0.1°, 0.3°, and 0.5°, respectively. The correction amounts for low-intensity, medium-intensity, and high-intensity drag reduction step sizes are set to 0.1°, 0.2°, and 0.4°, respectively. The maximum angle of attack change per unit sampling period is set to 1.0°. The target angle convergence threshold is set to 0.2°. The target angle of attack buffer capacity is set to 20.

[0158] If the current adjustment direction is the stabilization adjustment direction, the operating condition change intensity parameter is high intensity, and the operating condition stability parameter is high stability, then the target value for angle of attack stabilization is 15 degrees, and the current stabilization increment is 0.9 degrees. If the previous target tail fin angle of attack was 11 degrees, then the candidate angle of attack for stabilization is 11.9 degrees, and the current target tail fin angle of attack is recorded as 11.9 degrees. If the previous target tail fin angle of attack is updated to 14.5 degrees in the next sampling period, then the candidate angle of attack for stabilization is 15.4 degrees, which is greater than the target value for angle of attack stabilization of 15 degrees. Therefore, the current target tail fin angle of attack is limited to 15 degrees. It can be seen that the above preset data enables the target tail fin angle of attack to approach the target state angle of attack along the set trajectory in each sampling period, and automatically converges without exceeding the limit when approaching the target state angle of attack.

[0159] The closed-loop vibration suppression execution module is used to read the target tail fin angle of attack sequence and the actual tail fin angle data, calculate the angle deviation between the current target tail fin angle of attack and the current actual tail fin angle, generate a tail fin execution drive signal based on the angle deviation, and perform adaptive vibration suppression correction on the tail fin execution drive signal according to the actual tail fin angle change rate, the number of reverse corrections and the tail fin attitude fluctuation amplitude, and output the corrected tail fin execution drive signal to the tail fin actuator.

[0160] It should be noted that the closed-loop vibration suppression execution module receives the target tail fin angle of attack sequence output by the continuous angle of attack generation module, and also receives the actual tail fin angle data. The closed-loop vibration suppression execution module generates a tail fin execution drive signal based on the target tail fin angle of attack sequence and the actual tail fin angle data, and performs closed-loop suppression of tail fin attitude fluctuations, reverse corrections, and execution overshoot during execution. The preset sampling period has already been set in the aforementioned operating condition trend recognition module, and the closed-loop vibration suppression execution module directly uses this preset sampling period. The target tail fin angle of attack sequence has already been constructed in the aforementioned continuous angle of attack generation module, and the closed-loop vibration suppression execution module directly reads the current target tail fin angle of attack corresponding to the current sampling period; therefore, this module does not repeatedly preset the preset sampling period and the target tail fin angle of attack sequence.

[0161] Furthermore, a more specific implementation of the closed-loop vibration damping execution module is as follows:

[0162] The closed-loop vibration suppression execution module establishes the current target tail fin angle of attack, the current actual tail fin angle, the current angle deviation, the actual tail fin angle buffer, the angle deviation buffer, the reverse correction count value, the tail fin attitude fluctuation amplitude, and the previous tail fin execution drive signal. The current target tail fin angle of attack represents the target value corresponding to the target tail fin angle of attack sequence in the current sampling period. The current actual tail fin angle represents the actual tail fin angle data read in the current sampling period. The current angle deviation represents the difference between the current target tail fin angle of attack and the current actual tail fin angle. The actual tail fin angle buffer stores the continuously sampled actual tail fin angles in the sampling time order. The angle deviation buffer stores the continuously sampled angle deviations in the sampling time order. The previous tail fin execution drive signal represents the tail fin execution drive signal output in the previous sampling period.

[0163] The closed-loop vibration suppression execution module is pre-set with the following thresholds: execution convergence threshold, execution large deviation threshold, execution medium deviation threshold, execution high gain, execution medium gain, execution low gain, execution angular velocity threshold, reverse correction threshold, attitude fluctuation threshold, upper limit of drive change, stable hold drive value, reverse correction statistical window length, and attitude fluctuation statistical window length. Specifically, the execution convergence threshold determines whether the actual tail fin angle has converged to the current target tail fin angle of attack; the execution large deviation threshold and execution medium deviation threshold distinguish the execution gain under different deviation ranges; the execution angular velocity threshold determines whether the actual tail fin angle changes too rapidly; the reverse correction threshold determines whether frequent reverse corrections occur within the statistical window; and the attitude fluctuation threshold determines whether there is significant oscillation of the actual tail fin angle within the statistical window.

[0164] The closed-loop vibration suppression execution module reads the current target tail fin angle of attack corresponding to the current sampling period in the target tail fin angle of attack sequence in each sampling period, and reads the actual tail fin angle data corresponding to the current sampling period as the current actual tail fin angle. It then calculates the current angle deviation. Specifically, the processing logic is as follows: subtract the current actual tail fin angle from the current target tail fin angle of attack to obtain the current angle deviation; when the current angle deviation is positive, it indicates that the actual tail fin angle is lower than the current target tail fin angle of attack, and the tail fin actuator should execute in the direction of increasing angle; when the current angle deviation is negative, it indicates that the actual tail fin angle is higher than the current target tail fin angle of attack, and the tail fin actuator should execute in the direction of decreasing angle; when the current angle deviation is zero, it indicates that the current actual tail fin angle is equal to the current target tail fin angle of attack. The current actual tail fin angle is written to the actual tail fin angle buffer, and the current angle deviation is written to the angle deviation buffer. When the number of data in the actual tail fin angle buffer exceeds the number of sampling points corresponding to the attitude fluctuation statistics window length, the earliest written historical data is deleted. When the number of data in the angle deviation buffer exceeds the number of sampling points corresponding to the reverse correction statistics window length, the earliest written historical data is deleted. This ensures that the actual tail fin angle buffer and the angle deviation buffer always store continuous data that meets the requirements for calculating the actual tail fin angle change rate, attitude fluctuation statistics, and reverse correction statistics.

[0165] After obtaining the current angle deviation, the closed-loop vibration suppression execution module calculates the actual angle change rate of the tail fin. The specific processing logic is as follows: first, it reads the current actual tail fin angle corresponding to the current sampling period and the historical actual tail fin angle corresponding to the previous sampling period from the actual tail fin angle buffer; then, it subtracts the historical actual tail fin angle from the current actual tail fin angle and divides the difference by the preset sampling period to obtain the actual angle change rate of the tail fin. Further, it calculates the reverse correction count. The specific processing logic is as follows: within the time window corresponding to the reverse correction statistical window length, it compares the angle deviation directions of two adjacent sampling periods one by one; if the angle deviation of the previous sampling period is positive and the angle deviation of the next sampling period is negative, or the angle deviation of the previous sampling period is negative and the angle deviation of the next sampling period is positive, then the reverse correction count is incremented by one; if the angle deviation directions of two adjacent sampling periods are consistent, or the absolute value of the angle deviation in any sampling period is not greater than the execution convergence threshold, then the reverse correction count is not incremented. Through the above processing, the reverse correction count is used to characterize whether the tail fin frequently reverses after passing the target point during the process of approaching the current target tail fin angle of attack.

[0166] The closed-loop vibration suppression execution module simultaneously calculates the tail fin attitude fluctuation amplitude. Specifically, within the time window corresponding to the length of the attitude fluctuation statistics window, it reads all actual tail fin angles within the window from the actual tail fin angle buffer, takes the maximum and minimum values ​​of the actual tail fin angles within the window, and subtracts the minimum value from the maximum to obtain the tail fin attitude fluctuation amplitude. The tail fin attitude fluctuation amplitude is used to characterize the actual angle swing range of the tail fin within the most recent sampling periods. If the tail fin attitude fluctuation amplitude is large, it indicates that there is significant swaying, jitter, or local overshoot during tail fin execution; if the tail fin attitude fluctuation amplitude is small, it indicates that the tail fin execution process is relatively stable.

[0167] The closed-loop vibration damping execution module generates the initial tail fin execution drive signal based on this. The specific processing logic is as follows: First, the execution gain is selected based on the absolute value of the current angle deviation. When the absolute value of the current angle deviation is greater than the large deviation threshold, the high execution gain is read as the current execution gain; when the absolute value of the current angle deviation is less than or equal to the large deviation threshold but greater than the medium deviation threshold, the medium execution gain is read as the current execution gain; when the absolute value of the current angle deviation is less than or equal to the medium deviation threshold, the low execution gain is read as the current execution gain. Then, the current angle deviation is multiplied by the current execution gain to obtain the initial drive quantity. When the current angle deviation is positive, the initial drive quantity is determined as the initial tail fin execution drive signal in the direction of increasing the angle; when the current angle deviation is negative, the initial drive quantity is determined as the initial tail fin execution drive signal in the direction of decreasing the angle. Therefore, the larger the angle deviation, the larger the initial tail fin execution drive signal; the smaller the angle deviation, the smaller the initial tail fin execution drive signal, thus enabling the tail fin actuator to quickly approach the current target tail fin angle of attack during the large deviation phase and slow down the adjustment speed during the small deviation phase.

[0168] It should be noted that the flowchart of the method for generating the tail fin drive signal and performing adaptive vibration damping correction is as follows: Figure 4 As shown.

[0169] After generating the initial tail fin execution drive signal, the closed-loop vibration suppression execution module performs vibration suppression correction on the tail fin execution drive signal and determines execution convergence. Specifically, the processing logic is as follows: when the absolute value of the actual tail fin angle change rate is greater than the execution angular velocity threshold, it is determined that the current execution process has a risk of excessively rapid change; when the reverse correction count value is greater than or equal to the reverse correction threshold, it is determined that the current execution process has a risk of frequent reverse corrections; when the tail fin attitude fluctuation amplitude is greater than or equal to the attitude fluctuation threshold, it is determined that the current execution process has a significant attitude fluctuation risk. If none of the above three risks are triggered, the initial tail fin execution drive signal remains unchanged, and this initial tail fin execution drive signal is used as the current candidate tail fin execution drive signal.

[0170] If any risk is triggered, the closed-loop vibration suppression execution module adaptively adjusts the current execution gain and corrects the execution drive signal according to the risk status. Specifically, the processing logic is as follows: the current execution gain is reduced by one level; if the current execution gain is already at a low gain, it remains unchanged; the current angle deviation is then multiplied by the reduced current execution gain to regenerate the corrected drive quantity; subsequently, the corrected drive quantity is compared with the drive change amount between the previous tail fin execution drive signal and the upper limit of the drive change amount. If the absolute value of the drive change amount is greater than the upper limit of the drive change amount, the corrected drive quantity is limited to the allowable range corresponding to the upper limit of the drive change amount between the previous tail fin execution drive signal and the upper limit of the drive change amount.

[0171] The corrected drive quantity after the above processing is used as the current candidate tail fin execution drive signal. The closed-loop vibration suppression execution module further determines whether the current actual tail fin angle has met the execution convergence condition. When the absolute value of the current angle deviation is not greater than the execution convergence threshold, and the absolute value of the actual tail fin angle change rate is not greater than the execution angular velocity threshold, and the tail fin attitude fluctuation amplitude is less than the attitude fluctuation threshold, it is determined that the actual tail fin angle has converged to the current target tail fin angle of attack, and at this time, the stable holding drive value is output as the tail fin execution drive signal; when the absolute value of the current angle deviation is greater than the execution convergence threshold, or the absolute value of the actual tail fin angle change rate is greater than the execution angular velocity threshold, or the tail fin attitude fluctuation amplitude is not less than the attitude fluctuation threshold, it is determined that the actual tail fin angle has not yet converged to the current target tail fin angle of attack, and at this time, the current candidate tail fin execution drive signal is output as the tail fin execution drive signal. Thus, the closed-loop vibration suppression execution module forms a closed-loop control process that adaptively adjusts the execution gain, drive change quantity, and final output drive result according to the actual tail fin angle feedback state.

[0172] After receiving the tail fin drive signal, the closed-loop vibration suppression module outputs the current tail fin drive signal to the tail fin actuator to drive the tail fin actuator to change the actual tail fin angle. It then updates the current tail fin drive signal to the previous tail fin drive signal for the next sampling period. In the next sampling period, the closed-loop vibration suppression module rereads the updated actual tail fin angle data and continues to execute the following processes: target tail fin angle of attack reading, current angle deviation calculation, actual tail fin angle change rate calculation, reverse correction count statistics, tail fin attitude fluctuation amplitude calculation, initial tail fin drive signal generation, vibration suppression correction, adaptive control adjustment, and convergence determination. Thus, the closed-loop vibration suppression module forms a tail fin adaptive closed-loop control link with the current target tail fin angle of attack as the control target, the actual tail fin angle as the feedback quantity, and the tail fin drive signal as the control output.

[0173] It should be noted that after the closed-loop vibration suppression execution module performs the convergence determination, the output tail fin execution drive signal includes two types: the stable holding drive value and the current candidate tail fin execution drive signal. These two drive signals correspond to different control stages in the tail fin execution process. When the absolute value of the current angle deviation is not greater than the execution convergence threshold, the absolute value of the actual tail fin angle change rate is not greater than the execution angular velocity threshold, and the tail fin attitude fluctuation amplitude is less than the attitude fluctuation threshold, it indicates that the actual tail fin angle has converged to near the current target tail fin angle of attack, and the tail fin execution process has transitioned from the continuous correction stage to the stable holding stage. At this time, the stable holding drive value is output as the tail fin execution drive signal. The stable holding drive value is used to characterize the holding control quantity after the actual tail fin angle has basically reached its position. Its role is not to continue to push the actual tail fin angle to change significantly, but to maintain the stability of the current actual tail fin angle, suppress position drift caused by wind load disturbance, mechanical clearance, elastic backlash, and local vibration, thereby avoiding unnecessary repetitive actions of the tail fin near the target angle.

[0174] When the absolute value of the current angle deviation is greater than the execution convergence threshold, or the absolute value of the actual tail fin angle change rate is greater than the execution angular velocity threshold, or the tail fin attitude fluctuation amplitude is not less than the attitude fluctuation threshold, it indicates that the actual tail fin angle has not yet converged to the current target tail fin angle of attack, and the tail fin execution process is still in the continuous adjustment phase. At this time, the current candidate tail fin execution drive signal is output as the tail fin execution drive signal. The current candidate tail fin execution drive signal is not the unprocessed raw drive quantity, but a dynamically corrected control quantity obtained by processing the initial tail fin execution drive signal through risk judgment, adaptive execution gain adjustment, and drive change amount constraint. The current candidate tail fin execution drive signal is used to continuously eliminate the current angle deviation in the non-convergence phase and push the actual tail fin angle closer to the current target tail fin angle of attack. At the same time, by limiting the drive change amplitude and reducing the execution gain, it suppresses excessively rapid changes, overshoot, yaw, and repeated oscillations during the execution process.

[0175] Therefore, although both the stable hold drive value and the current candidate tail fin execution drive signal are output to the tail fin actuator as tail fin execution drive signals, the control states they represent are different. The stable hold drive value represents the tail fin actuator's holding control state near the target angle, while the current candidate tail fin execution drive signal represents the tail fin actuator's dynamic correction control state before reaching the target angle. The former emphasizes stable holding near the target angle, while the latter emphasizes continuous approach in the target angle direction. By distinguishing between the non-converged stage and the converged stage during tail fin execution and outputting the current candidate tail fin execution drive signal and the stable hold drive value respectively, this invention can suppress overshoot, yaw, jitter, and repetitive actions of the tail fin near the target point while ensuring the target tail fin angle of attack tracking capability, thereby solving the technical problems of easy oscillation, unstable execution, and frequent repetitive actions of the mechanism in the prior art during tail fin execution.

[0176] In one embodiment, the switching buffer decision module and the continuous angle of attack generation module can be deployed in the vehicle-mounted embedded control unit of the electric vehicle and interact with the networked data acquisition unit via the vehicle network. After receiving local sampled data and network-synchronized data, the vehicle-mounted embedded control unit updates and manages the two types of data in chronological order, using the latest valid data as the input for tail wing state switching determination and target angle of attack generation. By combining the latest data acquired via the network with the vehicle-mounted embedded control link, this invention can improve the data integrity, condition identification accuracy, and execution stability of tail wing control under complex dynamic operating conditions of electric vehicles, thereby providing stronger scene adaptability for active aerodynamic control of electric vehicles.

[0177] It should be noted that the execution convergence threshold, execution large deviation threshold, execution medium deviation threshold, execution high gain, execution medium gain, execution low gain, execution angular velocity threshold, reverse correction threshold, attitude fluctuation threshold, upper limit of drive change, stable holding drive value, reverse correction statistical window length, and attitude fluctuation statistical window length can be set according to the tail wing actuator response time, tail wing angle sensor resolution, mechanical transmission backlash, track wind load disturbance level, and allowable fluctuation range of vehicle attitude. The closed-loop vibration suppression execution module repeats the following sequence in each sampling cycle: reading the current target tail wing angle of attack and the current actual tail wing angle, calculating the current angle deviation, calculating the actual tail wing angle change rate, statistically analyzing the reverse correction count value, calculating the tail wing attitude fluctuation amplitude, generating the initial tail wing execution drive signal, executing vibration suppression correction, executing adaptive control adjustment, determining the execution convergence condition, and outputting the tail wing execution drive signal. Because the closed-loop vibration suppression execution module adds angle deviation closed-loop feedback, reverse correction identification, attitude fluctuation identification and adaptive vibration suppression control between the target tail fin angle of attack sequence and the tail fin actuator, it can more effectively suppress overshoot, yaw and high-frequency jitter during tail fin execution compared to the method of directly outputting the execution signal according to the target angle, and improve the tracking stability and execution reliability of the actual tail fin angle to the target tail fin angle of attack sequence.

[0178] The preset data in the closed-loop vibration damping execution module can be jointly set based on the response time of the tail wing actuator, the resolution of the tail wing angle sensor, the mechanical transmission clearance, the wind load disturbance level, and the allowable fluctuation range of the vehicle attitude. Specifically, the target tail wing angle of attack, actual tail wing angle, angle deviation, actual tail wing angle change rate, and drive output changes during tail wing execution are first collected in both bench and real vehicle environments. Then, the stability error range, overshoot amplitude, sway frequency, and angle fluctuation range of the tail wing when approaching the target angle are statistically analyzed. Subsequently, deviation grading thresholds and execution gains are set based on the response capability of the tail wing actuator in different deviation ranges. Furthermore, execution angular velocity thresholds, reverse correction thresholds, and attitude fluctuation thresholds are set based on the upper limit of angular velocity when overshoot occurs, the upper limit of reverse correction times, and the upper limit of attitude fluctuation. Finally, the upper limit of drive change is set based on the allowable single-cycle drive jump variable of the actuator. Therefore, the aforementioned preset data are not arbitrarily given, but are determined jointly based on the actual response characteristics of the tail wing execution link and the allowable attitude fluctuation range of the vehicle.

[0179] The convergence threshold, large deviation threshold, and medium deviation threshold are used to divide the tail fin execution process into convergence, small deviation, medium deviation, and large deviation zones. The convergence threshold is set by first determining the maximum allowable residual angle deviation when the tail fin is essentially in position, based on the tail fin angle sensor resolution and the upper limit of the actuator's stable control error. This maximum residual angle deviation is then set as the convergence threshold. For example, if the tail fin angle sensor resolution is 0.05 degrees and the upper limit of the actuator's angle error under stable control is 0.15 degrees, the convergence threshold can be set to 0.2 degrees. The medium deviation threshold and large deviation threshold are set segmentally based on the actuator's tracking capability within different deviation ranges, ensuring that the large deviation threshold is greater than the medium deviation threshold, and the medium deviation threshold is greater than the convergence threshold. For example, the medium deviation threshold can be set to 1.0 degrees, and the large deviation threshold to 3.0 degrees. Using the above data examples, when the absolute value of the current angle deviation is greater than 3.0 degrees, the tail fin is in the large deviation rapid approach zone; when the absolute value of the current angle deviation is greater than 1.0 degrees but not greater than 3.0 degrees, the tail fin is in the medium deviation stable adjustment zone; when the absolute value of the current angle deviation is greater than 0.2 degrees but not greater than 1.0 degrees, the tail fin is in the small deviation fine correction zone; when the absolute value of the current angle deviation is not greater than 0.2 degrees, the tail fin enters the execution convergence zone.

[0180] High gain, medium gain, and low gain are used to generate tail fin drive signals of varying intensities based on different deviation ranges. These values ​​are set sequentially based on the stable response speed of the actuator under large, medium, and small deviation conditions, ensuring that high gain is greater than medium gain, and medium gain is greater than low gain. If the tail fin drive signal uses a normalized drive quantity, and the drive quantity ranges from -1 to +1, then high gain, medium gain, and low gain can be set to 0.20, 0.12, and 0.06, respectively. Using the above data example, when the current angle deviation is four degrees, the initial tail fin drive signal is 0.8; when the current angle deviation is two degrees, the initial tail fin drive signal is 0.24; and when the current angle deviation is 0.5 degrees, the initial tail fin drive signal is 0.03. Therefore, the tail fin can quickly approach the target angle during large deviation phases and reduce drive intensity and mitigate overshoot risk when approaching the target point during small deviation phases.

[0181] The execution angular velocity threshold is used to determine whether the actual angle change of the tail fin is too rapid. It is set by first calculating the upper limit of the stable angular velocity of the tail fin actuator without causing significant overshoot or yaw, and then setting this upper limit as the execution angular velocity threshold. As a data example, if experimental statistics show that the upper limit of the tail fin's angular velocity when stably approaching the target angle is 18 degrees per second, then the execution angular velocity threshold can be set to 18 degrees per second. Using this data example, when the absolute value of the actual angle change rate of the tail fin exceeds 18 degrees per second, the closed-loop vibration suppression execution module determines that the current execution process has a risk of excessively rapid change and enters a process of reducing execution gain and re-correcting the drive quantity.

[0182] The reverse correction threshold and the reverse correction statistical window length are used to determine whether the tail fin frequently crosses the target point and reverses its direction within a short period of time. The reverse correction statistical window length is set based on the shortest duration required for the tail fin actuator to transition from the approach phase to the oscillation phase near the target point. As a data example, if the preset sampling period is 0.05 seconds, and experiments show that the oscillation phenomenon near the target point usually appears within 0.3 seconds, then the reverse correction statistical window length can be set to six sampling periods. The reverse correction threshold is set based on the maximum number of reverse corrections allowed within this time window. As a data example, the reverse correction threshold can be set to two. Using the above data example, if the angular deviation direction changes from positive to negative or vice versa twice or more within six consecutive sampling periods, the closed-loop vibration suppression execution module determines that the current execution process has a risk of frequent reverse corrections.

[0183] The attitude fluctuation threshold and the attitude fluctuation statistical window length are used to determine whether there is significant oscillation of the tail fin near the target angle. The attitude fluctuation statistical window length is set based on the typical time span between the tail fin's first drive correction and the next stabilization feedback. As a data example, if the previously preset sampling period is 0.05 seconds, and experiments show that the period of a local oscillation is approximately 0.4 seconds, then the attitude fluctuation statistical window length can be set to eight sampling periods. The attitude fluctuation threshold is set based on the maximum allowable difference between the maximum and minimum actual tail fin angles within this time window. As a data example, the attitude fluctuation threshold can be set to 0.6 degrees. Using the above data example, if the difference between the maximum and minimum actual tail fin angles is greater than or equal to 0.6 degrees within eight consecutive sampling periods, the closed-loop vibration suppression execution module determines that there is a significant attitude fluctuation risk in the current execution process.

[0184] The upper limit of the drive change is used to limit the maximum change amplitude of the tail wing's drive signal between two adjacent sampling periods. It is set based on the single-cycle drive jump allowed by the actuator control circuit and the vehicle's attitude sensitivity to rapid tail wing movements. If the tail wing's drive signal is represented by a normalized drive quantity, the upper limit of the drive change can be set to 0.15. Using the above data example, if the previous tail wing drive signal was 0.20, and the newly generated corrected drive quantity is 0.40, the difference between the two is 0.20, which is greater than the upper limit of 0.15. Therefore, the closed-loop vibration damping actuator module limits the corrected drive quantity to 0.35. This avoids excessive jumps in the drive signal within a single sampling period.

[0185] The stabilization drive value is used to maintain the stability of the tail fin's current position after its actual angle has converged to the target tail fin angle of attack. The stabilization drive value is determined by considering whether the tail fin actuator has a self-locking capability, whether there is a tendency to regress under wind load conditions, and the minimum maintaining drive force required to maintain the current position. If the tail fin actuator has a self-locking capability, the stabilization drive value can be set to zero; if the tail fin actuator has a slight tendency to regress under wind load disturbances, the stabilization drive value can be set to a non-zero value less than the drive amount corresponding to low gain. As a data example, in actuators with self-locking capability, the stabilization drive value can be set to zero; in actuators without self-locking capability and with a slight tendency to regress, the stabilization drive value can be set to 0.02. Using the above data example, the tail fin no longer continuously outputs a large dynamic correction drive amount during the convergence phase, but instead outputs a small holding drive amount, thereby suppressing repetitive movements near the target point.

[0186] To illustrate how the aforementioned preset data work together, the following data example is provided:

[0187] The preset sampling period is 0.05 seconds, the convergence threshold is set to 0.2 degrees, the mid-range deviation threshold is set to 1.0 degrees, the large deviation threshold is set to 3.0 degrees, the high gain, mid-range gain, and low gain are set to 0.20, 0.12, and 0.06 respectively, the angular velocity threshold is set to 18 degrees per second, the reverse correction statistical window length is set to six sampling periods, the reverse correction threshold is set to 2, the attitude fluctuation statistical window length is set to eight sampling periods, the attitude fluctuation threshold is set to 0.6 degrees, the upper limit of the drive change is set to 0.15, and the stable hold drive value is set to zero. If the current angle deviation is 2.5 degrees, since the absolute value of the current angle deviation is greater than the mid-range deviation threshold but not greater than the large deviation threshold, the mid-range gain of 0.12 is selected, and the initial tail fin drive signal of 0.30 is generated. If the actual tail fin angle change rate is 20 degrees per second, indicating a risk of excessively rapid change, the closed-loop vibration suppression execution module will reduce the current execution gain from the medium execution gain to the low execution gain and regenerate a corrected drive value of 0.15. If the previous tail fin execution drive signal was 0.05, the difference between the corrected drive value and the previous tail fin execution drive signal is 0.10, which does not exceed the upper limit of the drive change amount. Therefore, 0.15 is used as the current candidate tail fin execution drive signal. If the current angle deviation decreases to 0.15 degrees, the actual tail fin angle change rate decreases to 10 degrees per second, and the tail fin attitude fluctuation amplitude decreases to 0.4 degrees in the next sampling period, then since the absolute value of the current angle deviation is not greater than the execution convergence threshold, the absolute value of the actual tail fin angle change rate is not greater than the execution angular velocity threshold, and the tail fin attitude fluctuation amplitude is less than the attitude fluctuation threshold, the closed-loop vibration suppression execution module outputs a stable drive value of zero as the tail fin execution drive signal.

[0188] Example 2:

[0189] Please see Figure 2 As shown, this embodiment provides an intelligent electronically controlled adjustable tail fin adaptive control method, including:

[0190] Based on vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data, a set of operating condition trend parameters is generated.

[0191] Based on the set of operating condition trend parameters, the angle of attack stabilization judgment value and the angle of attack drag reduction judgment value are generated. A tail fin state switching buffer judgment system is constructed. The system performs an out-of-bounds judgment based on the current tail fin state record value. Combined with the cumulative duration of entering the corresponding state and the shortest holding time, the system outputs the tail fin target state switching command or maintains the current tail fin state unchanged.

[0192] Based on the tail fin target state switching command, the current tail fin state record value, the working condition trend parameter set and the actual tail fin angle data, the current adjustment direction is determined, the corresponding target state angle of attack and the current adjustment step size are generated, the corresponding angle of attack change trajectory is called to generate the current target tail fin angle of attack in each sampling period, and the target tail fin angle of attack sequence is constructed and output after executing the change amount constraint;

[0193] The target tail fin angle of attack sequence and the actual tail fin angle data are read, the angle deviation between the current target tail fin angle of attack and the current actual tail fin angle is calculated, a tail fin execution drive signal is generated based on the angle deviation, and an adaptive vibration suppression correction is performed on the tail fin execution drive signal according to the actual tail fin angle change rate, the number of reverse corrections and the tail fin attitude fluctuation amplitude, and the corrected tail fin execution drive signal is output to the tail fin actuator.

[0194] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

[0195] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A smart electronically controlled adjustable tail fin adaptive control method, characterized in that, include: Based on vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data, a set of operating condition trend parameters is generated. Based on the set of operating condition trend parameters, the angle of attack stabilization judgment value and the angle of attack drag reduction judgment value are generated. A tail fin state switching buffer judgment system is constructed. The system performs an out-of-bounds judgment based on the current tail fin state record value. Combined with the cumulative duration of entering the corresponding state and the shortest holding time, the system outputs the tail fin target state switching command or maintains the current tail fin state unchanged. Based on the tail fin target state switching command, the current tail fin state record value, the working condition trend parameter set and the actual tail fin angle data, the current adjustment direction is determined, the corresponding target state angle of attack and the current adjustment step size are generated, the corresponding angle of attack change trajectory is called to generate the current target tail fin angle of attack in each sampling period, and the target tail fin angle of attack sequence is constructed and output after executing the change amount constraint; The target tail fin angle of attack sequence and the actual tail fin angle data are read, the angle deviation between the current target tail fin angle of attack and the current actual tail fin angle is calculated, a tail fin execution drive signal is generated based on the angle deviation, and an adaptive vibration suppression correction is performed on the tail fin execution drive signal according to the actual tail fin angle change rate, the number of reverse corrections and the tail fin attitude fluctuation amplitude, and the corrected tail fin execution drive signal is output to the tail fin actuator.

2. The intelligent electronically controlled adjustable tail fin adaptive control method according to claim 1, characterized in that, The calculation methods for angle deviation, actual tail fin angle change rate, number of reverse corrections, and tail fin attitude fluctuation amplitude include: Read the current target tail fin angle of attack and the current actual tail fin angle corresponding to the current sampling period, and subtract the current actual tail fin angle from the current target tail fin angle of attack to obtain the current angle deviation; Write the current actual tail fin angle into the actual tail fin angle buffer, and write the current angle deviation into the angle deviation buffer; The rate of change of the actual tail fin angle is calculated based on the continuous actual tail fin angles in the actual tail fin angle buffer area. The number of reverse corrections is counted based on the continuous angle deviations in the angle deviation buffer area. The tail fin attitude fluctuation amplitude is calculated based on the continuous actual tail fin angles in the actual tail fin angle buffer area.

3. The intelligent electronically controlled adjustable tail fin adaptive control method according to claim 1, characterized in that, The methods for generating tail fin drive signals and performing adaptive vibration damping corrections include: The corresponding execution gain is selected based on the absolute value of the current angle deviation, and the current angle deviation is multiplied by the current execution gain to generate the initial tail fin execution drive signal; Determine if any of the following risks exist: the risk of excessively rapid change in the actual angle of the tail fin exceeding the execution angular velocity threshold; the risk of frequent reverse corrections where the reverse correction count is greater than or equal to the reverse correction threshold; or the risk of significant attitude fluctuations where the tail fin attitude fluctuation amplitude is greater than or equal to the attitude fluctuation threshold. If present, reduce the current execution gain and regenerate the corrected drive quantity based on the reduced current execution gain and the current angle deviation; compare the drive change between the corrected drive quantity and the previous tail fin execution drive signal, and when the absolute value of the drive change is greater than the upper limit of the drive change, apply a change limit to the corrected drive quantity; use the corrected drive quantity after change limit as the current candidate tail fin execution drive signal. If it does not exist, the initial tail fin drive signal will be used as the current candidate tail fin drive signal.

4. The intelligent electronically controlled adjustable tail fin adaptive control method according to claim 3, characterized in that, Methods for outputting tail fin actuation drive signals to the tail fin actuator include: When the absolute value of the current angle deviation is not greater than the execution convergence threshold, the absolute value of the actual angle change rate of the tail fin is not greater than the execution angular velocity threshold, and the tail fin attitude fluctuation amplitude is less than the attitude fluctuation threshold, the stable holding drive value will be output as the tail fin execution drive signal to the tail fin actuator. When the absolute value of the current angle deviation is greater than the execution convergence threshold, or the absolute value of the actual angle change rate of the tail fin is greater than the execution angular velocity threshold, or the tail fin attitude fluctuation amplitude is not less than the attitude fluctuation threshold, the current candidate tail fin execution drive signal is output as the tail fin execution drive signal to the tail fin actuator.

5. The intelligent electronically controlled adjustable tail fin adaptive control method according to claim 1, characterized in that, The methods for generating the current adjustment direction include: Read the tail fin target status switching command and the current tail fin status record value; When the tail fin target state switching command is to switch to angle of attack stabilization state and the current tail fin state record value is angle of attack drag reduction state, the current adjustment direction is determined to be the stabilization adjustment direction; When the tail fin target state switching command is to switch to angle of attack drag reduction state and the current tail fin state record value is angle of attack stabilization state, the current adjustment direction is determined to be the drag reduction adjustment direction; When the tail fin target state switching command is to maintain the current tail fin state and the current tail fin state record value is the angle of attack stabilization state, the current adjustment direction is determined to be the stabilization maintenance direction. When the tail fin target state switching command is to maintain the current tail fin state and the current tail fin state record value is the angle of attack drag reduction state, the current adjustment direction is determined to be the drag reduction maintenance direction.

6. The intelligent electronically controlled adjustable tail fin adaptive control method according to claim 5, characterized in that, The methods for generating the target state angle of attack and the current adjustment step size include: When the current adjustment direction is the stabilization adjustment direction or the stabilization maintenance direction, the angle of attack stabilization reference value is read, the stabilization intensity correction angle is selected according to the operating condition change intensity parameter, the stabilization stability correction angle is selected according to the operating condition stability parameter, and the angle of attack stabilization target value is generated based on the angle of attack stabilization reference value, the stabilization intensity correction angle, and the stabilization stability correction angle; the stabilization step size correction amount is selected according to the operating condition change intensity parameter, and the current stabilization step size is generated based on the stabilization base step size and the stabilization step size correction amount, which is used as the current adjustment step size; When the current adjustment direction is the drag reduction adjustment direction or the drag reduction holding direction, read the angle of attack drag reduction reference value, select the drag reduction intensity correction angle according to the working condition change intensity parameter, select the drag reduction stability correction angle according to the working condition stability parameter, and generate the angle of attack drag reduction target value based on the angle of attack drag reduction reference value, drag reduction intensity correction angle and drag reduction stability correction angle; select the drag reduction step size correction amount according to the working condition change intensity parameter, and generate the current drag reduction step size based on the drag reduction base step size and drag reduction step size correction amount, which is used as the current adjustment step size.

7. The intelligent electronically controlled adjustable tail fin adaptive control method according to claim 6, characterized in that, Methods for generating the current target tail fin angle of attack, constructing the target tail fin angle of attack sequence, and outputting it include: When the current adjustment direction is a stabilization adjustment direction or a stabilization maintenance direction, the previous target tail fin angle of attack is added to the current adjustment step size to obtain a stabilization candidate angle of attack. If the stabilization candidate angle of attack is greater than the angle of attack stabilization target value, the current target tail fin angle of attack is limited to the angle of attack stabilization target value. When the current adjustment direction is a drag reduction adjustment direction or a drag reduction maintenance direction, the previous target tail fin angle of attack is subtracted from the current adjustment step size to obtain a drag reduction candidate angle of attack. If the drag reduction candidate angle of attack is less than the angle of attack drag reduction target value, the current target tail fin angle of attack is limited to the angle of attack drag reduction target value. Compare the target angle difference between the current target tail fin angle of attack and the previous target tail fin angle of attack, and when the absolute value of the target angle difference is greater than the maximum angle of attack change per unit sampling period, apply a change constraint to the current target tail fin angle of attack; write the constrained current target tail fin angle of attack into the target angle of attack buffer, construct the target tail fin angle of attack sequence and output it.

8. The intelligent electronically controlled adjustable tail fin adaptive control method according to claim 1, characterized in that, The methods for obtaining the angle-of-attack stabilization judgment value and the angle-of-attack drag reduction judgment value include: Numerical conversion is performed on the parameters of working condition change direction, working condition change intensity, and working condition stability. When the working condition change direction parameter is a curve entry trend or a steady-state curve over trend, the demand value of the angle of attack stabilization direction is recorded as one, and the demand value of the angle of attack drag reduction direction is recorded as zero. When the direction parameter of the working condition change is a straight acceleration trend or a corner exit trend, the demand value of the angle of attack stabilization direction is recorded as zero, and the demand value of the angle of attack drag reduction direction is recorded as one. Multiply the strength level value by the strength weight to obtain the strength weighted value, multiply the stability level value by the stability weight to obtain the stability weighted value, add the strength weighted value and the stability weighted value to obtain the switching base value, and multiply them by the angle of attack stabilization direction requirement value and the angle of attack drag reduction direction requirement value respectively to generate the angle of attack stabilization judgment value and the angle of attack drag reduction judgment value.

9. The intelligent electronically controlled adjustable tail fin adaptive control method according to claim 8, characterized in that, Methods for outputting tail fin target state switching commands or maintaining the current tail fin state include: Construct a switching buffer decision region for switching from angle-of-attack drag reduction state to angle-of-attack stabilization state, and a switching buffer decision region for switching from angle-of-attack stabilization state to angle-of-attack drag reduction state; When the current tail fin state record value is angle of attack and drag reduction state, and the angle of attack stabilization judgment value is not less than the angle of attack stabilization entry boundary value and the angle of attack and drag reduction judgment value is not greater than the angle of attack and drag reduction exit boundary value, the duration of entering the angle of attack and stabilization state is accumulated, and when the duration is not less than the shortest holding time, the tail fin target state switching command to switch to the angle of attack and stabilization state is output. When the current tail fin state record value is angle of attack stabilization state, and the angle of attack drag reduction judgment value is not less than the angle of attack drag reduction entry boundary value and the angle of attack stabilization judgment value is not greater than the angle of attack stabilization exit boundary value, the duration of entering the angle of attack drag reduction state is accumulated, and when the duration is not less than the shortest holding time, the tail fin target state switching command to switch to the angle of attack drag reduction state is output. If the above conditions are not met, maintain the current tail fin configuration.

10. The intelligent electronically controlled adjustable tail fin adaptive control method according to claim 1, characterized in that, The method for generating the set of operating condition trend parameters includes: Based on the smoothed values ​​of vehicle speed, brake pedal opening, steering wheel angle, and actual rear wing angle corresponding to the current sampling period, as well as the historical smoothed values ​​corresponding to several sampling periods in the past historical comparison period, calculate the rate of change of vehicle speed, brake pedal opening, absolute value of steering wheel angle, and actual rear wing angle. Based on the comparison relationship between each rate of change and the corresponding increase threshold and decrease threshold, the direction of vehicle speed change, the direction of brake pedal opening change, the direction of steering input change, and the direction of tail wing attitude change are determined; each direction of change is compared with adjacent sampling periods within the current time window to obtain the direction consistency count value, direction reversal count value, and stability maintenance count value, and the direction consistency degree, direction fluctuation degree, and stability maintenance degree are generated. The parameters for the direction of change of operating conditions, the intensity of change of operating conditions, and the degree of stability of operating conditions are generated by combining the current steering amplitude, and a set of operating condition trend parameters is constructed.

11. An intelligent electronically controlled adjustable tail fin adaptive control system, used to implement the intelligent electronically controlled adjustable tail fin adaptive control method according to any one of claims 1-10, characterized in that, include: The operating condition trend recognition module generates a set of operating condition trend parameters based on vehicle speed data, brake pedal opening data, steering wheel angle data, and actual rear wing angle data. The switching buffer decision module is used to generate angle of attack stabilization judgment value and angle of attack drag reduction judgment value based on the working condition trend parameter set, construct the tail fin state switching buffer judgment system, and perform out-of-bounds judgment according to the current tail fin state record value. Combining the cumulative duration of entering the corresponding state and the shortest holding time, it outputs the tail fin target state switching command or maintains the current tail fin state unchanged. The continuous angle of attack generation module is used to determine the current adjustment direction based on the tail fin target state switching command, the current tail fin state record value, the working condition trend parameter set and the actual tail fin angle data, generate the corresponding target state angle of attack and the current adjustment step size, call the corresponding angle of attack change trajectory to generate the current target tail fin angle of attack in sampling period, and construct and output the target tail fin angle of attack sequence after executing the change amount constraint. The closed-loop vibration suppression execution module is used to read the target tail fin angle of attack sequence and the actual tail fin angle data, calculate the angle deviation between the current target tail fin angle of attack and the current actual tail fin angle, generate a tail fin execution drive signal based on the angle deviation, and perform adaptive vibration suppression correction on the tail fin execution drive signal according to the actual tail fin angle change rate, the number of reverse corrections and the tail fin attitude fluctuation amplitude, and output the corrected tail fin execution drive signal to the tail fin actuator.

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