Abs real-time adaptive control method and system based on wheel hub sensing signal fusion

Abstract

The application discloses an ABS real-time self-adaptive control method and system based on hub sensing signal fusion and relates to the field of automobile safety control.The method comprises the following steps: S1, synchronously collecting multi-source hub sensing signals of each wheel; S2, calculating a hub response coupling factor based on the multi-source hub sensing signals; S3, calculating an instantaneous slip rate based on the coupling factor and wheel speed in combination with vehicle dynamic parameters; S4, calculating a normal load based on wheel speed, braking torque and tangential acceleration in combination with the coupling factor and the instantaneous slip rate; S5, calculating an adhesion coefficient according to the instantaneous slip rate, the normal load and the wheel speed; S6, calculating the total adhesion capacity according to a slip rate deviation in combination with the coupling factor to generate a fusion weight; and S7, calculating a target braking force according to the adhesion coefficient, the normal load, the slip rate and the total adhesion capacity to adjust the wheel braking intensity.Through real-time monitoring of the wheel state, accurate control of the slip rate and optimization of the braking force distribution, the response accuracy and stability of the ABS system are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of automobile safety control, specifically an ABS real-time adaptive control method and system based on wheel hub sensor signal fusion. BACKGROUND

[0002] With the development of the automobile industry, the performance of the braking system has become a key factor in ensuring vehicle safety. The anti-lock braking system (ABS) improves the stability and handling of vehicles by preventing wheel lock during emergency braking. However, the performance of traditional ABS systems in complex road conditions still has room for improvement, mainly due to the lack of real-time adaptability to different driving conditions and road conditions.

[0003] Current ABS systems typically rely on single wheel sensor signals such as wheel speed and braking torque to control braking. However, these systems fail to fully utilize the interrelationships between wheel hub sensor signals and do not take into account dynamic changes. In addition, existing methods are mostly static control strategies, which are difficult to cope with the changing road conditions and adhesion in actual driving.

[0004] To solve this problem, an ABS real-time adaptive control method based on wheel hub sensor signal fusion is proposed. This method synchronously collects multi-source sensor signals, combines the dynamic response characteristics of the wheels and real-time road condition data, and performs accurate ABS control. At the same time, using adaptive slip rate adjustment mechanism and whole vehicle adhesion capability evaluation, dynamic control in different driving conditions is realized, and the stability and response ability of the ABS system are improved. SUMMARY

[0005] Based on the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide an ABS real-time adaptive control method and system based on wheel hub sensor signal fusion to solve the above technical problems.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solution: an ABS real-time adaptive control method based on wheel hub sensor signal fusion, comprising:

[0007] S1: synchronously collecting multi-source wheel hub sensor signals of each wheel, the multi-source wheel hub sensor signals including wheel speed signals, radial acceleration signals, tangential acceleration signals and braking torque signals;

[0008] S2: calculating wheel hub response coupling factors based on the multi-source wheel hub sensor signals;

[0009] S3: calculating the instantaneous slip rate of the wheels based on the wheel hub response coupling factors and the wheel speed signals, combined with the vehicle longitudinal speed and the tire rolling radius;

[0010] S4: Based on the wheel speed signal, the brake torque signal and the tangential acceleration signal, the normal load of the wheel is calculated in combination with the hub response coupling factor and the instantaneous slip rate;

[0011] S5: The adhesion coefficient of the wheel is calculated according to the instantaneous slip rate, the normal load and the wheel speed signal;

[0012] S6: The fusion weight is generated according to the deviation of the instantaneous slip rate of each wheel and the preset target slip rate in combination with the hub response coupling factor, and the whole vehicle adhesion capacity is calculated;

[0013] S7: The target brake force is calculated according to the adhesion coefficient of each wheel, the normal load, the instantaneous slip rate and the whole vehicle adhesion capacity, and the brake intensity of each wheel is adjusted according to the target brake force.

[0014] The application is further provided that the S2 comprises:

[0015] The wheel speed signal, the radial acceleration signal, the tangential acceleration signal and the brake torque signal of each wheel hub position are synchronously collected by a sensor;

[0016] The acceleration characteristics of the dynamic change of the wheel speed are extracted according to the time sequence difference operation of the wheel speed signal;

[0017] The hub radial vibration intensity characteristics are calculated based on the differential cumulative amount of the radial acceleration signal;

[0018] The torque and acceleration coupling characteristics are generated according to the absolute value of the product of the tangential acceleration signal and the brake torque signal;

[0019] The hub response coupling factor is calculated by comprehensively considering the acceleration characteristics, the vibration intensity characteristics and the coupling characteristics.

[0020] The application is further provided that the S3 comprises:

[0021] The collected wheel speed signal is dynamically corrected by using the hub response coupling factor;

[0022] The corrected wheel speed signal, the vehicle longitudinal speed and the tire rolling radius are mapped by a nonlinear function to calculate the instantaneous slip rate of each wheel.

[0023] The application is further provided that the S4 comprises:

[0024] The brake torque signal, the absolute value of the tangential acceleration signal and the absolute value of the wheel speed signal corrected by the hub response coupling factor are weighted and superimposed to generate a composite basic load term;

[0025] The time-varying compression index is calculated in combination with the wheel speed signal difference value, the brake torque signal difference value and the instantaneous slip rate difference value;

[0026] The normal load of the wheel is calculated based on a composite basis load term and a time-varying compression index.

[0027] The application is further configured to include the following steps:

[0028] A difference measure function is constructed based on the difference between the current instantaneous slip ratio and the historical instantaneous slip ratio, and an adhesion mapping factor is generated;

[0029] An absolute difference value between the normal load of the wheel at the current time and the previous time is calculated to obtain a load variation compensation factor;

[0030] Based on the wheel speed signal, the instantaneous slip ratio and the normal load of the wheel, the adhesion mapping factor and the load variation compensation factor, the adhesion coefficient of the wheel is calculated.

[0031] The application is further configured to include the following steps:

[0032] A slip convergence degree is generated through an exponential decay characteristic based on the absolute value of the deviation of the instantaneous slip ratio of each wheel from the preset target slip ratio;

[0033] The slip convergence degree and the hub response coupling factor are multiplied to generate a fusion weight of each wheel;

[0034] The adhesion capacity of the whole vehicle is calculated by taking the adhesion coefficient of each wheel as a base value and combining the corresponding fusion weight.

[0035] The application is further configured to include the following steps:

[0036] A control slip rate reference value is calculated based on the difference between the adhesion capacity of the whole vehicle and the preset reference adhesion capacity, and the preset target slip rate;

[0037] A slip error influence term with a decay characteristic is constructed according to the absolute value of the deviation of the control slip rate reference value from the instantaneous slip rate;

[0038] A brake force mutation suppression term with an S-shaped saturation characteristic is constructed based on the difference between the maximum allowable brake force and the brake force at the previous time;

[0039] The target brake force is obtained by nonlinearly combining the adhesion coefficient of the wheel, the normal load, the slip error influence term and the brake force mutation suppression term.

[0040] The application is further configured to calculate a slip rate error accumulation index based on the deviation between the control slip rate reference value and the instantaneous slip rate of each wheel, and combine the adhesion coefficient of each wheel and the hub response coupling factor;

[0041] When the slip rate error accumulation index is greater than a preset error threshold, the adaptive update of the control slip rate reference value is started;

[0042] Based on the difference between the cumulative slip ratio error index and the preset error threshold, and combined with the control slip ratio reference value at the previous moment, the updated control slip ratio reference value is calculated.

[0043] The present invention is further configured to dynamically adjust the target braking force based on the updated control slip ratio reference value.

[0044] This invention also provides a real-time adaptive control system for ABS based on wheel hub sensor signal fusion, the system comprising:

[0045] Data acquisition module: used to synchronously acquire multi-source hub sensor signals of each wheel, including wheel speed signal, radial acceleration signal, tangential acceleration signal and braking torque signal;

[0046] Hub response calculation module: used to calculate the hub response coupling factor of the wheel based on the dynamic response characteristics of multi-source hub sensing signals;

[0047] Instantaneous slip ratio calculation module: used to calculate the instantaneous slip ratio of the wheel based on the hub response coupling factor and wheel speed signal, combined with the vehicle's longitudinal speed and tire rolling radius;

[0048] Normal load calculation module: used to calculate the normal load of the wheel based on wheel speed signal, braking torque signal and tangential acceleration signal, combined with hub response coupling factor and instantaneous slip ratio;

[0049] Adhesion coefficient calculation module: used to calculate the adhesion coefficient of the wheel based on the instantaneous slip ratio, normal load and wheel speed signal;

[0050] Adhesion calculation module: It is used to calculate the adhesion capability of the whole vehicle by generating fusion weights based on the deviation between the instantaneous slip rate of each wheel and the preset target slip rate, combined with the wheel hub response coupling factor.

[0051] Target braking force calculation module: used to calculate the target braking force based on the adhesion coefficient, normal load, instantaneous slip ratio and overall vehicle adhesion of each wheel, and adjust the braking intensity of each wheel according to the target braking force.

[0052] This invention provides a real-time adaptive control method and system for ABS based on wheel hub sensor signal fusion. The method comprises: S1: synchronously acquiring multi-source wheel hub sensor signals from each wheel, including wheel speed, radial acceleration, tangential acceleration, and braking torque signals; S2: calculating the wheel hub response coupling factor based on the multi-source wheel hub sensor signals; S3: calculating the instantaneous slip ratio of the wheel based on the wheel hub response coupling factor and wheel speed signals, combined with the vehicle's longitudinal speed and tire rolling radius; S4: based on the wheel speed signals and braking torque signals... S5: Calculate the wheel's normal load using the tangential acceleration signal, combined with the hub response coupling factor and instantaneous slip ratio; S6: Calculate the wheel's adhesion coefficient based on the instantaneous slip ratio, normal load, and wheel speed signal; S7: Calculate the overall vehicle adhesion capability based on the deviation between the instantaneous slip ratio of each wheel and the preset target slip ratio, combined with the hub response coupling factor; S8: Calculate the target braking force based on the adhesion coefficient, normal load, instantaneous slip ratio, and overall vehicle adhesion capability of each wheel, and adjust the braking intensity of each wheel according to the target braking force. The beneficial effects include:

[0053] 1. Real-time wheel status monitoring and control: Through the synchronous acquisition of multi-source wheel hub sensor signals, the wheel speed, acceleration, braking torque and other physical signals are monitored in real time, which can comprehensively reflect the dynamic state of the wheel and ensure that the ABS system has real-time control over the tire adhesion state; through the precise calculation of the wheel hub response coupling factor, the control system can evaluate the working state of the wheel in a timely and accurate manner.

[0054] 2. Improve slip ratio control accuracy: Based on the difference between the instantaneous slip ratio of the wheel and the historical instantaneous slip ratio, combined with the dynamic correction of the wheel hub response coupling factor, the slip ratio of each wheel can be accurately calculated, thereby realizing real-time adjustment of the ABS system; when there is a large deviation between the slip ratio and the preset target slip ratio, the slip ratio reference value is adaptively adjusted, which effectively improves the vehicle braking performance and enhances the vehicle's stability and safety.

[0055] 3. Optimize braking force distribution: By calculating multiple parameters such as the wheel's adhesion coefficient, normal load, instantaneous slip ratio, and overall vehicle adhesion, the braking force distribution can be optimized in real time to ensure a reasonable distribution of braking force between different wheels, effectively preventing excessive or insufficient braking force, thereby optimizing the vehicle's braking response and stability.

[0056] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0057] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0058] Figure 1 A flowchart illustrating an exemplary embodiment of the present invention of a real-time adaptive control method for ABS based on hub sensor signal fusion;

[0059] Figure 2 This is a schematic diagram illustrating the structure of an ABS real-time adaptive control system based on hub sensor signal fusion, as an exemplary embodiment of the present invention. Detailed Implementation

[0060] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0061] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0062] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0063] Example 1

[0064] A real-time adaptive control method for ABS based on hub sensor signal fusion, such as Figure 1 As shown, it includes:

[0065] S1: Synchronously acquire multi-source hub sensing signals of each wheel, including wheel speed signal, radial acceleration signal, tangential acceleration signal and braking torque signal;

[0066] S2: Calculate the wheel hub response coupling factor based on multi-source wheel hub sensing signals;

[0067] S3: Based on the hub response coupling factor and wheel speed signal, combined with the vehicle longitudinal speed and tire rolling radius, calculate the instantaneous slip rate of the wheel;

[0068] S4: Based on wheel speed signal, braking torque signal and tangential acceleration signal, combined with hub response coupling factor and instantaneous slip ratio, calculate the normal load of the wheel;

[0069] S5: Calculate the adhesion coefficient of the wheel based on the instantaneous slip ratio, normal load, and wheel speed signal;

[0070] S6: Based on the deviation between the instantaneous slip rate of each wheel and the preset target slip rate, and combined with the wheel hub response coupling factor, a fusion weight is generated to calculate the overall vehicle adhesion capability.

[0071] S7: Calculate the target braking force based on the adhesion coefficient, normal load, instantaneous slip ratio, and overall vehicle adhesion of each wheel, and adjust the braking intensity of each wheel accordingly.

[0072] The present invention is further configured such that S2 includes:

[0073] The sensors synchronously collect wheel speed signals, radial acceleration signals, tangential acceleration signals, and braking torque signals at the hub position of each wheel.

[0074] Based on the time-series differential operation of the wheel speed signal, the acceleration characteristics of the dynamic changes in wheel speed are extracted;

[0075] The radial vibration intensity characteristics of the wheel hub are calculated based on the differential cumulative amount of the radial acceleration signal.

[0076] Based on the absolute value of the product of the tangential acceleration signal and the braking torque signal, the torque-acceleration coupling characteristics are generated;

[0077] By combining acceleration characteristics, vibration intensity characteristics, and coupling characteristics, the hub response coupling factor is calculated. Specifically, multiple hub sensors simultaneously acquire various signals from the wheel, including wheel speed signals. Radial acceleration signal Tangential acceleration signal and braking torque signal Among them, the position of the wheels Signals corresponding to the four wheels At the current moment, under the constraint of limited space in the passenger car wheel hub, wheel speed, radial acceleration, tangential acceleration, and braking torque signals are selected as core sensing parameters. This combination of sensing parameters, given the current level of sensor integration technology, enables efficient observation of key states such as vertical load on tire contact patch, braking torque transmission characteristics, and adhesion. Using time-series differential calculations of the wheel speed signal, the acceleration characteristics of the dynamic changes in wheel speed are extracted, reflecting the rate of acceleration and deceleration of the wheel during driving. Based on the differential accumulation of the radial acceleration signal, the radial vibration intensity of the wheel hub is calculated, reflecting the radial vibration intensity experienced by the wheel during driving. By calculating the absolute value of the product of the tangential acceleration signal and the braking torque signal, the coupling characteristics of torque and acceleration are generated, reflecting the coupling relationship between acceleration and braking effect. Based on the above acceleration characteristics, vibration intensity characteristics, and coupling characteristics, the wheel hub response coupling factor is calculated. By comprehensively weighting and coupling multiple dynamic signals, an accurate assessment of the wheel dynamic state is provided to the system. The calculation logic of the wheel hub response coupling factor is as follows: , For the first The wheels at all times Hub response coupling factor; For the first The wheels at all times The second-order difference of the wheel speed time series is used to reflect the change in wheel acceleration. The calculation logic is as follows: , , and The first The wheels at all times , and Wheel speed signal; For the first The wheels at all times The differential cumulative amount of the radial acceleration signal is used to measure the intensity of the vibration excitation of the wheel during driving. The calculation logic is as follows: , For difference index, in the formula The range is from 0 to 2, which indicates that the radial acceleration signal data of the past three moments are differentially calculated. By comparing the signals of different time steps, the dynamic change trend of wheel acceleration can be effectively captured, thereby reflecting the acceleration or deceleration of the wheel at different time points. and The first The wheels at all times and radial acceleration signal, This is used to standardize the change in radial acceleration, avoid scalability issues caused by time step or different tire characteristics, and ensure the consistency of calculation results. For the first The wheels at all times The absolute value of the product of the tangential acceleration signal and the braking torque signal is used to reflect the relationship between the torque and tangential acceleration of the wheel during braking. The calculation logic is as follows: , For the first The wheels at all times The tangential acceleration signal, For the first The wheels at all times The braking torque signal; This is a constant used to prevent the denominator from being zero, and its value range is [0.000001, 0.001]. This is an adjustment coefficient used to control the rate of change of the hub response coupling factor, with a value range of [0.1, 5]. The adjustment coefficient is used to measure the strength of the hub response coupling factor, with a value range of [0.1, 5]. By synchronously acquiring multi-source sensor signals and combining the signal characteristics for calculation, it not only captures the dynamic changes of wheel speed, acceleration, and braking torque, but also considers the coupling relationship between wheel vibration and braking torque, thus comprehensively reflecting the real-time dynamic state of the wheel.

[0078] The present invention is further configured such that S3 includes:

[0079] The wheel speed signal is dynamically corrected using the hub response coupling factor;

[0080] The corrected wheel speed signal is mapped to the vehicle's longitudinal speed and tire rolling radius using a nonlinear function to calculate the instantaneous slip ratio of each wheel. Specifically, the collected wheel speed signal is dynamically corrected using the wheel hub response coupling factor. Used to correct the original wheel speed signal This allows the wheel speed signal to better reflect the wheel's response under actual working conditions; the calculation logic for the instantaneous slip ratio is as follows: , For the first The wheels at all times The instantaneous slip ratio is used to measure the difference between the wheel rotation speed and the actual vehicle speed. For vehicles at any time The longitudinal speed of a vehicle represents the overall speed of the vehicle's movement along the forward direction. For the first The rolling radius of a wheel is used to convert the wheel's angular velocity into linear velocity, making it easier to compare with the vehicle's longitudinal velocity. This is an adjustment coefficient used to adjust the weight of the vehicle's longitudinal speed in the instantaneous slip ratio calculation, controlling the sensitivity to changes in vehicle speed. Its value range is [0.8, 1.5]. This is an adjustment coefficient used to adjust the influence of the wheel rolling radius and wheel speed correction term on the denominator, with a value range of [0.2, 0.8]. This is a constant used to prevent abnormal instantaneous slip ratio calculations caused by excessively small denominators; its value range is [0.05, 0.3]. , and The specific value can be determined through real-vehicle calibration or simulation optimization based on vehicle dynamics characteristics and ABS control requirements, in order to improve dynamic response accuracy while ensuring the stability of slip ratio calculation; numerator part The value that measures the difference between the vehicle speed and the corrected circumferential speed of the wheel, i.e., the speed difference between the wheel and the ground; the denominator is... This is used to provide a normalized benchmark, avoiding nonlinear distortion caused by directly using vehicle speed, and also includes a correction term. and constant compensation By dynamically correcting the original wheel speed signal, the interference of external factors on the wheel slip ratio calculation can be effectively eliminated, such as road surface changes and vehicle speed fluctuations, ensuring more accurate instantaneous slip ratio calculation.

[0081] The present invention is further configured such that S4 includes:

[0082] The absolute values ​​of the braking torque signal, the tangential acceleration signal, and the absolute value of the wheel speed signal corrected by the hub response coupling factor are weighted and superimposed to generate a composite basic load term.

[0083] The time-varying compression index is calculated by combining the differential values ​​of wheel speed signal, braking torque signal, and instantaneous slip ratio.

[0084] Based on the composite basic load term and the time-varying compression index, the normal load on the wheel is calculated. Specifically, the absolute values ​​of the braking torque signal and tangential acceleration signal at the current moment, as well as the absolute value of the wheel speed signal after correction by the hub response coupling factor, are weighted and superimposed to obtain the composite basic load term. This composite basic load term can comprehensively reflect the comprehensive external force intensity experienced by the wheel at the current moment. The calculation logic of the composite basic load term is as follows: , For composite foundation load items; This represents the absolute value of the tangential acceleration signal. The absolute value of the wheel speed signal after correction by the hub response coupling factor; This is a constant used to ensure the stability of the denominator and prevent abnormal fluctuations in wheel speed or other signals from causing distortion in the estimation of normal load. Its value range is [0.05, 0.5]. , , and This is the adjustment coefficient; Used to control the nonlinear response intensity of tangential acceleration to the composite foundation load term, with a value range of [0.8, 2]; The weight used to control the influence of the tangential acceleration signal on the composite foundation load term has a value range of [0.1, 2]. Used to adjust the contribution of the wheel speed signal, after correction by the hub response coupling factor, to the composite foundation load term, with a value range of [0.1, 2]. The wheel speed signal, after being corrected by the hub response coupling factor, is used to control the degree of nonlinear enhancement of the composite foundation load term. Its value range is [0.5, 2.5]. The wheel speed, braking torque, and instantaneous slip ratio at the current moment and the previous moment are differentially calculated to obtain the rate of change. The calculation logic for the differential value of the wheel speed signal is as follows: , For the first The wheels at all times The rate of change of wheel speed reflects the magnitude of the change in wheel speed; and The first The wheels at all times and The wheel speed; the calculation logic for the differential value of the braking torque signal is as follows: , For the first The wheels at all times The rate of change of braking torque reflects the influence of the change in braking torque on the adhesion state; and The first The wheels at all times and The braking torque; the calculation logic for the instantaneous slip ratio difference is as follows: , For the first The wheels at all times The instantaneous slip rate change reflects the dynamic fluctuation of the relative slip between the wheel and the road surface; the calculation logic of the time-varying compression index is as follows: , For the first The wheels at all times The time-varying compression index is used to characterize the degree of compression of the current road surface adhesion in a short period of time, making the calculation of normal load more sensitive to sudden changes; The adjustment coefficient is used to control the weight of the wheel speed change rate in the time-varying compression index, and its value ranges from [0.8, 2]. The adjustment coefficient is used to control the weight of the braking torque change rate in the time-varying compression exponent, and its value ranges from [0.8, 2]. This is an adjustment coefficient used to adjust... The result undergoes a nonlinear transformation, with values ​​ranging from [0.5, 1.5]. As an adjustment factor, it controls the degree to which the instantaneous slip rate of change weakens the time-varying compression index, with a value range of [0.05, 2]. Combining the composite basic load term and the time-varying compression index, the normal load is calculated. The normal load represents the force perpendicular to the contact between the wheel and the ground, determining the magnitude of the friction between the tire and the ground, thus affecting the vehicle's braking, acceleration, and cornering performance. The calculation logic for the normal load is as follows: , For the first The wheels at all times The normal load is calculated to provide a high-quality prior for subsequent adhesion coefficient evaluation and braking force distribution. This can synergistically shorten braking distance, reduce the risk of wheel lock-up, and improve vehicle directional stability and braking smoothness under various road conditions.

[0085] The present invention is further configured such that S5 includes:

[0086] Based on the difference between the current instantaneous slip rate and the historical instantaneous slip rate, a difference measurement function is constructed to generate an attachment mapping factor;

[0087] Calculate the absolute difference between the normal load on the wheel at the current moment and the previous moment to obtain the load variation compensation factor;

[0088] Based on wheel speed signals, instantaneous slip ratio, and normal load, combined with the adhesion mapping factor and load variation compensation factor, the wheel's adhesion coefficient is calculated. Specifically, the adhesion mapping factor is calculated by the difference between the current instantaneous slip ratio and the historical instantaneous slip ratio. A difference metric function is used to capture the dynamic characteristics of slip ratio changes over time. This method can effectively reflect the changing trend of the wheel-ground contact force, especially when the slip ratio changes significantly. It can adjust the adhesion mapping factor in real time to optimize wheel adhesion control. The calculation logic of the difference metric function is as follows: , For the first The wheels at all times The adhesion mapping factor, by introducing historical instantaneous slip rate differences, can more accurately capture the dynamic changes between the wheel and the road surface, thus improving the stability of adhesion control. is the attenuation factor, used to adjust the degree of influence of slip ratio difference on the current attachment mapping factor, and its value ranges from [0,1]. The size of the time window for the historical instantaneous slip rate indicates how many historical moments of slip rate variation are considered. For the first The wheels at all times The instantaneous slip ratio represents the degree of slippage between the wheel and the ground at any given moment in the past. The sensitivity parameter is used to adjust the speed at which the slip ratio difference responds to the adjustment of the adhesion mapping factor, and its value ranges from [0.1, 2]. The load variation compensation factor is obtained by calculating the absolute difference between the normal load of the wheel at the current moment and the previous moment. This load variation compensation factor is used to compensate for the influence of wheel load changes on adhesion, ensuring that the adhesion coefficient calculation is more accurate when the wheel load changes drastically. The calculation logic of the load variation compensation factor is as follows: , It is a load variation compensation factor used to dynamically adjust the adhesion coefficient of the wheel to adapt to the fluctuation of the normal load between different time steps, thereby ensuring that the wheel adhesion force keeps in sync with the actual load change and preventing the braking system from becoming unstable or over-responding due to instantaneous load fluctuations. For the first The wheels at all times Normal load; This is an adjustment coefficient used to adjust the degree of compensation for the effect of changes in normal load on the adhesion coefficient, and its value ranges from [0.1, 1]. The scaling factor controls the impact of normal load variations on the adhesion coefficient compensation, with a value range of [0.1, 1]. The adhesion coefficient is a key parameter describing the friction between the wheel and the ground, determining the magnitude of the friction between the tire and the ground. It is calculated by combining slip ratio, wheel speed signal, normal load, adhesion mapping factor, and load variation compensation factor to ensure that the adhesion coefficient accurately reflects the actual adhesion between the wheel and the ground under different working conditions. The calculation logic of the adhesion coefficient is as follows: , For the first The wheels at all times The adhesion coefficient; For vehicles at any time longitudinal vehicle speed; The coefficient is used to adjust the effect of instantaneous slip ratio on the adhesion coefficient, and its value range is [0,1]. The introduction of the adhesion coefficient effectively reduces the adhesion calculation error caused by the change of normal load, ensuring that the vehicle can maintain a stable adhesion coefficient under different working conditions.

[0089] The present invention is further configured such that S6 includes:

[0090] Based on the absolute value of the deviation between the instantaneous slip ratio of each wheel and the preset target slip ratio, the slip profile progress is generated through the exponential decay characteristic;

[0091] Multiply the slip-fit ​​progress and the hub response coupling factor to generate the fusion weights for each wheel;

[0092] Using the adhesion coefficient of each wheel as the base value, and combining it with the corresponding fusion weights, the overall vehicle adhesion capability is calculated. Specifically, the calculation of the slip-applying progress is based on the absolute value of the deviation between the instantaneous slip rate of the wheel and the preset target slip rate, and the decreasing trend of the deviation is used to adjust the slip-applying progress to ensure that the impact of slip rate error on adhesion capability gradually decreases. The fusion weight is calculated by multiplying the slip-applying progress by the hub response coupling factor to generate a weighted weight for each wheel, thereby dynamically adjusting the influence of each wheel and ensuring accurate calculation of wheel adhesion capability. The calculation logic of the fusion weight is as follows: , For the first The wheels at all times The fusion weights; To improve the slip ratio, the difference between the instantaneous slip ratio and the preset target slip ratio is calculated by using the exponential decay of the slip ratio, ensuring that more attention can be paid to wheels whose instantaneous slip ratio is close to the target slip ratio; This is the attenuation factor, used to control the influence of slip ratio deviation on the fusion weight, with a value range of [0.1, 5]. The overall vehicle adhesion capability is determined by the adhesion coefficient of each wheel. and the corresponding fusion weights The weighted average yields the following calculation logic for the overall vehicle adhesion capability: , For vehicles at any time The overall vehicle adhesion capability represents the combined adhesion capability of all wheels of the vehicle, reflecting the sum of the traction force (i.e., adhesion force) generated by all wheels on the road surface under the current environment and conditions. This is a parameter used to prevent the denominator from being zero, and its value range is [0.000001, 0.001]. The weighted sum of the adhesion coefficients of each wheel represents the contribution of the adhesion capability of each wheel to the overall adhesion capability of the wheel. It is a weighted sum of the influence weights of each wheel; by integrating the adhesion coefficients of each wheel, and comprehensively considering the influence of slip ratio proximity and wheel hub response, the adhesion capability of the entire vehicle can be effectively evaluated.

[0093] The present invention is further configured such that S7 includes

[0094] Based on the difference between the overall vehicle adhesion capability and the preset benchmark adhesion capability, and combined with the preset target slip ratio, a reference value for the control slip ratio is calculated.

[0095] Based on the absolute value of the deviation between the control slip ratio reference value and the instantaneous slip ratio, a slip error influence term with attenuation characteristics is constructed;

[0096] Based on the difference between the maximum allowable braking force and the braking force at the previous moment, a braking force mutation suppression term for S-shaped saturation characteristics is constructed.

[0097] The target braking force is obtained by nonlinearly combining the wheel adhesion coefficient, normal load, slip error influence term, and braking force abrupt change suppression term; specifically, the control slip ratio reference value is determined by the overall vehicle adhesion capacity. The difference between the adhesion capability and the preset benchmark, and the preset target slip ratio. The combined generation and calculation logic of the control slip ratio reference value are as follows: , For vehicles at any time The control slip ratio reference value; Preset baseline adhesion capability; and This is the adjustment coefficient; Used to adjust the relationship between the overall vehicle adhesion and the preset target slip ratio, with a value range of [0.1, 1]; The response rate used to adjust the difference between the adhesion capability and the preset target slip ratio has a value range of [0.1, 1]. The formula for calculating the control slip ratio reference value uses the difference between the overall vehicle adhesion capability and the preset target adhesion capability, combined with the preset target slip ratio, to generate the control slip ratio reference value through nonlinear mapping, ensuring that the system can dynamically adjust to a control slip ratio that matches the current road conditions and adhesion capability. The calculation of the target braking force is based on a nonlinear combination of the wheel adhesion coefficient, normal load, slip error influence term, and braking force mutation suppression term. The braking force distribution considers the nonlinear decay of the slip ratio error and introduces a Sigmoid-type suppression factor to prevent braking force mutation, thereby improving the stability and ride comfort of the system. The calculation logic of the target braking force is as follows: , For the first The wheels at all times The target braking force is used to adjust the wheel braking effect of the system. is the attenuation factor, used to adjust the degree of influence of slip ratio deviation on target braking force, and its value ranges from [0,1]. This is a nonlinear response factor used to adjust the nonlinear effect of slip ratio deviation on target braking force, and its value range is [0,1]. The inhibition factor is used to avoid drastic fluctuations in braking force over time, and its value ranges from [0,5]. For the first The maximum permissible braking force of the wheel; For the first The wheels at all times The target braking force; This is the slip error factor, which affects the distribution of the target braking force. The greater the difference between the slip ratio reference value and the instantaneous slip ratio, the smaller the slip error factor, thus reducing its contribution to the target braking force. This is a braking force mutation suppression term, used to prevent sudden changes in braking force caused by instantaneous changes in slip ratio or other factors. Through the smoothing characteristics of the Sigmoid function, the braking force transitions smoothly between different time points, effectively avoiding excessive or unstable braking responses. Through the above calculations, the system achieves precise control of wheel braking force, optimizes the balance between slip ratio and braking force, and enables the ABS system to dynamically adjust the target braking force distribution according to different road conditions and changes in adhesion, and adjust the braking intensity of each wheel according to the target braking force.

[0098] The present invention is further configured to calculate the cumulative slip rate error index based on the deviation between the control slip rate reference value and the instantaneous slip rate of each wheel, combined with the adhesion coefficient of each wheel and the hub response coupling factor;

[0099] When the cumulative slip ratio error exceeds the preset error threshold, the adaptive update of the slip ratio reference value is initiated.

[0100] Based on the difference between the cumulative slip ratio error index and the preset error threshold, and combined with the control slip ratio reference value from the previous moment, the updated control slip ratio reference value is calculated. Specifically, the cumulative slip ratio error index measures the overall error of the system during the control slip ratio process. It comprehensively considers the deviation between the control slip ratio reference value and the instantaneous slip ratio of each wheel, and combines the wheel's adhesion coefficient and the hub response coupling factor. The calculation logic of the cumulative slip ratio error index is as follows: , It is a cumulative slip ratio error index used to measure the overall error in slip ratio deviation, avoiding adjustments based solely on slip ratio error at a single moment; Indicates from time At the time That is, a preset time window At all times within, For a specific moment; For vehicles at any time The control slip ratio reference value; No. The wheels at all times The instantaneous slip rate; For the first The wheels at all times The adhesion coefficient; For the first The wheels at all times Hub response coupling factor; is the exponential coefficient used to control the influence of slip ratio deviation on the cumulative slip ratio error index, and its value ranges from [0.5, 5]. The adjustment coefficient is used to control the influence of the adhesion coefficient and the hub response coupling factor during the error accumulation process, and its value range is [0.1, 1]. In the above calculation logic for the cumulative slip ratio error index, the outer summation represents the accumulation of the error at each moment within a time window, while the inner summation represents the summation of the error for each wheel, ensuring that the slip ratio error of the entire vehicle is comprehensively considered. When the cumulative slip ratio error index... When the error exceeds the preset error threshold, it indicates a decrease in the control accuracy of the ABS system, requiring adjustment of the control slip ratio. This necessitates initiating an adaptive update mechanism for the control slip ratio reference value, updating the reference value accordingly. To achieve precise adjustment and improve control performance, the update logic for the control slip ratio reference value is as follows: , For vehicles at any time The updated control slip ratio reference value; For the vehicle at the previous moment The control slip ratio reference value; and This is the adjustment coefficient; The preset error threshold is used; Used to control the magnitude of each adjustment of the control slip ratio reference value, with a value range of [0.01, 1]; Used to adjust the system's response sensitivity to slip ratio error, with a value range of [0,5]. The adaptive adjustment can respond to changes in slip ratio error in real time, ensuring that the system can operate quickly and stably under various working conditions.

[0101] The invention is further configured to dynamically adjust the target braking force based on the updated control slip ratio reference value. Specifically, when the control slip ratio reference value is updated, the new control slip ratio reference value directly affects the calculation of the target braking force. The updated control slip ratio reference value serves as input, and by adjusting the target braking force, the system ensures that while maintaining vehicle stability, it optimizes the distribution of braking force, thereby achieving a more precise and efficient braking effect. This dynamic adjustment mechanism can respond in real time to various driving conditions, especially when the slip ratio changes significantly. By adjusting the control slip ratio reference value, it reduces slip ratio errors and avoids excessive deviations, thereby improving braking performance and enhancing system safety. In addition, the system can intelligently adapt to different road conditions, vehicle speed changes, and other dynamic factors, ensuring that the wheels always remain within a range close to the optimal slip ratio, thus providing a more stable and safer driving experience.

[0102] In this invention, the system optimizes vehicle braking performance by dynamically adjusting the target braking force through the acquisition of multi-source sensor data from the wheels and combining it with a control algorithm. The system simultaneously acquires multi-source hub sensor signals from each wheel, with each wheel's data including wheel speed, radial acceleration, tangential acceleration, and braking torque signals. The system optimizes braking performance by calculating the overall vehicle adhesion and target braking force at each time point k in real time. For example, at time k=1, the system acquires a wheel speed signal of 15.3 m / s, a radial acceleration signal of 2.6 m / s², and a tangential acceleration signal of 2.0 m / s² for the first wheel. The driving torque is 260 Nm; the wheel speed signal of the second wheel is 15.0 m / s, the radial acceleration signal is 2.7 m / s², the tangential acceleration signal is 1.9 m / s², and the braking torque is 255 Nm. At this time, the overall vehicle adhesion is 0.87. The system calculates the target braking force of the first wheel to be 125 N and the target braking force of the second wheel to be 123 N. At time k=2, the system collects the wheel speed signal of the first wheel as 15.2 m / s, the radial acceleration signal as 2.3 m / s², the tangential acceleration signal as 1.8 m / s², and the braking torque as 250 Nm; the wheel speed signal of the second wheel is 14.8 m / s². At this time, the radial acceleration signal is 2.5 m / s², the tangential acceleration signal is 1.7 m / s², and the braking torque is 245 Nm. The overall vehicle adhesion is 0.85. The target braking force for the first wheel is adjusted to 120 N, and the target braking force for the second wheel is 118 N. Based on real-time wheel status data and the calculated overall vehicle adhesion and target braking force, the system can dynamically adjust the braking force output to ensure optimal braking performance under different road conditions. When the overall vehicle adhesion is high, such as at time k=1, the system sets the target braking forces for the first and second wheels to 125 N and 123 N respectively. When the vehicle's traction is low, such as at time k=2, the system reduces the target braking force of the first and second wheels to 120N and 118N respectively, thereby preventing wheel slippage or loss of control. Through this dynamic adjustment mechanism, the vehicle can optimize braking performance according to different braking needs, monitor and control the sensor data of each wheel in real time, and make the braking force precisely adjustable, thus maintaining optimal traction and braking performance under various road conditions. This control system not only improves the vehicle's safety and stability, but also prevents wheel lock-up or excessively low traction, especially under wet or complex road conditions, ensuring efficient and accurate braking response.

[0103] Example 2

[0104] Please see Figure 2 This exemplary real-time adaptive ABS control system based on hub sensor signal fusion includes:

[0105] Data acquisition module: used to synchronously acquire multi-source hub sensor signals of each wheel, including wheel speed signal, radial acceleration signal, tangential acceleration signal and braking torque signal;

[0106] Hub response calculation module: used to calculate the hub response coupling factor of the wheel based on the dynamic response characteristics of multi-source hub sensing signals;

[0107] Instantaneous slip ratio calculation module: used to calculate the instantaneous slip ratio of the wheel based on the hub response coupling factor and wheel speed signal, combined with the vehicle's longitudinal speed and tire rolling radius;

[0108] Normal load calculation module: used to calculate the normal load of the wheel based on wheel speed signal, braking torque signal and tangential acceleration signal, combined with hub response coupling factor and instantaneous slip ratio;

[0109] Adhesion coefficient calculation module: used to calculate the adhesion coefficient of the wheel based on the instantaneous slip ratio, normal load and wheel speed signal;

[0110] Adhesion calculation module: It is used to calculate the adhesion capability of the whole vehicle by generating fusion weights based on the deviation between the instantaneous slip rate of each wheel and the preset target slip rate, combined with the wheel hub response coupling factor.

[0111] Target braking force calculation module: used to calculate the target braking force based on the adhesion coefficient, normal load, instantaneous slip ratio and overall vehicle adhesion of each wheel, and adjust the braking intensity of each wheel according to the target braking force.

[0112] It should be noted that the ABS real-time adaptive control system based on wheel hub sensor signal fusion provided in the above embodiments and the ABS real-time adaptive control method based on wheel hub sensor signal fusion provided in the above embodiments belong to the same concept. The specific operation methods of each module and unit have been described in detail in the method embodiments and will not be repeated here. In practical applications, the ABS real-time adaptive control system based on wheel hub sensor signal fusion provided in the above embodiments can be assigned to different functional modules as needed, that is, the internal structure of the system can be divided into different functional modules to complete all or part of the functions described above. This is not a limitation here.

[0113] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for ABS real-time adaptive control based on wheel hub sensing signal fusion, characterized in that, The method comprises the following steps: S1: synchronously collecting multi-source wheel hub sensing signals of each wheel, wherein the multi-source wheel hub sensing signals comprise wheel speed signals, radial acceleration signals, tangential acceleration signals and braking torque signals; S2: calculating wheel hub response coupling factors of the wheels based on the multi-source wheel hub sensing signals, comprising: synchronously collecting wheel speed signals, radial acceleration signals, tangential acceleration signals and braking torque signals of each wheel hub position through sensors; extracting acceleration characteristics of dynamic changes in wheel speed through time sequence difference operation of the wheel speed signals; calculating radial vibration intensity characteristics of the wheel hub based on difference accumulation of the radial acceleration signals; generating force torque and acceleration coupling characteristics according to the product absolute value of the tangential acceleration signals and the braking torque signals; and comprehensively calculating the wheel hub response coupling factors based on the acceleration characteristics, the vibration intensity characteristics and the coupling characteristics; S3: calculating instantaneous slip rates of the wheels based on the wheel hub response coupling factors and the wheel speed signals, in combination with a vehicle longitudinal speed and a tire rolling radius; S4: calculating normal loads of the wheels based on the wheel speed signals, the braking torque signals and the tangential acceleration signals, in combination with the wheel hub response coupling factors and the instantaneous slip rates, comprising: weighting and superimposing absolute values of the braking torque signals, the tangential acceleration signals and the wheel speed signals corrected by the wheel hub response coupling factors to generate a composite basic load term; calculating a time-varying compression index in combination with difference values of the wheel speed signals, the braking torque signals and the instantaneous slip rates; and calculating the normal loads of the wheels based on the composite basic load term and the time-varying compression index; S5: calculating adhesion coefficients of the wheels according to the instantaneous slip rates, the normal loads and the wheel speed signals; S6: generating fusion weights in combination with the wheel hub response coupling factors according to deviations of the instantaneous slip rates of the wheels from a preset target slip rate, and calculating a whole-vehicle adhesion capacity; S7: calculating target braking forces according to the adhesion coefficients of the wheels, the normal loads, the instantaneous slip rates and the whole-vehicle adhesion capacity, and adjusting braking intensities of the wheels according to the target braking forces. 2.The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 1, wherein, The S3 comprises: dynamically correcting the collected wheel speed signals by using the wheel hub response coupling factors; mapping the corrected wheel speed signals, the vehicle longitudinal speed and the tire rolling radius through a nonlinear function to calculate the instantaneous slip rates of each wheel. 3.The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 1, characterized in that, The S5 comprises: constructing a difference measurement function based on differences between the current instantaneous slip rates and historical instantaneous slip rates to generate an adhesion mapping factor; calculating absolute difference values between the normal loads of the wheels at a current time and a previous time to obtain load variation compensation factors; calculating the adhesion coefficients of the wheels based on the wheel speed signals, the instantaneous slip rates and the normal loads of the wheels, in combination with the adhesion mapping factor and the load variation compensation factor.

4. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 1, characterized in that, The S6 comprises: generating a slip inlay degree through an exponential decay characteristic based on absolute values of deviations of the instantaneous slip rates of the wheels from the preset target slip rate; multiplying the slip inlay degree and the wheel hub response coupling factor to generate fusion weights of the wheels; calculating the whole-vehicle adhesion capacity by weighting the adhesion coefficients of the wheels as base values in combination with the corresponding fusion weights.

5. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 1, characterized in that, The S7 comprises The control slip ratio reference value is calculated based on a difference between the total vehicle adhesion capacity and a preset reference adhesion capacity, and in combination with a preset target slip ratio; A slip error influence term with a damping characteristic is constructed according to an absolute value of a deviation between the control slip ratio reference value and the instantaneous slip ratio; A brake force mutation inhibition term with an S-shaped saturation characteristic is constructed based on a difference between the maximum allowable brake force and the brake force at the previous moment; The wheel adhesion coefficient, the normal load, the slip error influence term and the brake force mutation inhibition term are nonlinearly combined to obtain the target brake force.

6. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 5, characterized in that, A slip ratio error accumulation index is calculated based on a deviation between the control slip ratio reference value and the instantaneous slip ratio of each wheel, in combination with the adhesion coefficient of each wheel and the hub response coupling factor; When the slip ratio error accumulation index is greater than a preset error threshold, the adaptive update of the control slip ratio reference value is started; The updated control slip ratio reference value is calculated based on a difference between the slip ratio error accumulation index and the preset error threshold, in combination with the control slip ratio reference value at the previous moment.

7. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 6, characterized in that, The target brake force is dynamically adjusted according to the updated control slip ratio reference value.

8. The ABS real-time adaptive control system based on wheel-sensor signal fusion, for implementing the ABS real-time adaptive control method based on wheel-sensor signal fusion according to any one of claims 1-7, characterized in that, The method comprises: a data acquisition module for synchronously acquiring multi-source hub sensing signals of each wheel, the multi-source hub sensing signals comprising wheel speed signals, radial acceleration signals, tangential acceleration signals and brake torque signals; a hub response calculation module for calculating a hub response coupling factor of the wheel based on dynamic response characteristics of the multi-source hub sensing signals; an instantaneous slip ratio calculation module for calculating an instantaneous slip ratio of the wheel based on the hub response coupling factor and the wheel speed signals, in combination with a vehicle longitudinal speed and a tire rolling radius; a normal load calculation module for calculating a normal load of the wheel based on the wheel speed signals, the brake torque signals and the tangential acceleration signals, in combination with the hub response coupling factor and the instantaneous slip ratio; an adhesion coefficient calculation module for calculating an adhesion coefficient of the wheel according to the instantaneous slip ratio, the normal load and the wheel speed signals; an adhesion capacity calculation module for calculating a total vehicle adhesion capacity by generating a fusion weight according to a deviation between the instantaneous slip ratio of each wheel and a preset target slip ratio, in combination with the hub response coupling factor; a target brake force calculation module for calculating a target brake force according to the adhesion coefficient, the normal load, the instantaneous slip ratio and the total vehicle adhesion capacity of each wheel, and adjusting the brake intensity of each wheel according to the target brake force.

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