A method for high-frequency swaying identification and torque damping control of dual-drive single-track vehicles

Abstract

This invention discloses a method for high-frequency yaw identification and torque damping control of a dual-drive, single-track vehicle. Yaw angular velocity is collected by first and second inertial measurement nodes located at the front steering assembly and the main frame, respectively. The differential yaw angular velocity of the front steering assembly relative to the main frame is calculated, and the differential yaw angular velocity is filtered by the target yaw frequency band to extract the frequency band energy, yaw envelope amplitude, envelope growth rate, target yaw frequency, and phase stability. The yaw risk state is determined in conjunction with vehicle speed. When a divergent trend in high-frequency yaw is confirmed, the vehicle control unit issues a limited asymmetric longitudinal torque command to the front and rear wheel FOC controllers, executing longitudinal tension, rear wheel steady-speed traction, or phase-locked torque ripple control, and limiting the slope of the braking input. When the yaw envelope decreases or occupant instability and vehicle malfunction are detected, intervention is gradually released or degraded protection is initiated.

Description

Technical Field

[0001] This invention relates to the field of active safety and chassis drive-by-wire technology for micro electric vehicles, and particularly to a high-frequency sway recognition and torque damping control method for dual-drive single-track vehicles. It is applicable to electric scooters, straddle-type micro electric vehicles, off-road scooters and similar single-track or narrow-wheelbase vehicles with front and rear wheels that are approximately collinear and equipped with drive motors for the front and rear wheels respectively. It involves inertial measurement, frequency domain signal processing, vehicle control unit control, FOC motor control and regenerative braking control. Background Technology

[0002] High-speed electric scooters, off-road scooters, and some straddle-type micro-vehicles typically use a front-to-rear longitudinal wheel system, characterized by a short wheelbase, small wheel diameter, lightweight steering components, and a high center of gravity for the rider. When the vehicle passes through road seams, gravel, or local protrusions at high speed, or is subjected to disturbances such as crosswinds, momentary sideslip of the front wheel, or asymmetrical handling by the rider, the front steering component may experience high-frequency left-right oscillations relative to the main frame, gradually forming continuous or divergent oscillations. Normal steering and road bumps are usually manifested as the coordinated movement of the front steering component and the main frame, while high-frequency shimmy is mainly manifested as the alternating swinging of the front steering component relative to the main frame. Existing micro-vehicles mostly collect the overall vehicle attitude through a single inertial measurement unit set on the frame, which makes it difficult to accurately distinguish between overall frame vibration, normal steering and abnormal shimmy of the front steering component. When judging based solely on instantaneous vibration amplitude, it is also easy to be falsely triggered by road impacts, or to intervene only after the shimmy has developed significantly. Existing mechanical or hydraulic steering dampers mainly limit the sway of the steering components by fixing the damping. When the damping is large, it will increase the steering resistance at low speeds, and when the damping is small, the ability to limit high-speed sway is limited. At the same time, it will also increase the weight of the whole vehicle, installation space and maintenance requirements. Automotive electronic stability control systems usually rely on the difference in braking force between the left and right wheels to generate yaw moment. However, the front and rear wheels of single-track or narrow-track vehicles are approximately collinear, making it difficult to directly adopt this type of control method. If the power is cut off or the front wheel is forced to brake directly after sway is detected, it may cause sudden changes in longitudinal driving force and front wheel load, further affecting the stability of the vehicle. In addition, high-frequency shimmy is usually accompanied by energy concentration in a specific frequency band, continuous growth of the shimmy envelope, and relatively stable phase relationship. It is difficult to accurately determine whether it has a divergence trend by using only a single amplitude threshold. During shimmy, sudden braking by the occupants, sudden changes in throttle, occupant instability, or drive system failure can also affect the safety of torque intervention.

[0003] To address this, a method for identifying high-frequency swaying and controlling torque damping in dual-drive single-track vehicles is proposed. Summary of the Invention

[0004] In view of this, the present invention provides a method for high-frequency sway identification and torque damping control of a dual-drive single-track vehicle, so as to solve or alleviate the technical problems existing in the prior art, and at least provide a beneficial option.

[0005] The technical solution of this invention is implemented as follows: A method for high-frequency shimmy identification and torque damping control of a dual-drive single-track vehicle, applied to a single-track or narrow-track micro-vehicle where the front and rear wheels are driven by a front-wheel drive motor and a rear-wheel drive motor respectively, and the front and rear wheels are approximately collinear, executed by the vehicle control unit (VCU), including the following steps: S1. Obtain the target oscillation frequency band calibrated by the vehicle model, and perform time stamp synchronization, zero bias correction, coordinate system alignment and sampling delay compensation on the first inertial measurement node and the second inertial measurement node; S2. Synchronously acquire the yaw rate of the steering component output by the first inertial measurement node. The yaw rate of the main frame output by the second inertial measurement node The vehicle's speed, front wheel speed, and rear wheel speed, according to Calculate the differential yaw rate and the differential yaw rate Preprocessing is required; S3, Processed differential yaw rate The target shimmy frequency band was bandpass filtered according to the vehicle model calibration to obtain the filtered shimmy signal. And according to the oscillation signal Calculate the energy of the frequency band Filtered oscillation envelope amplitude Envelope growth rate Target oscillation frequency and phase stability; S4. Based on the target oscillation frequency Whether it is located within the target oscillation frequency band, and the amplitude of the filtered oscillation envelope. The envelope growth rate The phase stability and the vehicle speed determine the shimmy risk level. And according to the said oscillation risk level The oscillation risk state machine switches between the S0 normal state, S1 warning state, S2 confirmation state, S3 intervention state, S4 release state, and S5 degraded state. S5, when the aforementioned oscillation risk level When the intervention threshold is exceeded and the S3 intervention state is entered, the oscillation risk level is determined accordingly. The oscillation signal Based on the phase, vehicle speed, tire adhesion estimation, and occupant status, the target torque for the front wheels is issued to the front wheel FOC controller and the rear wheel FOC controller. and target torque for rear wheels Control the front-wheel drive motor and the rear-wheel drive motor to execute at least one of the longitudinal tension mode, the rear-wheel steady-speed traction mode or the phase-locked torque ripple mode, superimpose the shimmy intervention term onto the normal drive torque or the normal braking torque, and limit the amplitude, rate of change, duration and net longitudinal acceleration change of the intervention torque. S6, when the filtered oscillation envelope amplitude When the speed drops below the release threshold and remains below the preset cycle, the sway intervention is gradually withdrawn according to the preset slope and normal riding control is restored. When occupant instability, inertial measurement node failure, FOC failure or battery failure is detected, the system enters the S5 degraded state, stops the longitudinal tension mode and phase-locked torque ripple mode, and switches to power-limited coasting, amplitude-limited braking or power-off protection.

[0006] More preferably, during vehicle operation, the vehicle control unit (VCU) synchronously collects the yaw rate of the steering component and the yaw rate of the main frame at a sampling frequency not less than 10 times the upper limit of the target yaw frequency band and not less than 200 Hz; in one specific parameter configuration, the sampling frequency can be set to 500 Hz to 1000 Hz; the preprocessing includes zero bias removal, gravity coupling removal, and outlier removal; the synchronously collected vehicle operation signals also include at least one of the following: estimated vehicle speed, front wheel slip ratio, rear wheel slip ratio, motor back EMF, throttle signal, mechanical braking signal, electronic braking signal, remote control braking signal, emergency stop command, front wheel motor current, rear wheel motor current, and occupant status signal.

[0007] Further preferably, the first inertial measurement node is rigidly connected to the handlebars, steering column, front fork axle, front wheel motor housing, or a structure fixedly connected to the front steering assembly, and is used to collect the yaw rate, lateral acceleration, or steering angle-related dynamic quantities of the front steering assembly; the second inertial measurement node is rigidly connected to the frame main beam, the middle of the pedals, the battery pack housing, or a structural component near the vehicle's center of gravity, and is used to collect the yaw rate, lateral acceleration, and attitude information of the entire frame.

[0008] More preferably, the vehicle control unit (VCU) also calculates correlation coefficients. and the correlation coefficient With the differential yaw rate The energy within the target sway frequency band is used to identify the high-frequency alternating swaying of the front steering assembly relative to the frame main body; when the differential energy within the target sway frequency band increases and the correlation coefficient decreases relative to the coordinated motion state of the front steering assembly and the frame main body, it is used as one of the criteria for determining the high-frequency alternating swaying.

[0009] More preferably, the target yaw frequency band calibrated by the vehicle model is a sub-interval within the range of 4Hz to 14Hz. The target yaw frequency band can be determined based on factory sweep frequency test or road test data. The target yaw frequency band corresponding to different vehicle models is calibrated separately according to their structure and operating characteristics. When the target yaw frequency band is 5Hz to 12Hz, the differential yaw rate is... Frequency domain analysis is performed using IIR bandpass filtering, FIR bandpass filtering, short-time Fourier transform, or sliding Goertzel algorithm. Envelope or phase features are obtained by rectification, Hilbert transform, sliding peak extraction, or phase-locked loop phase tracking.

[0010] More preferably, the filtered oscillation envelope amplitude The envelope growth rate is obtained through rectification, Hilbert transform, or sliding peak extraction. according to Calculate, where, It can be expressed as time, or determined based on the amplitude ratio of adjacent periods.

[0011] Further preferably, the confirmation criteria for high-frequency oscillation include: the target oscillation frequency. Located within the target oscillation frequency band specified by the vehicle model; The filtered oscillation envelope amplitude Greater than the first risk threshold ; The envelope growth rate Greater than the growth threshold or continuous One and a half cycles satisfy The phase drift between adjacent cycles is less than a set threshold. The vehicle's speed exceeds 15 km / h or is higher than the speed threshold specified by the vehicle model; wherein, This indicates the number of half-cycles in a continuous decision. Indicates the first The amplitude of one and a half cycles, Indicates the first The amplitude of one and a half cycles, This indicates the percentage increase in amplitude between adjacent half-cycles.

[0012] More preferably, the oscillation risk state machine is in the S0 normal state when no divergence characteristics are detected within the target oscillation frequency band, and enters the S1 warning state when an energy increase within the target oscillation frequency band is detected. Located within the target oscillation frequency band and the filtered oscillation envelope amplitude When the threshold is exceeded, the S1 warning state is maintained. When the envelope divergence condition is met for a consecutive preset period, the state transitions from the S1 warning state to the S2 confirmation state, which is the oscillation risk level. When the threshold is exceeded, the system transitions from the S2 confirmation state to the S3 intervention state, where the amplitude of the filtered oscillation envelope is... Below the release threshold and remain During each cycle, it transitions from the S3 intervention state to the S4 release state, and enters the S5 degradation state when occupant load loss, FOC failure, battery failure or sensor failure is detected. When the energy in the target oscillation frequency band decreases under the S1 warning state, it returns to the S0 normal state. When the high-frequency oscillation confirmation condition disappears under the S2 confirmation state, it returns to the S1 warning state. When the high-frequency oscillation diverges again under the S4 release state, it returns to the S2 confirmation state or the S3 intervention state. When the high-frequency oscillation remains stable, it returns to the S0 normal state.

[0013] Further preferably, the longitudinal tension mode includes: controlling the front-wheel drive motor to apply a positive micro-traction torque and controlling the rear-wheel drive motor to apply a regenerative anti-drag torque during a preset intervention period, wherein the target torque of the front wheels... and the target torque of the rear wheels They respectively satisfy: ; ; ; In the formula, Indicates the magnitude of the intervention torque. This represents the ratio of the rear wheel regenerative drag torque amplitude to the front wheel positive micro-traction torque amplitude; the vehicle control unit (VCU) controls the intervention torque amplitude. Limit the target torque of the front wheels. and the target torque of the rear wheels The change in net longitudinal acceleration of the vehicle after being output by the corresponding drive motor does not exceed the set safety threshold.

[0014] Further preferably, the rear wheel steady-speed traction mode includes: when no driving torque is applied to the front wheels, controlling the rear wheel drive motor to output a limited traction torque or a limited regenerative anti-drag torque to maintain vehicle speed, and limiting the rise rate of the front wheel electronic braking torque or the front wheel regenerative braking torque controlled by the vehicle control unit (VCU).

[0015] More preferably, the phase-locked torque ripple mode includes: the vehicle control unit (VCU) based on the shimmy signal. Phase estimation is performed to inject an AC torque component that is opposite in phase to the oscillation or has a preset phase difference into the front-wheel drive motor or the rear-wheel drive motor. The AC torque component It is limited by motor current, battery power, tire adhesion and occupant status.

[0016] Further preferably, the longest duration of a single torque intervention is calibrated in the range of 0.1s to 1.0s, the upper limit of the single intervention torque is calibrated in the range of 5% to 30% of the currently available drive torque, the intervention torque is also limited by the maximum rate of change, temperature protection threshold and current protection threshold, and the net longitudinal acceleration change generated during the intervention does not exceed the set safety threshold.

[0017] Further preferably, in the S1 warning state to S3 intervention state, sudden changes in throttle, sudden changes in wireless control, and sudden changes in electronic braking commands or regenerative braking commands controlled by the vehicle control unit (VCU) are processed by limiting the amplitude or slope; when a rider inputs a forced forward braking or emergency braking command, the sway risk level is determined. Limit the rise rate of the front wheel electronic braking torque or the front wheel regenerative braking torque, and redistribute the front and rear wheel electronic braking torque. The limiting or slope limiting process does not apply to the mechanical braking directly applied by the rider. When the occupant's condition is stable and the amplitude of the filtered oscillation envelope is... While the pressure is still rising, the priority of the front wheel electronic braking or regenerative braking controlled by the vehicle control unit (VCU) is reduced for a preset duration. When occupant instability, obstacle collision risk, tire adhesion not meeting intervention conditions, sudden drop in vehicle speed, FOC failure, or battery failure are detected, the reduction of the front wheel electronic braking or regenerative braking priority is stopped, and a safety-priority degraded braking strategy is switched to.

[0018] More preferably, the occupant state is determined by at least two independent signals from the following: pedal pressure sensor, foot pedal area micro-strain array, vehicle grip detection, motor load, sudden change in vehicle posture, or remote control release detection. When at least two independent occupant state signals meet the corresponding instability judgment conditions, the occupant is determined to be instable and the sway risk state machine enters the S5 degraded state. The instability judgment conditions include the occupant's two-foot load decreasing amplitude or decreasing rate exceeding a preset threshold, the pressure center trajectory deviating from a preset stable range, or the rate of change of the vehicle tilt angle exceeding a preset threshold.

[0019] Further preferably, in the S5 degraded state, the longitudinal tension mode and phase-locked torque ripple mode are stopped, and the rear wheel braking or power-off protection with limited power coasting, limited amplitude and limited slope is switched; when the vehicle control unit (VCU) confirms that the fault has been cleared through fault diagnosis, and the occupant is in a stable riding state and the vehicle speed is within a safe range, the preset recovery time is maintained continuously, and after receiving a re-enable command or fault latch release signal, the S5 degraded state is released, and the shimmy risk state machine is restored to the S0 normal state.

[0020] The embodiments of the present invention have the following advantages due to the adoption of the above technical solutions: I. This invention collects yaw rate by setting two inertial measurement nodes at the front steering assembly and the main frame respectively, and performs differential processing on the two, which can distinguish between ordinary bending and overall frame swaying and high-frequency swaying of the front wheel or steering column relative to the main frame, thereby reducing the probability of false triggering in the high-frequency swaying identification process.

[0021] Second, this invention combines the target oscillation frequency band, oscillation envelope amplitude, envelope growth rate and phase stability to judge high-frequency oscillation. It can not only identify the oscillation amplitude, but also determine whether the oscillation has a continuous growth or divergence trend, so as to intervene before the oscillation develops further.

[0022] Third, this invention utilizes the vehicle's existing front-wheel drive motor, rear-wheel drive motor, and corresponding FOC controller to perform asymmetric longitudinal torque intervention on the front and rear wheels, actively suppressing shimmy energy. It eliminates the need for additional mechanical or hydraulic steering dampers, reducing the impact of additional damping structures on vehicle weight, installation space, and low-speed steering.

[0023] Fourth, this invention sets amplitude limits, rate of change limits, and maximum duration limits for intervention torque, and controls the entry, maintenance, and gradual release of intervention through a shimmy risk state machine. This can reduce the longitudinal impact caused by the torque intervention itself and avoid the sudden entry or exit of intervention commands from creating new disturbances to the vehicle's driving state.

[0024] Fifth, this invention links the rider's state with the sway intervention process. When it is detected that the rider has lost a stable riding state, the sensor has failed, or the drive system has malfunctioned, the longitudinal tension or phase-locking torque ripple intervention is stopped, and the system switches to power-limited coasting, gentle braking, or power-off protection to reduce the secondary risks caused by continuing to apply inappropriate torque.

[0025] The above overview is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the invention will become readily apparent from the accompanying drawings and the following detailed description. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the arrangement of the single-track vehicle of the present invention. Detailed Implementation

[0028] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0029] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0030] This invention provides a method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle. This method is applied to a single-track or narrow-track micro vehicle with drive motors configured on the front and rear wheels respectively, and the front and rear wheels being approximately collinear. The vehicle can be a dual-drive electric scooter, a dual-drive straddle-type micro electric vehicle, an off-road scooter, or a drive-by-wire vehicle with a front and rear longitudinal wheel system.

[0031] like Figure 1As shown, the vehicle is equipped with a first inertial measurement node, a second inertial measurement node, a vehicle speed and wheel speed acquisition module, a braking and throttle acquisition module, a vehicle control unit (VCU), a front wheel FOC controller, and a rear wheel FOC controller. The first inertial measurement node is rigidly connected to the front steering assembly and is used to acquire the yaw rate, lateral acceleration, or steering angle-related dynamics of the front steering assembly. The second inertial measurement node is rigidly connected to the frame backbone or pedal load-bearing structure and is used to acquire the yaw rate, lateral acceleration, and attitude information of the entire frame. The vehicle control unit (VCU) receives signals from the two inertial measurement nodes, the vehicle speed and wheel speed acquisition module, and the braking and throttle acquisition module, and issues target torque, slope limit commands, and regenerative braking commands to the front wheel FOC controller and the rear wheel FOC controller. Figure 1 The front steering component IMU corresponds to the first inertial measurement node, and the frame main IMU corresponds to the second inertial measurement node.

[0032] Inertial measurement node setup and target oscillation frequency band acquisition: After the first and second inertial measurement nodes are installed, time stamp synchronization, zero-bias correction, coordinate system alignment, and sampling delay compensation are performed on the two inertial measurement nodes to ensure that their output yaw angular velocities have a unified time and direction reference. The vehicle control unit (VCU) acquires the target yaw frequency band calibrated by the vehicle model. The target yaw frequency band is determined and stored through factory frequency sweep test or road test data.

[0033] After the two inertial measurement units (IMUs) are installed, they undergo timestamp synchronization, zero-bias correction, coordinate system alignment, and sampling delay compensation to ensure that the yaw velocities output by the two IMUs have a unified time and direction reference. During coordinate system alignment, the axes used by the two IMUs to characterize yaw motion are unified to the vertical axis of the vehicle, so that the yaw velocities output by the first IMU for the steering assembly are consistent with these axes. The second inertial measurement node outputs the yaw rate of the main frame. .

[0034] The target shimmy frequency band is calibrated based on the vehicle's wheelbase, wheel diameter, steering component mass, frame stiffness, and drive system parameters. The target shimmy frequency band can be determined through factory frequency sweep tests or road test data and is acquired by the vehicle control unit (VCU) when the vehicle performs high-frequency shimmy identification and torque damping control. The target shimmy frequency band is located in a sub-range of 4 Hz to 14 Hz. For some dual-drive electric scooters, 5 Hz to 12 Hz can be used as the target shimmy frequency band. The target shimmy frequency band is used to extract the high-frequency alternating oscillation of the front steering component relative to the frame backbone from ordinary steering, overall frame sway, and random road impacts. The specific frequency band is determined based on the test results of the corresponding vehicle model and is not a fixed frequency band used as a uniform parameter for all vehicles.

[0035] Synchronous sampling and differential yaw calculation: During vehicle operation, the vehicle control unit (VCU) simultaneously collects the yaw rate of the steering component and the yaw rate of the main frame at a sampling frequency not less than 10 times the upper limit of the target yaw frequency band and not less than 200 Hz. In one specific parameter configuration, the sampling frequency can be set to 500 Hz to 1000 Hz.

[0036] In addition to yaw rate, the vehicle control unit (VCU) also simultaneously acquires one or more of the following: vehicle speed, front wheel speed, rear wheel speed, estimated vehicle speed, front wheel slip ratio, rear wheel slip ratio, motor back electromotive force, throttle signal, mechanical braking signal, electronic braking signal, remote control braking signal, emergency stop command, front wheel motor current, rear wheel motor current, and occupant status signal, in order to eliminate interference caused by low-speed operation, tire slippage, and sudden changes in braking input when judging high-frequency yaw.

[0037] The vehicle control unit (VCU) calculates the differential yaw rate using the following formula. : In the formula, This represents the yaw rate of the steering component acquired by the first inertial measurement node. This represents the yaw rate of the main frame collected by the second inertial measurement node. This represents the differential yaw rate of the front steering assembly relative to the chassis mainframe.

[0038] The differential yaw rate was calculated. Then, it undergoes zero-bias removal, gravity coupling removal, and outlier elimination. During normal lane changes, cornering, or overall chassis swaying, the front steering component and the chassis backbone typically maintain a certain degree of coordinated movement, with their yaw rates exhibiting similar directions and periods of change. The differential yaw rate... Relatively small, or mainly exhibiting low-frequency changes; when the current steering component undergoes high-frequency alternating swaying relative to the main frame, the differential yaw rate... The energy within the target oscillation frequency band increases accordingly.

[0039] The vehicle control unit (VCU) can also calculate the yaw rate of the steering components. Yaw rate of the main frame Correlation coefficient between them: ; When the steering component and the main frame move in the same phase and cooperate, their correlation remains within the normal range specified for the corresponding vehicle model. When the steering component generates high-frequency alternating swaying relative to the main frame, the energy of the differential yaw rate in the target sway frequency band increases, while the correlation coefficient decreases relative to the cooperative motion state. Therefore, the correlation coefficient can be used as an auxiliary judgment quantity for high-frequency sway identification.

[0040] Target band filtering and oscillation feature extraction: The vehicle control unit (VCU) processes the pre-processed differential yaw rate. Perform bandpass filtering on the target oscillation frequency band to obtain the oscillation signal. ,in, Indicates time.

[0041] Target oscillation frequency band analysis can employ IIR bandpass filtering, FIR bandpass filtering, short-time Fourier transform, or the sliding Goertzel algorithm. The oscillation envelope can be extracted through rectification, Hilbert transform, or sliding peak method. Phase information can be obtained through phase-locked loop phase tracking or corresponding frequency domain analysis results. Different algorithms can be selected based on the computing power and sampling period of the vehicle control unit (VCU), without changing the processing objective of identifying abnormal high-frequency oscillations using the target oscillation frequency band.

[0042] The vehicle control unit (VCU) uses the shimmy signal as a basis. Calculate the energy of the frequency band Filtered oscillation envelope amplitude Envelope growth rate Target oscillation frequency and phase stability.

[0043] Envelope growth rate It can be determined according to the following formula: Alternatively, it can be determined based on the ratio of the shimmy envelope amplitudes of adjacent cycles or adjacent half cycles. The vehicle control unit (VCU) uses this to determine whether the shimmy amplitude gradually decreases, remains stable, or continues to increase, avoiding intervention decisions based solely on the vibration peak value at a single moment.

[0044] High-frequency oscillation confirmed: The confirmation of high-frequency oscillation is based on a combination of frequency, amplitude, growth rate, phase, and vehicle speed. The judgment criteria include: Swing signal Target oscillation frequency Located within the target oscillation frequency band specified by the vehicle model; Filtered oscillation envelope amplitude Greater than the first risk threshold ,Right now: >; Envelope growth rate Greater than the growth threshold ,Right now: ; Or continuous The amplitude of the pendulum oscillation for one and a half cycles satisfies: ; In the formula, This indicates the number of half-cycles in a continuous decision. Indicates the half-cycle sequence number. Indicates the first The amplitude of the pendulum oscillation over one and a half cycles. Indicates the first The amplitude of the pendulum oscillation over one and a half cycles. This indicates the percentage increase in amplitude between adjacent half-cycles.

[0045] Simultaneously, the phase drift between adjacent cycles is less than a set threshold, and the vehicle speed is higher than the speed threshold calibrated by the vehicle model. The speed threshold can be set to 15 km / h, or it can be calibrated separately based on the vehicle model test results.

[0046] Road surface gravel or joint impacts may generate large instantaneous yaw velocities, but their frequency, envelope, and phase usually do not have a continuous and stable relationship; high-frequency shimmy, on the other hand, exhibits continuous alternating changes within the target shimmy frequency band, accompanied by envelope growth and stable phase relationship; the vehicle control unit (VCU) uses the above conditions in combination to distinguish between random road surface impacts and high-frequency shimmy with a divergent trend.

[0047] Oscillation Risk State Machine: The vehicle control unit (VCU) determines the frequency hit rate and bandwidth energy based on frequency hit rate and bandwidth energy. Filtered oscillation envelope amplitude Envelope growth rate And determine the risk level of oscillation based on phase stability. It controls the oscillation risk state machine to switch between S0 normal state, S1 early warning state, S2 confirmation state, S3 intervention state, S4 release state and S5 degraded state.

[0048] When no divergent characteristics are detected in the target oscillation frequency band, the state machine is in the S0 normal state, and the vehicle control unit (VCU) sends commands to the front and rear wheel FOC controllers according to the normal throttle, braking and drive control logic. When the energy in the target shimmy frequency band begins to rise, the state machine changes from the S0 normal state to the S1 warning state. In this state, the sampling and calculation priority related to shimmy identification is increased, the rise rate of the front wheel electronic braking torque or front wheel regenerative braking torque controlled by the vehicle control unit (VCU) is limited, and torque intervention is prepared. When the target oscillation frequency Located within the target oscillation frequency band, the amplitude of the oscillation envelope after filtering When the corresponding threshold is exceeded and the envelope divergence condition is met for a consecutive preset period, the state machine enters the S2 confirmation state. In this state, the amplitude or slope of sudden changes in throttle, sudden changes in wireless control, and sudden changes in electronic braking commands or regenerative braking commands controlled by the vehicle control unit (VCU) are limited. The mechanical braking that does not directly apply to the rider is processed, and the amplitude and phase of the intervention torque are calculated. If the high-frequency oscillation confirmation condition disappears, the state machine returns to the S1 warning state. When the risk level of oscillation When the intervention threshold is exceeded, the state machine enters the S3 intervention state, and the vehicle control unit (VCU) controls the front-wheel drive motor and the rear-wheel drive motor to perform the corresponding torque damping intervention. When the amplitude of the oscillation envelope after filtering Drop below the release threshold and remain During each cycle, the state machine enters the S4 release state and gradually cancels the oscillation intervention item according to the preset slope; if the oscillation diverges again during the release process, it returns to the S2 confirmation state or the S3 intervention state; if the oscillation remains stable, it returns to the S0 normal state. In the S5 downgraded state, the vehicle control unit (VCU) remains in an active torque intervention prohibited state. When the fault is confirmed to be resolved through fault diagnosis, and the occupants are in a stable riding state and the vehicle speed is within a safe range, the state machine will maintain a preset recovery time and return to the S0 normal state after receiving a re-enable command or a fault latch release signal.

[0049] Front and rear wheel torque damping intervention: When the shimmy risk state machine enters the S3 intervention state, the vehicle control unit (VCU) determines the shimmy risk level based on the intervention state. oscillation signal Based on the phase, vehicle speed, tire adhesion estimation, and occupant status, the target torque for the front wheels is issued to the front wheel FOC controller and the rear wheel FOC controller. and target torque for rear wheels The shimmy intervention is superimposed on the normal drive torque or normal braking torque; the intervention methods include longitudinal tension mode, rear wheel steady traction mode and phase-locked torque ripple mode.

[0050] (1) Longitudinal tension mode In longitudinal tension mode, the front-wheel drive motor applies a positive micro-traction torque, the rear-wheel drive motor applies a regenerative anti-drag torque, and the target torque for the front wheels... and target torque for rear wheels satisfy: ; ; ; In the formula, Indicates the magnitude of the intervention torque. It represents the ratio between the regenerative reverse torque of the rear wheels and the positive micro-traction torque of the front wheels.

[0051] The vehicle control unit (VCU) determines the available torque of the front and rear wheels, motor current, battery power, and tire adhesion status. Intervene the torque amplitude and limit the target torque for the front wheels. and target torque for rear wheels The change in net longitudinal acceleration of the vehicle after being output by the corresponding drive motor does not exceed the set safety threshold; this mode creates a controlled longitudinal force difference between the front wheel contact point and the rear wheel contact point, while limiting the acceleration or deceleration changes of the vehicle as a whole.

[0052] (2) Rear wheel steady speed traction mode When no driving torque is applied to the front wheels, the rear wheel drive motor is controlled to output a limited traction torque or a limited regenerative anti-drag torque to maintain vehicle speed, and the rise rate of the front wheel electronic braking torque or front wheel regenerative braking torque controlled by the vehicle control unit (VCU) is limited.

[0053] (3) Phase-locked torque ripple mode The vehicle control unit (VCU) uses the shimmy signal as a basis. Based on the phase estimation results, inject AC torque components into the front-wheel drive motor or the rear-wheel drive motor. AC torque component The timing of the torque application is opposite to the phase of the oscillation or has a preset phase difference, so that the timing of the torque application matches the oscillation period.

[0054] AC torque component Limited by motor current, battery power, tire adhesion, and occupant status; when any of the above parameters reaches the protection condition, the vehicle control unit (VCU) reduces or stops the AC torque component and does not continue to execute phase-locked torque ripple.

[0055] All of the aforementioned torque interventions are configured with maximum amplitude, maximum rate of change, maximum duration, temperature protection threshold, and current protection threshold. The duration of a single intervention is calibrated within the range of 0.1 s to 1.0 s, and the upper limit of the torque for a single intervention is calibrated within the range of 5% to 30% of the currently available drive torque. Specific parameters are determined by vehicle model, motor output capability, battery status, and road adhesion conditions.

[0056] Brake input processing: In the S1 warning state to the S3 intervention state, the vehicle control unit (VCU) only limits the amplitude or slope of the electronic braking or regenerative braking commands it can control, and does not restrict the mechanical braking directly applied by the rider. When a forced front braking or emergency braking command is detected, the VCU limits the rise slope of the front wheel electronic braking torque or front wheel regenerative braking torque according to the shimmy risk level, and redistributes the front and rear wheel electronic braking torque according to the front and rear wheel speeds, slip ratios, and available regenerative braking capabilities.

[0057] When the occupant is stable and the shimmy envelope is still rising, the priority of the front wheel electronic braking or regenerative braking can be reduced for a preset duration. When occupant instability, obstacle collision risk, tire adhesion not meeting the intervention conditions, rapid vehicle speed drop, FOC failure, or battery failure is detected, the vehicle control unit (VCU) stops the aforementioned priority adjustment and switches to a safety-first degraded braking strategy.

[0058] Occupant status detection and degradation control: The vehicle can be equipped with an occupant status detection module, which includes a pedal pressure sensor, a micro-strain array in the foot pedal area, a grip detection device, or a foot pedal area load detection device. The occupant status can be determined by combining the motor load, sudden changes in vehicle posture, or remote control release signal.

[0059] The vehicle control unit (VCU) uses at least two independent occupant status signals for joint judgment. When at least two of these signals meet the corresponding instability criteria, the occupant is determined to be in an unstable state. Specifically, pedal pressure sensors or micro-strain arrays in the foot pedal area can be used to determine the magnitude, rate, or change in the pressure center trajectory of the occupant's foot load; vehicle attitude signals can be used to determine the rate of change of the vehicle tilt angle. The magnitude or rate of the occupant's foot load descent exceeding a preset threshold, the pressure center trajectory deviating from a preset stability range, or the rate of change of the vehicle tilt angle exceeding a preset threshold can be used as instability criteria for the corresponding occupant status signal.

[0060] When only one occupant status signal meets the corresponding instability judgment condition, while other independent occupant status signals do not meet the corresponding instability judgment condition, the vehicle control unit (VCU) continues to acquire occupant status signals but does not directly determine occupant instability based on them; when at least two mutually independent occupant status signals meet the corresponding instability judgment condition, occupant instability is determined and the shimmy risk state machine enters the S5 degraded state.

[0061] In the S5 degraded state, the vehicle control unit (VCU) remains in an active torque intervention prohibited state and performs fault diagnosis on the inertial measurement node, front and rear wheel FOC controllers, battery status, and occupant status. Only when the fault diagnosis indicates that the corresponding fault has been resolved, the occupant is in a stable riding state, the vehicle speed is within a safe range, and the above recovery conditions are maintained for a preset recovery time, is the vehicle allowed to enter the recovery standby state. Upon receiving a re-enable command or detecting a fault latch release signal, the VCU restores the shimmy risk state machine to the S0 normal state. If the recovery conditions are not continuously met, the fault recurs, or no re-enable signal is received, the S5 degraded state is maintained.

[0062] Example 1 This embodiment takes a dual-drive high-speed off-road scooter as an example. The first inertial measurement node is installed on the upper end of the steering column, and the second inertial measurement node is installed at the center of the pedal main beam. After the two inertial measurement nodes complete timestamp synchronization, zero-bias correction, coordinate system alignment, and sampling delay compensation, they collect the yaw rate of the steering component at the same sampling frequency. and the yaw rate of the frame backbone .

[0063] In an exemplary driving scenario, when the vehicle passes through a continuous road joint at 45 km / h, the signal collected by the second inertial measurement node mainly shows random vibration of the main frame, while the signal collected by the first inertial measurement node shows an alternating yaw component of about 7 Hz. The vehicle control unit (VCU) calculates the differential yaw rate. The signal was then subjected to a 5 Hz to 12 Hz bandpass filter to obtain the oscillation signal. .

[0064] When the dominant frequency of the shimmy signal is within the target shimmy frequency band, the shimmy envelope shows an increasing trend for four and a half consecutive cycles, and the phase drift of adjacent cycles is less than the set threshold, the vehicle control unit (VCU) identifies it as a high-frequency shimmy with a diverging trend and controls the shimmy risk state machine to enter the S2 confirmation state; when the shimmy envelope does not increase continuously or the phase relationship does not meet the set conditions, the shimmy risk state machine does not enter the S2 confirmation state and continues to monitor the shimmy risk. In this embodiment, 45 km / h, approximately 7 Hz, 5 Hz to 12 Hz, and four consecutive half-cycles are used to illustrate a control parameter configuration. The specific vehicle speed threshold, target oscillation frequency band, and continuous judgment period are determined based on the vehicle model and calibration results.

[0065] Example 2 In the scenario identified in Example 1, when the oscillation envelope continues to grow and the oscillation risk level... When the intervention threshold is exceeded, the oscillation risk state machine changes from the S2 confirmation state to the S3 intervention state.

[0066] The vehicle control unit (VCU) uses longitudinal tension mode to send positive micro-traction torque commands to the front wheel FOC controller. Send regenerative anti-drag torque command to the rear wheel FOC controller The intervention torque amplitude is determined based on the vehicle's current speed, available drive torque, and motor current. and proportionality coefficient At the same time, it limits the change in the vehicle's net longitudinal acceleration caused by the output of the target torque of the front wheels and the target torque of the rear wheels through the corresponding drive motors.

[0067] During torque intervention, the vehicle control unit (VCU) continuously calculates the filtered shimmy envelope amplitude; when the shimmy envelope amplitude... When the shimmy risk state machine drops below the release threshold and remains at the preset period, it enters the S4 release state. The vehicle control unit (VCU) gradually cancels the positive micro-traction torque of the front wheel and the regenerated reverse drag torque of the rear wheel according to the preset slope, and resumes normal riding control. When the shimmy envelope amplitude does not decrease or shows an increasing trend again, the VCU maintains the S3 intervention state or recalculates the intervention torque. When the protection threshold of intervention duration, current, temperature or torque amplitude is reached, the current intervention is exited and the corresponding protection state is entered.

[0068] Example 3 When the vehicle is in the S2 confirmation state and a rider inputs a front wheel emergency braking command, the vehicle control unit (VCU) limits the rate of increase of the front wheel electronic braking torque or the front wheel regenerative braking torque, and redistributes the front and rear wheel electronic braking torque according to the front and rear wheel speeds, slip ratios, and available regenerative braking capabilities, handling mechanical braking that is not directly applied by the rider; when the safety priority conditions are met, the aforementioned priority adjustment is stopped and a degraded braking strategy is adopted.

[0069] Example 4 When the vehicle performs torque intervention, the vehicle control unit (VCU) simultaneously acquires the occupant foot load signal output by the pedal micro-strain array or pressure sensor, and the vehicle attitude signal output by the second inertial measurement node. In this embodiment, when the occupant foot load decreases by an amplitude or rate exceeding a corresponding preset threshold, and the rate of change of the vehicle tilt angle also exceeds a corresponding preset threshold, both independent occupant state signals meet the instability determination condition. Based on this, the VCU determines that the occupant is unstable and causes the shimmy risk state machine to enter the S5 degraded state.

[0070] If only one of the occupant foot load signal or vehicle attitude signal meets the corresponding instability judgment condition, the occupant is not directly judged to be unstable. The vehicle control unit (VCU) continues to acquire the occupant status signal and maintain the current status judgment.

[0071] In the S5 downgraded state, the vehicle control unit (VCU) remains in an active torque intervention prohibited state. When the fault is confirmed to be resolved through fault diagnosis, and the occupants are in a stable riding state and the vehicle speed is below the preset safe speed threshold, the preset recovery time is maintained continuously. After receiving at least one of the re-enable command or fault latch release signal, the shimmy risk state machine returns to the S0 normal state.

[0072] The specific installation locations of the first and second inertial measurement nodes, the determination method of the target yaw frequency band, and the frequency domain analysis method can be adjusted according to the vehicle structure and the computing power of the controller. The occupant status can be jointly determined by at least two independent signals from pedal pressure, foot pedal area micro-strain array, vehicle grip, motor load, sudden change in vehicle attitude, or remote control release detection. All the above adjustments are based on the differential yaw recognition of the front steering assembly and the main frame, the divergence confirmation within the target yaw frequency band, and the torque damping intervention of the front and rear wheels.

[0073] 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 person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in the present invention, and these should all 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.

Claims

1. A method for high-frequency swaying identification and torque damping control of a dual-drive, single-track vehicle, characterized in that, This method is applied to single-track or narrow-track micro-vehicles where the front and rear wheels are driven by front-wheel drive motors and rear-wheel drive motors respectively, and the front and rear wheels are approximately collinear. The process is executed by the vehicle control unit (VCU) and includes the following steps: S1. Obtain the target sway frequency band calibrated by the vehicle model, and perform time stamp synchronization, zero bias correction, coordinate system alignment and sampling delay compensation on the first inertial measurement node rigidly connected to the front steering component and the second inertial measurement node rigidly connected to the frame main body or pedal load-bearing structure. S2. Synchronously acquire the yaw rate of the steering component output by the first inertial measurement node. The yaw rate of the main frame output by the second inertial measurement node The vehicle's speed, front wheel speed, and rear wheel speed, according to Calculate the differential yaw rate and the differential yaw rate Preprocessing is required; S3, Processed differential yaw rate The target shimmy frequency band was bandpass filtered according to the vehicle model calibration to obtain the filtered shimmy signal. And according to the oscillation signal Calculate the energy of the frequency band Filtered oscillation envelope amplitude Envelope growth rate Target oscillation frequency and phase stability; S4. Based on the target oscillation frequency Whether it is located within the target oscillation frequency band, and the amplitude of the filtered oscillation envelope. The envelope growth rate The phase stability and the vehicle speed determine the shimmy risk level. And according to the said oscillation risk level The oscillation risk state machine switches between the S0 normal state, S1 warning state, S2 confirmation state, S3 intervention state, S4 release state, and S5 degraded state. S5, when the aforementioned oscillation risk level When the intervention threshold is exceeded and the S3 intervention state is entered, the oscillation risk level is determined accordingly. The oscillation signal Based on the phase, vehicle speed, tire adhesion estimation, and occupant status, the target torque for the front wheels is issued to the front wheel FOC controller and the rear wheel FOC controller. and target torque for rear wheels Control the front-wheel drive motor and the rear-wheel drive motor to execute at least one of the longitudinal tension mode, the rear-wheel steady-speed traction mode or the phase-locked torque ripple mode, superimpose the shimmy intervention term onto the normal drive torque or the normal braking torque, and limit the amplitude, rate of change, duration and net longitudinal acceleration change of the intervention torque. S6, when the filtered oscillation envelope amplitude When the speed drops below the release threshold and remains below the preset cycle, the sway intervention is gradually withdrawn according to the preset slope and normal riding control is restored. When occupant instability, inertial measurement node failure, FOC failure or battery failure is detected, the system enters the S5 degraded state, stops the longitudinal tension mode and phase-locked torque ripple mode, and switches to power-limited coasting, amplitude-limited braking or power-off protection.

2. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The vehicle control unit (VCU) acquires the yaw rate of the steering assembly and the yaw rate of the main frame at a sampling frequency not less than 10 times the upper limit frequency of the target yaw frequency band and not less than 200 Hz. The preprocessing includes zero bias removal, gravity coupling removal, and outlier removal. The vehicle operation signals acquired synchronously also include at least one of the following: estimated vehicle speed, front wheel slip ratio, rear wheel slip ratio, motor back EMF, throttle signal, mechanical braking signal, electronic braking signal, remote control braking signal, emergency stop command, front wheel motor current, rear wheel motor current, and occupant status signal.

3. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The first inertial measurement node is rigidly connected to the handlebars, steering column, front fork axle, front wheel motor housing, or a structure fixedly connected to the front steering assembly, and is used to collect the yaw rate, lateral acceleration, or steering angle-related dynamics of the front steering assembly; the second inertial measurement node is rigidly connected to the frame main beam, the middle of the pedals, the battery pack housing, or a structural component near the vehicle's center of gravity, and is used to collect the overall yaw rate, lateral acceleration, and attitude information of the frame.

4. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The vehicle control unit (VCU) also calculates correlation coefficients. and the correlation coefficient With the differential yaw rate The energy within the target sway frequency band is used to identify the high-frequency alternating swaying of the front steering assembly relative to the frame main body; when the differential energy within the target sway frequency band increases and the correlation coefficient decreases relative to the coordinated motion state of the front steering assembly and the frame main body, it is used as one of the criteria for determining the high-frequency alternating swaying.

5. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The target yaw frequency band calibrated by the vehicle model is a sub-interval within the range of 4 Hz to 14 Hz, and the target yaw frequency band is determined through factory frequency sweep testing or road test data; when the target yaw frequency band is 5 Hz to 12 Hz, the differential yaw rate is... Frequency domain analysis is performed using IIR bandpass filtering, FIR bandpass filtering, short-time Fourier transform, or sliding Goertzel algorithm. Envelope or phase features are obtained by rectification, Hilbert transform, sliding peak extraction, or phase-locked loop phase tracking.

6. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The filtered oscillation envelope amplitude The envelope growth rate is obtained through rectification, Hilbert transform, or sliding peak extraction. according to Calculate, where, It can be expressed as time, or determined based on the amplitude ratio of adjacent periods.

7. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The confirmation criteria for high-frequency oscillation include: the target oscillation frequency. Located within the target oscillation frequency band specified by the vehicle model; The filtered oscillation envelope amplitude Greater than the first risk threshold ; The envelope growth rate Greater than the growth threshold or continuous One and a half cycles satisfy The phase drift between adjacent cycles is less than a set threshold. The vehicle's speed exceeds 15 km / h or is higher than the speed threshold specified by the vehicle model; wherein, This indicates the number of half-cycles in a continuous judgment. Indicates the first The amplitude of one and a half cycles, Indicates the first The amplitude of one and a half cycles, This indicates the percentage increase in amplitude between adjacent half-cycles.

8. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The oscillation risk state machine is in the S0 normal state when no divergence characteristics are detected within the target oscillation frequency band, and enters the S1 warning state when an energy increase within the target oscillation frequency is detected. Located within the target oscillation frequency band and the filtered oscillation envelope amplitude When the threshold is exceeded, the S1 warning state is maintained. When the envelope divergence condition is met for a consecutive preset period, the state transitions from the S1 warning state to the S2 confirmation state, which is the oscillation risk level. When the threshold is exceeded, the system transitions from the S2 confirmation state to the S3 intervention state, where the amplitude of the filtered oscillation envelope is... Below the release threshold and remain During each cycle, it transitions from the S3 intervention state to the S4 release state, and enters the S5 degradation state upon detecting occupant load loss, FOC failure, battery failure, or sensor malfunction. Indicates the number of consecutive oscillation cycles maintained during the execution of the release decision; When the energy in the target oscillation frequency band decreases under the S1 warning state, it returns to the S0 normal state. When the high-frequency oscillation confirmation condition disappears under the S2 confirmation state, it returns to the S1 warning state. When the high-frequency oscillation diverges again under the S4 release state, it returns to the S2 confirmation state or the S3 intervention state. When the high-frequency oscillation remains stable, it returns to the S0 normal state.

9. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The longitudinal tension mode includes: controlling the front-wheel drive motor to apply a positive micro-traction torque during a preset intervention period, and controlling the rear-wheel drive motor to apply a regenerative anti-drag torque, wherein the target torque of the front wheels... and the target torque of the rear wheels They respectively satisfy: ； ； ； In the formula, Indicates the magnitude of the intervention torque. This represents the ratio of the rear wheel regenerative drag torque amplitude to the front wheel positive micro-traction torque amplitude; the vehicle control unit (VCU) controls the intervention torque amplitude. Limit the torque applied to the front wheels and restrict the target torque. and the target torque of the rear wheels The change in net longitudinal acceleration of the vehicle after being output by the corresponding drive motor does not exceed the set safety threshold.

10. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The rear wheel steady-speed traction mode includes: when no driving torque is applied to the front wheels, controlling the rear wheel drive motor to output a limited traction torque or a limited regenerative reverse drag torque to maintain vehicle speed, and limiting the rise slope of the front wheel electronic braking torque or front wheel regenerative braking torque controlled by the vehicle control unit (VCU).

11. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The phase-locked torque ripple mode includes: the vehicle control unit (VCU) based on the shimmy signal. Phase estimation is performed to inject an AC torque component that is opposite in phase to the oscillation or has a preset phase difference into the front-wheel drive motor or the rear-wheel drive motor. The AC torque component It is limited by motor current, battery power, tire adhesion and occupant status.

12. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The longest duration of a single torque intervention is calibrated in the range of 0.1s to 1.0s, and the upper limit of the single intervention torque is calibrated in the range of 5% to 30% of the currently available drive torque. The intervention torque is also limited by the maximum rate of change, temperature protection threshold and current protection threshold, and the net longitudinal acceleration change generated during the intervention does not exceed the set safety threshold.

13. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 8, characterized in that, From S1 warning state to S3 intervention state, sudden changes in throttle, wireless control, and electronic or regenerative braking commands controlled by the vehicle control unit (VCU) are processed by limiting amplitude or slope; when a rider inputs a forced forward braking or emergency braking command, the sway risk level is determined. Limit the rise rate of the front wheel electronic braking torque or the front wheel regenerative braking torque, and redistribute the front and rear wheel electronic braking torque. The limiting or slope limiting process does not apply to the mechanical braking directly applied by the rider. When the occupant's condition is stable and the amplitude of the filtered oscillation envelope is... While the pressure is still rising, the priority of the front wheel electronic braking or regenerative braking controlled by the vehicle control unit (VCU) is reduced for a preset duration. When occupant instability, obstacle collision risk, tire adhesion not meeting intervention conditions, sudden drop in vehicle speed, FOC failure, or battery failure are detected, the reduction of the front wheel electronic braking or regenerative braking priority is stopped, and a safety-priority degraded braking strategy is switched to.

14. The method for high-frequency sway identification and torque damping control of a dual-drive single-track vehicle according to claim 1, characterized in that, The occupant state is determined by at least two independent signals from the following sources: pedal pressure sensor, foot pedal area micro-strain array, vehicle grip detection, motor load, sudden change in vehicle posture, or remote control release detection. When at least two independent occupant state signals meet the corresponding instability judgment conditions, the occupant is determined to be instable and the sway risk state machine is put into the S5 degraded state. The instability judgment conditions include the occupant's two-foot load decreasing amplitude or decreasing rate exceeding a preset threshold, the pressure center trajectory deviating from a preset stable range, or the rate of change of the vehicle tilt angle exceeding a preset threshold.

15. The method for high-frequency swaying identification and torque damping control of a dual-drive single-track vehicle according to claim 14, characterized in that, In the S5 degraded state, the longitudinal tension mode and phase-locked torque ripple mode are stopped, and the rear wheel braking or power-off protection with limited power coasting, limited amplitude and limited slope is switched to. When the vehicle control unit (VCU) confirms that the fault has been cleared through fault diagnosis, and the occupant is in a stable riding state and the vehicle speed is within a safe range, the preset recovery time is maintained. After receiving a re-enable command or fault latch release signal, the S5 degraded state is released, and the shimmy risk state machine is restored to the S0 normal state.

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