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

Abstract

The invention 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 steps that S1, multi-source hub sensing signals of all wheels are synchronously collected; s2, calculating a hub response coupling factor based on the multi-source hub sensing signal; s3, calculating an instantaneous slip rate based on the coupling factor and the wheel speed in combination with vehicle dynamic parameters; s4, on the basis of the wheel speed, the braking torque and the tangential acceleration, the coupling factor and the instantaneous slip rate are combined, and the normal load is calculated; s5, calculating an adhesion coefficient according to the instantaneous slip rate, the normal load and the wheel speed; s6, according to the slip rate deviation, a fusion weight is generated in combination with the coupling factor, and the adhesion capacity of the whole vehicle is calculated; and S7, according to the adhesion coefficient, the normal load, the slip rate and the adhesion capacity of the whole vehicle, the target braking force is calculated, and the wheel braking strength is adjusted. By monitoring the state of the wheels in real time, the slip rate is accurately controlled, braking force distribution is optimized, and the response precision and stability of the ABS 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 maneuverability of vehicles by preventing wheel lock during emergency braking. However, the performance of traditional ABS systems under complex road conditions still has deficiencies, 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 changing road conditions and adhesion changes 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 under 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: 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; S2: calculating wheel hub response coupling factors of the wheels based on the multi-source wheel hub sensor signals; S3: calculating instantaneous slip rates of the wheels based on the wheel hub response coupling factors and the wheel speed signals, in combination with the vehicle longitudinal speed and the 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; S5: According to the instantaneous slip rate, the normal load and the wheel speed signal, the adhesion coefficient of the wheel is calculated; S6: According to the deviation of the instantaneous slip rate of each wheel and the preset target slip rate, the fusion weight is generated combined with the hub response coupling factor, and the whole vehicle adhesion capacity is calculated; S7: According to the adhesion coefficient of each wheel, the normal load, the instantaneous slip rate and the whole vehicle adhesion capacity, the target brake force is calculated, and the brake intensity of each wheel is adjusted according to the target brake force.

[0007] The application is further provided that the S2 comprises: 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 the sensor; According to the time sequence difference operation of the wheel speed signal, the acceleration characteristics of the dynamic change of the wheel speed are extracted; Based on the differential cumulative amount of the radial acceleration signal, the radial vibration intensity characteristics of the hub are calculated; According to the absolute value of the product of the tangential acceleration signal and the brake torque signal, the torque and acceleration coupling characteristics are generated; The hub response coupling factor is calculated by comprehensively considering the acceleration characteristics, the vibration intensity characteristics and the coupling characteristics.

[0008] The application is further provided that the S3 comprises: The collected wheel speed signal is dynamically corrected by using the hub response coupling factor; 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.

[0009] The application is further provided that the S4 comprises: The absolute values of the brake torque signal, the tangential acceleration signal and the wheel speed signal corrected by the hub response coupling factor are weighted and superimposed to generate a composite basic load term; The time-varying compression index is calculated by combining the wheel speed signal difference value, the brake torque signal difference value and the instantaneous slip rate difference value; Based on the composite basic load term and the time-varying compression index, the normal load of the wheel is calculated.

[0010] The application is further provided that the S5 comprises: 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 adhesion mapping factor; The absolute difference value between the normal load at the current time and the previous time of the wheel is calculated to obtain a load variation compensation factor; Based on the wheel speed signal, the instantaneous slip rate and the normal load of the wheel, the adhesion coefficient of the wheel is calculated combined with the adhesion mapping factor and the load variation compensation factor.

[0011] The application is further provided that the S6 comprises: Based on the absolute value of the deviation of the instantaneous slip ratio of each wheel from the preset target slip ratio, a slip sticking-in degree is generated through an exponential decay characteristic; The slip sticking-in degree and the hub response coupling factor are multiplied to generate a fusion weight of each wheel; Taking the adhesion coefficient of each wheel as a base value, the adhesion capacity of the whole vehicle is calculated by weighting in combination with the corresponding fusion weight.

[0012] The application is further provided that the S7 comprises Based on the difference between the adhesion capacity of the whole vehicle and the preset reference adhesion capacity, the control slip ratio reference value is calculated in combination with the preset target slip ratio; According to the absolute value of the deviation of the control slip ratio reference value from the instantaneous slip ratio, a slip error influence term with a decay characteristic is constructed; Based on the difference between the maximum allowable braking force and the braking force at the previous moment, a braking force mutation suppression term with an S-shaped saturation characteristic is constructed; The target braking force is obtained by nonlinearly combining the adhesion coefficient of the wheel, the normal load, the slip error influence term and the braking force mutation suppression term.

[0013] The application is further provided that based on the deviation between the control slip ratio reference value and the instantaneous slip ratio of each wheel, the slip ratio error accumulation index is calculated 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 the preset error threshold value, the adaptive update of the control slip ratio reference value is started; Based on the difference between the slip ratio error accumulation index and the preset error threshold value, the updated control slip ratio reference value is calculated in combination with the control slip ratio reference value at the previous moment.

[0014] The application is further provided that the target braking force is dynamically adjusted according to the updated control slip ratio reference value.

[0015] The application also provides an ABS real-time adaptive control system based on hub sensor signal fusion, which comprises: A data acquisition module is used to synchronously acquire multi-source hub sensor signals of each wheel, and the multi-source hub sensor signals include wheel speed signals, radial acceleration signals, tangential acceleration signals and braking torque signals; A hub response calculation module is used to calculate the hub response coupling factor of the wheel based on the dynamic response characteristics of the multi-source hub sensor signals; An instantaneous slip ratio calculation module is used to calculate the instantaneous slip ratio of the wheel based on the hub response coupling factor and the wheel speed signal in combination with the vehicle longitudinal speed and the tire rolling radius; Normal load calculation module: for calculating the normal load of the wheel based on the wheel speed signal, the braking torque signal and the tangential acceleration signal, in combination with the hub response coupling factor and the instantaneous slip rate; Adhesion coefficient calculation module: for calculating the adhesion coefficient of the wheel according to the instantaneous slip rate, the normal load and the wheel speed signal; Adhesion capacity calculation module: for calculating the adhesion capacity of the whole vehicle 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, to generate a fusion weight; Target braking force calculation module: for calculating the target braking force according to the adhesion coefficient of each wheel, the normal load, the instantaneous slip rate and the adhesion capacity of the whole vehicle, and adjusting the braking intensity of each wheel according to the target braking force.

[0016] The present application provides an ABS real-time adaptive control method and system based on hub sensor signal fusion, which comprises the following steps: S1: synchronously collecting multi-source hub sensor signals of each wheel, wherein the multi-source hub sensor signals comprise wheel speed signals, radial acceleration signals, tangential acceleration signals and braking torque signals; S2: calculating a hub response coupling factor of the wheel based on the multi-source hub sensor signals; S3: calculating an instantaneous slip rate of the wheel based on the hub response coupling factor and the wheel speed signal, in combination with the vehicle longitudinal speed and the tire rolling radius; S4: calculating a normal load of the wheel based on the wheel speed signal, the braking torque signal and the tangential acceleration signal, in combination with the hub response coupling factor and the instantaneous slip rate; S5: calculating an adhesion coefficient of the wheel according to the instantaneous slip rate, the normal load and the wheel speed signal; S6: calculating the adhesion capacity of the whole vehicle 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, to generate a fusion weight; S7: calculating a target braking force according to the adhesion coefficient of each wheel, the normal load, the instantaneous slip rate and the adhesion capacity of the whole vehicle, and adjusting the braking intensity of each wheel according to the target braking force, which has the following beneficial effects: 1. Real-time wheel state monitoring and control: through synchronous collection of multi-source hub sensor signals, the wheel speed, acceleration, braking torque and other physical signals of the wheel are monitored in real time, which can fully reflect the dynamic state of the wheel and ensure real-time control of the ABS system on the tire adhesion state; through accurate calculation of the hub response coupling factor, the working state of the wheel can be timely and accurately evaluated by the control system; 2. Improved slip rate control accuracy: based on the difference between the instantaneous slip rate and the historical instantaneous slip rate of the wheel, in combination with the dynamic correction of the hub response coupling factor, the slip rate of each wheel can be accurately calculated, and the ABS system can be adjusted in real time; when there is a large deviation between the slip rate and the preset target slip rate, the slip rate reference value is adjusted adaptively, which effectively improves the braking performance of the vehicle and improves the stability and safety of the vehicle; 3. Optimizing the distribution of braking force: By calculating multiple parameters such as the adhesion coefficient of the wheel, the normal load, the instantaneous slip rate, and the total adhesion capacity of the vehicle, the distribution of braking force can be optimized in real time, ensuring that the braking force is reasonably distributed among different wheels, effectively preventing excessive or insufficient braking force, thereby optimizing the braking response and stability of the vehicle.

[0017] The above description is only a summary of the technical solutions of the present application. In order to more clearly understand the technical means of the present application, the content of the specification can be implemented, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor. In the drawings: Figure 1 The flow chart of the ABS real-time adaptive control method based on wheel hub sensor signal fusion shown for an exemplary embodiment of the present application; Figure 2 The structural schematic diagram of the ABS real-time adaptive control system based on wheel hub sensor signal fusion shown for an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0019] The embodiments of the present application will be described below with reference to the drawings and preferred embodiments, and those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in the specification. The present application can also be implemented or applied by different specific embodiments, and the details in the specification can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be understood that the preferred embodiments are only for illustration of the present application, and are not intended to limit the protection scope of the present application.

[0020] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present application in a schematic manner, and only the components related to the present application are shown in the diagrams, not the number, shape and size of the components when actually implemented. The actual implementation of each component may be a random change in shape, number and proportion, and the layout pattern of the components may also be more complex.

[0021] In the following description, numerous specific details are discussed in order to provide a thorough understanding of the embodiments of the application. However, those skilled in the art will recognize that the embodiments of the application can be practiced without these specific details. In other instances, well-known structures and devices are not described in detail in order to avoid obscuring the embodiments of the application.

[0022] Embodiment one The ABS real-time adaptive control method based on hub sensor signal fusion, as shown in the figure, comprises: Figure 1 S1: synchronously collecting multi-source hub sensor signals of each wheel, the multi-source hub sensor signals comprising wheel speed signals, radial acceleration signals, tangential acceleration signals and braking torque signals; S2: calculating hub response coupling factors of the wheels based on the multi-source hub sensor signals; S3: calculating instantaneous slip rates of the wheels based on the hub response coupling factors and the wheel speed signals in combination with the vehicle longitudinal speed and the 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 hub response coupling factors and the instantaneous slip rates; 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 according to the deviations of the instantaneous slip rates of the wheels from preset target slip rates in combination with the hub response coupling factors, and calculating the total adhesion capacity; S7: calculating target braking forces according to the adhesion coefficients of the wheels, the normal loads, the instantaneous slip rates and the total adhesion capacity, and adjusting the braking intensities of the wheels according to the target braking forces. The application is further provided with that the S2 comprises:

[0023] synchronously collecting wheel speed signals, radial acceleration signals, tangential acceleration signals and braking torque signals of the hub positions of each wheel through sensors; extracting acceleration characteristics of dynamic changes of the wheel speeds according to time sequence difference operations of the wheel speed signals; calculating hub radial vibration intensity characteristics based on differential accumulations of the radial acceleration signals; generating force moment and acceleration coupling characteristics according to absolute values of products of the tangential acceleration signals and the braking torque signals; comprehensively calculating the hub response coupling factors according to the acceleration characteristics, the vibration intensity characteristics and the coupling characteristics; specifically, the multiple hub sensors synchronously collect multiple signals of the wheels, including wheel speed signals , radial acceleration signals , tangential acceleration signals and braking torque signals and braking torque signals wherein the wheel position the signals corresponding to the four wheels, is the current time; 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 the core sensing parameters, which can realize efficient observation of key states such as tire footprint vertical load, braking torque transmission characteristics and adhesion under the current sensor integration technology level; the acceleration characteristics of dynamic changes in wheel speed are extracted by using the time sequence difference operation of the wheel speed signal, which reflects the acceleration and deceleration rates of the wheel during driving; the radial vibration intensity of the wheel hub is calculated based on the difference accumulation of the radial acceleration signal, which reflects the radial vibration intensity received by the wheel during driving; the coupling characteristics of torque and acceleration are generated by calculating the absolute value of the product of the tangential acceleration signal and the braking torque signal, which reflects the coupling relationship between acceleration and braking effect; according to the above acceleration characteristics, vibration intensity characteristics and coupling characteristics, the wheel hub response coupling factor is calculated, which provides accurate wheel dynamic state evaluation for the system by comprehensive weighted coupling of multiple dynamic signals, and the calculation logic of the wheel hub response coupling factor is: , is the first the wheel hub response coupling factor of the wheel at time ; is the first the wheel speed time sequence second-order difference of the wheel at time , which is used to reflect the change of wheel acceleration, the calculation logic is: , , and are the wheel speed signals of the first wheel at times , and ; is the radial acceleration signal difference accumulation of the first wheel at time , which is used to measure the vibration excitation intensity of the wheel during driving, the calculation logic is: , is the difference index, and the range of in the formula is from 0 to 2, indicating that the radial acceleration signal data of the past three times is calculated by difference, and by comparing the signals of different time steps, the dynamic change trend of the wheel acceleration can be effectively captured, thereby reflecting the acceleration or deceleration of the wheel at different time points; and are the tangential acceleration signals of the first wheel at times and The radial acceleration signal, Used to standardize the radial acceleration change to avoid scaling issues caused by time steps or different tire characteristics, ensuring consistency of calculation results; For the Wheels at the moment 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: , For the Wheels at the moment The tangential acceleration signal, For the Wheels at the moment Braking torque signal; is a constant used to prevent the denominator from being zero, and its value range is [0.000001,0.001]; is the adjustment coefficient, which is used to control the rate of change of the hub response coupling factor, and its value range is [0.1,5]; is an adjustment coefficient used to adjust the strength of the wheel hub response coupling factor, with a value range of [0.1, 5]. By synchronously collecting 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, and can fully reflect the real-time dynamic state of the wheel.

[0024] The present invention is further configured such that S3 includes: The collected wheel speed signal is dynamically corrected using the hub response coupling factor; The corrected wheel speed signal is mapped to the vehicle longitudinal speed and tire rolling radius through a nonlinear function to calculate the instantaneous slip rate of each wheel; specifically, the collected wheel speed signal is dynamically corrected by using the wheel hub response coupling factor. Used to correct the original wheel speed signal , so that the wheel speed signal can better reflect the response of the wheel under actual working conditions; the calculation logic of the instantaneous slip rate is: , For the Wheels at the moment The instantaneous slip ratio is used to measure the difference between the wheel speed and the actual vehicle speed; For vehicles at time The longitudinal speed represents the overall speed of the vehicle in the forward direction; For the The rolling radius of the wheel is used to convert the angular velocity of the wheel into a linear velocity for comparison with the longitudinal velocity of the vehicle; is an adjustment coefficient for adjusting the weight of the vehicle longitudinal speed in the instantaneous slip ratio calculation, controlling the sensitivity to the vehicle speed change, and the value range is [0.8, 1.5]; is an adjustment coefficient for adjusting the influence degree of the wheel rolling radius and the wheel speed correction term on the denominator, and the value range is [0.2, 0.8]; is a constant for preventing the abnormality of the instantaneous slip ratio calculation caused by the too small denominator, and the value range is [0.05, 0.3]; , and The specific values of,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, measures the difference between the vehicle speed and the corrected wheel circumferential speed, that is, the speed difference between the wheel and the ground; is used to provide a normalized reference to avoid the nonlinear distortion caused by directly using the vehicle speed, and the correction term and the constant compensation are added; 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, so that the instantaneous slip ratio calculation is more accurate.

[0025] The application further provides that the S4 comprises: The absolute values of the brake torque signal, the absolute value of the tangential acceleration signal and the wheel speed signal corrected by the hub response coupling factor are weighted and superimposed to generate a composite basic load term; 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 ratio difference value; The normal load of the wheel is calculated based on the composite basic load term and the time-varying compression index; specifically, the brake torque at the current time, 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 obtain the composite basic load term, and the composite basic load term can comprehensively reflect the comprehensive external action strength received by the wheel at the current time, and the calculation logic of the composite basic load term is: , is the composite basic load term; is the absolute value of the tangential acceleration signal; is the absolute value of the wheel speed signal corrected by the hub response coupling factor; is a constant for ensuring the numerical stability of the denominator, preventing the abnormal fluctuation of the wheel speed or other signals from causing the distortion of the normal load estimation, and the value range is [0.05, 0.5]; , , and is the adjustment coefficient; It is used to control the nonlinear response intensity of the tangential acceleration to the composite base load term, and the value range is [0.8, 2]; Used to control the influence weight of the tangential acceleration signal on the composite foundation load term, with a value range of [0.1, 2]; It is used to adjust the contribution of the wheel speed signal corrected by the hub response coupling factor to the composite foundation load term. The value range is [0.1, 2]. It is used to control the nonlinear enhancement degree of the composite basic load term by the wheel speed signal after correction by the hub response coupling factor. The value range is [0.5, 2.5]. The wheel speed, braking torque and instantaneous slip rate at the current moment and the previous moment are differentially calculated to obtain the rate of change. The calculation logic of the wheel speed signal differential value is: , For the Wheels at the moment The wheel speed change rate reflects the magnitude of the wheel speed change; and Respectively Wheels at the moment and The calculation logic of the braking torque signal difference value is: , For the Wheels at the moment The braking torque change rate reflects the impact of the braking torque change on the adhesion state; and Respectively Wheels at the moment and The calculation logic of the instantaneous slip rate difference is: , For the Wheels at the moment The instantaneous slip rate change rate 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: , For the Wheels at the moment The time-varying compression index is used to characterize the compression degree of the current road adhesion in a short period of time, making the normal load calculation more sensitive to sudden changes; is the adjustment coefficient, which is used to control the weight of the wheel speed change rate in the time-varying compression index, and its value range is [0.8, 2]; is the adjustment coefficient, which is used to control the weight of the braking torque change rate in the time-varying compression index, and its value range is [0.8, 2]; is the adjustment coefficient, used to The results are subjected to nonlinear transformation, with the value range being [0.5, 1.5]; is a regulating factor used to control the degree to which the instantaneous slip rate of change weakens the time-varying compressibility index, with a value range of [0.05, 2]. The normal load is calculated by combining the composite base load term and the time-varying compressibility index. The normal load represents the force in the vertical direction of contact between the wheel and the ground, which determines the friction between the tire and the ground, and thus affects the vehicle's braking, acceleration, and cornering performance. The calculation logic of the normal load is: , For the Wheels at the moment The calculation of the above normal load provides high-quality prior information for subsequent adhesion coefficient evaluation and braking force distribution, which can synergistically shorten braking distance, reduce the risk of wheel locking, and improve vehicle directional stability and braking smoothness under multiple road conditions.

[0026] The present invention is further configured such that S5 includes: 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 adhesion mapping factor; Calculate the absolute difference between the normal load of the wheel at the current moment and the previous moment to obtain the load variation compensation factor; The wheel adhesion coefficient is calculated based on the wheel speed signal, instantaneous slip rate, and normal load, combined with the adhesion mapping factor and load variation compensation factor. Specifically, the adhesion mapping factor is calculated by the difference between the current instantaneous slip rate and the historical instantaneous slip rate. A difference measurement function is used to capture the dynamic characteristics of the slip rate over time. This method can effectively reflect the changing trend of the wheel-ground contact force. Especially when the slip rate changes significantly, the adhesion mapping factor can be adjusted in real time to optimize the wheel adhesion control. The calculation logic of the difference measurement function is as follows: , For the Wheels at the moment The adhesion mapping factor, by introducing the historical instantaneous slip rate difference, can more accurately capture the dynamic changes between the wheel and the road surface, thereby improving the stability of adhesion control; is the attenuation factor, which is used to adjust the influence of the slip rate difference on the current adhesion mapping factor, and its value range is [0,1]; is the time window size of the historical instantaneous slip rate, indicating how many historical moments of slip rate changes are considered; For the Wheels at the moment The instantaneous slip rate indicates the degree of slip between the wheel and the ground at the past moment; is a sensitivity parameter, used to adjust the speed of the slip ratio difference response to the adhesion mapping factor adjustment, with a value range of [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 time and the previous time, which is used to compensate the influence of wheel load change on adhesion, ensuring that the calculation of adhesion coefficient can be more accurate when the wheel load changes dramatically, and the calculation logic of the load variation compensation factor is: , 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, so as to ensure that the wheel adhesion force keeps pace with the actual load change and prevents the brake system from being unstable or over-responsive due to instantaneous load fluctuation; is the first normal load of the wheel at time ; is an adjustment coefficient, used to adjust the compensation degree of the influence of normal load change on adhesion coefficient, with a value range of [0.1, 1]; is a proportional factor, used to control the influence degree of normal load change on adhesion coefficient compensation, with a value range of [0.1, 1]; the adhesion coefficient is a key parameter to describe the friction between the wheel and the ground, which determines the friction between the tire and the ground, and is calculated by combining the slip ratio, wheel speed signal, normal load, adhesion mapping factor and load variation compensation factor, so as to ensure that the adhesion coefficient can accurately reflect the actual adhesion between the wheel and the ground under different working conditions, and the calculation logic of the adhesion coefficient is: , is the first adhesion coefficient of the wheel at time ; is the longitudinal speed of the vehicle at time ; is an adjustment coefficient, used to adjust the influence of instantaneous slip ratio on adhesion coefficient, with a value range of [0, 1]; the introduction of the above adhesion coefficient effectively reduces the adhesion force calculation error caused by the change of normal load, so as to ensure that the vehicle can maintain stable adhesion coefficient under different working conditions.

[0027] The application further provides that the S6 comprises: based on the absolute value of the deviation of the instantaneous slip ratio of each wheel from the preset target slip ratio, a slip sticking progress is generated through an exponential decay characteristic; the slip sticking progress and the hub response coupling factor are multiplied to generate the fusion weight of each wheel; The adhesion of the entire vehicle is calculated using the adhesion coefficient of each wheel as the base value and the corresponding fusion weight as the weighted value. Specifically, the slip progress is calculated based on the absolute value of the deviation between the instantaneous slip rate of the wheel and the preset target slip rate. The decreasing trend of the deviation is used to adjust the slip progress to ensure that the impact of the slip rate error on the adhesion ability is gradually reduced. The fusion weight is calculated by multiplying the slip progress by the wheel response coupling factor to generate a weighted weight for each wheel, thereby dynamically adjusting the influence of each wheel to ensure accurate calculation of the wheel adhesion ability. The calculation logic of the fusion weight is as follows: , For the Wheels at the moment The fusion weight of To track slip progress, the difference between the instantaneous slip rate and the preset target slip rate is calculated through exponential decay of the slip rate, ensuring that more attention is paid to wheels whose instantaneous slip rate is close to the target slip rate; is the attenuation factor, which is used to control the influence of slip rate deviation on fusion weight, and its value range is [0.1,5]. The adhesion capacity of the whole vehicle is determined by the adhesion coefficient of each wheel. and the corresponding fusion weights The calculation logic of the vehicle's adhesion capacity is obtained by weighted average: , For vehicles at time The vehicle's total adhesion capacity refers to the comprehensive adhesion capacity of all wheels of the vehicle, reflecting the sum of the traction (i.e. adhesion) generated by all wheels on the road in the current environment and state; is a parameter used to prevent the denominator from being zero, and its value range is [0.000001,0.001]; It is the weighted sum of the adhesion coefficients of each wheel, indicating the contribution of each wheel's adhesion to the overall wheel adhesion. It is the weighted sum of the influence weights of each wheel; by integrating the adhesion coefficient of each wheel, the influence of slip rate proximity and wheel hub response is comprehensively considered, and the adhesion ability of the entire vehicle can be effectively evaluated.

[0028] The present invention is further configured such that said S7 includes Calculate the control slip ratio reference value based on the difference between the vehicle's adhesion and the preset reference adhesion, combined with the preset target slip ratio; According to 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; Based on the difference between the maximum allowable braking force and the braking force at the previous moment, a braking force mutation suppression term with S-type saturation characteristics is constructed. The target braking force is obtained by nonlinearly combining the wheel adhesion coefficient, normal load, slip error influence term and braking force mutation suppression term. Specifically, the control slip rate reference value is determined by the adhesion capacity of the entire vehicle. The difference from the preset baseline adhesion and the preset target slip rate The calculation logic of the control slip ratio reference value is generated by combining: , For vehicles at time Control slip ratio reference value; is the preset benchmark adhesion capacity; and is the adjustment coefficient; Used to adjust the relationship between the vehicle's adhesion and the preset target slip rate, with a value range of [0.1, 1]; The response rate used to adjust the difference between adhesion and the preset target slip ratio is in the range of [0.1, 1]. The control slip ratio reference value calculation formula uses the difference between the total vehicle adhesion and the preset target adhesion, 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 the control slip ratio that matches the current road conditions and adhesion. The target braking force is calculated 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 takes into account the nonlinear attenuation of the slip ratio error and introduces a sigmoid-type suppression factor to prevent braking force mutations, thereby improving system stability and smoothness. The target braking force calculation logic is as follows: , For the Wheels at the moment The target braking force is used by the system to adjust the wheel braking effect; is the attenuation factor, which is used to adjust the influence of slip rate deviation on the target braking force, and its value range is [0,1]; is a nonlinear response factor used to adjust the nonlinear effect of slip ratio deviation on target braking force, with a value range of [0,1]; is a suppression factor used to avoid drastic fluctuations in braking force over time, with a value range of [0,5]; For the The maximum permissible braking force of the wheels; For the Wheels at the moment Target braking force; is the slip error influence term, which affects the distribution of the target braking force. The greater the difference between the control slip ratio reference value and the instantaneous slip ratio, the smaller the slip error influence term, and thus the contribution to the target braking force is reduced; For the brake force mutation inhibition term, for preventing sudden change of brake force caused by instantaneous change of slip ratio or other factors, through the smoothing property of Sigmoid function, the brake force is smoothly transitioned between different time points, effectively avoiding excessive or unstable braking response; through the above calculation, the system realizes precise control of the wheel brake force, optimizes the balance between the slip ratio and the brake force, so that the ABS system can dynamically adjust the target brake force distribution according to different road conditions and changes of adhesion, and adjust the brake intensity of each wheel according to the target brake force.

[0029] The application is further provided that, based on the deviation between the control slip ratio reference value and the instantaneous slip ratio of each wheel, the adhesion coefficient of each wheel and the hub response coupling factor are combined to calculate a slip ratio error accumulation index; 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; Based on the difference between the slip ratio error accumulation index and the preset error threshold, the updated control slip ratio reference value is calculated in combination with the control slip ratio reference value at the previous moment; specifically, the slip ratio error accumulation index is used to measure the overall error of the system in the control slip ratio process, and the deviation between the control slip ratio reference value and the instantaneous slip ratio of each wheel is comprehensively considered in combination with the adhesion coefficient of the wheel and the hub response coupling factor, and the calculation logic of the slip ratio error accumulation index is: , The slip ratio error accumulation index is used to measure the overall error in the slip ratio deviation, and to avoid adjustment based on only the slip ratio error at a single moment; represents all moments from time to time , that is, all moments within a preset time window , is the time; is the control slip ratio reference value of the vehicle at time ; the wheel at time ; is the adhesion coefficient of the wheel at time ; is the hub response coupling factor of the wheel at time ; is an exponential coefficient, used to control the influence degree of the slip ratio deviation on the slip ratio error accumulation index, and the value range is [0.5, 5]; is an adjustment coefficient for controlling the influence degree of the adhesion coefficient and the hub response coupling factor in the error accumulation process, and the value range is [0.1, 1]; the outer summation in the above slip ratio error accumulation index calculation logic represents the accumulation of the error at each time in a time window, and the inner summation represents the summation of the error of each wheel, so as to ensure that the slip ratio error of the whole vehicle is comprehensively considered; when the slip ratio error accumulation index is greater than a preset error threshold value, it indicates that the control accuracy of the ABS system is reduced, and the control slip ratio needs to be adjusted, and the adaptive updating mechanism of the control slip ratio reference value is started, and the control slip ratio reference value is updated to realize accurate adjustment and improve the control effect; the updating logic of the control slip ratio reference value is as follows: , , is the updated control slip ratio reference value of the vehicle at time ; is the control slip ratio reference value of the vehicle at the previous time ; and is an adjustment coefficient; is a preset error threshold value; is used for controlling the amplitude of each control slip ratio reference value adjustment, and the value range is [0.01, 1]; is used for adjusting the response sensitivity of the system to the slip ratio error, and the value range is [0, 5]; the adaptive adjustment can respond to the change of the slip ratio error in real time, and ensure that the system can run quickly and stably under various working conditions.

[0030] The application further sets that the target braking force is dynamically adjusted according to the updated control slip ratio reference value; specifically, when the control slip ratio reference value is updated, the new control slip ratio reference value will directly affect the calculation of the target braking force, the updated control slip ratio reference value is taken as the input, and the target braking force is adjusted to ensure that the system can guarantee the stability of the vehicle while optimizing the braking force distribution, so as to realize more accurate and efficient braking effect; the dynamic adjustment mechanism can respond to various driving conditions in real time, especially when the slip ratio changes greatly, the control slip ratio reference value is adjusted to reduce the slip ratio error and avoid large deviation, so as to improve the braking performance and enhance the safety of the system; in addition, the system can intelligently adapt to different road conditions, speed changes and other dynamic factors, so as to ensure that the wheels are always maintained in the range close to the optimal slip ratio, thereby providing more stable and safe driving experience.

[0031] ​​​​​​In the present application, the system realizes the optimization of vehicle braking performance by collecting multi-source sensor data of the wheels and dynamically adjusting the target braking force combined with the control algorithm; the system synchronously collects multi-source hub sensor signals of each wheel, and the data of each wheel includes wheel speed signal, radial acceleration signal, tangential acceleration signal and braking torque signal; by real-time calculation of the whole vehicle adhesion capacity and target braking force corresponding to each time k, the braking effect is optimized; for example, at time k=1, the system collects the wheel speed signal of the 1st wheel as 15.3 m / s, the radial acceleration signal as 2.6 m / s², the tangential acceleration signal as 2.0 m / s², and the braking torque as 260 Nm; the wheel speed signal of the 2nd 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 whole vehicle adhesion capacity is 0.87, the system calculates that the target braking force of the 1st wheel is 125 N, and the target braking force of the 2nd wheel is 123 N; at time k=2, the system collects the wheel speed signal of the 1st 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 2nd wheel is 14.8 m / s, 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, at this time, the whole vehicle adhesion capacity is 0.85, the target braking force of the 1st wheel is adjusted to 120 N, and the target braking force of the 2nd wheel is adjusted to 118 N; according to the real-time wheel state data and the calculated whole vehicle adhesion capacity and target braking force, the system can dynamically adjust the braking force output to ensure that the vehicle maintains the best braking performance under different road conditions; when the whole vehicle adhesion capacity is high, such as at time k=1, the system sets the target braking force of the 1st wheel and the 2nd wheel to 125 N and 123 N respectively, and when the whole vehicle adhesion capacity is low, such as at time k=2, the system reduces the target braking force of the 1st wheel and the 2nd wheel to 120 N and 118 N respectively, thereby avoiding wheel slip or loss of control; through this dynamic adjustment mechanism, the vehicle can optimize the braking effect according to different braking requirements, real-time monitor and control the sensor data of each wheel, so that the braking force can be accurately adjusted, thereby maintaining the best adhesion and braking performance under various road conditions; the control system not only improves the safety and stability of the vehicle, especially under wet or complex road conditions, but also prevents the situation of wheel lock or low adhesion, ensuring the efficiency and accuracy of braking response.

[0032] Example Two For reference Figure 2 The example ABS real-time adaptive control system based on hub sensor signal fusion includes: The data acquisition module is configured to synchronously acquire multi-source hub sensor signals of each wheel, wherein the multi-source hub sensor signals comprise wheel speed signals, radial acceleration signals, tangential acceleration signals and brake torque signals. The hub response calculation module is configured to calculate hub response coupling factors of the wheels based on dynamic response characteristics of the multi-source hub sensor signals. The instantaneous slip ratio calculation module is configured to calculate instantaneous slip ratios of the wheels based on the hub response coupling factors and the wheel speed signals, in combination with a vehicle longitudinal speed and a tire rolling radius. The normal load calculation module is configured to calculate normal loads of the wheels based on the wheel speed signals, the brake torque signals and the tangential acceleration signals, in combination with the hub response coupling factors and the instantaneous slip ratios. The adhesion coefficient calculation module is configured to calculate adhesion coefficients of the wheels according to the instantaneous slip ratios, the normal loads and the wheel speed signals. The adhesion capacity calculation module is configured to calculate a total vehicle adhesion capacity according to deviations of the instantaneous slip ratios of the wheels from a preset target slip ratio, in combination with the hub response coupling factors. The target brake force calculation module is configured to calculate target brake forces according to the adhesion coefficients, the normal loads, the instantaneous slip ratios of the wheels and the total vehicle adhesion capacity, and to adjust brake intensities of the wheels according to the target brake forces.

[0033] It should be noted that the ABS real-time self-adaptive control system based on hub sensor signal fusion provided in the above embodiments and the ABS real-time self-adaptive control method based on hub sensor signal fusion provided in the above embodiments belong to the same concept, wherein the specific manner in which each module and unit performs operations has been described in detail in the method embodiments, which will not be repeated here. In actual application, the above functions can be completed by different functional modules according to needs, i.e., the internal structure of the system is divided into different functional modules to complete all or part of the functions described above, and this is not limited herein.

[0034] The above merely provides a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be encompassed in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. ABS real-time adaptive control method based on wheel hub sensor signal fusion, characterized in that: include: S1: synchronously collecting multi-source hub sensor signals of each wheel, wherein the multi-source hub sensor signals include wheel speed signal, radial acceleration signal, tangential acceleration signal and braking torque signal; S2: Calculate the wheel hub response coupling factor based on the multi-source wheel hub sensor signals; S3: Calculates the instantaneous wheel slip rate based on the hub response coupling factor and wheel speed signal, combined with the vehicle longitudinal speed and tire rolling radius; S4: Calculate the normal load of the wheel based on the wheel speed signal, braking torque signal and tangential acceleration signal, combined with the hub response coupling factor and instantaneous slip rate; S5: Calculate the wheel adhesion coefficient based on the instantaneous slip rate, normal load and wheel speed signal; S6: 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, a fusion weight is generated to calculate the adhesion of the entire vehicle; S7: Calculate the target braking force based on the adhesion coefficient, normal load, instantaneous slip rate and overall vehicle adhesion of each wheel, and adjust the braking intensity of each wheel based on the target braking force.

2. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 1 is characterized in that: The S2 includes: The wheel speed signal, radial acceleration signal, tangential acceleration signal and braking torque signal of each wheel hub position are synchronously collected through sensors; Based on the time series difference calculation of the wheel speed signal, the acceleration characteristics of the dynamic change of the wheel speed are extracted; Calculate the radial vibration intensity characteristics of the hub based on the differential accumulation of the radial acceleration signal; Generate torque and acceleration coupling characteristics according to the absolute value of the product of the tangential acceleration signal and the braking torque signal; The acceleration characteristics, vibration intensity characteristics and coupling characteristics are integrated to calculate the hub response coupling factor.

3. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 1 is characterized in that: The S3 includes: The collected wheel speed signal is dynamically corrected using the hub response coupling factor; The corrected wheel speed signal is mapped to the vehicle longitudinal speed and tire rolling radius through a nonlinear function to calculate the instantaneous slip rate of each wheel.

4. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 1, characterized in that: The S4 includes: The braking 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 weightedly superimposed to generate a composite basic load term; The time-varying compression index is calculated by combining the wheel speed signal difference value, the braking torque signal difference value and the instantaneous slip ratio difference value; The normal load on the wheel is calculated based on the composite base load term and the time-varying compression index.

5. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 1 is characterized in that: The S5 includes: 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 adhesion mapping factor; Calculate the absolute difference between the normal load of the wheel at the current moment and the previous moment to obtain the load variation compensation factor; The wheel adhesion coefficient is calculated based on the wheel speed signal, instantaneous slip rate and normal load, combined with the adhesion mapping factor and load variation compensation factor.

6. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 1 is characterized in that: The S6 includes: Based on the absolute value of the deviation between the instantaneous slip rate of each wheel and the preset target slip rate, the slip progress is generated through the exponential decay characteristic; Multiply the slippage progress and the wheel response coupling factor to generate the fusion weight of each wheel; The adhesion coefficient of each wheel is used as the base value and combined with the corresponding fusion weight to calculate the adhesion capacity of the entire vehicle.

7. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 1 is characterized in that: The S7 includes Calculate the control slip ratio reference value based on the difference between the vehicle's adhesion and the preset reference adhesion, combined with the preset target slip ratio; According to 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; Based on the difference between the maximum allowable braking force and the braking force at the previous moment, a braking force mutation suppression term with S-type saturation characteristics is constructed. The target braking force is obtained by nonlinearly combining the wheel adhesion coefficient, normal load, slip error influence term and braking force mutation suppression term.

8. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 7 is characterized in that: Based on the deviation between the control slip ratio reference value and the instantaneous slip ratio of each wheel, combined with the adhesion coefficient and hub response coupling factor of each wheel, the slip ratio error accumulation index is calculated; When the slip ratio error accumulation index is greater than a preset error threshold, an adaptive update of the control slip ratio reference value is initiated; An updated control slip ratio reference value is calculated based on a difference between the slip ratio error accumulation index and a preset error threshold value and a control slip ratio reference value at a previous moment.

9. The ABS real-time adaptive control method based on wheel hub sensor signal fusion according to claim 8, characterized in that: The target braking force is dynamically adjusted according to the updated control slip ratio reference value.

10. An ABS real-time adaptive control system based on wheel hub sensor signal fusion, used to implement the ABS real-time adaptive control method based on wheel hub sensor signal fusion according to any one of claims 1 to 9, characterized in that: include: Data acquisition module: used to synchronously collect multi-source hub sensor signals of each wheel, wherein the multi-source hub sensor signals include wheel speed signal, radial acceleration signal, tangential acceleration signal and braking torque signal; 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 sensor signals; Instantaneous slip calculation module: used to calculate the instantaneous slip rate of the wheel based on the hub response coupling factor and wheel speed signal, combined with the vehicle longitudinal speed and tire rolling radius; Normal load calculation module: used to calculate the normal load of the wheel based on the wheel speed signal, braking torque signal and tangential acceleration signal, combined with the hub response coupling factor and instantaneous slip rate; Adhesion coefficient calculation module: used to calculate the adhesion coefficient of the wheel based on the instantaneous slip rate, normal load and wheel speed signal; Adhesion calculation module: This module calculates the adhesion of the entire vehicle 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, to generate a fusion weight. Target braking force calculation module: used to calculate the target braking force based on the adhesion coefficient, normal load, instantaneous slip rate and adhesion capacity of each wheel, and adjust the braking intensity of each wheel according to the target braking force.

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