Vehicle braking vibration reduction method, device and equipment and storage medium

Abstract

The invention relates to the technical field of vehicle control, and discloses a vehicle braking vibration reduction method, device and equipment and a storage medium, and the method comprises the steps that when an approaching obstacle is detected, available braking related signals are determined; determining a target damping coefficient according to the vehicle speed information based on the brake-related signal; and controlling an electric control shock absorber in the vehicle based on the target damping coefficient. When it is detected that the vehicle is close to the obstacle and possibly brakes, the corresponding target damping coefficient can be calculated and determined according to the obtained brake related signal, and the electric control shock absorber in the vehicle is controlled according to the target damping coefficient to generate the corresponding damping force before real braking; therefore, the pitching condition of the vehicle caused by follow-up braking is counteracted or weakened, and the actual driving experience is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a vehicle braking and vibration reduction method, device, equipment and storage medium. Background Art

[0002] The current electronically controlled shock absorbers will only be activated after detecting changes in the vehicle's longitudinal acceleration, the brake pedal travel sensor in the vehicle detecting that the brake pedal is depressed, the ABS (Anti-lock Braking System) signal from the autonomous driving controller is sent, or changes in the brake cylinder hydraulic pressure are detected to offset or reduce the vehicle's pitch phenomenon during braking. However, the current adjustment process has a lag, and the braking action has actually occurred at this time, and the vehicle has already experienced pitching, resulting in a poor actual vehicle driving experience. Summary of the invention

[0003] The main purpose of the present application is to provide a vehicle braking vibration reduction method, device, equipment and storage medium, aiming to solve the technical problem of the control and adjustment of the electronically controlled shock absorber in the related technology to offset the lag of the pitch phenomenon of the vehicle during braking.

[0004] To achieve the above objectives, the present application proposes a vehicle braking vibration reduction method, the method comprising:

[0005] determining available brake-related signals when an approaching obstacle is detected;

[0006] Based on the brake-related signal, determining a target damping coefficient according to vehicle speed information;

[0007] An electronically controlled shock absorber in the vehicle is controlled based on the target damping coefficient.

[0008] Optionally, determining a target damping coefficient based on the brake-related signal and according to vehicle speed information includes:

[0009] detecting whether the braking-related signal includes a road surface recognition signal;

[0010] If the brake-related signal includes a road surface recognition signal, generating a simulated nodding force according to vehicle speed information;

[0011] Substituting the simulated nodding force into the four-degree-of-freedom half-car model for calculation, and generating a pitch angle vector;

[0012] Determining a pitch control torque according to the pitch angle vector;

[0013] A target damping coefficient is generated according to the pitch control moment.

[0014] Optionally, after detecting whether the braking-related signal includes a road surface recognition signal, the method further includes:

[0015] If the brake-related signal does not include a road surface recognition signal, extracting the current vehicle speed from the vehicle speed information;

[0016] If the current vehicle speed is less than a preset vehicle speed threshold, obtaining a speed difference between the current vehicle speed and the preset vehicle speed threshold;

[0017] determining a correction factor according to the speed difference;

[0018] The target damping coefficient is determined according to the correction coefficient and a maximum damping coefficient, wherein the maximum damping coefficient is a maximum value of the damping coefficient supported by the electronically controlled shock absorber in the vehicle.

[0019] Optionally, determining the pitch control torque according to the pitch angle vector includes:

[0020] Get the pitch control type of the vehicle;

[0021] Determining a torque determination method according to the pitch control type;

[0022] The pitch control torque is determined according to the torque determination method and the pitch angle vector.

[0023] Optionally, generating a target damping coefficient according to the pitch control moment includes:

[0024] Get the vehicle suspension category of the vehicle;

[0025] Obtaining a damping force generation method corresponding to the vehicle suspension type;

[0026] According to the damping force generation method, a target damping coefficient is determined according to the pitch control moment.

[0027] Optionally, before determining the simulated nodding force of the vehicle according to the speed information of the vehicle when an adjacent obstacle is detected, the method further includes:

[0028] When an obstacle is detected by road recognition signals but no braking signal of the autonomous driving function is detected, the obstacle contact time is determined based on the vehicle speed information, and when the obstacle contact time is less than a preset time threshold, it is determined that an adjacent obstacle is detected;

[0029] or,

[0030] When an obstacle is detected by road recognition signals but no hydraulic pressure change in the brake cylinder of the brake system is detected, the obstacle contact time is determined based on the vehicle speed information, and when the obstacle contact time is less than a preset time threshold, it is determined that an adjacent obstacle is detected;

[0031] or,

[0032] When a brake hydraulic pre-fill signal of the autonomous driving function is detected but an emergency braking signal of the autonomous driving function is not detected, it is determined that an adjacent obstacle is detected.

[0033] Optionally, after controlling the electronically controlled shock absorber in the vehicle based on the target damping coefficient, the method further includes:

[0034] When an emergency braking signal of the autonomous driving function is detected, extracting a target deceleration from the emergency braking signal;

[0035] determining a target nodding force according to the target deceleration;

[0036] A new target damping coefficient is generated according to the target nodding force, and the process returns to the step of controlling the electronically controlled shock absorber in the vehicle based on the target damping coefficient.

[0037] In addition, to achieve the above-mentioned purpose, the present application also proposes a vehicle braking and vibration reduction device, the device comprising:

[0038] A detection module, for determining an obtainable braking-related signal when an approaching obstacle is detected;

[0039] A determination module, configured to determine a target damping coefficient based on the braking-related signal and vehicle speed information;

[0040] A control module is used to control an electronically controlled shock absorber in a vehicle based on the target damping coefficient.

[0041] In addition, to achieve the above-mentioned purpose, the present application also proposes a vehicle braking and vibration reduction device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the vehicle braking and vibration reduction method as described above.

[0042] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the vehicle braking vibration reduction method as described above are implemented.

[0043] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the vehicle braking vibration reduction method described above are implemented.

[0044] One or more technical solutions proposed in this application have at least the following technical effects:

[0045] Since it is possible to detect that the vehicle is approaching an obstacle and braking may occur, the corresponding target damping coefficient can be determined based on the available braking-related signals, and the electronically controlled shock absorber in the vehicle can be controlled according to the target damping coefficient before actual braking to generate corresponding damping force to offset or weaken the vehicle pitch caused by subsequent braking, thereby improving the actual driving experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0047] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0048] Figure 1 A schematic diagram of a process flow provided for the first embodiment of the vehicle braking and vibration reduction method of the present application;

[0049] Figure 2 A schematic diagram of a flow chart provided for the second embodiment of the vehicle braking and vibration reduction method of the present application;

[0050] Figure 3 This is a schematic diagram of a four-degree-of-freedom half-car model according to an embodiment of the present application;

[0051] Figure 4 This is a schematic diagram of the operation flow of solving a four-degree-of-freedom half-car model according to an embodiment of the present application;

[0052] Figure 5 This is a schematic diagram of the module structure of the vehicle braking and vibration reduction device according to an embodiment of the present application;

[0053] Figure 6 Schematic diagram of the device structure of the hardware operating environment involved in the vehicle braking vibration reduction method in the embodiment of the present application.

[0054] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0055] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0056] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0057] Based on this, the embodiment of the present application provides a vehicle braking vibration reduction method, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the vehicle braking and vibration reduction method of the present application.

[0058] In this embodiment, the vehicle braking and vibration reduction method includes steps S10 to S30:

[0059] Step S10: When an approaching obstacle is detected, determining an obtainable braking-related signal.

[0060] It should be noted that the executor of this embodiment can be the vehicle itself or a vehicle braking and vibration reduction device arranged in the vehicle. The vehicle braking and vibration reduction device can be a controller arranged in the vehicle, such as an ECU controller, or other devices that can achieve the same or similar functions. This embodiment is not limited to this. In this embodiment and the following embodiments, the vehicle braking and vibration reduction method of the present invention is explained by taking the vehicle braking and vibration reduction device as an example.

[0061] It should be noted that in order to ensure that the vehicle does not pitch as much as possible, the electronically controlled shock absorber needs to be reasonably controlled before the vehicle actually brakes. Therefore, during the driving process of the vehicle, if it is close to an obstacle, the vehicle will most likely brake to avoid the obstacle in order to facilitate vehicle adjustment. Due to safety considerations or authority settings, the vehicle's braking and shock absorbing equipment may not be able to obtain signals from all functions in the vehicle. At this time, in order to reasonably control the electronically controlled shock absorber, the braking-related signals that can be obtained by the vehicle's braking and shock absorbing equipment can be determined first to determine how to calculate the correlation coefficient used for control.

[0062] The braking-related signal may be a signal sent by a function related to braking vibration reduction that can be obtained by the vehicle braking vibration reduction device during the vehicle braking vibration reduction control process. In this embodiment, since obstacles can be determined by performing image acquisition and image recognition on the road surface during the judgment (such as using a front camera to acquire road surface information in front, identifying the road surface information in front, and determining the elevation information of the road surface in front), the braking-related signal may include a road surface recognition signal;

[0063] At the same time, the vehicle may use automatic driving, assisted driving and other functions. At this time, the automatic driving function is actually related to braking vibration reduction. Therefore, the braking-related signal may also include the automatic driving function.

[0064] In actual use, when different brake-related signals are available, different information can be obtained. Naturally, when the vehicle is braked and damped, the calculation method used will also be different. Therefore, the available brake-related signals can be determined first.

[0065] In a specific implementation, in order to accurately determine whether an obstacle is near, before step S10 in this embodiment, the following may also be included:

[0066] When an obstacle is detected by road recognition signals but no braking signal of the autonomous driving function is detected, the obstacle contact time is determined based on the vehicle speed information, and when the obstacle contact time is less than a preset time threshold, it is determined that an adjacent obstacle is detected;

[0067] or,

[0068] When it is determined that an obstacle is detected through the road recognition signal, but no change in the brake cylinder hydraulic pressure in the brake system is detected, the obstacle contact time is determined based on the vehicle speed information, and when the obstacle contact time is less than a preset time threshold, it is determined that an adjacent obstacle is detected;

[0069] or,

[0070] When a brake hydraulic pre-fill signal of the autonomous driving function is detected but an emergency braking signal of the autonomous driving function is not detected, it is determined that an adjacent obstacle is detected.

[0071] It should be noted that when the available brake-related signals are different, the way to determine whether an obstacle is approaching will also be different. The obstacle contact time can be the interval time between the vehicle maintaining the current speed and contacting the obstacle. The obstacle can be an obstacle on the road, such as a pedestrian, a triangular cone, etc., or an obstacle that may move.

[0072] In actual use, if the obtainable braking-related signals include road surface recognition signals and autonomous driving signals, and at this time, it can be determined that an obstacle is detected through the road surface recognition signal, but the braking signal of the autonomous driving function is not detected, it can be determined that although the obstacle is detected at this time, the obstacle is still far away from the vehicle. At this time, the obstacle contact time can be determined based on the vehicle speed information;

[0073] If the obstacle contact time is less than the preset time threshold, it means that if the vehicle continues to move, it may come into contact with the obstacle in a shorter time. At this time, the vehicle is more likely to brake. Therefore, it can be determined that an adjacent obstacle is detected.

[0074] Among them, the preset time threshold can be calibrated in advance by the manager of the vehicle's braking and shock absorption equipment; the automatic driving signal may include various signals sent by the automatic driving function, and the braking signal of the automatic driving function may include a pre-processing signal and an emergency braking signal. The pre-processing signal is a pre-filled signal issued in advance before the automatic driving function controls the vehicle's emergency braking, such as a PrefillRequest signal.

[0075] For example: based on the available signals, if it is determined that the front camera of the vehicle detects an obstacle ahead (such as a vehicle, pedestrian, etc.), and at the same time does not detect the PrefillRequest signal and the emergency braking signal issued by the autonomous driving domain controller (such as the Automated Driving Control Unit, AD domain controller, or ADCU), then the relative distance l between the vehicle and the obstacle is identified based on the image captured by the front camera, and the estimated contact time t=l / v is calculated based on the current vehicle speed v. If t is less than the preset time threshold t_set, it is determined that an adjacent obstacle is detected, and step S10 is started.

[0076] In actual use, if only the road recognition signal can be obtained but the automatic driving signal cannot be obtained, then at this time, it is possible to determine whether the vehicle has emergency braked to avoid the obstacle by detecting the changes in the brake hydraulic cylinder. Therefore, if an obstacle is detected through the road recognition signal, but no changes in the brake hydraulic cylinder in the vehicle's braking system are detected, it can also be determined that the vehicle is far away from the obstacle. The obstacle contact time can also be determined based on the vehicle speed information. If the obstacle contact time is less than the preset time threshold, it means that if the vehicle continues to drive at this time, it may come into contact with the obstacle in a shorter time. At this time, the vehicle is more likely to brake. Therefore, it can be determined that an adjacent obstacle is detected.

[0077] If a change in the state of the brake hydraulic cylinder is detected, it can be determined that the vehicle is already performing an emergency braking action. At this time, no subsequent judgment is required, but the maximum damping coefficient is directly used as the target damping coefficient, and step S30 is executed.

[0078] In actual use, if only the automatic driving signal can be obtained but the road recognition signal cannot be obtained, then at this time, only the relevant signals of the automatic driving function can be used to determine whether there is an approaching obstacle. If the brake hydraulic pre-fill signal of the automatic driving function is detected but the emergency braking signal of the automatic driving function is not detected, it means that the vehicle is already close to the obstacle but there is still a certain distance, and the vehicle does not directly perform emergency braking. Therefore, it can be determined that an approaching obstacle is detected.

[0079] Step S20: Based on the brake-related signal, determine a target damping coefficient according to vehicle speed information.

[0080] In actual use, after determining the obtainable braking-related signals, the currently available information can be determined, such as road elevation information, related control signals, etc. Based on the available information, the available calculation method for calculating the related control coefficients can be determined. Then, based on the calculation method and combined with the vehicle speed information, calculations can be performed to determine the target damping coefficient.

[0081] Step S30: Controlling the electronically controlled shock absorber in the vehicle based on the target damping coefficient.

[0082] In actual use, an electronically controlled shock absorber can be installed in the vehicle. The damping force during vibration reduction can be adjusted by adjusting the parameters of the electronically controlled shock absorber. At this time, the electronically controlled shock absorber in the vehicle can be controlled and adjusted so that the damping force output by the electronically controlled shock absorber is the damping force corresponding to the target damping coefficient. The damping force output by the electronically controlled shock absorber can offset the pitching of the vehicle as much as possible.

[0083] Specifically, the current value corresponding to the target damping coefficient may be output to the solenoid valve of the electronically controlled shock absorber through the electronically controlled shock absorber controller, thereby generating a damping force corresponding to the target damping coefficient.

[0084] Of course, it can also be directly output to the active suspension system in the vehicle, allowing it to generate corresponding active force to offset the pitch of the vehicle.

[0085] In actual application, the damping coefficient that the electronically controlled shock absorber can produce actually has an upper limit, that is, the damping force that the electronically controlled shock absorber can produce has an upper limit. In order to ensure that the electronically controlled shock absorber can be reasonably controlled, after obtaining the target damping coefficient, the target damping coefficient can also be compared with the maximum damping coefficient supported by the electronically controlled shock absorber, and the electronically controlled shock absorber can be controlled according to the smaller value to avoid the damping coefficient exceeding the upper limit supported by the electronically controlled shock absorber.

[0086] The present embodiment provides a vehicle braking vibration reduction method. When it is detected that the vehicle is approaching an obstacle and braking may occur, the corresponding target damping coefficient can be determined based on the obtainable braking-related signals, and the electronically controlled shock absorber in the vehicle can be controlled according to the target damping coefficient before actual braking to generate a corresponding damping force to offset or weaken the vehicle pitch caused by subsequent braking, thereby improving the actual driving experience.

[0087] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can refer to the above introduction, and will not be repeated later. Figure 2 , step S20 includes steps S201 to S05:

[0088] Step S201: Detect whether the braking-related signal includes a road surface recognition signal.

[0089] Step S202: If the braking-related signal includes a road surface recognition signal, a simulated nodding force is generated according to the vehicle speed information.

[0090] Step S203: Substitute the simulated nodding force into the four-degree-of-freedom half-car model for calculation to generate a pitch angle vector.

[0091] It should be noted that if the obtainable braking-related signals include road surface recognition signals, it means that the vehicle braking and vibration reduction equipment can obtain road surface data fed back by cameras or other similar image acquisition devices. At this time, the road surface information ahead can be determined based on the road surface recognition signals, and the road surface elevation information ahead can be obtained. At the same time, the displacement of each wheel in the vehicle and other information can also be inferred. At this time, the pitch angle vector required for control can be inferred based on the pre-set four-degree-of-freedom half-car model. Among them, the pitch angle vector can include the pitch angle, pitch angle velocity and pitch angle acceleration required to achieve the pitch control torque.

[0092] Therefore, it is possible to first detect whether the obtainable braking-related signal includes a road surface recognition signal, and if so, then a simulated nodding force can be generated first according to the vehicle speed information, wherein the vehicle speed information may include information such as the current vehicle speed and the current vehicle acceleration.

[0093] For example, to calculate the simulated deceleration, the simulated deceleration assumes that the speed is just reduced to 0 at the time of contact, then the following formula exists: v-at = 0; at this time, the simulated braking force F = ma, and the simulated nodding force F dive =F / (H*L). If the simulated nodding force is decomposed, then the simulated nodding force of the front wheel of the vehicle at this time is f f,dive =F dive , the simulated nodding force of the rear wheel f r,dive =-F dive , where v is the current speed of the vehicle, t is the time it takes for the vehicle to touch the obstacle at the current speed, H is the height of the vehicle's center of mass, and L is the wheelbase of the front and rear wheels of the vehicle.

[0094] Step S204: determining the pitch control torque according to the pitch angle vector.

[0095] It should be noted that the pitch control torque may be the torque that needs to be provided by some components of the vehicle that resist pitching in order to offset the simulated pitching force.

[0096] In actual use, the manager of the vehicle braking and shock absorbing equipment can perform calibration in advance, set different control torques according to the direction and magnitude of the pitch force, and store the calibration results in a pitch torque mapping table. At this time, determining the pitch control torque based on the simulated pitch force can be done by searching the pitch control torque corresponding to the simulated roll force in the pitch torque mapping table.

[0097] Among them, since the calibration requires a lot of manpower, it may not be possible to calibrate too many values. In this case, a small number of pitch force intervals can be calibrated, and the corresponding pitch moment can be set for the pitch force interval. At this time, the corresponding pitch force interval can be determined according to the simulated pitch force, and then the pitch moment corresponding to the pitch force interval can be used as the pitch control moment.

[0098] In a specific implementation, due to the calibration method, there may be certain errors. To avoid this situation, the pitch control torque may be calculated in real time. In this case, step S204 in this embodiment may include:

[0099] Get the pitch control type of the vehicle;

[0100] Determining a torque determination method according to the pitch control type;

[0101] The pitch control torque is determined according to the torque determination method and the pitch angle vector.

[0102] It should be noted that the roll control type may be a control method of the vehicle when performing corresponding pitch moment control, and may include PID control, sky-hook control, and the like.

[0103] In actual use, different control types require different parameters when generating the roll control torque, and the calculation method of the roll control torque is also different. In order to reasonably determine the target roll moment, the roll control type of the vehicle can be obtained first, and the torque determination method can be determined according to the roll control type. Finally, the target roll moment is determined according to the torque determination method and the tilt angle vector.

[0104] For example: Assume that the pitch angle vector Where θ is the pitch angle, is the pitch angular velocity, is the pitch angular acceleration, T is the matrix transpose symbol;

[0105] At this time, if PID control is used in the vehicle, the roll control torque can be defined as:

[0106] Among them, K P , K I , K D is the PID control coefficient;

[0107] If a ceiling-like control is used, Roll-hook control can be defined. In this case, the roll control torque can be defined as Among them, K is the Roll-hook coefficient.

[0108] Step S205: generating a target damping coefficient according to the pitch control torque.

[0109] In actual use, the management personnel of the vehicle braking and shock absorbing equipment can pre-calibrate the correspondence between the pitch control torque and the damping coefficient, and construct a torque coefficient mapping table based on the calibration results. At this time, the corresponding damping coefficient can be found in the torque coefficient mapping table according to the pitch control torque, and the found damping coefficient can be used as the target damping coefficient.

[0110] Similarly, since calibration requires a lot of manpower, when constructing the moment coefficient mapping table, multiple intervals can also be set for calibration. The implementation method is similar to the above-mentioned pitch force interval method and will not be repeated here.

[0111] In a specific implementation, due to the calibration method, there may be certain errors. To avoid this situation, the target damping coefficient may be calculated in real time. In this case, step S205 in this embodiment may include:

[0112] Get the vehicle suspension category of the vehicle;

[0113] Obtaining a damping force generation method corresponding to the vehicle suspension type;

[0114] According to the damping force generation method, a target damping coefficient is determined according to the pitch control moment.

[0115] It should be noted that, according to different control modes, vehicle suspension can be divided into two categories: active suspension and semi-active suspension. Of course, more categories can be divided according to actual needs, and this embodiment does not limit this. The manager of the vehicle braking and vibration reduction equipment can set different damping force generation modes for different types of vehicle suspensions in advance.

[0116] In actual use, the target damping coefficient can be calculated according to the pitch control torque in different ways according to the damping force generation method.

[0117] For example, if the vehicle suspension type is active suspension, then the front suspension active force f can be defined as f =M / (l f +l r ), the main force of the rear suspension f r =-M / (l f +l r ), where l f and l r is the distance from the center of the front and rear axles to the center of mass, and M is the pitch control moment;

[0118] If the vehicle suspension type is semi-active suspension, then because the electronically controlled shock absorber in this type of suspension does not produce a negative damping coefficient, the damping force f of the front suspension can be defined as f =M / l f, the rear suspension does not generate additional damping force, and then the suspension displacement output by the height sensor can be differentiated to obtain the suspension relative speed, and the damping force can be divided by the suspension relative speed to obtain the target damping coefficient c.

[0119] In actual use, the generated active force or damping force can also be added to the external force input vector U, and then input into the four-degree-of-freedom half-car model for calculation, so as to obtain the pitch angle vector and the corresponding pitch control torque at subsequent moments in turn.

[0120] For ease of understanding, now combined Figure 3 and 4 This is for illustration but not for limitation. Figure 3 is a schematic diagram of a four-degree-of-freedom half-car model of this embodiment, Figure 4 This is a schematic diagram of the solution operation flow of the four-degree-of-freedom half-car model of this embodiment.

[0121] The four-degree-of-freedom half-car model can be Figure 3 As shown, the system state equation in this model can be characterized as:

[0122]

[0123] The state equation includes:

[0124] State parameter vector:

[0125] Pitch angle vector:

[0126] External force input vector: U = (f f +f f，dive f r +f r，dive ) T ;

[0127] Road surface input vector: W = (z tl z tr ) T ;

[0128] A, B, C, F, and D are all matrix parameters:

[0129]

[0130]

[0131] In the above formula, Z S is the vertical displacement at the center of mass, Z ul and Z ur is the vertical displacement of the front and rear axles in the unsprung position, Z tl and Z tris the displacement of the front and rear axles at the tire contact point, θ is the pitch angle of the vehicle body; m S is the sprung mass, m ul and m ur is the unsprung mass of the front and rear axles; k sf and k sr is the suspension spring stiffness of the front and rear axles; c sf and c sr is the damping coefficient of the current shock absorber output of the front and rear axles (or the damping coefficient of the passive shock absorber); l f and l r is the distance from the center of the front and rear axles to the center of mass, l f +l r =L, L is the distance between the front axle and the rear axle in the vehicle; I y is the moment of inertia.

[0132] And as Figure 4 As shown in FIG. 1 , the elevation information of the road ahead detected by the front camera of the vehicle can be used as the road input vector W, and the simulated nodding force can be calculated according to the vehicle speed information, which can be used as the external force input matrix U. Then, W, U, and A can be input as control vectors into the four-degree-of-freedom half-car model for calculation to obtain the output vector Y (i.e., the pitch angle vector), and the pitch angle θ and the pitch angle velocity can be extracted from Y. and pitch angular acceleration After that, the pitch control moment M can be calculated based on the vector Y, and it can be decomposed to determine the front and rear pitch control forces f f and f r , finally, determine the target damping coefficient c.

[0133] In a specific implementation, if the obtainable braking-related signal does not include a road surface recognition signal, then the vehicle braking and vibration reduction device cannot obtain road surface information at this time. Since the road surface input vector changes greatly during initial braking, it is difficult to calculate based on the previous road surface information. Therefore, it is necessary to use other methods to calculate the target damping coefficient. At this time, after step S201 described in this embodiment, the following may also be included:

[0134] If the brake-related signal does not include a road surface recognition signal, extracting the current vehicle speed from the vehicle speed information;

[0135] If the current vehicle speed is less than a preset vehicle speed threshold, obtaining a speed difference between the current vehicle speed and the preset vehicle speed threshold;

[0136] determining a correction factor according to the speed difference;

[0137] The target damping coefficient is determined according to the correction coefficient and the maximum damping coefficient.

[0138] It should be noted that the maximum damping coefficient may be the maximum value of the damping coefficient supported by the electronically controlled shock absorber in the vehicle. The preset vehicle speed threshold may be pre-calibrated by the management personnel of the vehicle braking and shock absorbing equipment.

[0139] In actual use, if the obtainable braking-related signals do not include road surface recognition signals, the vehicle is actually unable to obtain road surface recognition information (or road surface recognition signals) and is unable to obtain road surface information. During initial braking, the road surface input vector changes greatly, and calculations based on previous road surface information will result in inaccurate road surface input vectors. At this time, it is actually difficult to use a four-degree-of-freedom half-car model for calculations. Therefore, the damping coefficient currently required can be determined directly based on the vehicle's current speed. Therefore, the current speed can be extracted from the vehicle speed information.

[0140] In actual application, the greater the vehicle speed, the greater the damping force required during braking. Therefore, if the current vehicle speed is greater than or equal to the preset vehicle speed threshold, it means that the vehicle speed is extremely high at this time. If braking occurs, the maximum damping force needs to be provided to reduce the pitch of the vehicle as much as possible. Therefore, the target damping coefficient can be set to the maximum damping coefficient.

[0141] If the current vehicle speed is less than the preset speed threshold, it means that the vehicle speed is relatively low at this time, and there is no need to directly use the maximum damping force. In order to determine the specific damping force to be used, the speed difference between the current vehicle speed and the preset speed threshold can be calculated. Then, the correction coefficient (0≤correction coefficient≤1) is determined according to the speed difference. Finally, the correction coefficient is multiplied by the maximum damping coefficient, and the product obtained is used as the target damping coefficient.

[0142] The correction coefficient is proportional to the current vehicle speed and inversely proportional to the speed difference. The corresponding relationship between the correction coefficient and the speed difference can be pre-set by the management personnel of the vehicle braking and vibration reduction equipment and stored in a difference coefficient mapping table. Then, determining the correction coefficient according to the speed difference can be to search the correction coefficient corresponding to the speed difference in the difference coefficient mapping table.

[0143] When setting the difference coefficient mapping table, in order to reduce the difficulty of calibration, multiple difference intervals may be set, and a corresponding correction coefficient may be set for each difference interval, which is not limited in this embodiment.

[0144] In a possible implementation of this embodiment, after step S30, the following may also be included:

[0145] When an emergency braking signal of the autonomous driving function is detected, extracting a target deceleration from the emergency braking signal;

[0146] determining a target nodding force according to the target deceleration;

[0147] A new target damping coefficient is generated according to the target nodding force, and the process returns to the step of controlling the electronically controlled shock absorber in the vehicle based on the target damping coefficient.

[0148] It should be noted that when the automatic driving function controls the braking of the vehicle, due to the influence of the algorithm, changes in obstacles (such as pedestrian movement, vehicle acceleration or deceleration, etc.), in some cases, even after previous braking, emergency braking may still be required to avoid obstacles. At this time, the automatic driving will send a corresponding emergency braking signal, and emergency braking will generally cause the vehicle to pitch more. In order to reduce the pitch at this time, when the emergency braking signal of the automatic driving function is detected, the target deceleration can be extracted from the emergency braking signal, and then the target nod force is calculated based on the target deceleration, and then a new target damping coefficient is generated based on the target nod force, and then the process returns to execute step S30.

[0149] For example, if the vehicle has an automatic driving function, an automatic driving controller (AD domain controller) will be set in the vehicle. At this time, if an emergency braking signal (AEB signal) issued by the AD domain controller is detected after the previous braking, the target deceleration a can be obtained according to the AEB signal. At this time, the target braking force F = ma, and the target nodding force F dive =F / (H*L). If the target nodding force is decomposed, then the target nodding force of the front wheel of the vehicle is f f,dive =F dive , the target nodding force of the rear wheel f r,dive =-F dive At this time, the target nodding force can be used as a simulated nodding force to be substituted into the four-degree-of-freedom half-car model for calculation to determine the pitch angle vector, and then the pitch control torque is determined according to the pitch angle vector, and then the new target damping coefficient is determined according to the pitch control torque, and finally, the execution returns to step S30 according to the new target damping coefficient;

[0150] Wherein, v is the current speed of the vehicle, t is the time it takes for the vehicle to contact the obstacle at the current speed, H is the height of the center of mass of the vehicle, and L is the wheelbase of the front and rear wheels of the vehicle.

[0151] In actual use, since the vehicle braking and shock absorbing equipment may only be able to obtain the automatic driving signal but not the road surface recognition signal, it will be impossible to determine the road surface input vector through the road surface recognition signal (such as obtaining the image from the front camera to determine the road surface input vector). Emergency braking generally takes a very short time, and the road surface input vector in a shorter time can be used as the road surface input vector for the next instant. Therefore, the current vehicle state parameters, pitch angle, external force input vector, etc. can be substituted into the four-degree-of-freedom half-car model for passive inference to calculate the road surface input vector. Afterwards, the road surface input vector and the target nodding force calculated according to the emergency braking signal are substituted into the four-degree-of-freedom half-car model for calculation, thereby determining the new target damping coefficient.

[0152] Among them, when passively calculating the road input vector, the external force input vector (i.e., BU in the above state equation) in the four-degree-of-freedom half-car model can be partially cleared, and the current relevant state information of the vehicle can be substituted into the four-degree-of-freedom passive half-car model to calculate the road input vector.

[0153] This embodiment provides a vehicle braking vibration reduction method. When calculating the target damping coefficient, different methods are used to calculate the target damping coefficient depending on whether the obtainable braking-related signals include a road surface recognition signal. This ensures that even if the obtainable braking-related signals are different, the electronically controlled shock absorber can still be reasonably controlled.

[0154] The present application also provides a vehicle braking and vibration reduction device, please refer to Figure 5 , the vehicle braking and vibration reduction device comprises:

[0155] A detection module 10, for determining an obtainable braking-related signal when an approaching obstacle is detected;

[0156] A determination module 20, configured to determine a target damping coefficient based on the braking-related signal and vehicle speed information;

[0157] The control module 30 is used to control the electronically controlled shock absorber in the vehicle based on the target damping coefficient.

[0158] The vehicle braking vibration reduction device provided by the present application adopts the vehicle braking vibration reduction method in the above embodiment, which can solve the technical problem of the hysteresis of the pitching phenomenon of the vehicle during braking in the control and adjustment of the electronically controlled shock absorber in the related technology. Compared with the prior art, the beneficial effects of the vehicle braking vibration reduction device provided by the present application are the same as the beneficial effects of the vehicle braking vibration reduction method provided by the above embodiment, and the other technical features of the vehicle braking vibration reduction device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0159] The present application provides a vehicle braking and vibration reduction device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the vehicle braking and vibration reduction method in the above-mentioned embodiment one.

[0160] Reference below Figure 6 , which shows a schematic diagram of the structure of a vehicle braking and vibration reduction device suitable for implementing the embodiment of the present application. The vehicle braking and vibration reduction device in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 6 The vehicle braking and vibration reduction device shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0161] like Figure 6As shown, the vehicle braking and vibration reduction device may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the vehicle braking and vibration reduction device are also stored. The processing device 1001, ROM1002, and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the vehicle braking and vibration reduction device to communicate with other devices wirelessly or by wire to exchange data. Although the figure shows a vehicle braking and vibration reduction device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or have alternatively.

[0162] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0163] The vehicle braking and vibration reduction device provided by the present application adopts the vehicle braking and vibration reduction method in the above embodiment, which can solve the technical problem of the hysteresis of the pitching phenomenon of the vehicle during braking in the control and adjustment of the electronically controlled shock absorber in the related technology. Compared with the prior art, the beneficial effects of the vehicle braking and vibration reduction device provided by the present application are the same as the beneficial effects of the vehicle braking and vibration reduction method provided by the above embodiment, and the other technical features in the vehicle braking and vibration reduction device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0164] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0165] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0166] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the vehicle braking vibration reduction method in the above-mentioned embodiment.

[0167] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0168] The computer-readable storage medium may be included in the vehicle braking and vibration reduction device; or may exist independently without being assembled into the vehicle braking and vibration reduction device.

[0169] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by the vehicle braking and shock absorbing device, the vehicle braking and shock absorbing device: determines an obtainable braking-related signal when an adjacent obstacle is detected; determines a target damping coefficient based on the braking-related signal and according to vehicle speed information; and controls the electronically controlled shock absorber in the vehicle based on the target damping coefficient.

[0170] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0171] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0172] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0173] The readable storage medium provided by the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned vehicle braking and vibration reduction method, and can solve the technical problem of the related art of controlling and adjusting the electronically controlled shock absorber and offsetting the hysteresis of the pitching phenomenon of the vehicle during braking. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the present application are the same as the beneficial effects of the vehicle braking and vibration reduction method provided by the above-mentioned embodiment, and will not be repeated here.

[0174] The present application also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the steps of the vehicle braking vibration reduction method as described above are implemented.

[0175] The computer program product provided by the present application can solve the technical problem of the related art in controlling and adjusting the electronically controlled shock absorber to offset the hysteresis of the pitching phenomenon of the vehicle during braking. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the vehicle braking vibration reduction method provided by the above embodiment, and will not be elaborated here.

[0176] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A vehicle braking vibration reduction method, characterized in that: The method comprises: determining available brake-related signals when an approaching obstacle is detected; Based on the brake-related signal, determining a target damping coefficient according to vehicle speed information; An electronically controlled shock absorber in the vehicle is controlled based on the target damping coefficient.

2. The vehicle braking vibration reduction method according to claim 1, characterized in that: The step of determining a target damping coefficient based on the braking-related signal and according to vehicle speed information includes: detecting whether the braking-related signal includes a road surface recognition signal; If the brake-related signal includes a road surface recognition signal, generating a simulated nodding force according to vehicle speed information; Substituting the simulated nodding force into the four-degree-of-freedom half-car model for calculation to generate a pitch angle vector; Determining a pitch control torque according to the pitch angle vector; A target damping coefficient is generated according to the pitch control moment.

3. The vehicle braking vibration reduction method according to claim 2, characterized in that: After detecting whether the braking-related signal includes a road surface recognition signal, the method further includes: If the brake-related signal does not include a road surface recognition signal, extracting the current vehicle speed from the vehicle speed information; If the current vehicle speed is less than a preset vehicle speed threshold, obtaining a speed difference between the current vehicle speed and the preset vehicle speed threshold; determining a correction factor according to the speed difference; A target damping coefficient is determined according to the correction coefficient and a maximum damping coefficient, wherein the maximum damping coefficient is a maximum value of the damping coefficient supported by the electronically controlled shock absorber in the vehicle.

4. The vehicle braking vibration reduction method according to claim 2, characterized in that: The determining the pitch control torque according to the pitch angle vector comprises: Get the pitch control type of the vehicle; Determining a torque determination method according to the pitch control type; The pitch control torque is determined according to the torque determination method and the pitch angle vector.

5. The vehicle braking vibration reduction method according to claim 2, characterized in that: Generating a target damping coefficient according to the pitch control moment includes: Get the vehicle suspension category of the vehicle; Obtaining a damping force generation method corresponding to the vehicle suspension type; According to the damping force generation method, a target damping coefficient is determined according to the pitch control moment.

6. The vehicle braking vibration reduction method according to claim 1, characterized in that: Before determining the simulated nodding force of the vehicle according to the speed information of the vehicle when an adjacent obstacle is detected, the method further includes: When an obstacle is detected by road recognition signals but no braking signal of the autonomous driving function is detected, the obstacle contact time is determined based on the vehicle speed information, and when the obstacle contact time is less than a preset time threshold, it is determined that an adjacent obstacle is detected; or, When it is determined that an obstacle is detected through the road recognition signal, but no change in the brake cylinder hydraulic pressure in the brake system is detected, the obstacle contact time is determined based on the vehicle speed information, and when the obstacle contact time is less than a preset time threshold, it is determined that an adjacent obstacle is detected; or, When a brake hydraulic pre-fill signal of the autonomous driving function is detected but an emergency braking signal of the autonomous driving function is not detected, it is determined that an adjacent obstacle is detected.

7. The vehicle braking vibration reduction method according to any one of claims 1 to 6, characterized in that: After the electronically controlled shock absorber in the vehicle is controlled based on the target damping coefficient, the method further includes: When an emergency braking signal of the autonomous driving function is detected, extracting a target deceleration from the emergency braking signal; determining a target nodding force according to the target deceleration; A new target damping coefficient is generated according to the target nodding force, and the process returns to the step of controlling the electronically controlled shock absorber in the vehicle based on the target damping coefficient.

8. A vehicle braking and vibration reduction device, characterized in that: The device comprises: A detection module, for determining an obtainable braking-related signal when an approaching obstacle is detected; A determination module, configured to determine a target damping coefficient based on the braking-related signal and vehicle speed information; A control module is used to control an electronically controlled shock absorber in a vehicle based on the target damping coefficient.

9. A vehicle braking and vibration reduction device, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the vehicle braking vibration reduction method according to any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the vehicle braking vibration reduction method according to any one of claims 1 to 7 are implemented.

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