Auxiliary braking control method and device, equipment and storage medium

Abstract

The invention discloses an auxiliary braking control method, device and equipment and a storage medium, and relates to the technical field of vehicles, and the auxiliary braking control method comprises the steps that when the current braking state is a constant-speed braking state and the whole vehicle working condition parameters meet the constant-speed braking condition, the target speed difference is determined according to the target braking vehicle speed and the current driving speed; a target speed regulation torque is obtained according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relation; and performing auxiliary braking control on the vehicle according to the target speed regulation torque. Different braking torques are adaptively adjusted according to different load slopes, under the condition that the set vehicle speed is reached, the braking torque gradually approaches 0, the vehicle speed is kept constant, the continuous and effective braking effect can be guaranteed without operation of a driver, the auxiliary braking torque is adaptively adjusted, the auxiliary braking control method adapts to the full-slope and full-load working condition, and the driving safety is improved. The problem that the auxiliary braking torque is too large or too small and cannot be adjusted is solved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to auxiliary braking control methods, devices, equipment and storage media. Background Art

[0002] Fuel vehicles achieve auxiliary braking deceleration function through retarders or in-cylinder brakes. New energy vehicles have no engine structure and generate negative torque deceleration braking through the reverse action of the motor. The switch allows the driver to select the auxiliary braking switch or even different levels of auxiliary braking deceleration effect. However, under different loads and slopes, too little torque will lead to insufficient deceleration of the vehicle and require brake assistance. Too much torque will have a sharp deceleration effect and require the accelerator to accelerate. Timely distinguishing between multiple levels of auxiliary braking still cannot adapt to full-slope and full-load conditions and requires driver assistance, which causes inconvenience. Therefore, how to solve the problem that the existing auxiliary braking control method cannot adapt to full-slope and full-load conditions has become an urgent problem to be solved. Summary of the invention

[0003] The main purpose of this application is to provide an auxiliary braking control method, device, equipment and storage medium, aiming to solve the technical problem that the existing auxiliary braking control method cannot adapt to full-slope and full-load conditions.

[0004] To achieve the above objectives, the present application proposes an auxiliary braking control method, the auxiliary braking control method comprising: When the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions, the target speed difference is determined according to the target braking speed and the current driving speed; Obtaining a target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relationship; Auxiliary braking control is performed on the vehicle according to the target speed regulation torque.

[0005] In one embodiment, when the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking condition, the step of determining the target speed difference according to the target braking speed and the current driving speed includes: When the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions, the brake pedal signal is monitored; determining a corresponding updated braking vehicle speed according to the brake pedal signal; adjusting the preset braking speed according to the updated braking speed to obtain a target braking speed; A target speed difference is determined according to the target braking vehicle speed and the current traveling speed.

[0006] In one embodiment, the step of obtaining the target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relationship includes: determining a corresponding target rotation speed difference according to the target speed difference; Determine a target deceleration value and a target adjustment parameter value according to the current vehicle load, the current vehicle slope and a preset mapping relationship; The target speed regulation torque is obtained according to the target speed difference, the target deceleration value and the target regulation parameter value.

[0007] In one embodiment, before the step of performing auxiliary braking control according to the target speed regulation torque, the method further includes: Determine the target limit torque based on the battery limit torque, motor feedback torque, vehicle limit torque and rear axle protection torque; Comparing the target limit torque with the target speed regulation torque to obtain a torque comparison result; When the torque comparison result is that the target speed regulating torque is less than or equal to the target limit torque, the step of performing auxiliary braking control on the vehicle according to the target speed regulating torque is performed.

[0008] In one embodiment, when the current braking state is the auxiliary braking state and the vehicle operating state parameters meet the constant speed braking condition, before the step of determining the target speed difference according to the target braking speed and the current driving speed, the step further includes: Get the gear resistance value corresponding to the current switch gear; Calculate the voltage according to the gear resistance value to obtain a current voltage signal; Convert the current voltage signal according to a preset conversion method to obtain a current analog value; When the current analog value is within the target analog value range, it is determined that the current braking state is a constant speed braking state.

[0009] In one embodiment, when the current braking state is the auxiliary braking state and the vehicle operating state parameters meet the constant speed braking condition, before the step of determining the target speed difference according to the target braking speed and the current driving speed, the step further includes: Determine the current logical gear, vehicle speed and basic vehicle parameters according to the vehicle operating condition parameters; When the current logical gear is in the target logical gear, the vehicle speed is in the target speed range, and the basic parameters of the vehicle meet the auxiliary braking conditions, it is determined that the vehicle operating parameters meet the constant speed braking conditions.

[0010] In one embodiment, after the step of performing auxiliary braking control according to the target speed regulation torque, the method further includes: When a vehicle fault is detected and the fault level is a target level, a power-off request instruction is generated; The vehicle power-off process is executed according to the request power-off instruction.

[0011] In addition, to achieve the above-mentioned purpose, the present application also proposes an auxiliary brake control device, the auxiliary brake control device comprising: A processing module, used for determining a target speed difference according to a target braking speed and a current driving speed when the current braking state is a constant speed braking state and the vehicle operating condition parameters meet the constant speed braking condition; The processing module is further used to obtain a target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relationship; The braking module is used to perform auxiliary braking control according to the target speed regulation torque.

[0012] In addition, to achieve the above-mentioned purpose, the present application also proposes an auxiliary braking control device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, and the computer program is configured to implement the steps of the auxiliary braking control method described above.

[0013] 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 auxiliary braking control method described above are implemented.

[0014] 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 auxiliary braking control method described above are implemented.

[0015] The present application determines the target speed difference according to the target braking speed and the current driving speed when the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions; obtains the target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and the preset mapping relationship; and performs auxiliary braking control on the vehicle according to the target speed regulating torque. By adaptively adjusting different braking torques according to different load slopes, when the set vehicle speed is reached, the braking torque gradually approaches 0, maintaining the vehicle constant speed, and ensuring the continuous and effective braking effect without the need for driver operation. The auxiliary braking torque is adaptively adjusted, and the auxiliary braking control method is adapted to the full-slope and full-load conditions, avoiding the problem of the auxiliary braking torque being too large or too small and unable to be adjusted. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] 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.

[0017] 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.

[0018] Figure 1 A schematic diagram of a flow chart provided for the first embodiment of the auxiliary braking control method of the present application; Figure 2 A schematic diagram of the switch detection principle provided in Embodiment 1 of the auxiliary braking control method of the present application; Figure 3 A schematic diagram of constant speed auxiliary braking conditions provided in Example 1 of the auxiliary braking control method of the present application; Figure 4 A schematic diagram of a flow chart provided for the second embodiment of the auxiliary braking control method of the present application; Figure 5 A schematic diagram of a constant speed auxiliary braking control process provided in Embodiment 2 of the auxiliary braking control method of the present application; Figure 6 A brief flowchart of the auxiliary braking control method provided in Example 1 of the present application; Figure 7 This is a schematic diagram of the module structure of the auxiliary brake control device according to an embodiment of the present application; Figure 8 Schematic diagram of the device structure of the hardware operating environment involved in the auxiliary braking control method in the embodiment of the present application.

[0019] 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

[0020] 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.

[0021] 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.

[0022] The main solution of the embodiment of the present application is: when the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions, the target speed difference is determined according to the target braking speed and the current driving speed; the target speed regulation torque is obtained according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relationship; and auxiliary braking control of the vehicle is performed according to the target speed regulation torque.

[0023] Fuel vehicles achieve auxiliary braking deceleration function through retarders or in-cylinder brakes. New energy vehicles have no engine structure and generate negative torque deceleration braking through the reverse action of the motor. The switch allows the driver to select the auxiliary braking switch or even different levels of auxiliary braking deceleration effect. However, under different loads and slopes, too little torque will lead to insufficient deceleration of the vehicle and require brake assistance. Too much torque will have a sharp deceleration effect and require the accelerator to accelerate. Timely distinguishing between multiple levels of auxiliary braking still cannot adapt to full-slope and full-load conditions and requires driver assistance, which causes inconvenience. Therefore, how to solve the problem that the existing auxiliary braking control method cannot adapt to full-slope and full-load conditions has become an urgent problem to be solved.

[0024] The present application determines the target speed difference according to the target braking speed and the current driving speed when the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions; obtains the target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and the preset mapping relationship; and performs auxiliary braking control on the vehicle according to the target speed regulating torque. By adaptively adjusting different braking torques according to different load slopes, when the set vehicle speed is reached, the braking torque gradually approaches 0, maintaining the vehicle constant speed, and ensuring the continuous and effective braking effect without the need for driver operation. The auxiliary braking torque is adaptively adjusted, and the auxiliary braking control method is adapted to the full-slope and full-load conditions, avoiding the problem of the auxiliary braking torque being too large or too small and unable to be adjusted.

[0025] It should be noted that the execution subject of this embodiment may be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an auxiliary brake control device capable of realizing the above functions, etc. The following takes the auxiliary brake control device as an example of the execution subject, such as a vehicle controller, to illustrate this embodiment and the following embodiments.

[0026] Based on this, the embodiment of the present application provides an auxiliary braking control method, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the auxiliary braking control method of the present application.

[0027] In this embodiment, the auxiliary braking control method includes steps S10 to S30: Step S10, when the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions, determining a target speed difference according to the target braking speed and the current driving speed; It should be noted that the present embodiment can set a constant vehicle speed according to the driving operation switch, and use fixed speed auxiliary braking to recover electricity to increase the cruising range. The auxiliary braking process does not require the driver to operate the brakes or accelerator, and is adaptively adjusted only when the driver needs to adjust the constant vehicle speed, which facilitates the driving experience and avoids frequent braking that causes brake overheating and the auxiliary braking torque being too large or too small to adjust.

[0028] It can be understood that the current braking state includes constant speed braking state and multi-speed braking state. The constant speed braking state refers to the state of the vehicle turning on constant speed auxiliary braking, and the multi-speed braking state refers to the state of the vehicle turning on multi-speed auxiliary braking. The vehicle operating parameters include vehicle speed, current gearbox gear, ABS state, motor speed, battery state, current load mode, etc. The constant speed braking condition refers to the pre-set condition for turning on constant speed auxiliary braking. The constant speed braking condition includes auxiliary braking condition. The target braking speed refers to the speed maintained by controlling the constant speed braking of the vehicle. The current driving speed refers to the current speed of the vehicle. The target speed difference refers to the difference between the current driving speed and the target braking speed.

[0029] In a specific implementation, when the current braking state is that the vehicle turns on the constant speed auxiliary braking and the vehicle operating parameters meet the pre-set conditions for turning on the constant speed auxiliary braking, it indicates that the vehicle controller determines that the constant speed auxiliary braking state is valid and starts to enter the constant speed auxiliary braking control, and then calculates the difference between the speed maintained by the constant speed braking of the vehicle and the current speed of the vehicle to obtain the target speed difference.

[0030] In a feasible implementation manner, step S10 may include steps A11 to A14: Step A11, obtaining the gear resistance value corresponding to the current switch gear; It can be understood that the current switch position refers to the position corresponding to the multi-position switch, and the position resistance value refers to the resistance value corresponding to the current switch position.

[0031] In a specific implementation, the vehicle controller obtains the gear corresponding to the multi-gear switch, and then determines the current braking state of the vehicle according to the resistance value of the gear corresponding to the multi-gear switch.

[0032] Step A12, calculating the voltage according to the gear resistance value to obtain a current voltage signal; It can be understood that the current voltage signal refers to the voltage value signal corresponding to the gear of the current multi-gear switch. Different gears correspond to different resistance values. Then the vehicle controller distinguishes different gears according to the detected voltage signal, that is, calculates the voltage value according to the resistance value corresponding to the gear of the current multi-gear switch, and finally obtains the voltage value signal corresponding to the gear of the current multi-gear switch.

[0033] Step A13, converting the current voltage signal according to a preset conversion method to obtain a current analog value; It can be understood that the preset conversion method refers to an analog-to-digital conversion (AD) method, and the current analog value refers to a digital value after AD conversion.

[0034] In a specific implementation, the voltage value signal corresponding to the current gear position of the multi-gear switch is converted by analog-to-digital conversion to obtain a digital value after AD conversion, that is, a voltage digital value corresponding to the current voltage signal.

[0035] Step A14, when the current analog value is within the target analog value range, determining that the current braking state is a constant speed braking state.

[0036] It can be understood that the target analog value range refers to the analog value range corresponding to when the constant speed auxiliary braking is effective.

[0037] In a specific implementation, the digital value corresponding to the current voltage signal after AD conversion is compared with the analog range corresponding to the constant speed auxiliary braking being effective. When the digital value corresponding to the current voltage signal after AD conversion is within the analog range corresponding to the constant speed auxiliary braking being effective, it indicates that the current braking state is a constant speed braking state.

[0038] It should be noted that due to different functional requirements of different drivers, multi-speed auxiliary braking and constant speed auxiliary braking can be turned on separately according to the driver's operation, and two functions can be realized through the multiplexing and compatibility of multi-speed switches. For example, in the N-speed switch, the OFF gear turns off both functions. When it is turned on to the 1st gear, it is the constant speed auxiliary braking gear, and the multi-speed energy recovery is the OFF gear. When it is turned on to the 2-N gear, it is the gear for turning on the multi-speed auxiliary braking. Different auxiliary braking torques are requested according to different gears. The switch gear status (taking 5th gear as an example) is shown in Table 1, and the switch detection principle is as follows Figure 2 As shown, the power supply is specifically provided by the battery, the analog input interface of the vehicle controller is in different gears through the switch, different resistors are connected to the monitoring point, different voltage signals are detected, the hardware bottom layer converts different analog quantities through AD conversion, and the application layer software determines that different ranges of analog quantities are different gears.

[0039] Table 1:

[0040] In a feasible implementation manner, step S10 may include steps B11 to B12: Step B11, determining the current logical gear position, vehicle speed and basic vehicle parameters according to the vehicle operating condition parameters; It can be understood that the current logical gear refers to the vehicle's driving logical gear, including: D gear, N gear and R gear, etc. The vehicle driving speed refers to the current vehicle driving speed, and the vehicle's basic parameters include the accelerator pedal signal status, constant speed descent status and brake pedal signal status, etc.

[0041] In the specific implementation, the vehicle's driving logic gear, current vehicle speed, accelerator pedal signal status, constant speed descent status, brake pedal signal status, etc. are determined according to parameters such as vehicle speed, current transmission gear, ABS status, motor speed, battery status, current load mode, etc.

[0042] Step B12, when the current logical gear is in the target logical gear, the vehicle speed is in the target speed range, and the basic parameters of the vehicle meet the auxiliary braking conditions, determine that the vehicle operating parameters meet the constant speed braking conditions.

[0043] It can be understood that the target logical gear refers to the vehicle's driving gear being D gear, the target speed range refers to the speed range used to determine whether the constant speed braking condition is met, and the auxiliary braking condition refers to the condition for turning on the constant speed auxiliary braking.

[0044] In a specific implementation, when the current logical gear is in D gear, the current vehicle speed is in the speed range used to determine whether the constant speed braking conditions are met, and the accelerator pedal signal state, constant speed downhill state, and brake pedal signal state all meet the conditions for starting constant speed auxiliary braking, it is determined that the vehicle operating parameters meet the constant speed braking conditions.

[0045] It should be noted that if Figure 3As shown, constant speed auxiliary braking is part of the drive control and energy recovery function. It must meet relevant conditions to be turned on, otherwise there will be conflicts with other functions or function failure. The following conditions must be met: the current logical gear is D gear (N / R does not need to be turned on, otherwise there will be a functional conflict with driving in N / R gear); V1 ≥ vehicle speed ≥ V2 km / h (constant speed auxiliary braking is unnecessary at high speeds, and constant speed auxiliary braking at low speeds will cause the vehicle to quickly drop to 0, which is not conducive to function realization); the accelerator pedal signal is invalid (stepping on the accelerator is a positive drive acceleration); the constant speed downhill switch is valid; unlimited power, limp, power-off request (the vehicle has a speed limit and power limit request power-off fault, and the vehicle must be restricted first to ensure safety); the vehicle is in the driving READY high-voltage state (the high-voltage state is before the drive function The SOC of BMS is less than or equal to the high SOC setting value (when the SOC is high, the battery can be recharged with a small power to avoid overcharging the battery); there is no ABS communication failure and the ABS is not activated; (the ABS anti-skid function is turned on, and auxiliary braking must be prohibited); the vehicle has not entered the cruise state (the cruise function has priority); the graded auxiliary brake switch and the auxiliary brake switch are invalid (to avoid conflicts in the braking functions); the brake pedal signal is invalid (the driver's driving braking behavior operation gives priority to satisfying the driving braking needs); when the above conditions are met at the same time, the vehicle controller determines that the constant speed auxiliary braking state is valid and starts to enter the constant speed auxiliary braking control.

[0046] It should be noted that the vehicle controller detects the auxiliary brake switch and meets the constant speed auxiliary braking conditions. It sends a related message signal and the instrument lights up as a prompt. Because this function belongs to the energy recovery braking function, the brake lights need to be lit through this signal to remind pedestrians and vehicles.

[0047] Step S20, obtaining a target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relationship; It can be understood that the current vehicle load refers to the weight carried by the vehicle during transportation, the current vehicle slope refers to the slope of the current vehicle, the preset mapping relationship refers to the pre-set mapping relationship of different load ranges, different slope ranges, deceleration values, and PID adjustment parameter values, and the target speed regulation torque refers to the torque required to adjust the vehicle speed.

[0048] In the specific implementation, the torque is calculated based on the difference between the current driving speed and the target braking speed, the weight carried by the vehicle during transportation, and the current slope of the vehicle, combined with the pre-set mapping relationship between different load ranges, different slope ranges, deceleration values, and PID adjustment parameter values, and finally the target speed regulation torque, i.e., the target speed regulation torque, is obtained.

[0049] Step S30: performing auxiliary braking control on the vehicle according to the target speed regulation torque.

[0050] It can be understood that the vehicle speed is adjusted according to the torque required to adjust the vehicle speed to achieve constant speed auxiliary braking control of the vehicle, that is, the current vehicle speed is intelligently and smoothly adjusted to the target speed by torque control according to different loads and slopes.

[0051] In a feasible implementation manner, step S30 may include steps A31 to A33: Step A31, determining a target torque limit according to the battery torque limit, the motor feedback torque, the vehicle torque limit and the rear axle protection torque; It can be understood that the battery limiting torque refers to the torque limit corresponding to the battery's allowable charging peak power, the motor feedback torque refers to the motor's allowable feedback torque, the rear axle protection torque refers to the rear axle protection anti-drag torque, the vehicle limiting torque refers to the vehicle's maximum torque parameter limit, and the target limiting torque refers to the maximum auxiliary braking protection torque size.

[0052] In the specific implementation, the minimum value is taken as the protection torque of maximum auxiliary braking, i.e., the target limit torque, based on the torque limit corresponding to the allowable peak charging power of the battery, the allowable feedback torque of the motor, the rear axle protection anti-drag torque and the maximum torque parameter limit of the vehicle.

[0053] Step A32, comparing the target limit torque with the target speed regulation torque to obtain a torque comparison result; It can be understood that the torque comparison result refers to the comparison result between the target limit torque and the target speed regulation torque.

[0054] In the specific implementation, in order to ensure the safety of the whole vehicle, the vehicle's torque needs to be limited when the constant speed auxiliary braking function is turned on, and then the torque required to adjust the vehicle speed is compared with the protection torque of the maximum auxiliary braking, and finally the torque comparison result is obtained.

[0055] Step A33, when the torque comparison result is that the target speed regulating torque is less than or equal to the target limit torque, executing the step of performing auxiliary braking control on the vehicle according to the target speed regulating torque.

[0056] In a specific implementation, when the torque comparison result is that the target speed regulation torque is less than or equal to the target limit torque, it indicates that the target speed regulation torque meets the torque limit requirement, and then the step of performing auxiliary braking control on the vehicle according to the target speed regulation torque is executed.

[0057] In a feasible implementation manner, step S30 may include steps B31-B32: Step B31, when a vehicle fault is detected and the fault level is the target level, generating a power-off request instruction; It can be understood that the target level is used to describe a serious fault level, and the power-off request instruction refers to a request to control the vehicle to power off.

[0058] In a specific implementation, if a serious fault is detected or other key systems (such as BMS, motor controller, etc.) request power-off, the power-off process is executed first.

[0059] Step B32, executing the vehicle power-off process according to the request power-off instruction.

[0060] In a specific implementation, the vehicle is controlled to execute a vehicle power-off process according to a request for controlling the vehicle power-off, so as to ensure the safety of the vehicle.

[0061] It should be noted that the vehicle controller, as a constant speed auxiliary braking control unit, takes into account the safety protection of the vehicle. When the constant speed auxiliary braking function is turned on, it is also necessary to detect the allowable charging peak power of the battery (converted into torque limit), the allowable feedback torque of the motor, the rear axle protection reverse torque and the maximum torque parameter limit of the vehicle, and take the smaller one as the maximum auxiliary braking torque protection; at the same time, detect the fault status of the battery, motor, high-voltage accessories (steering, inflation, DCAC, thermal management, etc.), gearbox, motor controller, etc. and communication timeout identification to perform fault limiting torque protection; detect the status of EBS, ESC, and ABS to respond to anti-skid safety requests first; if a serious fault is detected or other key systems (such as BMS, motor controller, etc.) request to power off, the power-off process will be executed first.

[0062] This embodiment determines the target speed difference according to the target braking speed and the current driving speed when the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions; obtains the target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and the preset mapping relationship; and performs auxiliary braking control on the vehicle according to the target speed regulating torque. By adaptively adjusting different braking torques according to different load slopes, when the set vehicle speed is reached, the braking torque gradually approaches 0, maintaining the constant speed of the vehicle, and ensuring the continuous and effective braking effect without the need for driver operation. The auxiliary braking torque is adaptively adjusted, and the auxiliary braking control method is adapted to the full-slope and full-load conditions, avoiding the problem of the auxiliary braking torque being too large or too small and unable to be adjusted.

[0063] 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 be referred to the above introduction, and will not be repeated in the following. Figure 4 , step S10 in the auxiliary braking control method includes steps S11 to S14: Step S11, when the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions, monitoring the brake pedal signal; It is understood that the brake pedal signal refers to a signal used by the vehicle control system to detect the extent to which the driver presses the brake pedal.

[0064] In the specific implementation, when the current braking state is the constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions, it indicates that the vehicle controller determines that the constant speed auxiliary braking state is valid and starts to enter the constant speed auxiliary braking control. The initial state constant speed auxiliary braking target speed is 0. When the constant speed auxiliary braking state is valid, the current speed is used as the constant target speed. In order to facilitate the driver to adjust the constant target speed, a new driving operation (brake or accelerator pedal operation) is added as a condition for updating the target speed, and then the brake pedal signal or the accelerator pedal signal is monitored to determine whether the target speed needs to be updated.

[0065] Step S12, determining a corresponding updated braking vehicle speed according to the brake pedal signal; It can be understood that the updated braking vehicle speed refers to the vehicle speed of the constant speed auxiliary brake that needs to be updated.

[0066] In a specific implementation, when a brake pedal signal or an accelerator pedal signal is detected, it indicates that the driver has a need to adjust a constant target vehicle speed, and then the corresponding vehicle speed when the driver steps on the brake pedal or the accelerator pedal is obtained, and the constant speed auxiliary braking speed that needs to be updated is obtained.

[0067] Step S13, adjusting the preset braking speed according to the updated braking speed to obtain a target braking speed; It can be understood that the preset braking speed refers to the constant speed auxiliary braking target speed in the initial state (0 is taken as an example in this embodiment), and the target braking speed refers to the updated constant speed auxiliary braking target speed.

[0068] In a specific implementation, the constant speed auxiliary braking target vehicle speed in the initial state is adjusted according to the constant speed auxiliary braking vehicle speed that needs to be updated to obtain an updated constant speed auxiliary braking target vehicle speed, ie, a target braking vehicle speed.

[0069] Step S14, determining a target speed difference according to the target braking speed and the current driving speed.

[0070] It can be understood that the target speed difference is obtained by calculating the difference between the speed maintained by the constant speed braking of the vehicle and the current speed of the vehicle.

[0071] It should be noted that the initial constant speed assist braking target speed is 0. When the constant speed assist braking state is valid, the current speed is used as the constant target speed. In order to facilitate the driver to adjust the constant target speed, a new driving operation (brake or accelerator pedal operation) is added as a condition for updating the target speed: when the constant speed assist braking state is valid, and the brake pedal signal is valid, or the accelerator pedal signal is valid, the current speed is updated as the constant downhill set speed. When the constant speed assist braking state is invalid, the constant downhill set speed is maintained. After power off, the constant downhill set speed defaults to 0.

[0072] In a feasible implementation manner, step S20 may further include steps S21 to S23: Step S21, determining a corresponding target speed difference according to the target speed difference; It can be understood that the target speed difference refers to the vehicle motor speed difference corresponding to the target speed difference.

[0073] In a specific implementation, in order to accurately calculate the torque required for speed regulation, the difference between the current driving speed and the target braking speed is converted into a corresponding vehicle motor speed difference for accurate calculation.

[0074] Step S22, determining a target deceleration value and a target adjustment parameter value according to the current vehicle load, the current vehicle slope and a preset mapping relationship; It can be understood that the target deceleration value refers to the deceleration value corresponding to the current vehicle load and the current vehicle slope, and the target adjustment parameter value refers to the PID adjustment parameter value corresponding to the current vehicle load and the current vehicle slope.

[0075] In the specific implementation, according to the weight carried by the vehicle during transportation and the current slope of the vehicle, the three-dimensional table lookup method is used to search in the pre-set mapping relationship of different ranges of load, different ranges of slope, deceleration value, and PID adjustment parameter value to obtain the deceleration value and PID adjustment parameter value corresponding to the current vehicle load and the current vehicle slope.

[0076] Step S23, obtaining a target speed regulating torque according to the target speed difference, the target deceleration value and the target regulating parameter value.

[0077] In the specific implementation, the torque is calculated based on the vehicle motor speed difference corresponding to the target speed difference combined with the deceleration value and PID adjustment parameter value corresponding to the current vehicle load and the current vehicle slope to obtain the torque required to adjust the vehicle speed, that is, the target speed regulation torque.

[0078] It should be noted that if Figure 5As shown in the figure, constant speed downhill control allows the driver to drive the vehicle at a preset speed without stepping on the accelerator / brake pedal. The VCU detects that the vehicle state meets the constant speed auxiliary braking condition, records the current speed as the constant speed downhill preset speed, and enters the constant speed downhill function. When it is detected that the current speed is greater than the constant target speed, the VCU calculates the corresponding braking torque, and the MCU executes the torque to maintain the preset speed; when it is detected that the current speed is less than or equal to the constant target speed, the VCU requests a torque of 0. Constant speed auxiliary braking needs to detect the difference between the current vehicle speed and the constant speed target speed in real time as input, and select different adjustment deceleration curves based on the current load and slope, and convert the speed difference into a speed difference, as shown in Table 2. Different ranges of loads and different ranges of slopes are set by the three-dimensional table lookup method, and the corresponding deceleration value is found as the slope of the torque change, and the adapted torque change step is found. By finding the corresponding PID adjustment parameter value, the torque is calculated by the speed difference. The larger the speed difference, the greater the torque output, and the smaller the speed difference, the torque gradually approaches 0. The torque change rate is adjusted according to the deceleration and PID, and the current vehicle speed can be adjusted to the target speed in the form of torque control in an intelligent and smooth manner according to different loads and slopes.

[0079] Table 2:

[0080] In this embodiment, the corresponding target speed difference is determined according to the target speed difference; the target deceleration value and the target adjustment parameter value are determined according to the current vehicle load, the current vehicle slope and the preset mapping relationship; and the target speed adjustment torque is obtained according to the target speed difference, the target deceleration value and the target adjustment parameter value. In this way, the accuracy of calculating the torque required for speed regulation is improved.

[0081] This embodiment monitors the brake pedal signal when the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions; determines the corresponding updated braking speed according to the brake pedal signal; adjusts the preset braking speed according to the updated braking speed to obtain the target braking speed; and determines the target speed difference according to the target braking speed and the current driving speed. In the above manner, when the constant speed auxiliary braking is turned on, the deceleration and torque change rate can be adaptively adjusted according to the load and slope, and gradually adjusted from the current speed to the target speed smoothly without the need for driver operation, avoiding the problem of the auxiliary braking torque being too large or too small to be adjusted and the problem of the driver overheating due to frequent braking, which is convenient for driving experience.

[0082] For example, in order to help understand the implementation process of the auxiliary braking control method obtained by combining this embodiment with the above-mentioned embodiment 1, please refer to Figure 6 , Figure 6A brief flow diagram of an auxiliary braking control method is provided. Specifically, the vehicle turns the key to high pressure, shifts to forward gear D, steps on the accelerator to drive to a certain speed, the multi-stage auxiliary brake switch is in gear 1, releases the accelerator and brake, meets the constant speed auxiliary braking conditions, enters constant speed auxiliary braking control, calculates the auxiliary braking torque according to the current speed and target speed, load and slope identification, requests the MCU to execute the auxiliary braking torque, and the motor executes and adjusts the speed accordingly. Start - high pressure - gear D - step on the accelerator / brake to the appropriate speed - no accelerator / brake - constant speed auxiliary braking conditions are met - calculate auxiliary braking torque request MCU - motor execution (any condition is not met - end) - end.

[0083] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the auxiliary braking control method of the present application. More simple transformations based on this technical concept are all within the protection scope of the present application.

[0084] This application also provides an auxiliary brake control device, please refer to Figure 7 , the auxiliary brake control device comprises: The processing module 10 is used to determine the target speed difference according to the target braking speed and the current driving speed when the current braking state is a constant speed braking state and the vehicle operating condition parameters meet the constant speed braking condition; The processing module 10 is further used to obtain a target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relationship; The braking module 20 is used to perform auxiliary braking control according to the target speed regulation torque.

[0085] Optionally, the processing module 10 is further used for: When the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions, the brake pedal signal is monitored; determining a corresponding updated braking vehicle speed according to the brake pedal signal; adjusting the preset braking speed according to the updated braking speed to obtain a target braking speed; A target speed difference is determined according to the target braking vehicle speed and the current traveling speed.

[0086] Optionally, the processing module 10 is further used for: determining a corresponding target rotation speed difference according to the target speed difference; Determine a target deceleration value and a target adjustment parameter value according to the current vehicle load, the current vehicle slope and a preset mapping relationship; The target speed regulation torque is obtained according to the target speed difference, the target deceleration value and the target regulation parameter value.

[0087] Optionally, the braking module 20 is further used for: Determine the target limit torque based on the battery limit torque, motor feedback torque, vehicle limit torque and rear axle protection torque; Comparing the target limit torque with the target speed regulation torque to obtain a torque comparison result; When the torque comparison result is that the target speed regulating torque is less than or equal to the target limit torque, the step of performing auxiliary braking control on the vehicle according to the target speed regulating torque is performed.

[0088] Optionally, the processing module 10 is further used for: Get the gear resistance value corresponding to the current switch gear; Calculate the voltage according to the gear resistance value to obtain a current voltage signal; Convert the current voltage signal according to a preset conversion method to obtain a current analog value; When the current analog value is within the target analog value range, it is determined that the current braking state is a constant speed braking state.

[0089] Optionally, the processing module 10 is further used for: Determine the current logical gear, vehicle speed and basic vehicle parameters according to the vehicle operating condition parameters; When the current logical gear is in the target logical gear, the vehicle speed is in the target speed range, and the basic parameters of the vehicle meet the auxiliary braking conditions, it is determined that the vehicle operating parameters meet the constant speed braking conditions.

[0090] Optionally, the braking module 20 is further used for: When a vehicle fault is detected and the fault level is a target level, a power-off request instruction is generated; The vehicle power-off process is executed according to the request power-off instruction.

[0091] The auxiliary brake control device provided by the present application adopts the auxiliary brake control method in the above embodiment, which can solve the technical problem that the existing auxiliary brake control method cannot adapt to the full-slope and full-load working conditions. Compared with the prior art, the beneficial effects of the auxiliary brake control device provided by the present application are the same as the beneficial effects of the auxiliary brake control method provided by the above embodiment, and the other technical features in the auxiliary brake control device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0092] The present application provides an auxiliary braking control device, which includes: at least one processor; and a memory that is communicatively connected to the at least one processor; wherein the memory stores instructions that can be executed 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 auxiliary braking control method in the above-mentioned embodiment one.

[0093] Reference below Figure 8 , which shows a schematic diagram of the structure of an auxiliary brake control device suitable for implementing the embodiment of the present application. The auxiliary brake control 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 8 The auxiliary brake control 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.

[0094] like Figure 8As shown, the auxiliary brake control device may include a processing device 1001 (such as 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 auxiliary brake control 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 auxiliary brake control device to communicate with other devices wirelessly or by wire to exchange data. Although the auxiliary brake control device with various systems is shown in the figure, 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.

[0095] 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.

[0096] The auxiliary brake control device provided by the present application adopts the auxiliary brake control method in the above embodiment, which can solve the technical problem that the existing auxiliary brake control method cannot adapt to the full-slope and full-load working conditions. Compared with the prior art, the beneficial effects of the auxiliary brake control device provided by the present application are the same as the beneficial effects of the auxiliary brake control method provided by the above embodiment, and the other technical features in the auxiliary brake control device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0097] 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.

[0098] 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.

[0099] 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 auxiliary braking control method in the above-mentioned embodiment.

[0100] 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: Random Access Memory), a read-only memory (ROM: Read Only Memory), an erasable programmable read-only memory (EPROM: Erasable Programmable Read Only Memory or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM: CD-Read Only Memory), 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, which may 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: Radio Frequency), etc., or any suitable combination of the above.

[0101] The computer-readable storage medium may be included in the auxiliary brake control device; or may exist independently without being assembled into the auxiliary brake control device.

[0102] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned one or more programs are executed by the auxiliary braking control device, the auxiliary braking control device: when the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions, determines the target speed difference according to the target braking speed and the current driving speed; obtains the target speed regulation torque according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relationship; and performs auxiliary braking control on the vehicle according to the target speed regulation torque.

[0103] 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).

[0104] 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.

[0105] 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.

[0106] The readable storage medium provided in the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned auxiliary braking control method, and can solve the technical problem that the existing auxiliary braking control method cannot adapt to the full-slope full-load working condition. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in the present application are the same as the beneficial effects of the auxiliary braking control method provided in the above-mentioned embodiment, and will not be repeated here.

[0107] 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 auxiliary braking control method as described above are implemented.

[0108] The computer program product provided by the present application can solve the technical problem that the existing auxiliary braking control method cannot adapt to the full-slope and full-load working conditions. 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 auxiliary braking control method provided by the above embodiment, which will not be repeated here.

[0109] 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. An auxiliary braking control method, characterized in that: The auxiliary braking control method comprises: When the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions, the target speed difference is determined according to the target braking speed and the current driving speed; Obtaining a target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relationship; Auxiliary braking control is performed on the vehicle according to the target speed regulation torque.

2. The method according to claim 1, characterized in that The step of determining the target speed difference according to the target braking speed and the current driving speed when the current braking state is a constant speed braking state and the vehicle operating condition parameters meet the constant speed braking condition comprises: When the current braking state is a constant speed braking state and the vehicle operating parameters meet the constant speed braking conditions, the brake pedal signal is monitored; determining a corresponding updated braking vehicle speed according to the brake pedal signal; adjusting the preset braking speed according to the updated braking speed to obtain a target braking speed; A target speed difference is determined according to the target braking vehicle speed and the current traveling speed.

3. The method according to claim 1, characterized in that The step of obtaining the target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relationship comprises: determining a corresponding target rotation speed difference according to the target speed difference; Determine a target deceleration value and a target adjustment parameter value according to the current vehicle load, the current vehicle slope and a preset mapping relationship; The target speed regulation torque is obtained according to the target speed difference, the target deceleration value and the target regulation parameter value.

4. The method according to claim 1, characterized in that Before the step of performing auxiliary braking control according to the target speed regulating torque, the method further includes: Determine the target limit torque based on the battery limit torque, motor feedback torque, vehicle limit torque and rear axle protection torque; Comparing the target limit torque with the target speed regulation torque to obtain a torque comparison result; When the torque comparison result is that the target speed regulating torque is less than or equal to the target limit torque, the step of performing auxiliary braking control on the vehicle according to the target speed regulating torque is performed.

5. The method according to claim 1, characterized in that Before the step of determining the target speed difference according to the target braking speed and the current driving speed when the current braking state is the auxiliary braking state and the vehicle operating state parameters meet the constant speed braking condition, the step further includes: Get the gear resistance value corresponding to the current switch gear; Calculate the voltage according to the gear resistance value to obtain a current voltage signal; Convert the current voltage signal according to a preset conversion method to obtain a current analog value; When the current analog value is within the target analog value range, it is determined that the current braking state is a constant speed braking state.

6. The method according to claim 1, characterized in that Before the step of determining the target speed difference according to the target braking speed and the current driving speed when the current braking state is the auxiliary braking state and the vehicle operating state parameters meet the constant speed braking condition, the step further includes: Determine the current logical gear, vehicle speed and basic vehicle parameters according to the vehicle operating condition parameters; When the current logical gear is in the target logical gear, the vehicle speed is in the target speed range, and the basic parameters of the vehicle meet the auxiliary braking conditions, it is determined that the vehicle operating parameters meet the constant speed braking conditions.

7. The method according to any one of claims 1 to 6, characterized in that After the step of performing auxiliary braking control according to the target speed regulating torque, the method further includes: When a vehicle fault is detected and the fault level is a target level, a power-off request instruction is generated; The vehicle power-off process is executed according to the request power-off instruction.

8. An auxiliary brake control device, characterized in that: The device comprises: A processing module, used for determining a target speed difference according to a target braking speed and a current driving speed when the current braking state is a constant speed braking state and the vehicle operating condition parameters meet the constant speed braking condition; The processing module is further used to obtain a target speed regulating torque according to the target speed difference, the current vehicle load, the current vehicle slope and a preset mapping relationship; The braking module is used to perform auxiliary braking control according to the target speed regulation torque.

9. An auxiliary brake control 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 auxiliary brake control 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 auxiliary braking control method according to any one of claims 1 to 7 are implemented.

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