Auxiliary brake control method, device, equipment and storage medium

Abstract

The application discloses an auxiliary braking control method and device, equipment and storage medium, and relates to the technical field of vehicles. The auxiliary braking control method comprises the following steps: when a current braking state is a constant-speed braking state and vehicle working condition parameters meet constant-speed braking conditions, determining a target speed difference according to a target braking vehicle speed and a current driving speed; obtaining a target speed regulation torque according to the target speed difference, a current vehicle load, a current vehicle slope and a preset mapping relationship; and performing auxiliary braking control on the vehicle according to the target speed regulation torque. By adaptively adjusting different braking torques according to different loads and slopes, the braking torque gradually approaches 0 under the condition of reaching a set speed, the vehicle keeps constant speed, the braking effect can be continuously and effectively ensured without the operation of the driver, the auxiliary braking torque is adaptively adjusted, the auxiliary braking control method is adapted to full-slope and full-load working conditions, and the problem that the auxiliary braking torque cannot be adjusted when the auxiliary braking torque is too large or too small is avoided.

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-powered vehicles achieve auxiliary braking and deceleration through a retarder or in-cylinder brake. New energy vehicles, however, lack an engine structure and instead generate negative torque deceleration and braking through the reverse action of the motor. A switch allows the driver to select the auxiliary braking mode, or even different levels of auxiliary braking and deceleration. However, under varying loads and slopes, too little torque can lead to insufficient deceleration, necessitating the use of the brakes. Excessive torque can lead to a sharp deceleration, necessitating the use of the accelerator for acceleration. Even with timely differentiation between multiple levels of auxiliary braking, this still fails to adapt to full-slope, full-load conditions, requiring driver assistance and creating inconvenience. Therefore, addressing the inability of existing auxiliary braking control methods to adapt to full-slope, full-load conditions has become a pressing issue. 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 working conditions.

[0004] To achieve the above objectives, the present application proposes an auxiliary braking control method, which includes:

[0005] 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;

[0006] Obtaining a target speed regulation torque according to the target speed difference, the current vehicle load, the current vehicle slope, and a preset mapping relationship;

[0007] Auxiliary braking control is performed on the vehicle according to the target speed regulation torque.

[0008] In one embodiment, when the current braking state is a constant speed braking state and the vehicle operating condition parameters meet the constant speed braking condition, the step of determining the target speed difference based on the target braking speed and the current driving speed includes:

[0009] 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;

[0010] determining a corresponding updated braking vehicle speed according to the brake pedal signal;

[0011] adjusting the preset braking speed according to the updated braking speed to obtain a target braking speed;

[0012] A target speed difference is determined according to the target braking vehicle speed and the current traveling speed.

[0013] In one embodiment, the step of obtaining the target speed regulation torque according to the target speed difference, the current vehicle load, the current vehicle slope, and a preset mapping relationship includes:

[0014] determining a corresponding target speed difference according to the target speed difference;

[0015] Determine the target deceleration value and the target adjustment parameter value according to the current vehicle load, the current vehicle slope and a preset mapping relationship;

[0016] A target speed regulation torque is obtained according to the target speed difference, the target deceleration value, and the target regulation parameter value.

[0017] In one embodiment, before the step of performing auxiliary braking control according to the target speed regulation torque, the method further includes:

[0018] Determine the target torque limit based on the battery torque limit, motor feedback torque, vehicle torque limit, and rear axle protection torque;

[0019] Comparing the target limit torque with the target speed regulation torque to obtain a torque comparison result;

[0020] When the torque comparison result shows 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.

[0021] In one embodiment, before the step of determining the target speed difference based on 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:

[0022] Get the gear resistance value corresponding to the current switch gear;

[0023] Perform voltage calculation according to the gear resistance value to obtain a current voltage signal;

[0024] Convert the current voltage signal according to a preset conversion method to obtain a current analog value;

[0025] 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.

[0026] In one embodiment, before the step of determining the target speed difference based on 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:

[0027] determine a current logical gear, a vehicle running speed and vehicle basic parameters according to vehicle working condition parameters;

[0028] determine that the vehicle working condition parameters meet the constant-speed braking condition when the current logical gear is in a target logical gear, the vehicle running speed is in a target speed range and the vehicle basic parameters meet auxiliary braking conditions.

[0029] In an embodiment, the step of performing auxiliary braking control according to the target speed regulation torque further comprises:

[0030] generate a request power-off instruction when a vehicle fault is detected and the fault level is a target level;

[0031] perform a vehicle power-off process according to the request power-off instruction.

[0032] In addition, to achieve the above object, the application further provides an auxiliary braking control device, which comprises:

[0033] a processing module configured to determine a target speed difference according to a target braking speed and a current running speed when a current braking state is a constant-speed braking state and vehicle working condition parameters meet constant-speed braking conditions;

[0034] the processing module is further configured to obtain a target speed regulation torque according to the target speed difference, a current vehicle load, a current vehicle slope and a preset mapping relationship;

[0035] a braking module configured to perform auxiliary braking control according to the target speed regulation torque.

[0036] In addition, to achieve the above object, the application further provides an auxiliary braking control device, which comprises 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 as described above.

[0037] In addition, to achieve the above object, the application further provides a storage medium, which is a computer readable storage medium, and the storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the auxiliary braking control method as described above.

[0038] In addition, to achieve the above object, the application further provides a computer program product, which comprises a computer program, and the computer program is executed by a processor to implement the steps of the auxiliary braking control method as described above.

[0039] This application determines a target speed difference based on 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 a target speed regulation torque based on 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 based on the target speed regulation torque. By adaptively adjusting different braking torques according to different load slopes, the braking torque gradually approaches 0 when the set vehicle speed is reached, maintaining the vehicle constant speed. The braking effect is continuously effective without the need for driver operation, and the adaptive adjustment of the auxiliary braking torque enables the auxiliary braking control method to adapt to all 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

[0040] 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.

[0041] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0042] Figure 1 A flowchart of the first embodiment of the auxiliary braking control method of the present application is provided;

[0043] Figure 2 A schematic diagram of the switch detection principle provided in Example 1 of the auxiliary braking control method of this application;

[0044] Figure 3 A schematic diagram of constant speed auxiliary braking conditions provided in Example 1 of the auxiliary braking control method of this application;

[0045] Figure 4 A flowchart of the second embodiment of the auxiliary braking control method of the present application is provided;

[0046] Figure 5 A schematic diagram of a constant speed auxiliary braking control flow chart provided in Example 2 of the auxiliary braking control method of this application;

[0047] Figure 6 A schematic diagram of a simplified flow chart of the auxiliary braking control method provided in Example 1 of the present application;

[0048] 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;

[0049] Figure 8This is a 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.

[0050] The purpose, features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0051] It should be understood that the specific embodiments described herein are merely used to explain the technical solutions of the present application and are not intended to limit the present application.

[0052] 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.

[0053] 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 the preset mapping relationship; and the vehicle is auxiliary brake controlled according to the target speed regulation torque.

[0054] Fuel-powered vehicles achieve auxiliary braking and deceleration through a retarder or in-cylinder brake. New energy vehicles, however, lack an engine structure and instead generate negative torque deceleration and braking through the reverse action of the motor. A switch allows the driver to select the auxiliary braking mode, or even different levels of auxiliary braking and deceleration. However, under varying loads and slopes, too little torque can lead to insufficient deceleration, necessitating the use of the brakes. Excessive torque can lead to a sharp deceleration, necessitating the use of the accelerator for acceleration. Even with timely differentiation between multiple levels of auxiliary braking, this still fails to adapt to full-slope, full-load conditions, requiring driver assistance and creating inconvenience. Therefore, addressing the inability of existing auxiliary braking control methods to adapt to full-slope, full-load conditions has become a pressing issue.

[0055] This application determines a target speed difference based on 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 a target speed regulation torque based on 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 based on the target speed regulation torque. By adaptively adjusting different braking torques according to different load slopes, the braking torque gradually approaches 0 when the set vehicle speed is reached, maintaining the vehicle constant speed. The braking effect is continuously effective without the need for driver operation, and the adaptive adjustment of the auxiliary braking torque enables the auxiliary braking control method to adapt to all slope and full load conditions, avoiding the problem of the auxiliary braking torque being too large or too small and unable to be adjusted.

[0056] It should be noted that the execution subject of the embodiment can 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. The following takes the auxiliary brake control device as the execution subject, for example, the vehicle control unit, to illustrate the embodiment and the following embodiments.

[0057] Based on this, the application provides an auxiliary brake control method, which refers to Figure 1 , Figure 1 The flowchart of the first embodiment of the auxiliary brake control method of the application is shown in the figure.

[0058] In the embodiment, the auxiliary brake control method includes steps S10-S30:

[0059] Step S10, when the current braking state is a constant speed braking state and the vehicle working condition parameters meet the constant speed braking condition, determining a target speed difference according to a target braking vehicle speed and a current driving speed;

[0060] It should be noted that the embodiment can set a constant vehicle speed according to the driving operation switch, so as to increase the range of the auxiliary brake power recovery at a fixed speed, and the auxiliary brake process does not need to be operated by the driver. The brake or throttle is self-adaptive, only needs to be operated when the driver needs to adjust the constant speed, which is convenient for driving experience, and avoids the problems of brake overheating caused by frequent brake operation, and auxiliary brake torque being too large or too small to adjust.

[0061] It can be understood that the current braking state includes a constant speed braking state and a multi-gear braking state, the constant speed braking state refers to the state of the vehicle starting the constant speed auxiliary brake, the multi-gear braking state refers to the state of the vehicle starting the multi-gear auxiliary brake, the vehicle working condition parameters include the vehicle speed, the current gearbox gear, the ABS state, the motor speed, the battery state, the current load mode, etc., the constant speed braking condition refers to the pre-set condition for starting the constant speed auxiliary brake, the constant speed braking condition includes the auxiliary brake condition, the target braking vehicle speed refers to the speed maintained by controlling the vehicle constant speed brake, the current driving speed refers to the current vehicle driving speed, and the target speed difference refers to the difference between the current driving speed and the target braking vehicle speed.

[0062] In a specific implementation, when the current braking state is the state of the vehicle starting the constant speed auxiliary brake and the vehicle working condition parameters meet the pre-set condition for starting the constant speed auxiliary brake, it indicates that the vehicle control unit judges that the constant speed auxiliary brake state is valid, starts the constant speed auxiliary brake control, and then calculates the difference between the speed maintained by controlling the vehicle constant speed brake and the current vehicle driving speed to obtain the target speed difference.

[0063] In a feasible implementation, steps S10 can include steps A11-A14 before:

[0064] Step A11, obtaining the gear resistance value corresponding to the current switch gear;

[0065] 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.

[0066] 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 based on the resistance value of the gear corresponding to the multi-gear switch.

[0067] Step A12, performing voltage calculation according to the gear resistance value to obtain a current voltage signal;

[0068] 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.

[0069] Step A13, converting the current voltage signal according to a preset conversion method to obtain a current analog value;

[0070] It is understood that the preset conversion mode refers to an analog-to-digital conversion (AD) mode, and the current analog value refers to a digital value after AD conversion.

[0071] 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.

[0072] Step A14: When the current analog value is within the target analog value range, determine that the current braking state is a constant speed braking state.

[0073] 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.

[0074] In a specific implementation, the digital value corresponding to the current voltage signal after AD conversion is compared with the analog range corresponding to when the constant speed auxiliary braking is valid. When the digital value corresponding to the current voltage signal after AD conversion is within the analog range corresponding to when the constant speed auxiliary braking is valid, it indicates that the current braking state is a constant speed braking state.

[0075] 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 the 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 to 1 gear, it is the constant speed auxiliary braking gear, and the multi-speed energy recovery gear is OFF. When it is turned to 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 5 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 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.

[0076] Table 1:

[0077]

[0078] In a feasible implementation manner, step S10 may include steps B11 to B12:

[0079] Step B11, determining the current logical gear, vehicle speed, and basic vehicle parameters based on the vehicle operating condition parameters;

[0080] 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 downhill status and brake pedal signal status, etc.

[0081] In the specific implementation, the vehicle's driving logic gear, current vehicle speed, accelerator pedal signal status, constant speed downhill status, and brake pedal signal status are determined based on parameters such as vehicle speed, current transmission gear, ABS status, motor speed, battery status, and current load mode.

[0082] 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, determining that the vehicle operating parameters meet the constant speed braking conditions.

[0083] 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.

[0084] In a specific implementation, when the current logical gear is in D, the current vehicle speed is in a vehicle speed range for determining whether the constant speed braking condition is met, and the throttle pedal signal state, the constant speed downhill state, and the brake pedal signal state all meet the conditions for starting the constant speed auxiliary braking, it is determined that the vehicle working condition parameter meets the constant speed braking condition.

[0085] It should be noted that, as shown in Figure 3 The constant speed auxiliary braking belongs to part of the drive control and energy recovery function, and needs to meet the relevant conditions to be started, otherwise there is a conflict or failure of other functions. The following conditions need to be met: the current logical gear is D (N / R is not necessary to start, otherwise there is a conflict of drive function when the gear is N / R); V1≥vehicle speed≥V2km / h (it is not necessary to have constant speed auxiliary braking in high speed, and the constant speed auxiliary braking will cause the vehicle to quickly reduce to 0 in low speed, which is not conducive to the function implementation); the throttle pedal signal is invalid (stepping on the accelerator is positive driving acceleration); the constant speed downhill switch is valid; unlimited power, limping, and power-off request (the vehicle has a speed limit and power limit request, and the power-off fault needs to be prioritized to limit the vehicle to ensure safety); the vehicle is in a driving READY high voltage state (high voltage state is a prerequisite for driving function, and high voltage is required to start); the SOC of the BMS is less than or equal to the high SOC setting value (when the SOC is high, the battery can allow a small recharge power to avoid overcharging); there is no ABS communication fault and the ABS is in an inactive state; the vehicle has not entered the cruise (the cruise function is prioritized); the stepped auxiliary braking switch and the auxiliary braking switch are invalid (to avoid braking function conflict); the brake pedal signal is invalid (the driver drives the braking behavior operation, and the driving braking demand is prioritized); when the above conditions are met at the same time, the vehicle controller judges that the constant speed auxiliary braking state is valid, and starts to enter the constant speed auxiliary braking control.

[0086] It should be noted that the vehicle controller detects the auxiliary braking switch, meets the constant speed auxiliary braking condition, and sends a related message signal to light up the instrument, because the function belongs to the energy recovery braking function, and needs to light up the brake light through the signal to remind pedestrians and vehicles.

[0087] Step S20, obtaining a target speed regulation torque according to the target speed difference, the current vehicle load, the current vehicle slope, and a preset mapping relationship;

[0088] 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 size of the current vehicle, the preset mapping relationship refers to the mapping relationship of different range loads, different range slopes, deceleration values, and PID adjustment parameter values, and the target speed regulation torque refers to the torque size required for adjusting the speed.

[0089] 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.

[0090] Step S30 : performing auxiliary braking control on the vehicle according to the target speed regulation torque.

[0091] 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.

[0092] In a feasible implementation manner, step S30 may include steps A31 to A33:

[0093] 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;

[0094] It can be understood that the battery limit torque refers to the torque limit corresponding to the battery's allowable peak charging power, the motor feedback torque refers to the motor's allowable feedback torque, the rear axle protection torque refers to the rear axle protection reverse drag torque, the vehicle limit torque refers to the vehicle's maximum torque parameter limit, and the target limit torque refers to the maximum auxiliary braking protection torque size.

[0095] In specific implementation, the minimum value among the torque limit corresponding to the battery's allowable charging peak power, the motor's allowable feedback torque, the rear axle protection reverse torque, and the vehicle's maximum torque parameter limit is taken as the protection torque for maximum auxiliary braking, that is, the target limit torque.

[0096] Step A32, comparing the target limit torque with the target speed regulation torque to obtain a torque comparison result;

[0097] 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.

[0098] In specific implementation, in order to ensure the safety of the entire 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 maximum auxiliary braking protection torque, and finally the torque comparison result is obtained.

[0099] Step A33 , when the torque comparison result shows 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.

[0100] In a specific implementation, when the torque comparison result shows 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.

[0101] In a feasible implementation manner, step S30 may include steps B31 and B32:

[0102] Step B31, when a vehicle fault is detected and the fault level is the target level, generating a power-off request instruction;

[0103] 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.

[0104] In specific implementations, if a serious fault is detected or other critical systems (such as BMS, motor controller, etc.) request power-off, the power-off process will be executed first.

[0105] Step B32: executing the vehicle power-off process according to the power-off request instruction.

[0106] In a specific implementation, the vehicle is controlled to execute a vehicle power-off process according to a request for controlling vehicle power-off, so as to ensure the safety of the vehicle.

[0107] It should be noted that the vehicle controller serves as a constant speed auxiliary braking control unit, taking into account the safety protection of the entire vehicle. When the constant speed auxiliary braking function is turned on, it is also necessary to detect the battery's allowable charging peak power (converted into torque limit), the motor's allowable feedback torque, the rear axle protection reverse torque, and the vehicle's maximum torque parameter limit, and take the smaller one as the maximum auxiliary braking torque protection; at the same time, it detects 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; detects the status of EBS, ESC, and ABS and responds 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.

[0108] This embodiment determines a target speed difference based on the target braking speed and the current driving speed when the current braking state is constant speed braking and the vehicle operating parameters meet the constant speed braking conditions; derives a target speed regulation torque based on 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 based on the target speed regulation torque. By adaptively adjusting the braking torque according to different load and slope conditions, the braking torque gradually approaches 0 when the set vehicle speed is reached, maintaining the vehicle's constant speed. This ensures continuous and effective braking without driver intervention. The adaptive adjustment of the auxiliary braking torque enables the auxiliary braking control method to adapt to all slope and load conditions, avoiding the problem of the auxiliary braking torque being too large or too small and unable to adjust.

[0109] 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 embodiment 1 can be referred to the above introduction and will not be described in detail later. Figure 4 , step S10 in the auxiliary braking control method includes steps S11 to S14:

[0110] 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;

[0111] It can be understood that the brake pedal signal refers to the signal used by the vehicle control system to detect the extent to which the driver presses the brake pedal.

[0112] 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 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.

[0113] Step S12, determining a corresponding updated braking vehicle speed according to the brake pedal signal;

[0114] 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.

[0115] In a specific implementation, when a brake pedal signal or an accelerator pedal signal is detected, it indicates that the driver wants to adjust the constant target vehicle speed, and then the vehicle speed corresponding to 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.

[0116] Step S13, adjusting the preset braking speed according to the updated braking speed to obtain a target braking speed;

[0117] It can be understood that the preset braking speed refers to the constant speed assist braking target speed in the initial state (taken as 0 for example in this embodiment), and the target braking speed refers to the updated constant speed assist braking target speed.

[0118] In a specific implementation, the constant speed assist braking target vehicle speed in the initial state is adjusted according to the constant speed assist braking vehicle speed that needs to be updated to obtain an updated constant speed assist braking target vehicle speed, ie, the target braking vehicle speed.

[0119] Step S14: determining a target speed difference according to the target braking speed and the current driving speed.

[0120] It can be understood that the target speed difference is obtained by calculating the difference between the speed maintained by controlling the constant speed braking of the vehicle and the current speed of the vehicle.

[0121] 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 speed setting speed; when the constant speed assist braking state is invalid, the constant downhill speed setting speed is maintained; after power off, the constant downhill speed setting speed defaults to 0.

[0122] In a feasible implementation, step S20 may further include steps S21 to S23:

[0123] Step S21, determining a corresponding target speed difference according to the target speed difference;

[0124] It can be understood that the target speed difference refers to the vehicle motor speed difference corresponding to the target speed difference.

[0125] 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.

[0126] 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;

[0127] 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.

[0128] 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.

[0129] Step S23: obtaining a target speed regulation torque according to the target speed difference, the target deceleration value, and the target regulation parameter value.

[0130] 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.

[0131] It should be noted that if Figure 5 As shown in the figure, constant speed downhill control allows the driver to drive the vehicle at a pre-set speed without pressing the accelerator or brake pedal. The VCU detects that the vehicle state meets the constant speed auxiliary braking conditions, records the current speed as the constant speed downhill preset speed, and enters the constant speed downhill function. When 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 the current speed is less than or equal to the constant target speed, the VCU requests a torque of 0. Constant speed auxiliary braking requires real-time detection of the difference between the current vehicle speed and the constant target speed as input, and selects different adjustment deceleration curves based on the current load and slope, converting the speed difference into a speed difference. As shown in Table 2, different load ranges and different slope ranges are set through a three-dimensional table lookup method, and the corresponding deceleration value is found as the slope of the torque change. The adapted torque change step is found, and the torque is calculated from the speed difference by looking up the corresponding PID adjustment parameter value. 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 intelligently and smoothly adjusted to the target speed in a torque control manner according to different loads and slopes.

[0132] Table 2:

[0133]

[0134] This embodiment determines a corresponding target speed difference based on the target speed difference; determines a target deceleration value and a target adjustment parameter value based on the current vehicle load, the current vehicle slope, and a preset mapping relationship; and obtains a target speed adjustment torque based on the target speed difference, the target deceleration value, and the target adjustment parameter value. This improves the accuracy of calculating the torque required for speed adjustment.

[0135] This embodiment monitors the brake pedal signal when the current braking state is constant speed braking and the vehicle operating parameters meet the constant speed braking conditions; determines a corresponding updated braking speed based on the brake pedal signal; adjusts the preset braking speed based on the updated braking speed to obtain a target braking speed; and determines a target speed difference based on the target braking speed and the current driving speed. Through this approach, constant speed auxiliary braking is activated, adaptively adjusting the deceleration and torque change rate based on load and slope, and gradually and smoothly adjusting from the current speed to the target speed without driver input. This avoids issues such as excessive or insufficient auxiliary braking torque that cannot be adjusted, as well as overheating caused by frequent braking, and improves the driving experience.

[0136] For example, in order to help understand the implementation process of the auxiliary braking control method obtained by combining this embodiment with the above embodiment 1, please refer to Figure 6 , Figure 6 This paper provides a simplified flowchart of an auxiliary braking control method. Specifically, the vehicle key is turned to high pressure, the forward gear is engaged in D, the accelerator is pressed to a certain speed, the multi-stage auxiliary brake switch is in first gear, the accelerator and brake are released, and when the constant speed auxiliary braking conditions are met, constant speed auxiliary braking control is initiated. The auxiliary braking torque is calculated based on the current and target speeds, load, and slope, and the MCU is requested to execute the auxiliary braking torque. The motor then adjusts the vehicle speed accordingly. The method begins with the following steps: start - engage high pressure - engage D gear - press the accelerator / brake to the appropriate speed - no accelerator / brake - constant speed auxiliary braking conditions are met - calculate the auxiliary braking torque and request it to the MCU - the motor executes the torque (if any conditions are not met - end) - end.

[0137] 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 scope of protection of the present application.

[0138] This application also provides an auxiliary brake control device, please refer to Figure 7 , the auxiliary brake control device includes:

[0139] The processing module 10 is configured to determine a target speed difference based on 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;

[0140] The processing module 10 is further configured 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;

[0141] The braking module 20 is configured to perform auxiliary braking control according to the target speed regulation torque.

[0142] Optionally, the processing module 10 is further configured to:

[0143] 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;

[0144] determining a corresponding updated braking vehicle speed according to the brake pedal signal;

[0145] adjusting the preset braking speed according to the updated braking speed to obtain a target braking speed;

[0146] A target speed difference is determined according to the target braking vehicle speed and the current traveling speed.

[0147] Optionally, the processing module 10 is further configured to:

[0148] determining a corresponding target speed difference according to the target speed difference;

[0149] Determine the target deceleration value and the target adjustment parameter value according to the current vehicle load, the current vehicle slope and a preset mapping relationship;

[0150] A target speed regulation torque is obtained according to the target speed difference, the target deceleration value, and the target regulation parameter value.

[0151] Optionally, the braking module 20 is further configured to:

[0152] Determine the target torque limit based on the battery torque limit, motor feedback torque, vehicle torque limit, and rear axle protection torque;

[0153] Comparing the target limit torque with the target speed regulation torque to obtain a torque comparison result;

[0154] When the torque comparison result shows 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.

[0155] Optionally, the processing module 10 is further configured to:

[0156] Get the gear resistance value corresponding to the current switch gear;

[0157] Perform voltage calculation according to the gear resistance value to obtain a current voltage signal;

[0158] Convert the current voltage signal according to a preset conversion method to obtain a current analog value;

[0159] 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.

[0160] Optionally, the processing module 10 is further configured to:

[0161] Determine the current logical gear, vehicle speed and basic vehicle parameters based on the vehicle operating condition parameters;

[0162] When the current logical gear is in the target logical gear, the vehicle speed is in the target speed range, and the basic vehicle parameters meet the auxiliary braking conditions, it is determined that the vehicle operating condition parameters meet the constant speed braking conditions.

[0163] Optionally, the braking module 20 is further configured to:

[0164] When a vehicle fault is detected and the fault level is a target level, a power-off request instruction is generated;

[0165] The vehicle power-off process is executed according to the power-off request instruction.

[0166] The auxiliary brake control device provided in this application, utilizing the auxiliary brake control method of the aforementioned embodiment, can resolve the technical issue of existing auxiliary brake control methods being unable to adapt to full-slope, full-load operating conditions. Compared to the prior art, the beneficial effects of the auxiliary brake control device provided in this application are the same as those of the auxiliary brake control method provided in the aforementioned embodiment. Other technical features of the auxiliary brake control device are the same as those disclosed in the aforementioned embodiment and are not further elaborated here.

[0167] The present application provides an auxiliary braking control device, which includes: at least one processor; and a memory 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.

[0168] Reference below Figure 8 , which shows a schematic structural diagram of an auxiliary brake control device suitable for implementing an 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), and in-vehicle terminals (e.g., in-vehicle navigation terminals), as well as fixed terminals such as digital TVs and desktop computers. Figure 8 The auxiliary brake control device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0169] like Figure 8As shown, the auxiliary brake control device can include a processing device 1001 (e.g., a central processing unit, a graphics processing unit, etc.) that can perform various appropriate actions and processes according to programs stored in a read only memory (ROM) 1002 or programs loaded from a storage device 1003 into a random access memory (RAM) 1004. Various programs and data required for operation of the auxiliary brake control device are also stored in the RAM 1004. The processing device 1001, the ROM 1002, and the RAM 1004 are connected to each other by a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. In general, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; the 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 wirelessly or by wire with other devices to exchange data. Although the auxiliary brake control device having various systems is shown in the figure, it should be understood that all of the systems shown are not required to be implemented or possessed. More or fewer systems can be alternatively implemented or possessed.

[0170] In particular, the processes described above with reference to the flowcharts can be implemented as a computer software program according to embodiments of the present disclosure. For example, embodiments of the present disclosure include a computer program product comprising a computer program carried on a computer readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network by a communication device, or installed from the storage device 1003, or installed from the ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the methods of embodiments of the present disclosure are performed.

[0171] The auxiliary brake control device provided by the present disclosure adopts the auxiliary brake control method in the above-mentioned embodiments, and can solve the technical problem that the existing auxiliary brake control method cannot adapt to full-gradient full-load working conditions. Compared with the prior art, the auxiliary brake control device provided by the present disclosure has the same beneficial effects as the auxiliary brake control method provided by the above-mentioned embodiments, and other technical features in the auxiliary brake control device are the same as the features disclosed in the previous embodiment method, which will not be repeated here.

[0172] It should be understood that the various parts disclosed in this application can be implemented using 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.

[0173] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

[0174] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, a computer program) stored thereon, wherein the computer-readable program instructions are used to execute the auxiliary braking control method in the above-mentioned embodiment.

[0175] The computer-readable storage medium provided herein 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 thereof. More specific examples of computer-readable storage media may include, but are not limited to, an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including, but not limited to, wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0176] 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.

[0177] 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: 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 regulation 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 regulation torque.

[0178] 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 stand-alone 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 via 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).

[0179] The flow charts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present application. In this regard, each box in the flow chart or block diagram can represent a module, program segment or a part of code, and the module, program segment or a part of 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 box can also occur in a different order than that marked in the accompanying drawings. For example, two 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 box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented by a dedicated hardware-based system that performs the specified function or operation, or can be implemented by a combination of dedicated hardware and computer instructions.

[0180] The modules described in the embodiments of the present application may be implemented in software or hardware, wherein the name of a module does not necessarily limit the unit itself.

[0181] The computer-readable storage medium provided in this application stores computer-readable program instructions (i.e., a computer program) for executing the aforementioned auxiliary braking control method. This computer-readable storage medium can address the technical issue of existing auxiliary braking control methods being unable to adapt to full-grade, full-load conditions. Compared to the prior art, the beneficial effects of the computer-readable storage medium provided in this application are similar to those of the auxiliary braking control method provided in the aforementioned embodiments and are not further elaborated here.

[0182] The present application also provides a computer program product, comprising a computer program, which implements the steps of the auxiliary braking control method as described above when the computer program is executed by a processor.

[0183] The computer program product provided in this application can address the technical issue of existing auxiliary braking control methods being unable to adapt to full-slope, full-load operating conditions. Compared to the prior art, the beneficial effects of the computer program product provided in this application are the same as those of the auxiliary braking control methods provided in the aforementioned embodiments, and are not further elaborated here.

[0184] The above description is only part of the embodiments of the present application and does not limit the patent scope of the present application. All equivalent structural transformations made by using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect application 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 includes: 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 regulation torque according to the target speed difference, the current vehicle load, the current vehicle slope, and a preset mapping relationship; performing auxiliary braking control on the vehicle according to the target speed regulation torque; Wherein, when the current braking state is a constant speed braking state and the vehicle operating condition parameters meet the constant speed braking conditions, 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; determining a target speed difference according to the target braking speed and the current driving speed; The step of obtaining the target speed regulation 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 speed difference according to the target speed difference; Determining a target deceleration value and a target adjustment parameter value based on the current vehicle load, the current vehicle slope, and a preset mapping relationship, wherein the target deceleration value is the deceleration value corresponding to the current vehicle load and the current vehicle slope, and the target adjustment parameter value is the PID adjustment parameter value corresponding to the current vehicle load and the current vehicle slope; Obtaining a target speed regulation torque according to the target speed difference, the target deceleration value, and the target regulation parameter value; Before the step of performing auxiliary braking control on the vehicle according to the target speed regulation torque, the method further includes: Determine the target torque limit based on the battery torque limit, motor feedback torque, vehicle torque limit, 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 shows 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.

2. The method according to claim 1, wherein 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 a constant speed braking state and the vehicle operating state parameters meet the constant speed braking condition, the method further includes: Get the gear resistance value corresponding to the current switch gear; Perform voltage calculation 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.

3. The method according to any one of claims 1 to 2, characterized in that After the step of performing auxiliary braking control on the vehicle 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 power-off request instruction.

4. The method according to any one of claims 1 to 3, characterized in that The method is applied to an auxiliary brake control device, the device comprising: a processing module, configured to determine a target speed difference based on a target braking speed and a 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; The processing module is further configured 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; a braking module, configured to perform auxiliary braking control according to the target speed regulating torque; The processing module is further configured to monitor the brake pedal signal when the current braking state is a constant speed braking state and the vehicle operating condition parameters meet the constant speed braking conditions; 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; determining a target speed difference according to the target braking speed and the current driving speed; The processing module is further configured to determine a corresponding target rotation speed difference according to the target speed difference; Determining a target deceleration value and a target adjustment parameter value based on the current vehicle load, the current vehicle slope, and a preset mapping relationship, wherein the target deceleration value is the deceleration value corresponding to the current vehicle load and the current vehicle slope, and the target adjustment parameter value is the PID adjustment parameter value corresponding to the current vehicle load and the current vehicle slope; Obtaining a target speed regulation torque according to the target speed difference, the target deceleration value, and the target regulation parameter value; The brake module is further configured to determine a target torque limit based on the battery torque limit, the motor feedback torque, the vehicle torque limit, and the 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 shows 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. 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 3.

6. 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 brake control method according to any one of claims 1 to 3 are implemented.

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