Brake control method and device, vehicle and storage medium

Abstract

The invention discloses a brake control method and device, a vehicle and a storage medium, and the method comprises the steps: obtaining a VCU communication state, a VCU uploading vehicle speed and a wheel speed sensor uploading wheel speed through a brake controller under the condition that the vehicle is powered off at high voltage; judging whether the vehicle is powered off abnormally or not according to the VCU communication state, the vehicle speed uploaded by the VCU and the wheel speed uploaded by the wheel speed sensor; if not, starting a power-off automatic parking function, and controlling a brake controller to apply the maximum parking braking force; if yes, linear braking force is applied through a braking controller according to the mass of the vehicle and the vehicle speed during abnormal power-off. According to the method, the vehicle locking sideslip risk is reduced, and the braking safety coefficient is improved.

Description

Technical Field

[0001] This application relates to the technical field of vehicles, and in particular, to a braking control method, device, vehicle, and storage medium. Background Art

[0002] To reduce the driving intensity, an electronic parking brake system has been developed in the vehicle field nowadays. The power-off automatic parking function therein can control the vehicle parking brake system to work through the brake controller after the vehicle is powered off, so as to achieve vehicle parking.

[0003] However, if the vehicle experiences an abnormal power-off due to a power system failure during driving and at a relatively high vehicle speed, and the vehicle activates the power-off parking function, an unexpected braking force will be applied to the vehicle, which is likely to cause a rear-end collision with the following vehicle. If the parking force is too large at this time, the vehicle will skid, posing a great safety hazard. Summary of the Invention

[0004] The present invention provides a braking control method, device, vehicle, and storage medium, which can solve the problems of rear-end collision caused by abnormal power-off and activation of power-off parking in the prior art, and vehicle skidding caused by too large parking force. The technical solutions are as follows:

[0005] In a first aspect of the present invention, a braking control method is proposed. The method includes:

[0006] When the vehicle is under high-voltage power-off, obtain the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor through the brake controller;

[0007] Judge whether the vehicle has an abnormal power-off according to the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor;

[0008] If it is not an abnormal power-off, start the power-off automatic parking function and control the brake controller to apply the maximum parking braking force;

[0009] If it is an abnormal power-off, apply a linear braking force through the brake controller according to the mass of the vehicle and the vehicle speed at the time of abnormal power-off.

[0010] Optionally, the judging whether the vehicle has an abnormal power-off according to the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor includes:

[0011] If the VCU communication status is normal, the vehicle speed uploaded by the VCU is 0, and the wheel speed uploaded by the wheel speed sensor is 0, judge that the vehicle is not abnormally powered off;

[0012] If the VCU communication is lost, the vehicle speed uploaded by the VCU is not 0, or the wheel speed uploaded by the wheel speed sensor is not 0, judge that the vehicle is abnormally powered off.

[0013] Optionally, if it is abnormal power-off, according to the mass of the vehicle and the vehicle speed at the time of abnormal power-off, a linear braking force is applied through the brake controller, including:

[0014] Obtain the mass of the vehicle before power-off;

[0015] Read the vehicle speed at the time of abnormal power-off of the vehicle obtained by the wheel speed sensor;

[0016] Determine the deceleration of braking based on the vehicle speed at the time of abnormal power-off of the vehicle;

[0017] Determine the applied braking force according to the deceleration and the mass of the vehicle.

[0018] Optionally, the determining the deceleration of braking based on the vehicle speed at the time of abnormal power-off of the vehicle includes:

[0019] If the vehicle speed at the time of abnormal power-off of the vehicle is greater than or equal to the first vehicle speed threshold, the deceleration of braking is the first deceleration;

[0020] If the vehicle speed at the time of abnormal power-off of the vehicle is greater than or equal to the second vehicle speed threshold and less than the first vehicle speed threshold, the deceleration of braking is the second deceleration;

[0021] If the vehicle speed at the time of abnormal power-off of the vehicle is greater than or equal to the third vehicle speed threshold and less than the second vehicle speed threshold, the deceleration of braking is the third deceleration;

[0022] If the vehicle speed at the time of abnormal power-off of the vehicle is less than the third vehicle speed threshold, the maximum parking braking force is applied to the vehicle; wherein, the first vehicle speed threshold is greater than the second vehicle speed threshold; the second vehicle speed threshold is greater than the third vehicle speed threshold; the first deceleration is greater than the second deceleration; the second deceleration is greater than the third deceleration.

[0023] Optionally, the vehicle is equipped with a redundant power supply, and when the vehicle is abnormally powered off, the redundant power supply is used to distribute power to the brake controller of the vehicle.

[0024] Optionally, when the vehicle is abnormally powered off, the redundant power supply is used to control the brake signal lamp and the hazard warning flasher on the vehicle to turn on.

[0025] A second aspect of the present invention provides a braking control device, including:

[0026] An acquisition module, configured to obtain the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor through the brake controller when the vehicle is under high-voltage power-off;

[0027] A judgment module, configured to judge whether the vehicle has an abnormal power-off according to the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor;

[0028] A processing module, configured to, if it is not an abnormal power-off, start the power-off automatic parking function and control the brake controller to apply the maximum parking braking force; if it is an abnormal power-off, apply a linear braking force through the brake controller according to the mass of the vehicle and the vehicle speed at the time of abnormal power-off.

[0029] A third aspect of the present invention provides a vehicle, which includes a processor and a memory. At least one instruction or at least one program segment is stored in the memory, and the at least one instruction or at least one program segment is loaded and executed by the processor to implement the braking control method as described in the first aspect.

[0030] A fourth aspect of the present invention provides a computer-readable storage medium, in which at least one instruction or at least one program segment is stored, and the at least one instruction or at least one program segment is loaded and executed by a processor to implement the braking control method as described in the first aspect.

[0031] The embodiments of the present invention have the following beneficial effects:

[0032] In the embodiments of the present invention, when the vehicle has a high-voltage power-off, it is first judged whether it is an abnormal power-off. If it is an abnormal power-off, a linear braking force is applied according to the vehicle speed. Compared with the prior art, the risk of vehicle side slip and the risk of rear-end collision are reduced. Description of the Drawings

[0033] Figure 1 is a flowchart of a braking control method provided by an embodiment of the present invention;

[0034] Figure 2 is a schematic diagram of signal interaction of a brake controller in an embodiment of the present invention;

[0035] Figure 3 is a schematic diagram of vehicle abnormal power-off judgment in an embodiment of the present invention;

[0036] Figure 4 is an EMB circuit diagram in an embodiment of the present invention. Detailed Embodiments

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0038] Hereinafter, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present disclosure, unless otherwise stated, the meaning of "a plurality of" is two or more. Additionally, the use of "based on" or "in accordance with" implies openness and inclusivity, because a process, step, calculation, or other action "based on" or "in accordance with" one or more of the stated conditions or values may, in practice, be based on additional conditions or values beyond those stated.

[0039] An embodiment of the present invention provides a braking control method. Referring to Figure 1 and Figure 2 , the method includes the following steps:

[0040] Step 101: When the vehicle is under high-voltage power-on, obtain the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speeds uploaded by the wheel speed sensors through the braking controller.

[0041] Specifically, the braking controller receives the vehicle speed collected by the VCU from the transmission through the CAN bus, and receives the wheel speed sensor information uploaded by each wheel end through a hard wire or the CAN bus.

[0042] Step 102: Determine whether the vehicle has an abnormal power-off according to the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speeds uploaded by the wheel speed sensors.

[0043] Specifically, the VCU communication status refers to the communication status between the braking control system and the VCU. The vehicle power-off refers to the vehicle's high-voltage power cut-off.

[0044] In a possible implementation manner, the determining whether the vehicle has an abnormal power-off according to the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speeds uploaded by the wheel speed sensors includes:

[0045] Referring to Figure 3 , if the VCU communication status is normal, the vehicle speed uploaded by the VCU is 0, and the wheel speeds uploaded by the wheel speed sensors are 0, it is determined that the vehicle has a non-abnormal power-off, that is, a normal power-off.

[0046] If the VCU communication is lost, the vehicle speed uploaded by the VCU is not 0, or the wheel speeds uploaded by the wheel speed sensors are not 0, it is determined that the vehicle has an abnormal power-off.

[0047] Step 103: If it is not an abnormal power-off, start the power-off automatic parking function and control the braking controller to apply the maximum parking braking force; if it is an abnormal power-off, apply a linear braking force through the braking controller according to the mass of the vehicle and the vehicle speed at the time of abnormal power-off.

[0048] Specifically, the braking force applied by the brake can be the hydraulic pressure of the hydraulic system, the air pressure of the pneumatic braking system, or the braking torque of the EMB system. This embodiment does not make specific limitations on this.

[0049] In a possible implementation manner, if it is an abnormal power-off, according to the mass of the vehicle and the vehicle speed at the time of abnormal power-off, a linear braking force is applied through the brake controller, including:

[0050] Obtain the mass of the vehicle before power-off;

[0051] Read the vehicle speed at the time of abnormal power-off of the vehicle obtained by the wheel speed sensor;

[0052] Determine the deceleration of braking based on the vehicle speed at the time of abnormal power-off of the vehicle;

[0053] Determine the applied braking force according to the deceleration and the mass of the vehicle.

[0054] Specifically, the mass of the vehicle can be calculated and determined by the brake controller. The brake controller collects vehicle acceleration or deceleration information through the acceleration sensor to calculate the vehicle mass, and the vehicle speed at the time of abnormal power-off is obtained by the feedback of the wheel speed sensor. The brake controller applies a corresponding deceleration according to the vehicle speed at the time of abnormal power-off of the vehicle to avoid vehicle rear-end collisions. Finally, the braking force is determined according to the magnitude of the deceleration and the mass of the vehicle.

[0055] In a possible implementation manner, the determining the deceleration of braking based on the vehicle speed at the time of abnormal power-off of the vehicle includes:

[0056] If the vehicle speed at the time of abnormal power-off of the vehicle is greater than or equal to the first vehicle speed threshold, the deceleration of braking is the first deceleration;

[0057] If the vehicle speed at the time of abnormal power-off of the vehicle is greater than or equal to the second vehicle speed threshold and less than the first vehicle speed threshold, the deceleration of braking is the second deceleration;

[0058] If the vehicle speed at the time of abnormal power-off of the vehicle is greater than or equal to the third vehicle speed threshold and less than the second vehicle speed threshold, the deceleration of braking is the third deceleration;

[0059] If the vehicle speed at the time of abnormal power-off of the vehicle is less than the third vehicle speed threshold, the maximum parking braking force is applied to the vehicle; wherein, the first vehicle speed threshold is greater than the second vehicle speed threshold; the second vehicle speed threshold is greater than the third vehicle speed threshold; the first deceleration is greater than the second deceleration; the second deceleration is greater than the third deceleration.

[0060] Exemplarily, the first vehicle speed threshold can be set to 60 km / h, the second vehicle speed threshold can be set to 20 km / h, and the third vehicle speed threshold can be set to 7 km / h. The first deceleration is set to 5 m / s 2 , the second deceleration is set to 4 m / s 2 , and the third deceleration is set to 3 m / s 2 . Here, only the recommended values under normal control are used for illustration. The specific vehicle speed thresholds and deceleration values can be set by the implementer according to the vehicle operation scenario. If the vehicle has an intelligent connected vehicle system with vehicle-road cooperation or vehicle-vehicle cooperation, the deceleration value can be adjusted according to the road conditions and vehicle conditions to ensure driving safety. When the vehicle speed during abnormal power-off exceeds 60 km / h, compared with the vehicle speeds in other vehicle speed threshold ranges, the vehicle spacing corresponding to this vehicle speed is relatively large at this time, and a deceleration of 5 m / s can be applied 2 to stop the vehicle. When the vehicle speed during abnormal power-off is greater than or equal to 20 km / h and less than 60 km / h, compared with the previous situation, the vehicle spacing is relatively shorter, and a deceleration of 4 m / s can be applied 2 . When the vehicle speed during abnormal power-off is greater than or equal to 7 km / h and less than 20 km / h, compared with the previous two vehicle speeds, the vehicle is driving at a low speed, and a deceleration of 3 m / s can be applied 2 . In the above three cases, after determining the corresponding deceleration, refer to the axle load transfer value under this braking deceleration with a road adhesion coefficient of 0.7 for front and rear axle braking force distribution, apply the braking force, and at the same time, the vehicle can be transferred to a safe area by steering. Specifically, the brake controller calculates the braking torque required to be distributed to each wheel according to the deceleration requirement and the front and rear axle braking force distribution principle, and drives the electronic control braking system to apply the braking force to the front and rear axles, or applies the braking force to each wheel in the electro-mechanical braking system

[0061] When the vehicle speed during abnormal power-off is less than 7 km / h, the wheel speed sensor feedback of the vehicle information is not accurate enough at this time. Compared with the above situation, the vehicle is driving at an ultra-low speed, and the power-off parking logic can be adopted to apply the maximum parking braking force to stop the vehicle

[0062] In a possible implementation manner, the vehicle is equipped with a redundant power supply, and when the vehicle has an abnormal power-off, the redundant power supply supplies power to the brake controller of the vehicle

[0063] Specifically, as Figure 4As shown in the figure, where the dashed line represents the control power and the solid line represents the power supply. Here, only the vehicle with an EMB system configuration is used for illustration, and the system configuration of the vehicle is not limited in this embodiment. The voltage of the EMB system is 48V. To meet the requirement of 8 - 9 full - stroke brakings when the power supply fails, a 48V battery or a supercapacitor module is configured separately. On this basis, a 48V - to - 24V DC - DC converter is added to provide 24V power redundancy. When the 24V power supply of the vehicle fails, the redundant power supplies power to the brake controller to control the vehicle to brake according to the abnormal power - off logic, thus ensuring driving safety.

[0064] When the vehicle is powered off, the 24V control power is normal, and the vehicle control unit (VCU) and the brake controller are in the power - on and wake - up mode. After the vehicle has completed parking, the VCU and the brake controller can be powered off.

[0065] In a possible implementation, when the vehicle is abnormally powered off, the redundant power is used to control the brake lights and the hazard lights on the vehicle to turn on.

[0066] Specifically, the redundant power can also supply power to the vehicle control unit (VCU) and other control systems, such as for controlling the brake lights and the hazard lights, to ensure certain signal transmission and control functions, improving the safety of the vehicle.

[0067] In the embodiment of the present invention, by providing redundant power, when the vehicle has an abnormal power cut - off, power is supplied to the brake controller to ensure parking safety. By distinguishing normal power - off and abnormal power - off and implementing corresponding braking schemes, the vehicle locking and skidding caused by unexpected braking are avoided, and accidents are avoided to a certain extent. In the case of abnormal power - off, according to the vehicle speed, linear braking force is applied, thus reducing the risk of vehicle skidding. At the same time, the brake lights and the hazard lights are turned on to remind the following vehicle, reducing the risk of rear - end collision.

[0068] The embodiment of the present invention provides a braking control device, including:

[0069] An acquisition module, configured to obtain the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor through the brake controller when the vehicle is under high - voltage power - off;

[0070] A judgment module, configured to judge whether the vehicle is abnormally powered off according to the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor;

[0071] A processing module, configured to, if it is not abnormally powered off, start the power - off and automatic parking function and control the brake controller to apply the maximum parking braking force; if it is abnormally powered off, apply linear braking force through the brake controller according to the mass of the vehicle and the vehicle speed at the time of abnormal power - off.

[0072] An embodiment of the present invention provides a vehicle, which includes a processor and a memory. At least one instruction or at least one program segment is stored in the memory, and the at least one instruction or at least one program segment is loaded and executed by the processor to implement the braking control method as described in the embodiments of the present invention.

[0073] An embodiment of the present invention provides a computer-readable storage medium, in which at least one instruction or at least one program segment is stored, and the at least one instruction or at least one program segment is loaded and executed by a processor to implement the braking control method as described in the embodiments of the present invention.

[0074] As described above, the above is only a specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A braking control method, characterized in that, The method includes: When the vehicle is under high - voltage power - off, obtain the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor through the brake controller; Judge whether the vehicle has an abnormal power - off according to the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor; If it is not an abnormal power - off, start the power - off automatic parking function and control the brake controller to apply the maximum parking braking force; If it is an abnormal power - off, apply a linear braking force through the brake controller according to the mass of the vehicle and the vehicle speed at the time of abnormal power - off.

2. The braking control method according to claim 1, wherein The judging whether the vehicle has an abnormal power - off according to the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor includes: If the VCU communication status is normal, the vehicle speed uploaded by the VCU is 0, and the wheel speed uploaded by the wheel speed sensor is 0, judge that the vehicle is not abnormally powered off; If the VCU communication is lost, the vehicle speed uploaded by the VCU is not 0, or the wheel speed uploaded by the wheel speed sensor is not 0, judge that the vehicle is abnormally powered off.

3. The braking control method according to claim 1, characterized in that The applying a linear braking force through the brake controller according to the mass of the vehicle and the vehicle speed at the time of abnormal power - off when it is an abnormal power - off includes: Obtain the mass of the vehicle before power - off; Read the vehicle speed at the time of abnormal power - off of the vehicle obtained by the wheel speed sensor; Determine the deceleration of braking based on the vehicle speed at the time of abnormal power - off of the vehicle; Determine the applied braking force according to the deceleration and the mass of the vehicle.

4. The braking control method according to claim 3, characterized in that The determining the deceleration of braking based on the vehicle speed at the time of abnormal power - off of the vehicle includes: If the vehicle speed at the time of abnormal power - off of the vehicle is greater than or equal to the first vehicle - speed threshold, the deceleration of braking is the first deceleration; If the vehicle speed at the time of abnormal power - off of the vehicle is greater than or equal to the second vehicle - speed threshold and less than the first vehicle - speed threshold, the deceleration of braking is the second deceleration; If the vehicle speed at the time of abnormal power - off of the vehicle is greater than or equal to the third vehicle - speed threshold and less than the second vehicle - speed threshold, the deceleration of braking is the third deceleration; If the vehicle speed at the time of abnormal power - off of the vehicle is less than the third vehicle - speed threshold, then apply the maximum parking braking force to the vehicle; where the first vehicle - speed threshold is greater than the second vehicle - speed threshold; the second vehicle - speed threshold is greater than the third vehicle - speed threshold; the first deceleration is greater than the second deceleration; the second deceleration is greater than the third deceleration.

5. The braking control method according to claim 1, characterized in that, The vehicle is equipped with a redundant power supply. When the vehicle is abnormally powered off, the redundant power supply powers the brake controller of the vehicle.

6. The braking control method according to claim 5, wherein, When the vehicle is abnormally powered off, control the brake lights and hazard lights on the vehicle to turn on through the redundant power supply.

7. A braking control device, characterized in that, It includes: An acquisition module, used to obtain the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor through the brake controller when the vehicle is under high - voltage power - off; A judgment module, used to judge whether the vehicle has an abnormal power - off according to the VCU communication status, the vehicle speed uploaded by the VCU, and the wheel speed uploaded by the wheel speed sensor; A processing module, which is used to start the power-off automatic parking function and control the brake controller to apply the maximum parking braking force if it is not an abnormal power-off; if it is an abnormal power-off, a linear braking force is applied through the brake controller according to the mass of the vehicle and the vehicle speed at the time of abnormal power-off.

8. A vehicle, characterized in that, The vehicle includes a processor and a memory, and at least one instruction or at least one program segment is stored in the memory, and the at least one instruction or at least one program segment is loaded and executed by the processor to implement the braking control method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, At least one instruction or at least one program segment is stored in the storage medium, and the at least one instruction or at least one program segment is loaded and executed by a processor to implement the braking control method according to any one of claims 1-6.

Images