A vehicle ramp following stop anti-rolling and starting anti-rolling control method and system

Abstract

The present invention provides a vehicle ramp following stop anti-rollback and starting anti-rollback control method and system. The method includes: calculating the maximum braking pressure required during following stop according to vehicle parameters; when it is determined based on the current brake line pressure value of the vehicle and the maximum braking pressure that there is a risk of the vehicle rolling back on the ramp during decelerating following stop, the braking system starts to build pressure until the maximum braking pressure is reached, and then maintains the current maximum braking pressure to keep the vehicle stationary on the ramp. For the anti-rollback control of the vehicle during following stop on the ramp, the present invention only needs to compare the current brake line pressure of the vehicle with the maximum braking pressure to pre-judge whether there is a risk of the vehicle rolling back in advance. When there is a risk of rolling back, the braking system is made to start building pressure until the maximum braking pressure is reached, thereby realizing that the braking system intervenes in advance before rolling back occurs, and further solving the problem of the vehicle rolling back when following and stopping on the ramp in an autonomous vehicle, reducing the risk coefficient of the vehicle and improving the user's riding experience.

Description

Technical Field

[0001] The present invention relates to the field of automotive autonomous driving, and more particularly, to a vehicle ramp following stop anti-roll and start anti-roll control method and system. Background Art

[0002] An automotive autonomous driving system, also known as a driverless car or a computer-driven car, is an intelligent vehicle system that realizes driverless operation through an on-vehicle computer system. Autonomous driving vehicles rely on the collaborative cooperation of artificial intelligence, visual computing, radar, monitoring devices, and the global positioning system, enabling the computer to automatically and safely operate a motor vehicle without any active operation by a human. Autonomous driving vehicles are undoubtedly beneficial to society, drivers, and pedestrians. The accident rate of autonomous driving vehicles can be almost reduced to zero. Even if affected by the accident rate of other motor vehicles, the high growth rate of the market share of autonomous driving vehicles will steadily reduce the overall accident rate. The driving mode of autonomous driving vehicles can be more energy-efficient and environmentally friendly, thus reducing traffic congestion and air pollution.

[0003] However, when the existing autonomous driving system follows and stops and starts on a ramp, there is a phenomenon of vehicle rollback. The most common situation is that when following and stopping, the vehicle will roll back a certain distance before braking to a stop, and when starting, the vehicle will also roll back a certain distance before starting. This will undoubtedly increase the risk of collision with the vehicle behind, resulting in dangerous accidents, and at the same time, it will also give the driver a bad experience or even cause panic. Summary of the Invention

[0004] In view of the technical problems existing in the prior art, the present invention provides a vehicle ramp following stop anti-roll and start anti-roll control method and system, aiming to solve the technical problem that existing autonomous driving vehicles cannot prevent rollback when following, stopping, and starting on a ramp.

[0005] According to a first aspect of the present invention, there is provided a vehicle ramp following stop anti-roll control method, including:

[0006] Calculating the maximum braking pressure required by the autonomous driving system when following and stopping according to the vehicle parameters;

[0007] When it is determined based on the current braking pipeline pressure value of the vehicle and the maximum braking pressure that there is a risk of vehicle rollback on the ramp during the deceleration following and stopping process, the braking system starts to build pressure until it reaches the maximum braking pressure, and then maintains the current maximum braking pressure to keep the vehicle stationary on the ramp.

[0008] According to a second aspect of the present invention, there is provided a vehicle ramp start anti-roll control method, including:

[0009] Calculating the minimum engine torque required by the autonomous driving system when starting according to the vehicle parameters;

[0010] When it is determined that there is a risk of the vehicle rolling backward on a slope during the starting process based on the current engine torque value of the vehicle and the minimum engine torque, during the process of the powertrain system controlling the vehicle engine torque value to increase to the minimum engine torque, the braking system maintains the current brake line pressure value of the vehicle at the maximum braking pressure; when the vehicle engine torque value reaches the minimum engine torque, the braking system reduces the current brake line pressure value of the vehicle to release pressure.

[0011] According to a third aspect of the present invention, there is provided a vehicle ramp following stop anti-rollback control system, including:

[0012] A first control module, configured to calculate the maximum braking pressure required during the stop of the autonomous driving system according to vehicle parameters, and when it is determined that there is a risk of the vehicle rolling backward on a slope during the deceleration and stop process based on the current brake line pressure value of the vehicle and the maximum braking pressure, send a pressure building instruction to the braking system;

[0013] The braking system is configured to start building pressure according to the pressure building instruction until it reaches the maximum braking pressure, and then maintain the current maximum braking pressure to keep the vehicle stationary on the slope.

[0014] According to a fourth aspect of the present invention, there is provided a vehicle ramp starting anti-rollback control system, including:

[0015] A second control module, configured to calculate the minimum engine torque required during the start of the autonomous driving system according to vehicle parameters, and when it is determined that there is a risk of the vehicle rolling backward on a slope during the starting process based on the current engine torque value of the vehicle and the minimum engine torque, send a torque increasing instruction to the powertrain system;

[0016] The powertrain system is configured to control the vehicle engine torque value to increase to the minimum engine torque according to the torque increasing instruction;

[0017] The braking system is configured to maintain the current brake line pressure value of the vehicle at the maximum braking pressure during the process of the vehicle engine torque value increasing to the minimum engine torque; when the vehicle engine torque value reaches the minimum engine torque, reduce the current brake line pressure value of the vehicle to release pressure.

[0018] A vehicle ramp following stop anti-rolling control method and system provided by the present invention calculates the maximum braking pressure required when the automatic driving system stops following based on vehicle parameters. When it is determined that there is a risk of the vehicle rolling backward on a ramp during the decelerating following stop process based on the current braking pipeline pressure value and the maximum braking pressure of the vehicle, the braking system starts to build pressure until the maximum braking pressure is reached, and then maintains the current maximum braking pressure to keep the vehicle stationary on the ramp. For the anti-rolling control of the vehicle following and stopping on a ramp, the present invention only needs to pre-judge whether there is a risk of the vehicle rolling backward based on the current braking pipeline pressure and the maximum braking pressure of the vehicle during the decelerating following stop process. When there is a risk of rolling backward, the braking system starts to build pressure until the maximum braking pressure is reached, and then maintains the current maximum braking pressure to keep the vehicle stationary on the ramp, thereby realizing that the braking system intervenes in advance before the vehicle rolls backward, and fundamentally solving the problem of the vehicle rolling backward when following and stopping on a ramp for an autonomous driving vehicle, greatly reducing the risk factor of the autonomous driving vehicle and improving the user's riding experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a flowchart of a vehicle ramp following stop anti-rolling control method provided by an embodiment of the present invention;

[0020] Figure 2 is a curve relationship diagram of a vehicle ramp following stop anti-rolling control method provided by an embodiment of the present invention;

[0021] Figure 3 is a torque schematic diagram of a vehicle ramp following stop anti-rolling control method provided by an embodiment of the present invention;

[0022] Figure 4 is a flowchart of a vehicle ramp starting anti-rolling control method provided by an embodiment of the present invention;

[0023] Figure 5 is a curve relationship diagram of a vehicle ramp starting anti-rolling control method provided by an embodiment of the present invention;

[0024] Figure 6 is a structural diagram of a vehicle ramp following stop anti-rolling control system provided by an embodiment of the present invention;

[0025] Figure 7 is a structural diagram of a vehicle ramp starting anti-rolling control system provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The following further describes in detail the specific embodiments of the present invention in conjunction with the accompanying drawings and embodiments. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0027] Refer to Figure 1 , Figure 1It is a flowchart of a vehicle ramp following and anti-rolling control method provided by an embodiment of the present invention.

[0028] As Figure 1 shown, the vehicle ramp following and anti-rolling control method includes the following steps:

[0029] Step S10: Calculate the maximum braking pressure required when the autonomous driving system follows and stops according to the vehicle parameters;

[0030] It should be noted that the execution subject of the method in this embodiment can be a computer terminal device with data processing, network communication, and program running functions, such as an in-vehicle computer, an in-vehicle mobile phone, etc.; it can also be a server device with the same or similar functions. Among them, when the above vehicle ramp following and anti-rolling control method runs on the server-side device, there can be a data forwarder on the vehicle side to cooperate to complete the corresponding functions. This embodiment and the following embodiments will be described by taking an in-vehicle computer as an example.

[0031] It should be understood that before the autonomous driving system of the vehicle calculates the above maximum braking pressure, the autonomous driving system can first obtain the running state of the vehicle in front on the ramp. When the running state of the vehicle in front is a deceleration state, then obtain the running speed of the vehicle in front and the running speed of the current vehicle, compare the running speeds of the two vehicles. When the running speed of the vehicle in front is less than the running speed of the current vehicle, the autonomous driving system issues a deceleration instruction and simultaneously starts to calculate the maximum braking pressure required when the current vehicle follows and stops. Among them, the solutions for obtaining the running state of the vehicle in front and obtaining the running speed of the vehicle are relatively common existing methods and will not be described in detail here.

[0032] It can be understood that the above vehicle parameters can be vehicle parameters preset by the manufacturer before the vehicle leaves the factory, or can be read by the vehicle autonomous driving system during initialization and / or manually set by the staff. This embodiment does not limit this.

[0033] In a specific implementation, the autonomous driving system reads the vehicle parameters to calculate the maximum braking pressure required when the vehicle follows and stops.

[0034] Step S20: When it is determined based on the current braking pipeline pressure value of the vehicle and the maximum braking pressure that there is a risk of the vehicle rolling back on the ramp during the deceleration following and stopping process, the braking system starts to build pressure until it reaches the maximum braking pressure, and then maintains the current maximum braking pressure to keep the vehicle stationary on the ramp.

[0035] It should be understood that when it is determined that there is no risk of the vehicle rolling back on the slope during the deceleration and stop process, the automatic driving system continues to obtain the brake pipeline pressure of the vehicle at the next moment, and at the same time continues to determine whether there is a risk of the vehicle rolling back according to the current brake pipeline pressure value of the vehicle and the above maximum braking pressure, until it is judged that there is a risk of the vehicle rolling back, the braking system starts to quickly build pressure, or until the vehicle stops on the slope and there is no risk of the vehicle rolling back during this process, the automatic driving system does not participate in the process control of this stop.

[0036] Refer to Figure 2 , Figure 2 which is a curve relationship diagram of a vehicle ramp following and anti-rolling control method provided by an embodiment of the present invention.

[0037] In a specific implementation, during the ramp following and stop process of the automatic driving system, the vehicle speed V2 represents the speed of the vehicle without deceleration. At this time, the automatic driving system judges that the vehicle in front decelerates and sends a deceleration instruction to the braking system. After the braking system receives the deceleration instruction, the deceleration module starts to be activated. At this time, when the automatic driving system judges that there is a risk of the vehicle rolling back through the above brake pipeline pressure and the maximum braking pressure, the automatic driving system sends a pressure building instruction to the braking system, and the braking system quickly builds pressure. When the vehicle speed is reduced to V1, the brake pipeline pressure reaches the above maximum braking pressure. At this time, the risk of the vehicle rolling back is eliminated, and the braking system only needs to maintain the current maximum pressure during the process of decelerating from the vehicle speed V1 to 0. Among them, the slope of the brake pressure of the braking system increasing from 0 to the above maximum braking pressure can be adjusted according to the actual riding experience of the user. The greater the slope, the worse the riding experience of the user. The adjustment method can be manual parameter adjustment or automatic acquisition of environmental parameters for adjustment, which are relatively common existing methods and will not be elaborated here.

[0038] In the embodiment of the present invention, when the automatic driving vehicle follows and stops on the ramp, by comparing the brake pressure in the braking system of the vehicle with the calculated maximum braking pressure, it is determined whether there is a risk of the vehicle rolling back, so as to be able to predict in advance the risk of the vehicle rolling back, and then send a pressure building instruction to the braking system, so that the braking system intervenes in advance, thereby fundamentally solving the problem of the vehicle rolling back when the automatic driving vehicle follows and stops on the ramp, and further reducing the risk coefficient of the automatic driving vehicle and improving the riding experience of the user.

[0039] In a possible embodiment, the step of calculating the maximum braking pressure required for the automatic driving system to follow and stop according to the vehicle parameters includes:

[0040] Step S101: Obtain the longitudinal slope angle of the current road and read the vehicle parameters of the vehicle. The vehicle parameters include: caliper cylinder diameter, friction coefficient of the friction pair, effective braking radius, front axle load, rear axle load, and tire radius;

[0041] It should be noted that the longitudinal slope angle of the above road is the angle between the ramp where the vehicle is located and the horizontal plane, and the above longitudinal slope angle can be obtained through internal calculation of the braking system.

[0042] It can be understood that the vehicle's overall vehicle parameters include, but are not limited to: caliper cylinder diameter, friction coefficient of the friction pair, effective braking radius, front axle load, rear axle load, and tire radius.

[0043] In a specific implementation, the autonomous driving system obtains the longitudinal slope angle obtained through internal calculation of the braking system and reads the vehicle's overall vehicle parameters.

[0044] Step S102: Based on the caliper cylinder diameter, the friction coefficient of the friction pair, the effective braking radius, the front axle load, the rear axle load, the tire radius, and the longitudinal slope angle, calculate the minimum braking pressure required for the vehicle to stop on the ramp without rolling backward when the power system does not intervene;

[0045] It should be noted that the autonomous driving system calculates the above minimum braking pressure by combining the overall vehicle parameters and the slope value of the ramp, and estimates it according to the law of conservation of torque.

[0046] In a specific implementation, the autonomous driving system estimates the minimum braking pressure required for the vehicle to stop on the ramp without rolling backward when the power system does not intervene by combining the overall vehicle parameters and the slope value of the ramp according to the law of conservation of torque.

[0047] Step S103: Calculate the maximum braking pressure required when the autonomous driving system follows and stops according to the minimum braking pressure.

[0048] It should be noted that since the above minimum braking pressure is an approximate value obtained through estimation, in order to ensure that the vehicle does not roll backward completely, a magnification factor needs to be added to the above minimum braking pressure in actual applications. In order to reduce the noise generated by the braking system during braking and ensure good NVH (Noise, Vibration, Harshness) conditions, the above magnification system is generally set between 1 and 1.2.

[0049] In a specific implementation, the autonomous driving system magnifies the above minimum braking pressure by 1 to 1.2 times to obtain the above maximum braking pressure, thereby reducing the noise generated by the braking system and improving the user's driving experience while ensuring that the vehicle does not roll backward completely.

[0050] In a possible embodiment, calculating the minimum braking pressure required for the vehicle to stop on a ramp without rolling back when the power system is not involved, based on the caliper cylinder diameter, the friction coefficient of the friction pair, the effective braking radius, the front axle load, the rear axle load, the tire radius, and the longitudinal slope angle, includes:

[0051] P min =(m1 + m2)gsinθr / 2πμR·D 2 ;

[0052] where m1 is the front axle load; m2 is the rear axle load; r is the tire radius; θ is the longitudinal slope angle of the road, D is the caliper cylinder diameter, μ is the friction coefficient of the friction pair, and R is the effective braking radius.

[0053] It should be noted that the above calculation method of the minimum braking pressure is obtained by setting and ignoring the influence of the ground friction resistance according to the law of conservation of moment.

[0054] Referring to Figure 3 , Figure 3 which is a moment schematic diagram of a vehicle ramp following stop anti-roll control method provided by an embodiment of the present invention.

[0055] It can be understood that according to the law of conservation of moment, when ignoring the influence of the ground friction resistance, the total braking moment when the vehicle is stationary on the ramp should be equal to the component moment of the vehicle front and rear axle loads in the vehicle driving direction.

[0056] It should be understood that the calculation method of the above total braking moment is:

[0057] M1 = P min ·π·(D / 2) 2 ·μ·R·4·2;

[0058] where M1 is the total braking moment, P min is the braking pipeline pressure, D is the caliper cylinder diameter, μ is the friction coefficient of the friction pair, and R is the effective braking radius;

[0059] It should also be understood that the calculation method of the above component moment is:

[0060] M2 = m1g·sinθ·r + m2g·sinθ·r;

[0061] where M2 is the component moment of the front and rear axle loads, m1 is the front axle load; m2 is the rear axle load; r is the tire radius; θ is the longitudinal slope angle of the road;

[0062] Therefore, when ignoring the influence of the ground friction resistance, the minimum braking force required for the vehicle to stop on the ramp without rolling back when the power system is not involved can be calculated by the above method.

[0063] In a possible embodiment, the maximum braking pressure required when the autonomous driving system comes to a stop is calculated based on the minimum braking pressure, and the calculation method is as follows:

[0064] P max = k·P min ;

[0065] Where k is the amplification factor, and the value range is k ∈ (1, 1.2). When the coefficient K is less than or equal to 1, the vehicle may experience rolling backward. When the coefficient K is greater than or equal to 1.2, the noise generated by the braking system during braking results in poor NVH, greatly reducing the user's riding experience.

[0066] In a possible embodiment, the steps of determining the risk of the vehicle rolling backward on a slope during the deceleration and stop process based on the current brake pipeline pressure of the vehicle and the maximum braking pressure include:

[0067] Step S201: When the current brake pipeline pressure value of the vehicle is greater than or equal to the maximum braking pressure, there is no risk of the vehicle rolling backward on a slope during the deceleration and stop process;

[0068] Step S202: When the current brake pipeline pressure value of the vehicle is less than the maximum braking pressure, there is a risk of the vehicle rolling backward on a slope during the deceleration and stop process.

[0069] In a specific implementation, a status bit signal that can predict the risk of the vehicle rolling backward when decelerating and stopping on a slope can be defined to determine whether the vehicle has a risk of rolling backward. The above status bit signal can be the maximum braking pressure value set in advance as the warning value, and it is judged in real time whether the pressure value of the current brake pipeline of the vehicle is less than the above maximum braking pressure value. When the pressure value of the current brake pipeline is less than the above maximum braking pressure value, the current autonomous driving system issues a risk signal. When the pressure value of the current brake pipeline is not less than the above maximum braking pressure value, the current autonomous driving system issues a risk-free signal. The above status bit signal can be used to cooperate with other systems to improve the user experience.

[0070] The embodiment of the present invention provides a vehicle ramp start anti-roll control method, referring to Figure 4 , Figure 4 is a flowchart of a vehicle ramp start anti-roll control method provided by an embodiment of the present invention.

[0071] In this embodiment, the vehicle ramp start anti-roll control method includes the following steps:

[0072] Step S30: Calculate the minimum engine torque required when the autonomous driving system starts according to the vehicle parameters;

[0073] It should be noted that before the vehicle starts on a ramp, it can also determine whether the current environment meets the starting conditions. The above starting conditions can be that there are no other vehicles in front of the ramp, the vehicle in front of the ramp has started to move, etc. This embodiment does not limit this.

[0074] In a specific implementation, the autonomous driving system calculates the minimum engine torque required for the vehicle to start on a ramp by reading the vehicle's overall parameters.

[0075] Step S40: When it is determined that there is a risk of the vehicle rolling back on the ramp during the starting process based on the current engine torque value of the vehicle and the minimum engine torque, during the process of the power system controlling the vehicle's engine torque value to increase to the minimum engine torque, the braking system maintains the current brake pipeline pressure value of the vehicle at the maximum braking pressure; when the vehicle's engine torque value reaches the minimum engine torque, the braking system reduces the current brake pipeline pressure value of the vehicle to release the pressure.

[0076] Refer to Figure 5 , Figure 5 This is a curve relationship diagram of a vehicle ramp start anti-roll control method provided by an embodiment of the present invention.

[0077] In a specific implementation, during the ramp start process of the autonomous driving system, within the time period from 0 to t0, the engine torque value of the vehicle increases rapidly but does not reach the above-mentioned minimum engine torque. At this time, the autonomous driving system determines that there is a risk of the vehicle rolling back during the start based on the current engine torque value of the vehicle and the above-mentioned minimum engine torque. The autonomous driving system sends a pressure maintenance instruction to the braking system, and the braking system maintains the brake pipeline pressure at the above-mentioned maximum braking pressure without change. At the moment t0, the engine torque value reaches the above-mentioned minimum engine torque. At this time, the risk of the vehicle rolling back on the ramp is eliminated, and the braking system quickly releases the pressure by reducing the current brake pipeline pressure value of the vehicle, so as to ensure that the vehicle can start automatically quickly. At the moment t1, the brake pressure value has dropped to 0, and the subsequent start process of the vehicle is taken over by the power system.

[0078] In the embodiment of the present invention, when the autonomous driving vehicle starts on a ramp, by comparing the vehicle's engine torque value with the calculated minimum engine torque, it is determined whether there is a risk of the vehicle rolling back, so as to be able to predict in advance the risk of the vehicle rolling back during the start process, and then send a pressure maintenance instruction to the braking system, so that the braking system delays exiting the control and the power system intervenes in advance, thereby fundamentally solving the problem of the vehicle rolling back when the autonomous driving vehicle starts on a ramp, and further reducing the risk coefficient of the autonomous driving vehicle and improving the user's driving experience.

[0079] In a possible embodiment, the step of calculating the minimum engine torque required for the autonomous driving system to start according to the vehicle's overall parameters includes:

[0080] Step S301: Obtain the longitudinal slope angle of the current road, and read the vehicle parameters, which further include: vehicle mass, transmission ratio, final drive ratio, and mechanical efficiency of the driveline.

[0081] It should be noted that the longitudinal slope angle of the above road is the angle between the ramp where the vehicle is located and the horizontal plane, and the above longitudinal slope angle can be obtained through internal calculation of the braking system.

[0082] It can be understood that the vehicle parameters of the above vehicle include, but are not limited to: vehicle mass, transmission ratio, final drive ratio, and mechanical efficiency of the driveline.

[0083] In a specific implementation, the autonomous driving system obtains the longitudinal slope angle calculated internally by the braking system and reads the vehicle parameters of the vehicle.

[0084] Step S302: Calculate the minimum engine torque required for the autonomous driving system to start according to the vehicle mass, the transmission ratio, the final drive ratio, the mechanical efficiency of the driveline, and the longitudinal slope angle.

[0085] It should be noted that the calculation method of the above minimum engine torque is obtained by calculating according to the law of conservation of mechanics under the condition of ignoring the influence of air resistance and ground friction.

[0086] In a specific implementation, define a variable T tamin , T tamin represents the minimum engine torque required for the vehicle not to roll back on the ramp when the braking system is not involved. Assuming that the influence of air resistance and ground friction is ignored, according to the law of conservation of mechanics, the driving force should be equal to the component of gravity when the vehicle is stationary on the ramp. Therefore, the minimum engine torque T required for the autonomous driving system to start can be calculated according to the above vehicle mass, the above transmission ratio, the above final drive ratio, the above mechanical efficiency of the driveline, and the above longitudinal slope angle. tamin .

[0087] In a possible embodiment, the calculation method of the above minimum engine torque is:

[0088] T tamin = mg·sinθ·r / i g i0η T ;

[0089] Where, m is the vehicle mass, θ is the longitudinal slope angle of the road, r is the tire radius, i g is the transmission ratio, i0 is the final drive ratio, η T is the mechanical efficiency of the driveline.

[0090] It is understandable that, according to the conservation of mechanics, when the influence of air resistance and ground friction is set to be ignored, the driving force of the vehicle when it is stationary on a ramp should be equal to the component of gravity, that is:

[0091] mg·sinθ=T tamin i g i0η T / r;

[0092] Therefore, when the influence of air resistance and ground friction is ignored, the above minimum engine torque value can be calculated according to the above method.

[0093] In a possible embodiment, the step of determining that there is a risk of the vehicle slipping backward on a ramp when starting based on the current engine torque value of the vehicle and the minimum engine torque includes:

[0094] Step 401: When the current engine torque value of the vehicle is greater than or equal to the minimum engine torque, there is no risk of the vehicle slipping backward during the starting process;

[0095] Step 402: When the current engine torque value of the vehicle is less than the minimum engine torque, there is a risk of the vehicle slipping backward during the starting process.

[0096] In a specific implementation, a status bit signal that can predict the risk of the vehicle slipping backward during automatic starting on a ramp can be defined to determine whether there is a risk of the vehicle slipping backward when starting on a ramp. The above status bit signal can be to set the above minimum engine torque value as a warning value in advance. When the current engine torque value of the vehicle is less than the warning value, it means that there is a risk of the vehicle slipping backward on the ramp, and a slipping backward risk signal is sent. When the current engine torque value of the vehicle is not less than the warning value, it means that there is no risk of the vehicle slipping backward on the ramp, and a no slipping backward risk signal is sent. The above status bit signal can be used to cooperate with other systems to improve the user experience.

[0097] Please refer to Figure 6 , Figure 6 which is a structural diagram of a vehicle ramp following stop and anti-slip control system provided by an embodiment of the present invention. As Figure 6 shown, a vehicle ramp following stop and anti-slip control system includes a first control module 100 and a braking system 200, where:

[0098] The first control module 100 is used to calculate the maximum braking pressure required when the automatic driving system follows and stops according to the vehicle parameters, and when it is determined that there is a risk of the vehicle slipping backward on a ramp during the deceleration following stop based on the current brake line pressure value of the vehicle and the maximum braking pressure, send a pressure building instruction to the braking system;

[0099] The braking system 200 is configured to start building pressure according to the pressure building instruction until the maximum braking pressure is reached, and then maintain the current maximum braking pressure to keep the vehicle stationary on the slope.

[0100] It can be understood that the vehicle ramp following and anti-rolling control system provided by the embodiments of the present invention corresponds to the vehicle ramp following and anti-rolling control methods provided by the foregoing embodiments. The relevant technical features of the vehicle ramp following and anti-rolling control system can refer to the relevant features of the vehicle ramp following and anti-rolling control methods of the foregoing embodiments, and will not be elaborated herein.

[0101] Please refer to Figure 7 , Figure 7 which is a structural diagram of a vehicle ramp start anti-rolling control system provided by an embodiment of the present invention. As Figure 6 shown, a vehicle ramp start anti-rolling control system includes a second control module 300, a power system 400, and a braking system 500, wherein

[0102] The second control module 300 is configured to calculate the minimum engine torque required for the start of the autonomous driving system according to the vehicle parameters, and when it is determined that there is a risk of the vehicle rolling backward on the slope based on the current engine torque value of the vehicle and the minimum engine torque, send a torque increasing instruction to the power system;

[0103] The power system 400 is configured to control the engine torque value of the vehicle to increase to the minimum engine torque according to the torque increasing instruction;

[0104] The braking system 500 is configured to maintain the current brake line pressure value of the vehicle at the maximum braking pressure during the process of increasing the engine torque value of the vehicle to the minimum engine torque; when the engine torque value of the vehicle reaches the minimum engine torque, reduce the current brake line pressure value of the vehicle to release the pressure.

[0105] It can be understood that the vehicle ramp start anti-rolling control system provided by the embodiments of the present invention corresponds to the vehicle ramp start anti-rolling control methods provided by the foregoing embodiments. The relevant technical features of the vehicle ramp start anti-rolling control system can refer to the relevant features of the vehicle ramp start anti-rolling control methods of the foregoing embodiments, and will not be elaborated herein.

[0106] It should be noted that in the above embodiments, the descriptions of the respective embodiments have their own emphases. For the parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0107] Those skilled in the art will understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0108] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, as well as combinations of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing device to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing device generate means for implementing the functions specified in Figure 1 one or more of the processes Figure 1 or blocks or combinations of blocks.

[0109] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory produce a manufactured article including instruction means that implement the functions specified in Figure 1 one or more of the processes Figure 1 or blocks or combinations of blocks.

[0110] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are performed on the computer or other programmable device to produce a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in Figure 1 one or more of the processes Figure 1 or blocks or combinations of blocks.

[0111] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they learn the basic creative concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications that fall within the scope of the present invention.

[0112] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. A vehicle ramp following stop and anti-sliding control method, characterized in that, Including: Calculating the maximum braking pressure required when the autonomous driving system follows and stops according to the vehicle parameters; Wherein, obtaining the longitudinal slope angle of the current road and reading the vehicle parameters, the vehicle parameters including the caliper cylinder diameter, the friction coefficient of the friction pair, the effective braking radius, the front axle load, the rear axle load and the tire radius; Based on the caliper cylinder diameter, the friction coefficient of the friction pair, the effective braking radius, the front axle load, the rear axle load, the tire radius and the longitudinal slope angle, calculating the minimum braking pressure required for the vehicle to stop on the ramp without slipping when the power system is not involved; Calculating the maximum braking pressure required when the autonomous driving system follows and stops according to the minimum braking pressure; When it is determined based on the current vehicle braking pipeline pressure value and the maximum braking pressure that there is a risk of the vehicle slipping on the ramp during the deceleration and stop process, the braking system starts to build pressure until the maximum braking pressure is reached, and then maintains the current maximum braking pressure to keep the vehicle stationary on the ramp; Wherein, the step of determining that there is a risk of the vehicle slipping on the ramp during the deceleration and stop process based on the current vehicle braking pipeline pressure and the maximum braking pressure includes: When the current vehicle braking pipeline pressure value is greater than or equal to the maximum braking pressure, there is no risk of the vehicle slipping on the ramp during the deceleration and stop process; When the current vehicle braking pipeline pressure value is less than the maximum braking pressure, there is a risk of the vehicle slipping on the ramp during the deceleration and stop process.

2. The vehicle ramp following stop and anti-rolling control method according to claim 1, wherein The calculating the minimum braking pressure required for the vehicle to stop on the ramp without slipping when the power system is not involved based on the caliper cylinder diameter, the friction coefficient of the friction pair, the effective braking radius, the front axle load, the rear axle load, the tire radius and the longitudinal slope angle: P min = (m1 + m2)gsinθr / 2πμR·D 2 ; Wherein, m1 is the front axle load; m2 is the rear axle load; r is the tire radius; θ is the longitudinal slope angle of the road, D is the caliper cylinder diameter, μ is the friction coefficient of the friction pair, and R is the effective braking radius; Correspondingly, the calculating the maximum braking pressure required when the autonomous driving system follows and stops according to the minimum braking pressure: P max = k·P min ; Wherein, k is a magnification factor, and the value range is k ∈ (1, 1.2).

3. A vehicle ramp following stop and anti-slip control system, characterized in that, Including: A first control module, configured to calculate the maximum braking pressure required when the autonomous driving system follows and stops according to the vehicle parameters, and send a pressure building instruction to the braking system when it is determined based on the current vehicle braking pipeline pressure value and the maximum braking pressure that there is a risk of the vehicle slipping on the ramp during the deceleration and stop process; Wherein, obtaining the longitudinal slope angle of the current road and reading the vehicle parameters, the vehicle parameters including the caliper cylinder diameter, the friction coefficient of the friction pair, the effective braking radius, the front axle load, the rear axle load and the tire radius; Based on the caliper cylinder diameter, the friction coefficient of the friction pair, the effective braking radius, the front axle load, the rear axle load, the tire radius and the longitudinal slope angle, calculating the minimum braking pressure required for the vehicle to stop on the ramp without slipping when the power system is not involved; Calculating the maximum braking pressure required when the autonomous driving system follows and stops according to the minimum braking pressure; Wherein, the determining that there is a risk of the vehicle slipping on the ramp during the deceleration and stop process includes: When the current brake line pressure value of the vehicle is greater than or equal to the maximum braking pressure, there is no risk of the vehicle rolling backward on a slope during the deceleration and stop process; When the current brake line pressure value of the vehicle is less than the maximum braking pressure, there is a risk of the vehicle rolling backward on a slope during the deceleration and stop process; The braking system is used to start building pressure according to the pressure building instruction until the maximum braking pressure is reached, and then maintain the current maximum braking pressure to keep the vehicle stationary on a slope.

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