Longitudinal Control Method, Device, Electronic Device, and Storage Medium

Abstract

The present application discloses a longitudinal control method, device, electronic device, and storage medium. The method includes receiving an acceleration value instruction required by an upper-layer controller; calculating a torque value corresponding to the acceleration value required by the upper-layer controller according to a vehicle longitudinal dynamics model; when the torque value is a negative torque, determining whether the acceleration value is also negative; if it is a negative torque value and the acceleration value is negative, sending the acceleration value instruction required by the upper-layer controller to a vehicle braking system, where the vehicle braking system is configured to only receive negative acceleration instructions; if it is a negative torque value, the acceleration value is non-negative, and the negative torque value is within a preset range value, sending the calculated torque value to a vehicle drive system, where the vehicle drive system is configured to receive positive torque and negative torque within a preset range value. By means of the present application, the sense of jerk during driving is reduced, and the switching of the braking system for longitudinal control is made smoother.

Description

Technical Field

[0001] This application relates to the field of autonomous driving technology, and particularly to a longitudinal control method, device, electronic device, and storage medium. Background Art

[0002] Acceleration, braking, etc. belong to the underlying longitudinal control logic of autonomous driving.

[0003] In related technologies, a fixed coefficient or calibration method is usually adopted. However, the switching logic between their braking and driving depends only on whether the acceleration given by the upper controller is positive or negative. If it is negative, it is braking, and vice versa for driving. Therefore, this may cause frequent switching between braking and driving in some working conditions, resulting in a sense of jerk for the passengers and reducing the driving and riding experience. Summary of the Invention

[0004] Embodiments of this application provide a longitudinal control method, device, electronic device, and storage medium to optimize longitudinal control, make the driving and braking switching of longitudinal control smoother, and reduce the sense of jerk.

[0005] Embodiments of this application adopt the following technical solutions:

[0006] In a first aspect, an embodiment of this application provides a longitudinal control method, which includes:

[0007] Receiving an acceleration value command required by an upper controller;

[0008] Calculating a torque value corresponding to the acceleration value required by the upper controller according to a vehicle longitudinal dynamics model;

[0009] When the torque value is a negative torque, determining whether the acceleration value is also negative;

[0010] If it is a negative torque value and the acceleration value is negative, sending the acceleration value command required by the upper controller to a vehicle braking system, where the vehicle braking system is configured to only receive negative acceleration commands;

[0011] If it is a negative torque value, the acceleration value is non - negative, and the negative torque value is within a preset range value, sending the calculated torque value to a vehicle drive system, where the vehicle drive system is configured to receive positive torque and negative torque within the preset range value.

[0012] In a second aspect, an embodiment of this application further provides a longitudinal control device, which includes:

[0013] A receiving module, configured to receive an acceleration value command required by an upper controller;

[0014] A calculation module, configured to calculate a torque value corresponding to the acceleration value required by the upper-layer controller according to a vehicle longitudinal dynamics model;

[0015] A judgment module, configured to judge whether the acceleration value is also negative when the torque value is a negative torque;

[0016] A first execution module, configured to, if the torque value is a negative torque value and the acceleration value is negative, send an acceleration value instruction required by the upper-layer controller to a vehicle braking system, where the vehicle braking system is configured to only receive a negative acceleration instruction;

[0017] A second execution module, configured to, if the torque value is a negative torque value, the acceleration value is non-negative, and the negative torque value is within a preset range value, send the calculated torque value to a vehicle drive system, where the vehicle drive system is configured to receive a positive torque and a negative torque within the preset range value.

[0018] In a third aspect, an embodiment of the present application further provides an electronic device, including: a processor; and a memory arranged to store computer-executable instructions, where the executable instructions, when executed, cause the processor to execute the above method.

[0019] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, where the computer-readable storage medium stores one or more programs, and when the one or more programs are executed by an electronic device including a plurality of application programs, the electronic device is caused to execute the above method.

[0020] The above at least one technical solution adopted in the embodiment of the present application can achieve the following beneficial effects:

[0021] First, an acceleration value instruction required by the upper-layer controller is received, and then a torque value corresponding to the acceleration value required by the upper-layer controller is calculated according to the vehicle longitudinal dynamics model. Further, when the torque value is a negative torque, it is judged whether the acceleration value is also negative. For a negative torque value and a negative acceleration value, the acceleration value instruction required by the upper-layer controller is sent to the vehicle braking system; for a negative torque value, a non-negative acceleration value, and the negative torque value within a preset range value, the calculated torque value is sent to the vehicle drive system. From the perspective of vehicle longitudinal dynamics, by judging the acceleration value expected by the upper-layer controller, corresponding negative acceleration values or torque value instructions can be sent to the vehicle braking system or the drive system according to the expected acceleration. The sense of jerk during driving is reduced, and the switching of the longitudinal control braking system is made smoother. Description of the Drawings

[0022] The accompanying drawings described herein are used to provide a further understanding of the present application, and constitute a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application, and do not constitute an improper limitation of the present application. In the drawings:

[0023] Figure 1 is a schematic flow chart of a coefficient determination method in the related art;

[0024] Figure 2 is a schematic flow chart of a calibration method in the related art;

[0025] Figure 3 is a schematic flow chart of a longitudinal control method in an embodiment of the present application;

[0026] Figure 4 is a schematic structural diagram of a longitudinal control device in an embodiment of the present application;

[0027] Figure 5 is a schematic flow chart of a longitudinal control method in a preferred embodiment of the present application;

[0028] Figure 6 is a schematic structural diagram of an electronic device in an embodiment of the present application. Detailed implementation manners

[0029] To make the objectives, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be clearly and completely described below in conjunction with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0030] Autopilot can generally be divided into upper-layer control and lower-layer control. For the upper-layer longitudinal control, each function obtains the tracking target speed or target position according to different function requirements, and calculates the target acceleration of the vehicle according to the control algorithm; then the lower-layer control module controls the torque or acceleration of the drive actuator and the deceleration of the brake actuator to track the target acceleration of the autopilot.

[0031] The following are two types of lower-layer control methods in the related art:

[0032] First, the lower-layer controller receives the target acceleration request a sent by the upper layer and determines the sign of the acceleration request a. When the acceleration a is positive, the acceleration a instruction is multiplied by a coefficient K to be converted into a torque instruction and sent to the drive actuator. When a is negative, a is directly sent to the brake actuator. Specifically, as shown in Figure 1 shown.

[0033] Second, collect the vehicle speed, acceleration, and engine torque values according to different working conditions in advance and calibrate them into a three-dimensional table. The lower-level controller receives the target acceleration request a sent by the upper layer and determines the sign of the acceleration request a. When the target acceleration request a is positive, the acceleration a and the current vehicle speed V are used to find the corresponding torque T through look-up table interpolation, and then the torque T command is sent to the actuator. When a is negative, a is directly sent to the brake actuator. Specifically, as shown in Figure 2 shown.

[0034] When the inventors were researching, they found that the above-mentioned lower-level control method generally does not consider the vehicle longitudinal dynamics model, and the conversion from acceleration to torque is only to multiply by a fixed coefficient. This method ignores the variability of the system state, such as the low speed and high speed of the vehicle, the slope of the road, etc., which does not conform to the actual physical object. Moreover, it is also very difficult to be close to the actual controlled vehicle by using the calibration method for the fixed coefficient. This method cannot achieve accurate control of the vehicle longitudinally.

[0035] In addition, although some methods take into account the deficiencies of the above practices, they use working condition calibration for the vehicle under different working conditions, collect the mapping relationship between the acceleration, speed and throttle pedal opening of the controlled object, and fit and generate a three-dimensional mapping table. When driving automatically, the throttle pedal opening command is queried and fitted according to the expected acceleration and the actual vehicle speed. The disadvantages of this method are:

[0036] a. It is very troublesome to calibrate and collect data, and its complexity is exponentially related to the number of parameters. Generally, passenger cars only consider the relationship between acceleration, speed and throttle pedal, which is already three-dimensional fitting. If it is for trucks, the change of vehicle mass also needs to be considered, and the complexity is even more huge.

[0037] b. The signal noise during the calibration process affects the accuracy of the data, and the repeatability of the same working condition is also not good.

[0038] The problems that still exist in the above methods are: the switching logic between braking and driving only depends on whether the acceleration given by the upper-level controller is positive or negative. If it is negative, it is braking, and vice versa for driving. But in fact, due to the damping existing in the vehicle itself, such as wind resistance and rolling resistance, so even if the upper-level gives a deceleration expectation (acceleration a is negative), it may not be necessary to brake with the brake, but only need to reduce the throttle opening.

[0039] Therefore, the above methods may cause frequent switching between braking and driving in some working conditions, making the passengers feel a sense of jerk. Since the reverse torque of the driver cannot be calculated, for electric vehicles, if there is no reverse torque, energy recovery cannot be achieved. Therefore, in some working conditions, other systems are needed to achieve the purpose of energy recovery.

[0040] In addition, the above methods cannot predict the problem of driving down long steep slopes in advance.

[0041] In view of the above deficiencies, the longitudinal control method in the embodiments of the present application solves the inaccuracy in longitudinal control due to the failure to consider vehicle longitudinal dynamics. At the same time, it can also reduce the calibration workload, optimize the switching logic of braking and driving, make the switching of longitudinal control between driving and braking smoother, and reduce the sense of jerk;

[0042] In addition, the method in the present application can take into account both energy recovery and engine braking, and at the same time take into account the problem of braking when going down long slopes.

[0043] The following will describe in detail the technical solutions provided by the embodiments of the present application with reference to the accompanying drawings.

[0044] The embodiments of the present application provide a longitudinal control method, as Figure 3 shown, a schematic flow diagram of the longitudinal control method in the embodiments of the present application is provided. The method at least includes the following steps S310 to step S350:

[0045] Step S310, receiving the acceleration value instruction required by the upper-layer controller.

[0046] For the upper-layer controller, when performing operations, it will issue instructions to the lower-layer control module. It should be noted that the above longitudinal control method is for the vehicle in the autonomous driving mode. That is to say, in the autonomous driving mode, at this time, the acceleration value instruction required by the upper-layer controller is received. At this time, the driver does not perform any takeover operations.

[0047] Specifically, autonomous driving can generally be divided into upper-layer control and lower-layer control. The upper-layer longitudinal control, according to different function requirements of each function, obtains the target speed or target position to be tracked, and calculates the target acceleration of the vehicle according to the control algorithm; then the lower-layer control module controls the torque or acceleration of the driving actuator and the deceleration of the braking actuator to track the target acceleration of autonomous driving.

[0048] In the lower-layer control module, the acceleration value instruction required by the upper-layer controller is received, that is, the acceleration value that the upper-layer controller expects to obtain.

[0049] It should be noted that the vehicle drive system can receive a driving instruction with positive torque and a braking instruction with a limited value of negative torque. At the same time, the braking controller in the vehicle braking system can only receive a negative acceleration (i.e., deceleration) instruction. The above receiving mode of the braking instruction is the main scenario targeted by the embodiments of the present application. That is to say, if it is negative acceleration, it can be responded to by the vehicle braking system. If it is positive acceleration or negative acceleration within a certain range, it can be responded to by the vehicle drive system.

[0050] In addition, usually only one of the vehicle drive system and the vehicle braking system can respond.

[0051] Step S320: Calculate the torque value corresponding to the acceleration value required by the upper-layer controller according to the vehicle longitudinal dynamics model.

[0052] For the vehicle longitudinal dynamics model, a well-known dynamics model in related technologies can be adopted, and no specific limitation is made in the embodiments of the present application.

[0053] By adding the vehicle longitudinal dynamics model, the torque value corresponding to the acceleration value required by the upper-layer controller can be calculated. For example, the required torque T is calculated through the vehicle longitudinal dynamics model.

[0054] Furthermore, it is also necessary to then determine whether the torque value is a positive torque value or a negative torque value. For example, determine whether torque T >= 0.

[0055] Preferably, after calculating the torque value corresponding to the acceleration value required by the upper-layer controller according to the vehicle longitudinal dynamics model, it further includes: in the case where the torque value is a positive torque, send the positive torque value to the electronic control unit of the drive actuator in the vehicle drive system.

[0056] Preferably, the vehicle longitudinal dynamics model includes:

[0057]

[0058] Where β is the conversion coefficient from driving force to torque, ρ is the air density, A is the frontal area, C d is the drag coefficient, V is the vehicle speed, m is the vehicle weight, θ is the slope, C R is the rolling resistance coefficient, and a is the acceleration.

[0059] Step S330: In the case where the torque value is a negative torque, determine whether the acceleration value is also negative.

[0060] Further determine whether the acceleration value required by the upper-layer controller is negative according to the judgment result of whether the torque value is a negative torque value or a positive torque value. When the torque value is a negative torque, determine whether the acceleration value is also negative. For example, determine whether the acceleration value is < 0.

[0061] It should be noted that here, whether the desired acceleration of the upper-layer controller is positive or negative is considered, and it is necessary to select whether to respond through the vehicle drive system or through the vehicle braking system according to whether it is positive or negative.

[0062] Different from the related technology, it is not considered that in actual situations, due to the damping existing in the vehicle itself, such as wind resistance and rolling resistance, so even if the upper-layer gives a desired deceleration (i.e., the acceleration a is negative), it may not be necessary to brake with the brake, but only need to reduce the throttle opening.

[0063] Therefore, through the above strategy, the frequent switching between braking and driving under certain working conditions is reduced, so as to eliminate the sense of jerk for the driver and passengers and achieve refined control.

[0064] Step S340: If it is a negative torque value and the acceleration value is negative, send the acceleration value command required by the upper controller to the vehicle braking system, and the vehicle braking system is configured to only receive negative acceleration commands.

[0065] If it is a negative torque value and the acceleration value is negative, it indicates that the vehicle braking system can respond to the acceleration value command required by the upper controller. Since the vehicle braking system is configured to only receive negative acceleration commands, it meets the requirements when it is a negative torque value and the acceleration value is negative.

[0066] Step S350: If it is a negative torque value, the acceleration value is non - negative, and the negative torque value is within the preset range, send the calculated torque value to the vehicle drive system, and the vehicle drive system is configured to receive positive torque and negative torque within the preset range.

[0067] If it is a negative torque value and the acceleration value is non - negative, it indicates that the vehicle drive system can respond to the acceleration value command required by the upper controller. Since the vehicle drive system is configured to receive positive torque and negative torque within the preset range, it meets the requirements when it is a negative torque value, the acceleration value is non - negative, and the negative torque value is within the preset range.

[0068] In some embodiments, the corresponding torque T is executed by a drive actuator in the vehicle drive system.

[0069] In an embodiment of the present application, when it is a negative torque value and the acceleration value is negative, and the negative acceleration command required by the upper controller is sent to the vehicle braking system, and the vehicle braking system is configured to only receive negative acceleration commands, it further includes: when the acceleration value is non - negative, determining whether the negative torque value is within the capability limit range of the vehicle drive system; if the negative torque value does not exceed the capability limit range, continue to send the negative torque value to the electronic control unit of the drive actuator in the vehicle drive system, and the capability limit range is used to represent the maximum negative torque value that can be received.

[0070] During specific implementation, when it is determined that the acceleration value is non - negative, it is also necessary to determine whether the negative torque value is within the capability limit range of the vehicle drive system (the capability limit range is used to represent the maximum negative torque value that can be received, such as - T max )). It can be understood that if the absolute value of the negative torque |T| is greater than T maxIt is considered that the capacity limit range is exceeded; otherwise, it is considered that the capacity limit range is not exceeded.

[0071] Further, if the negative torque value does not exceed the capacity limit range, the negative torque value is continuously sent to the electronic control unit of the drive actuator in the vehicle drive system. That is to say, since the brake controller of the vehicle's braking system cannot receive non-negative values and can only receive negative acceleration commands, the brake cannot directly respond to the upper-layer acceleration command at this time. Instead, it attempts to use the drive actuator in the vehicle drive system to respond to meet the acceleration requirements of the upper-layer controller.

[0072] In an embodiment of the present application, if the negative torque value exceeds the capacity limit range, the brake of the vehicle braking system is controlled to perform a spot brake, and the driver is reminded to take over. The exceeding of the capacity limit range is used to indicate that the drive actuator in the vehicle drive system currently does not have the ability to respond to the negative torque value through energy recovery.

[0073] During specific implementation, it is determined whether the negative torque value is within the capacity range of the drive actuator. If the limit range is not exceeded, for example, the absolute value of the torque |T|≥T max , the negative torque value is continuously sent to the electronic control unit of the drive actuator.

[0074] Further, if the limit is exceeded, it indicates that the current vehicle is going downhill with a relatively large slope. Neither the drive actuator of the vehicle drive system nor the brake actuator of the vehicle braking system can meet the acceleration requirements of the upper-layer controller. The vehicle can be spot-braked to remind the driver to take over and ensure safety.

[0075] In an embodiment of the present application, if the negative torque value exceeds the capacity limit range and this state continuously exists for a time exceeding the threshold time, the vehicle is gradually braked to a stop, and the driver is reminded to take over.

[0076] During specific implementation, if this state continuously exists for a time exceeding the threshold time (usually the threshold time can be calibrated), it indicates that the current vehicle is going down a long and steep slope. Since the brake of the vehicle braking system cannot brake for a long time to prevent the braking ability from seriously decreasing due to heat generation, the vehicle is gradually braked to a stop and the driver is reminded to take over to avoid accidents.

[0077] In an embodiment of the present application, if the acceleration value required by the upper-layer controller is non-negative and the torque is negative, it indicates that the vehicle is currently in a downhill state, and the vehicle drive system responds to the acceleration command of the upper-layer controller; if the negative torque value exceeds the capacity limit range, it indicates that the vehicle is currently going downhill and the slope value exceeds the threshold, and neither the vehicle braking system nor the vehicle drive system can respond to the acceleration command of the upper-layer controller.

[0078] In specific implementation, if the acceleration value required by the upper-layer controller is non-negative and the calculated torque is negative, it indicates that the vehicle is currently in a downhill state and deceleration is needed. The vehicle drive system responds to the acceleration instruction of the upper-layer controller.

[0079] If the negative torque value exceeds the range of the capability limit, it indicates that the vehicle is currently going downhill and the slope value exceeds the threshold. At this time, neither the vehicle braking system nor the vehicle drive system can respond to the acceleration instruction of the upper-layer controller. It is necessary to gradually stop the vehicle and remind the driver to take over to overcome the current risk.

[0080] The embodiment of the present application also provides a longitudinal control device 400, as Figure 4 shown, which provides a structural schematic diagram of the longitudinal control device in the embodiment of the present application. The longitudinal control device 400 at least includes: a receiving module 410, a calculating module 420, a judging module 430, a first execution module 440, and a second execution module 450, where:

[0081] In an embodiment of the present application, the receiving module 410 is specifically configured to: receive the acceleration value instruction required by the upper-layer controller.

[0082] For the upper-layer controller, when performing operations, it will issue instructions to the lower-layer control module. It should be noted that the above longitudinal control method is for the vehicle in the autonomous driving mode. That is to say, in the autonomous driving mode, at this time, the acceleration value instruction required by the upper-layer controller is received. At this time, the driver does not perform any takeover operations.

[0083] Specifically, autonomous driving can generally be divided into upper-layer control and lower-layer control. The longitudinal upper-layer control, according to different function requirements of each function, obtains the tracking target speed or target position, and calculates the target acceleration of the vehicle according to the control algorithm; then the lower-layer control module controls the torque or acceleration of the drive actuator and the deceleration of the brake actuator to track the target acceleration of autonomous driving.

[0084] The acceleration value instruction required by the upper-layer controller is received in the lower-layer control module, that is, the acceleration value that the upper-layer controller expects to obtain.

[0085] It should be noted that the vehicle drive system can receive the drive instruction of positive torque and the brake instruction of limited negative torque. At the same time, the brake controller in the vehicle braking system can only receive the instruction of negative acceleration (i.e., deceleration). The above receiving mode of the brake instruction is the main scenario targeted by the embodiment of the present application. That is to say, if it is negative acceleration, it can be responded to by the vehicle braking system. If it is positive acceleration or negative acceleration within a certain range, it can be responded to by the vehicle drive system.

[0086] In addition, usually only one of the vehicle drive system and the vehicle braking system can respond.

[0087] In an embodiment of the present application, the calculation module 420 is specifically configured to: calculate the torque value corresponding to the acceleration value required by the upper controller according to the vehicle longitudinal dynamics model.

[0088] For the vehicle longitudinal dynamics model, a well-known dynamics model in the related art can be adopted, and no specific limitation is made in the embodiments of the present application.

[0089] By adding the vehicle longitudinal dynamics model, the torque value corresponding to the acceleration value required by the upper controller can be calculated. For example, the required torque T is calculated through the vehicle longitudinal dynamics model.

[0090] Furthermore, it is also necessary to then determine whether the torque value is a positive torque value or a negative torque value. For example, determine whether torque T >= 0.

[0091] Preferably, after calculating the torque value corresponding to the acceleration value required by the upper controller according to the vehicle longitudinal dynamics model, it further includes: in the case where the torque value is a positive torque, sending the positive torque value to the electronic control unit of the drive actuator in the vehicle drive system.

[0092] Preferably, the vehicle longitudinal dynamics model includes:

[0093]

[0094] Wherein, β is the conversion coefficient from driving force to torque, ρ is the air density, A is the frontal area, C d is the wind resistance coefficient, V is the vehicle speed, m is the vehicle weight, θ is the slope, C R is the rolling resistance coefficient, and a is the acceleration.

[0095] In an embodiment of the present application, the judgment module 430 is specifically configured to: in the case where the torque value is a negative torque, judge whether the acceleration value is also negative.

[0096] Further judge whether the acceleration value required by the upper controller is negative according to the judgment result of whether the torque value is a negative torque value or a positive torque value. When the torque value is a negative torque, judge whether the acceleration value is also negative. For example, judge whether the acceleration value is < 0.

[0097] It should be noted that here, whether the desired acceleration of the upper controller is positive or negative is considered, and it is necessary to select whether to respond through the vehicle drive system or through the vehicle braking system according to whether it is positive or negative.

[0098] Different from the related art, it is not considered that in actual situations, due to the damping existing in the vehicle itself, such as wind resistance and rolling resistance, even if the upper layer gives an expectation of deceleration (i.e., the acceleration a is negative), it may not be necessary to brake with the brake, but only need to reduce the throttle opening.

[0099] Therefore, through the above strategy, the frequent switching between braking and driving in some working conditions that causes a sense of jerk to the passengers is reduced and refined control is achieved.

[0100] In an embodiment of the present application, the first execution module 440 is specifically configured to: if it is a negative torque value and the acceleration value is negative, send the acceleration value instruction required by the upper layer controller to the vehicle braking system, and the vehicle braking system is configured to only receive negative acceleration instructions.

[0101] If it is a negative torque value and the acceleration value is negative, it indicates that the vehicle braking system can respond to the acceleration value instruction required by the upper layer controller. Since the vehicle braking system is configured to only receive negative acceleration instructions, it meets the requirements when it is a negative torque value and the acceleration value is negative.

[0102] In an embodiment of the present application, the second execution module 450 is specifically configured to: if it is a negative torque value and the acceleration value is non - negative and the negative torque value is within a preset range value, send the calculated torque value to the vehicle drive system, and the vehicle drive system is configured to receive positive torque and negative torque within the preset range value.

[0103] If it is a negative torque value and the acceleration value is non - negative, it indicates that the vehicle drive system can respond to the acceleration value instruction required by the upper layer controller. Since the vehicle drive system is configured to receive positive torque and negative torque within the preset range value, it meets the requirements when it is a negative torque value, the acceleration value is non - negative, and the negative torque value is within the preset range value.

[0104] In some embodiments, the corresponding torque T is executed by the drive actuator in the vehicle drive system.

[0105] It can be understood that the above longitudinal control device can implement each step of the longitudinal control method provided in the foregoing embodiments. The relevant explanations about the longitudinal control method are all applicable to the longitudinal control device and will not be elaborated here.

[0106] To better illustrate the longitudinal control method in the embodiments of the present application, as Figure 5 shown, it specifically includes the following steps:

[0107] S1, the upper layer controller calculates the required acceleration a.

[0108] For the upper - layer controller, when performing operations, it will send instructions to the lower - layer control module. It should be noted that the above - mentioned longitudinal control method is for the vehicle in the autonomous driving mode. That is to say, in the autonomous driving mode, at this time, the acceleration value instruction required by the upper - layer controller is received. At this time, the driver does not perform any takeover operation.

[0109] Specifically, autonomous driving can generally be divided into upper - layer control and lower - layer control. The longitudinal upper - layer control, according to different function requirements of each function, obtains the target speed or target position of tracking, and calculates the target acceleration of the vehicle according to the control algorithm; then the lower - layer control module controls the torque or acceleration of the drive actuator and the deceleration of the brake actuator to track the target acceleration of autonomous driving.

[0110] In the lower - layer control module, the acceleration value instruction required by the upper - layer controller is received, that is, the acceleration value that the upper - layer controller expects to obtain.

[0111] S2, the lower - layer control module calculates the required torque T according to the torque dynamics model.

[0112] For the vehicle longitudinal dynamics model, a well - known dynamics model in the related art can be adopted, and it is not specifically limited in the embodiments of the present application.

[0113] By adding the vehicle longitudinal dynamics model, the torque value corresponding to the acceleration value required by the upper - layer controller can be calculated. For example, the required torque T is calculated through the vehicle longitudinal dynamics model.

[0114] Furthermore, it is also necessary to then determine whether the torque value is a positive torque value or a negative torque value. For example, it is determined whether torque T >= 0.

[0115] Preferably, after calculating the torque value corresponding to the acceleration value required by the upper - layer controller according to the vehicle longitudinal dynamics model, it further includes: in the case where the torque value is a positive torque, the positive torque value is sent to the electronic control unit of the drive actuator in the vehicle drive system.

[0116] S3, determine whether torque T is not less than 0.

[0117] S4, if so, the drive actuator executes torque T.

[0118] S5, if not, and the acceleration a is less than 0, then the brake executes acceleration a.

[0119] If it is a negative torque value and the acceleration value is negative, the acceleration value instruction required by the upper - layer controller is sent to the vehicle braking system, and the vehicle braking system is used to only receive negative acceleration instructions.

[0120] If it is a negative torque value and the acceleration value is negative, it indicates that the vehicle braking system can respond to the acceleration value command required by the upper controller. Since the vehicle braking system is used to receive only negative acceleration commands, it meets the requirements when it is a negative torque value and the acceleration value is negative.

[0121] S6, if not, and the acceleration a is greater than 0, then determine whether the torque T is not less than -T max , if so, drive the actuator to specify the torque T.

[0122] If it is a negative torque value, the acceleration value is non - negative, and the negative torque value is within the preset range value, then send the calculated torque value to the vehicle drive system, and the vehicle drive system is used to receive positive torque and negative torque within the preset range value.

[0123] In some embodiments, the automatic part in the vehicle automatic system executes the corresponding acceleration value (negative torque value and the acceleration value is non - negative).

[0124] If it is a negative torque value, the acceleration value is non - negative, and the negative torque value is within the preset range value, it indicates that the vehicle drive system can respond to the acceleration value command required by the upper controller. Since the vehicle drive system is used to receive positive torque and negative torque within the preset range value, it meets the requirements when it is a negative torque value, the acceleration value is non - negative, and the negative torque value is within the preset range value.

[0125] In some embodiments, the drive actuator in the vehicle drive system executes the corresponding torque T.

[0126] S7, if not, the brake executes a point - brake and reminds the driver to take over. If this state exceeds the set threshold time, it stops.

[0127] Figure 6 It is a schematic structural diagram of an electronic device according to an embodiment of the present application. Please refer to Figure 6 , at the hardware level, the electronic device includes a processor, and optionally also includes an internal bus, a network interface, and a memory. Among them, the memory may include a memory, such as a high - speed random - access memory (Random - Access Memory, RAM), and may also include a non - volatile memory, such as at least one disk memory, etc. Of course, the electronic device may also include other hardware required for other services.

[0128] The processor, network interface, and memory can be interconnected through an internal bus, which can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, an EISA (Extended Industry Standard Architecture) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 6 only a bidirectional arrow is used in

[0129] Memory, which is used to store programs. Specifically, the program can include program code, and the program code includes computer operation instructions. The memory can include a memory and a non-volatile memory, and provide instructions and data to the processor.

[0130] The processor reads the corresponding computer program from the non-volatile memory into the memory and then runs it, forming a longitudinal control device at the logical level. The processor executes the program stored in the memory and is specifically used to perform the following operations:

[0131] Receive the acceleration value instruction required by the upper controller;

[0132] Calculate the torque value corresponding to the acceleration value required by the upper controller according to the vehicle longitudinal dynamics model;

[0133] In the case where the torque value is a negative torque, determine whether the acceleration value is also negative;

[0134] If it is a negative torque value and the acceleration value is negative, send the acceleration value instruction required by the upper controller to the vehicle braking system, and the vehicle braking system is used to only receive negative acceleration instructions;

[0135] If it is a negative torque value, the acceleration value is non-negative, and the negative torque value is within the preset range value, send the calculated torque value to the vehicle drive system, and the vehicle drive system is used to receive positive torque and negative torque within the preset range value.

[0136] The above is as in this application Figure 3The method executed by the longitudinal control device disclosed in the illustrated embodiment can be applied to a processor or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. During implementation, the steps of the above method can be completed by the integrated logic circuit in the hardware of the processor or instructions in the form of software. The above processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in combination with the embodiments of the present application can be directly embodied as being executed and completed by the hardware decoding processor, or executed and completed by a combination of the hardware and software modules in the decoding processor. The software module may be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. This storage medium is located in the memory, and the processor reads the information in the memory and combines its hardware to complete the steps of the above method.

[0137] The electronic device can also execute Figure 3 the method executed by the longitudinal control device in Figure 3 the illustrated embodiment and implement the functions of the longitudinal control device in

[0138] The embodiments of the present application also propose a computer-readable storage medium that stores one or more programs. The one or more programs include instructions that, when executed by an electronic device including multiple application programs, can enable the electronic device to execute Figure 3 the method executed by the longitudinal control device in the illustrated embodiment and specifically used to execute:

[0139] Receive the acceleration value instruction required by the upper controller;

[0140] Calculate the torque value corresponding to the acceleration value required by the upper controller according to the vehicle longitudinal dynamics model;

[0141] In the case where the torque value is a negative torque, determine whether the acceleration value is also negative;

[0142] If the torque value is negative and the acceleration value is negative, the acceleration value command required by the upper controller is sent to the vehicle braking system, and the vehicle braking system is configured to receive only negative acceleration commands;

[0143] If the torque value is negative, the acceleration value is non-negative, and the negative torque value is within a preset range value, the calculated torque value is sent to the vehicle drive system, and the vehicle drive system is configured to receive positive torque and negative torque within the preset range value.

[0144] Those skilled in the art should understand that the embodiments of the present invention may be provided as a method, a system, or a computer program product. Therefore, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention may 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.

[0145] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (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, and the combination 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 processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices produce means for implementing the functions specified in one Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0146] 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 an instruction device that implements the functions specified in one Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0147] 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 generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide means for implementing the functions specified in one Figure 1 one process or multiple processes and / or blocks Figure 1Steps of the functions specified in one or more boxes.

[0148] In a typical configuration, a computing device includes one or more processors (CPUs), an input / output interface, a network interface, and memory.

[0149] The memory may include non-permanent memory in the form of computer-readable media, random access memory (RAM) and / or non-volatile memory such as read-only memory (ROM) or flash memory (flash RAM). Memory is an example of computer-readable media.

[0150] Computer-readable media includes permanent and non-permanent, removable and non-removable media and can store information by any method or technology. The information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette tapes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transitory media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media such as modulated data signals and carrier waves.

[0151] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but also other elements not expressly listed, or elements that are inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the statement "comprising a..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0152] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, system, or computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application 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.

[0153] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various modifications and variations can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A longitudinal control method, wherein, The method includes: Receiving an acceleration value instruction required by an upper-layer controller; Wherein, if the acceleration value required by the upper-layer controller is non-negative and the torque is negative, it indicates that the vehicle is currently in a downhill state, and the vehicle drive system responds to the acceleration instruction of the upper-layer controller; Calculating a torque value corresponding to the acceleration value required by the upper-layer controller according to the vehicle longitudinal dynamics model; When the torque value is a negative torque, determining whether the acceleration value is also negative to determine whether the desired acceleration of the upper-layer controller is positive or negative, and selecting whether to respond through the vehicle drive system or through the vehicle braking system according to whether it is positive or negative; If it is a negative torque value and the acceleration value is negative, sending the acceleration value instruction required by the upper-layer controller to the vehicle braking system, and the vehicle braking system is used to only receive negative acceleration instructions; If it is a negative torque value, the acceleration value is non-negative, and the negative torque value is within a preset range value, sending the calculated torque value to the vehicle drive system, and the vehicle drive system is used to receive positive torque and negative torque within the preset range value; Wherein, if the negative torque value exceeds the capability limit range, it indicates that the vehicle is currently going downhill and the slope value exceeds the threshold, and neither the vehicle braking system nor the vehicle drive system can respond to the acceleration instruction of the upper-layer controller.

2. The method according to claim 1, wherein If it is a negative torque value and the acceleration value is negative, then sending the acceleration value instruction required by the upper-layer controller to the vehicle braking system, and the vehicle braking system is used to only receive negative acceleration instructions, and further includes: When the acceleration value is non-negative, determining whether the negative torque value is within the capability limit range of the vehicle drive system; If the negative torque value does not exceed the capability limit range, continuing to send the negative torque value to the electronic control unit of the drive actuator in the vehicle drive system, and the capability limit range is used to represent the maximum negative torque value that can be received.

3. The method according to claim 2, wherein, If the negative torque value exceeds the capability limit range, controlling the brake of the vehicle braking system to perform a point brake and reminding the driver to take over, and the exceeding of the capability limit range is used to represent that the drive actuator in the vehicle drive system currently has no ability to respond to the negative torque value through energy recovery.

4. The method according to claim 2, wherein If the negative torque value exceeds the capability limit range and this state continuously exists for a time exceeding the threshold time, gradually braking the vehicle to a stop and reminding the driver to take over.

5. The method according to claim 1, wherein, After calculating the torque value corresponding to the acceleration value required by the upper-layer controller according to the vehicle longitudinal dynamics model, it further includes: When the torque value is a positive torque, sending the positive torque value to the electronic control unit of the drive actuator in the vehicle drive system.

6. The method according to claim 1, wherein, The vehicle longitudinal dynamics model includes: Among them, β is the conversion coefficient from driving force to torque, ρ is the air density, A is the frontal area, C d is the drag coefficient, V is the vehicle speed, m is the vehicle weight, θ is the slope, C R is the rolling resistance coefficient, and a is the acceleration.

7. A longitudinal control device, wherein, The device includes: A receiving module, configured to receive an acceleration value instruction required by an upper-layer controller; Wherein, if the acceleration value required by the upper-layer controller is non-negative and the torque is negative, it indicates that the vehicle is currently in a downhill state, and the vehicle drive system responds to the acceleration instruction of the upper-layer controller; A calculation module, configured to calculate a torque value corresponding to an acceleration value required by the upper-layer controller according to a vehicle longitudinal dynamics model; A judgment module, configured to, when the torque value is a negative torque, judge whether the acceleration value is also negative, so as to judge whether the desired acceleration of the upper-layer controller is positive or negative, and select whether to respond through a vehicle drive system or through a vehicle braking system according to whether it is positive or negative; A first execution module, configured to, if the torque value is negative and the acceleration value is negative, send an acceleration value instruction required by the upper-layer controller to a vehicle braking system, where the vehicle braking system is configured to only receive a negative acceleration instruction; A second execution module, configured to, if the torque value is negative and the acceleration value is non-negative and the negative torque value is within a preset range value, send the calculated torque value to a vehicle drive system, where the vehicle drive system is configured to receive a positive torque and a negative torque within the preset range value; Wherein, when the negative torque value exceeds the capability limit range, it indicates that the vehicle is currently going downhill and the slope value exceeds a threshold, and neither the vehicle braking system nor the vehicle drive system can respond to the acceleration instruction of the upper-layer controller.

8. An electronic device, comprising: A processor; And A memory arranged to store computer-executable instructions, which when executed cause the processor to execute the method according to any one of claims 1 to 6.

9. A computer-readable storage medium, the computer-readable storage medium storing one or more programs, which when executed by an electronic device including a plurality of application programs, cause the electronic device to execute the method according to any one of claims 1 to 6.

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