Transverse control method of mobile equipment and related equipment

Abstract

The invention relates to a transverse control method and device of mobile equipment, an electronic device and a storage medium. The method comprises the following steps: acquiring a planned driving path and real-time driving information of the mobile equipment; determining a target tracking point on the planned driving path according to the real-time driving information; determining each transverse deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculating a transverse feedback instruction acceleration of the mobile device according to each transverse deviation item; based on an Ackerman steering model formula, calculating a front wheel angle of the mobile equipment according to the transverse feedback instruction acceleration; and the front wheel angle is converted into an instruction EPS angle, and the instruction EPS angle is sent to the electric power steering system, so that the electric power steering system conducts transverse control according to the instruction EPS angle. According to the invention, the control precision is improved, and the riding safety and comfort of the automatic driving mobile equipment are improved.

Description

Technical Field

[0001] The present application relates to the field of autonomous driving technology, and in particular to a lateral control method for a mobile device and related equipment. Background Art

[0002] With the continuous development of automobile technology, autonomous vehicles are becoming more and more popular. Existing autonomous vehicle control technology divides control into lateral control and longitudinal control. As an important part of autonomous driving technology, researching and improving the accuracy of vehicle lateral control is of great help in improving the performance of autonomous vehicles.

[0003] In the related technologies, there are various lateral control algorithms, including lateral control methods based on model optimization, such as linear quadratic regulator (LQR) control, model predictive control (MPC) control, etc.; lateral control methods based on geometric methods, such as pure tracking control, Stanley algorithm, etc.; lateral control methods based on feedback, such as PID (proportional-integral-derivative control) control algorithm. Among them, LQR control and MPC control have higher accuracy, but the algorithms are more complex, with high requirements on computing power, and their applicable scenarios are relatively limited; the pure tracking control algorithm is simple, with low requirements on computing power, but the control accuracy is not high, and it is mainly used in medium and low speed scenarios. In high-speed scenarios, problems such as increased steady-state error and dragon drawing will occur, resulting in lower safety and comfort of riding in autonomous driving vehicles; the feedback-based lateral control method is mainly used in medium and low speed scenarios, mainly based on the lateral deviation and heading deviation between the vehicle and the tracking path, and controls the autonomous driving vehicle through the PID control algorithm output command EPS angle. However, since the heading deviation is coupled with the influence of vehicle speed, the PID heading deviation weight varies greatly at different vehicle speeds, the debugging difficulty increases accordingly, and the algorithm is also less robust to external interference. Summary of the invention

[0004] In order to overcome the problems existing in the related art, the present application provides a lateral control method of a mobile device and related equipment, which can improve the safety and comfort of riding in an autonomous driving vehicle.

[0005] A first aspect of the present application provides a method for horizontal control of a mobile device, comprising:

[0006] Obtain the planned driving path and real-time driving information of the mobile device;

[0007] Determine a target tracking point on the planned driving path according to the real-time driving information;

[0008] Determining each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculating the lateral feedback instruction acceleration of the mobile device according to each lateral deviation item;

[0009] Based on the Ackerman steering model formula, the front wheel angle of the mobile device is calculated according to the lateral feedback instruction acceleration;

[0010] The front wheel angle is converted into a command EPS angle, and the command EPS angle is sent to an electric power steering system, so that the electric power steering system performs lateral control according to the command EPS angle.

[0011] A second aspect of the present application provides a lateral control device for a mobile device, comprising:

[0012] A first processing unit, used to obtain a planned driving path and real-time driving information of a mobile device;

[0013] A second processing unit, configured to determine a target tracking point on the planned driving path according to the real-time driving information;

[0014] a third processing unit, configured to determine each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculate a lateral feedback instruction acceleration of the mobile device according to each lateral deviation item;

[0015] A fourth processing unit, configured to calculate a front wheel angle of the mobile device according to the lateral feedback instruction acceleration based on an Ackerman steering model formula;

[0016] The fifth processing unit is used to convert the front wheel angle into a command EPS angle, and send the command EPS angle to the electric power steering system, so that the electric power steering system performs lateral control according to the command EPS angle.

[0017] A third aspect of the present application provides an electronic device, including:

[0018] Processor; and

[0019] The memory stores executable codes thereon, and when the executable codes are executed by the processor, the processor is caused to execute the method as described above.

[0020] A fourth aspect of the present application provides a non-transitory machine-readable storage medium having executable code stored thereon. When the executable code is executed by a processor of an electronic device, the processor is caused to execute the method as described above.

[0021] A fifth aspect of the present application provides a mobile device, including the electronic device described above.

[0022] The technical solution provided by this application may have the following beneficial effects:

[0023] The technical solution of the present application provides a lateral control method, device, electronic device and storage medium for a mobile device, by obtaining the planned driving path and real-time driving information of the mobile device; determining the target tracking point on the planned driving path according to the real-time driving information; determining each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculating the lateral feedback command acceleration of the mobile device according to each lateral deviation item; calculating the front wheel angle of the mobile device according to the lateral feedback command acceleration based on the Ackerman steering model formula; converting the front wheel angle into a command EPS angle, and sending the command EPS angle to the electric power steering system, so that the electric power steering system performs lateral control according to the command EPS angle. The lateral control method provided in the embodiment of the present application has low algorithm complexity, good versatility, and a wide range of applicable scenarios, and can avoid the problem of low safety and comfort of riding in an autonomous driving mobile device caused by the lateral control algorithm determining the lateral control of the vehicle in the related art.

[0024] The technical solution provided in the embodiment of the present application calculates various lateral deviation items of the mobile device by determining the target tracking points, and converts the front wheel angles calculated using the lateral deviation items to obtain the final command EPS angle, thereby improving the control accuracy and enhancing the safety and comfort of riding in the autonomous driving mobile device.

[0025] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other objects, features and advantages of the present application will become more apparent through a more detailed description of exemplary embodiments of the present application in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the present application.

[0027] Figure 1 is a flow chart showing a method for horizontal control of a mobile device according to an embodiment of the present application;

[0028] Figure 2 is a schematic diagram showing target tracking points in an embodiment of the present application;

[0029] Figure 3 is a structural schematic diagram of a lateral control system of a mobile device according to an embodiment of the present application;

[0030] Figure 4 is a structural schematic diagram of a lateral control device of a mobile device according to an embodiment of the present application;

[0031] Figure 5 It is a schematic diagram of the structure of an electronic device shown in an embodiment of the present application. DETAILED DESCRIPTION

[0032] The preferred embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0033] The applicant found in the research that the lateral control solutions provided in the relevant technologies are relatively mature methods for solving lateral control problems, and they are good solutions in appropriate scenarios. For example, the existing geometry-based lateral control method is relatively simple to implement, and has low requirements for path smoothness. It is mainly used in medium and low speed scenarios. In high-speed scenarios, there will be problems such as increased steady-state error and dragon drawing; the existing model-optimization-based lateral control method can achieve good control effects in medium and high speed scenarios, but its calculation is time-consuming, and the debugging parameters are more complicated; the existing feedback-based lateral control method is mainly used in medium and low speed scenarios, mainly based on the lateral deviation and heading deviation of the vehicle and the tracking path through the PID control algorithm, and the output command EPS angle is used to control the autonomous driving vehicle. However, due to the coupling of the heading deviation with the influence of the vehicle speed, the PID heading deviation weight varies greatly at different vehicle speeds, the debugging difficulty increases accordingly, and the algorithm is also less robust to external interference.

[0034] In response to the above problems, an embodiment of the present application provides a lateral control method for a mobile device, which can improve the safety and comfort of riding in an autonomous driving vehicle.

[0035] It should be noted that the lateral control of a mobile device is part of trajectory control, and is often referred to as lateral planning. Common structured lateral control methods require the following input information: planned driving path (including the path to be tracked, the planned speed of each waypoint on the path to be tracked, the planned curvature, the planned heading, etc.) and real-time driving information (including the vehicle positioning information, such as the vehicle's position, orientation, speed, yaw rate, etc.).

[0036] The technical solution of the embodiments of the present application is described in detail below with reference to the accompanying drawings.

[0037] Figure 1: is a flow chart of a lateral control method of a mobile device shown in an embodiment of the present application. The present application embodiment can be applicable to scenarios such as vehicle automatic driving. The method can be executed by a lateral control device of a mobile device provided in an embodiment of the present application. The device can be integrated in an electronic device such as a computer, a mobile phone, an unmanned vehicle, etc. The device can be implemented in software and / or hardware. In a specific embodiment, the device can be integrated in a vehicle.

[0038] See also Figure 1 The present application provides a method for horizontal control of a mobile device, the method specifically comprising the following steps:

[0039] S10: Obtaining the planned driving path and real-time driving information of the mobile device.

[0040] In a specific embodiment, for step S10, when the lateral deviation of the vehicle can no longer meet the specific requirements, a lateral control instruction is generated. When the planning system receives the lateral control instruction, it obtains the real-time driving information of the mobile device (such as the position, orientation, speed, yaw angular velocity and other information of the vehicle) according to the on-board positioning device and obtains the planned current frame planned driving path (including the path to be tracked, the planned speed of each waypoint on the path to be tracked, the planned curvature, the planned heading and other information) from the path planning system.

[0041] It should be noted that the path to be tracked is the movement trajectory of the vehicle planned according to the initial position and destination of the mobile device, and the actual driving information of the mobile device includes the actual driving position, actual driving speed, actual driving direction and actual yaw rate of the current vehicle, etc., which is not limited in the embodiment of the present invention. Specifically, the planned driving path of the mobile device is completed by the trajectory planning system, and the actual driving information of the mobile device is detected and identified by the positioning system.

[0042] In a specific embodiment, if a mobile device needs to go from A to B, A and B are input into the trajectory planning system of the mobile device. The system will plan several suitable routes based on the distance between A and B, the construction of urban roads, the number of traffic lights and their duration, and then select a route that best meets the current driving needs of the mobile device as the planned driving route. Optionally, during the automatic driving of the mobile device, the positioning system will detect the actual driving position, actual driving speed, actual driving direction, and real-time yaw angular velocity and other actual driving information of the vehicle in real time.

[0043] S11: Determine a target tracking point on the planned driving path according to the real-time driving information.

[0044] In a specific embodiment, for step S11, the target tracking point can be used to measure the distance, heading angle and other information between the actual driving state of the mobile device and the planned driving path, and provide corresponding data for the lateral control of the autonomous driving mobile device.

[0045] Optionally, the actual driving information includes a current driving position, and determining a target tracking point on the planned driving path based on the actual driving information includes: finding a point on the planned driving path that is closest to the current driving position to obtain the target tracking point.

[0046] In a specific embodiment, Figure 2 It is a schematic diagram of a target tracking point provided by an embodiment of the present invention. A mobile device needs to travel from A to B. A path that meets the current vehicle driving requirements can be selected as the planned driving path of the mobile device. Assume that the mobile device travels to a position between A and B. At this time, the positioning system detects that the actual driving position of the vehicle is O. Point C closest to position O is selected from the planned driving path of the mobile device as the target tracking point.

[0047] S12: Determine each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculate the lateral feedback instruction acceleration of the mobile device according to the each lateral deviation item.

[0048] In a specific embodiment, for step S12, determining each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculating the lateral feedback instruction acceleration of the mobile device according to each lateral deviation item includes:

[0049] Determining a lateral position deviation item, a lateral velocity deviation item, and a lateral acceleration deviation item of the mobile device according to the target tracking point and the real-time driving information;

[0050] Calculating a lateral feedback instruction acceleration of the mobile device according to the lateral position deviation term, the lateral velocity deviation term and the lateral acceleration deviation term;

[0051] The real-time driving information further includes: a current position, a current driving speed, a current yaw angular velocity, and a current orientation. The determining of a lateral position deviation item, a lateral speed deviation item, and a lateral acceleration deviation item of the mobile device based on the target tracking point and the real-time driving information includes:

[0052] Projecting the current position of the mobile device to the heading direction of the target tracking point, and determining the length of the obtained vertical line segment as the lateral position deviation item;

[0053] The lateral velocity deviation term is determined according to the following formula:

[0054] dl=v·sinθ

[0055] Wherein, dl is the lateral velocity deviation, v is the current speed of the mobile device, and θ is the deviation angle between the heading of the mobile device and the heading of the target tracking point;

[0056] The lateral acceleration deviation term is determined according to the following formula:

[0057]

[0058] Where, dll is the lateral acceleration deviation, v p is the planning speed of the target tracking point, ρ p is the planning curvature of the target tracking point, and ω is the yaw angular velocity of the mobile device.

[0059] In a specific embodiment, Figure 2 As shown, first find the waypoint C closest to the vehicle position on the path to be tracked, then project the vehicle position to the heading direction of point C, and the length of the resulting vertical line segment L is the lateral deviation l. The vehicle position is positive when it is on the right side of the heading direction of point C, and negative when it is on the left side of the heading direction of point C.

[0060] In a specific embodiment, Figure 2 As shown, first calculate the heading deviation θ between the vehicle and the position matching point C, then the lateral velocity deviation dl is calculated by the following formula:

[0061] dl=v·sinθ

[0062] Among them, dl is the lateral velocity deviation, v is the current speed of the mobile device, and θ is the deviation angle between the heading of the mobile device and the heading of the target tracking point.

[0063] In a specific embodiment, the lateral acceleration deviation term is determined according to the following steps:

[0064] First, calculate the lateral acceleration a of the position matching point A on the tracking path p :

[0065]

[0066] Then calculate the actual lateral acceleration a of the vehicle:

[0067] a=v·ω

[0068] The lateral acceleration deviation term dll is determined according to the following formula:

[0069]

[0070] Where, dll is the lateral acceleration deviation, v p is the planning speed of the target tracking point, ρ p is the planning curvature of the target tracking point, and ω is the yaw angular velocity of the mobile device.

[0071] Preferably, calculating the lateral feedback instruction acceleration of the mobile device according to the lateral position deviation term, the lateral velocity deviation term and the lateral acceleration deviation term comprises:

[0072] The lateral feedback command acceleration of the mobile device is calculated according to the following formula:

[0073]

[0074] Among them, a fb is the lateral feedback command acceleration, k1 is the weight of the lateral position deviation integral term, l is the lateral position deviation, k2 is the weight of the lateral position deviation term, k3 is the weight of the lateral velocity deviation term, dl is the lateral velocity deviation, k4 is the weight of the lateral acceleration deviation term, and dll is the lateral acceleration deviation.

[0075] It should be noted that the lateral feedback command acceleration is mainly composed of the following four parts: a lateral position deviation integral part (historical position deviation integration), a lateral position deviation part, a lateral velocity deviation part and a lateral acceleration deviation part.

[0076] In a specific embodiment, while calculating the lateral feedback command acceleration, the lateral feedforward command acceleration is also calculated. It should be noted that the lateral feedforward acceleration should be calculated using the speed and curvature of the waypoint. However, since there may be a certain deviation when the longitudinal control tracks the speed of the planned path waypoint, in order to ensure the tracking accuracy of the lateral control, the lateral feedforward command acceleration is calculated using the vehicle speed and the waypoint curvature. The lateral feedforward command acceleration of the mobile device is determined according to the following formula:

[0077] a ff =v 2 ·ρ p

[0078] Among them, a ff is the lateral feedforward command acceleration, ρ p is the feedforward curvature, and v is the current speed of the mobile device. p The value of is the average curvature of a distance d before the position matching point, and d is calculated as: d = 2·v·τ, where τ is the pure lag time of EPS.

[0079] S13: Based on the Ackerman steering model formula, the front wheel angle of the mobile device is calculated according to the lateral feedback instruction acceleration.

[0080] In a specific embodiment, for step S13, the Ackerman steering model formula can be used to obtain:

[0081]

[0082] Among them, α is the front wheel angle in radians, L is the wheelbase of the mobile device, and R is the turning radius of the mobile device.

[0083] The front wheel angle of the mobile device is determined according to the following formula:

[0084]

[0085] It should be noted that in order to avoid incorrect solution of the above formula when the vehicle speed is 0, the vehicle speed v should be constrained to a minimum value greater than 0.

[0086] In a specific embodiment, if the lateral feedforward command acceleration is taken into account, then the front wheel angle of the mobile device is determined according to the following formula:

[0087]

[0088] Among them, α is the front wheel angle in radians, L is the wheelbase of the mobile device, and R is the turning radius of the mobile device.

[0089] S14: Convert the front wheel angle into a command EPS angle, and send the command EPS angle to the electric power steering system, so that the electric power steering system performs lateral control according to the command EPS angle.

[0090] In a specific embodiment, for step S14, the front wheel angle is converted into a command EPS angle:

[0091]

[0092] Where β is the command EPS angle in degrees, k e It is the EPS transmission ratio. The transmission ratio refers to the ratio of the angular velocities of the two rotating components. Different vehicles have different transmission ratios.

[0093] After the command EPS angle is determined according to the above method, the command EPS angle is sent to the electric power steering system so that the electric power steering system performs lateral control according to the command EPS angle.

[0094] Further, based on the safety and comfort indicators, the maximum lateral command acceleration and the maximum lateral jerk are constrained. After determining the lateral command acceleration, the method may further include:

[0095] The amplitude and the rate of change of the lateral command acceleration are constrained according to the first set constraint condition, and the first set constraint condition of the amplitude of the lateral command acceleration is: max ≤a≤a max , where a is the lateral command acceleration, a max is the maximum lateral acceleration; the first setting constraint condition of the rate of change of the lateral command acceleration is: a last -j max ·dt≤a≤a last +j max ·dt, where a last is the lateral command acceleration output in the previous frame, j max is the maximum lateral acceleration, and dt is the control period of lateral control.

[0096] In a specific embodiment, the lateral command acceleration is: a=a fb +a ff

[0097] Specifically, the change rate constraint that the lateral command acceleration should satisfy is:

[0098] a last -j max ·dt≤a≤a last +j max ·dt

[0099] Where a is the lateral command acceleration, a last is the output lateral command acceleration of the previous frame, j max is the maximum lateral acceleration, and dt is the control period of lateral control.

[0100] The amplitude constraint that the lateral command acceleration should satisfy is:

[0101] -a max ≤a≤a max

[0102] Among them, a max is the maximum lateral acceleration.

[0103] In a specific embodiment, by constraining the maximum lateral command acceleration and the maximum lateral jerk, the lateral control can be constrained with different amplitudes and change rates according to comfort requirements, making it easier to achieve a more comfortable control effect.

[0104] Furthermore, based on safety and comfort indicators, and because EPS has angle and angular velocity constraints, it is necessary to constrain it according to the maximum angular velocity and amplitude of EPS. Before the vehicle to be controlled is laterally controlled according to the command EPS angle, it also includes:

[0105] The amplitude and the rate of change of the command EPS angle are constrained according to the second set constraint condition, and the second set constraint condition of the amplitude of the command EPS angle is: -β max ≤β≤β max , where β is the lateral command acceleration, β max is the maximum turning angle of the EPS, in degrees; the second setting constraint condition for the change rate of the command EPS angle is: Among them, β last The EPS angle of the command output in the previous frame, in degrees. is the maximum angular velocity of EPS, in degrees per second.

[0106] In a specific embodiment, the change rate constraint that the command EPS angle should satisfy is:

[0107]

[0108] Among them, β last The EPS angle of the command output in the previous frame, in degrees. is the maximum angular velocity of EPS, in degrees per second.

[0109] The amplitude constraint that the command EPS angle should satisfy is:

[0110] -β max ≤β≤β max

[0111] Among them, β max It is the maximum rotation angle of EPS, in degrees.

[0112] In a specific embodiment, by constraining the maximum angular velocity and amplitude of the EPS, the lateral control can be constrained with different amplitudes and change rates according to comfort requirements, making it easier to achieve a more comfortable control effect.

[0113] The technical solution of the embodiment of the present application is to obtain the planned driving path and real-time driving information of the mobile device; determine the target tracking point on the planned driving path according to the real-time driving information; determine each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculate the lateral feedback command acceleration of the mobile device according to each lateral deviation item; calculate the front wheel angle of the mobile device according to the lateral feedback command acceleration based on the Ackerman steering model formula; convert the front wheel angle into a command EPS angle, and send the command EPS angle to the electric power steering system, so that the electric power steering system performs lateral control according to the command EPS angle. The lateral control method provided in the embodiment of the present application has low algorithm complexity, good versatility, and a wide range of applicable scenarios. It can avoid the problem of low safety and comfort of riding in an autonomous driving mobile device caused by the lateral control algorithm determining the lateral control of the vehicle in the related art.

[0114] The technical solution provided in the embodiment of the present application calculates various lateral deviation items of the mobile device by determining the target tracking points, and converts the front wheel angles calculated using the lateral deviation items to obtain the final command EPS angle, thereby improving the control accuracy and enhancing the safety and comfort of riding in the autonomous driving mobile device.

[0115] Corresponding to the aforementioned application function implementation method embodiment, the present application also provides a lateral control device for a mobile device, an electronic device and corresponding embodiments.

[0116] Figure 4 is a schematic diagram of the structure of a lateral control device for a mobile device shown in an embodiment of the present application. Figure 4 The embodiment of the present application provides a lateral control device for a mobile device, the device specifically comprising: a first processing unit 41, a second processing unit 42, a third processing unit 43, a fourth processing unit 44 and a fifth processing unit 45, wherein:

[0117] The first processing unit 41 is used to obtain the planned driving path and real-time driving information of the mobile device;

[0118] A second processing unit 42, configured to determine a target tracking point on the planned driving path according to the real-time driving information;

[0119] A third processing unit 43 is used to determine each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculate the lateral feedback instruction acceleration of the mobile device according to each lateral deviation item;

[0120] A fourth processing unit 44 is configured to calculate the front wheel angle of the mobile device according to the lateral feedback instruction acceleration based on an Ackerman steering model formula;

[0121] The fifth processing unit 45 is used to convert the front wheel angle into a command EPS angle, and send the command EPS angle to the electric power steering system, so that the electric power steering system performs lateral control according to the command EPS angle.

[0122] Furthermore, the actual driving information includes a current driving position, and the second processing unit 42 is specifically configured to:

[0123] Find the point closest to the current driving position on the planned driving path to obtain the target tracking point.

[0124] Furthermore, the third processing unit 43 is specifically configured to:

[0125] Determining a lateral position deviation item, a lateral velocity deviation item, and a lateral acceleration deviation item of the mobile device according to the target tracking point and the real-time driving information;

[0126] Calculating a lateral feedback instruction acceleration of the mobile device according to the lateral position deviation term, the lateral velocity deviation term and the lateral acceleration deviation term;

[0127] The real-time driving information further includes: a current position, a current driving speed, a current yaw angular velocity, and a current orientation. The determining of a lateral position deviation item, a lateral speed deviation item, and a lateral acceleration deviation item of the mobile device based on the target tracking point and the real-time driving information includes:

[0128] Projecting the current position of the mobile device to the heading direction of the target tracking point, and determining the length of the obtained vertical line segment as the lateral position deviation item;

[0129] The lateral velocity deviation term is determined according to the following formula:

[0130] dl=v·sinθ

[0131] Wherein, dl is the lateral velocity deviation, v is the current speed of the mobile device, and θ is the deviation angle between the heading of the mobile device and the heading of the target tracking point;

[0132] The lateral acceleration deviation term is determined according to the following formula:

[0133]

[0134] Where, dll is the lateral acceleration deviation, v p is the planning speed of the target tracking point, ρ pis the planning curvature of the target tracking point, and ω is the yaw angular velocity of the mobile device.

[0135] Furthermore, the third processing unit 43 is specifically configured to:

[0136] The lateral feedback command acceleration of the mobile device is calculated according to the following formula:

[0137]

[0138] Among them, a fb is the lateral feedback command acceleration, k1 is the weight of the lateral position deviation integral term, l is the lateral position deviation, k2 is the weight of the lateral position deviation term, k3 is the weight of the lateral velocity deviation term, dl is the lateral velocity deviation, k4 is the weight of the lateral acceleration deviation term, and dll is the lateral acceleration deviation.

[0139] Furthermore, the fourth processing unit 44 is specifically configured to:

[0140] The front wheel angle of the mobile device is determined according to the following formula:

[0141]

[0142] Wherein, α is the front wheel angle of the mobile device, in radians, L is the wheelbase of the mobile device, and R is the turning radius of the mobile device.

[0143] Furthermore, the fifth processing unit 45 is specifically configured to:

[0144] The front wheel angle is converted into the command EPS angle according to the following formula:

[0145]

[0146] Where β is the command EPS angle in degrees, k e is the EPS gear ratio.

[0147] Furthermore, the device further comprises: a first constraint unit, wherein the first constraint unit is specifically used to constrain the amplitude and change rate of the lateral command acceleration according to a first set constraint condition, wherein the first set constraint condition of the amplitude of the lateral command acceleration is: max ≤a≤a max , where a is the lateral command acceleration, a max is the maximum lateral acceleration; the first setting constraint condition of the rate of change of the lateral command acceleration is: a last -j max ·dt≤a≤a last +j max ·dt, where a lastis the lateral command acceleration output in the previous frame, j max is the maximum lateral acceleration, and dt is the control period of lateral control.

[0148] Furthermore, the device further comprises: a second constraint unit, wherein the second constraint unit is specifically used for:

[0149] The amplitude and the rate of change of the command EPS angle are constrained according to the second set constraint condition, and the second set constraint condition of the amplitude of the command EPS angle is: -β max ≤β≤β max , where β is the lateral command acceleration, β max is the maximum turning angle of the EPS, in degrees; the second setting constraint condition for the change rate of the command EPS angle is: Among them, β last The EPS angle of the command output in the previous frame, in degrees. is the maximum angular velocity of EPS, in degrees per second.

[0150] The embodiment of the present application provides a lateral control device for a mobile device, wherein a planned driving path and real-time driving information of the mobile device are obtained by a first processing unit; a second processing unit determines a target tracking point on the planned driving path according to the real-time driving information; a third processing unit determines each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculates the lateral feedback command acceleration of the mobile device according to each lateral deviation item; a fourth processing unit calculates the front wheel angle of the mobile device according to the lateral feedback command acceleration based on the Ackerman steering model formula; and finally a fifth processing unit converts the front wheel angle into a command EPS angle, and sends the command EPS angle to an electric power steering system, so that the electric power steering system performs lateral control according to the command EPS angle. The lateral control method provided by the embodiment of the present application has low algorithm complexity, good versatility, and a wide range of applicable scenarios, and can avoid the problem of low safety and comfort of riding in an autonomous driving mobile device caused by the lateral control algorithm determining the lateral control of the vehicle in the related art.

[0151] The technical solution provided in the embodiment of the present application calculates various lateral deviation items of the mobile device by determining the target tracking points, and converts the front wheel angles calculated using the lateral deviation items to obtain the final command EPS angle, thereby improving the control accuracy and enhancing the safety and comfort of riding in the autonomous driving mobile device.

[0152] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated again here.

[0153] Figure 5 It is a schematic diagram of the structure of an electronic device shown in an embodiment of the present application.

[0154] See also Figure 5 , the electronic device 500 includes a memory 510 and a processor 520 .

[0155] The processor 520 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0156] The memory 510 may include various types of storage units, such as system memory, read-only memory (ROM), and permanent storage devices. Among them, ROM can store static data or instructions required by the processor 520 or other modules of the computer. The permanent storage device may be a readable and writable storage device. The permanent storage device may be a non-volatile storage device that does not lose the stored instructions and data even after the computer is powered off. In some embodiments, the permanent storage device uses a large-capacity storage device (such as a magnetic or optical disk, flash memory) as a permanent storage device. In some other embodiments, the permanent storage device may be a removable storage device (such as a floppy disk, optical drive). The system memory may be a readable and writable storage device or a volatile readable and writable storage device, such as a dynamic random access memory. The system memory may store some or all instructions and data required by the processor at runtime. In addition, the memory 510 may include any combination of computer-readable storage media, including various types of semiconductor memory chips (DRAM, SRAM, SDRAM, flash memory, programmable read-only memory), and disks and / or optical disks may also be used. In some embodiments, the memory 510 may include a readable and / or writable removable storage device, such as a laser disc (CD), a read-only digital versatile disc (e.g., DVD-ROM, double-layer DVD-ROM), a read-only Blu-ray disc, an ultra-density optical disc, a flash memory card (e.g., SD card, mini SD card, Micro-SD card, etc.), a magnetic floppy disk, etc. The computer-readable storage medium does not include carrier waves and transient electronic signals transmitted wirelessly or wired.

[0157] The memory 510 stores executable codes, and when the executable codes are processed by the processor 520 , the processor 520 can execute part or all of the methods described above.

[0158] The devices in this article can be servers, PCs, PADs, mobile phones, etc.

[0159] The present application also provides a computer program product, which, when executed on a data processing device, is suitable for executing a program for initializing the following method steps:

[0160] Obtain the planned driving path and real-time driving information of the mobile device;

[0161] Determine a target tracking point on the planned driving path according to the real-time driving information;

[0162] Determining each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculating the lateral feedback instruction acceleration of the mobile device according to each lateral deviation item;

[0163] Based on the Ackerman steering model formula, the front wheel angle of the mobile device is calculated according to the lateral feedback instruction acceleration;

[0164] The front wheel angle is converted into a command EPS angle, and the command EPS angle is sent to an electric power steering system, so that the electric power steering system performs lateral control according to the command EPS angle.

[0165] Optionally, the actual driving information includes a current driving position, and determining a target tracking point on the planned driving path according to the actual driving information includes:

[0166] Find the point closest to the current driving position on the planned driving path to obtain the target tracking point.

[0167] Optionally, determining each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculating the lateral feedback instruction acceleration of the mobile device according to each lateral deviation item includes:

[0168] Determining a lateral position deviation item, a lateral velocity deviation item, and a lateral acceleration deviation item of the mobile device according to the target tracking point and the real-time driving information;

[0169] Calculating a lateral feedback instruction acceleration of the mobile device according to the lateral position deviation term, the lateral velocity deviation term and the lateral acceleration deviation term;

[0170] The real-time driving information further includes: a current position, a current driving speed, a current yaw angular velocity, and a current orientation. The determining of a lateral position deviation item, a lateral speed deviation item, and a lateral acceleration deviation item of the mobile device based on the target tracking point and the real-time driving information includes:

[0171] Projecting the current position of the mobile device to the heading direction of the target tracking point, and determining the length of the obtained vertical line segment as the lateral position deviation item;

[0172] The lateral velocity deviation term is determined according to the following formula:

[0173] dl=v·sinθ

[0174] Wherein, dl is the lateral velocity deviation, v is the current speed of the mobile device, and θ is the deviation angle between the heading of the mobile device and the heading of the target tracking point;

[0175] The lateral acceleration deviation term is determined according to the following formula:

[0176]

[0177] Where, dll is the lateral acceleration deviation, v p is the planning speed of the target tracking point, ρ p is the planned curvature of the target tracking point, and ω is the yaw angular velocity of the mobile device. The lateral velocity deviation term is determined according to the following formula:

[0178] dl=v·sinθ

[0179] Wherein, dl is the lateral velocity deviation, v is the current speed of the mobile device, and θ is the deviation angle between the heading of the mobile device and the heading of the target tracking point;

[0180] The lateral acceleration deviation term is determined according to the following formula:

[0181]

[0182] Where, dll is the lateral acceleration deviation, v p is the planning speed of the target tracking point, ρ p is the planning curvature of the target tracking point, and ω is the yaw angular velocity of the mobile device.

[0183] Optionally, the calculating the lateral feedback instruction acceleration of the mobile device according to the lateral position deviation term, the lateral velocity deviation term and the lateral acceleration deviation term includes:

[0184] The lateral feedback command acceleration of the mobile device is calculated according to the following formula:

[0185]

[0186] Among them, a fb is the lateral feedback command acceleration, k1 is the weight of the lateral position deviation integral term, l is the lateral position deviation, k2 is the weight of the lateral position deviation term, k3 is the weight of the lateral velocity deviation term, dl is the lateral velocity deviation, k4 is the weight of the lateral acceleration deviation term, and dll is the lateral acceleration deviation.

[0187] Optionally, the calculating the front wheel angle of the mobile device based on the Ackerman steering model formula according to the lateral feedback instruction acceleration includes:

[0188] The front wheel angle of the mobile device is determined according to the following formula:

[0189]

[0190] Wherein, α is the front wheel angle of the mobile device, in radians, L is the wheelbase of the mobile device, and R is the turning radius of the mobile device.

[0191] Optionally, converting the front wheel angle into a command EPS angle includes:

[0192] The front wheel angle is converted into the command EPS angle according to the following formula:

[0193]

[0194] Where β is the command EPS angle in degrees, k e is the EPS gear ratio.

[0195] Optionally, after determining the lateral command acceleration, the method further includes:

[0196] The amplitude and the rate of change of the lateral command acceleration are constrained according to the first set constraint condition, and the first set constraint condition of the amplitude of the lateral command acceleration is: max ≤a≤a max , where a is the lateral command acceleration, a max is the maximum lateral acceleration; the first setting constraint condition of the rate of change of the lateral command acceleration is: a last -j max ·dt≤a≤a last +j max ·dt, where a last is the lateral command acceleration output in the previous frame, j max is the maximum lateral acceleration, and dt is the control period of lateral control.

[0197] Optionally, before performing lateral control on the vehicle to be controlled according to the command EPS angle, the method further includes:

[0198] The amplitude and the rate of change of the command EPS angle are constrained according to the second set constraint condition, and the second set constraint condition of the amplitude of the command EPS angle is: -β max ≤β≤β max , where β is the lateral command acceleration, β max is the maximum turning angle of the EPS, in degrees; the second setting constraint condition for the change rate of the command EPS angle is: Among them, β last The EPS angle of the command output in the previous frame, in degrees. is the maximum angular velocity of EPS, in degrees per second.

[0199] The present application also discloses a mobile device, which includes but is not limited to a vehicle with six autonomous driving technology levels, L0-L5, as defined by the Society of Automotive Engineers International (SAE International) or the Chinese national standard "Automotive Driving Automation Classification", for example, a vehicle device or a robot device having the following functions:

[0200] (1) Passenger-carrying function, such as family cars and buses;

[0201] (2) Cargo-carrying functions, such as ordinary trucks, van trucks, trailer trucks, closed trucks, tank trucks, flatbed trucks, container trucks, dump trucks, trucks with special structures, etc.;

[0202] (3) Tool functions, such as logistics delivery vehicles, automated guided vehicles (AGVs), patrol cars, cranes, hoists, excavators, bulldozers, forklifts, road rollers, loaders, off-road engineering vehicles, armored engineering vehicles, sewage treatment vehicles, sanitation vehicles, vacuum trucks, floor scrubbers, water sprinklers, sweeping robots, food delivery robots, shopping guide robots, lawn mowers, golf carts, etc.;

[0203] (4) Entertainment functions, such as entertainment vehicles, amusement park self-driving devices, balance vehicles, etc.;

[0204] (5) Special rescue functions, such as fire trucks, ambulances, power repair vehicles, engineering rescue vehicles, etc.

[0205] This application does not strictly limit the types of mobile devices, and will not be exhaustively listed here.

[0206] The scheme of the present application has been described in detail above with reference to the accompanying drawings. In the above embodiments, the description of each embodiment has its own emphasis. For the part that is not described in detail in a certain embodiment, refer to the relevant description of other embodiments. Those skilled in the art should also know that the actions and modules involved in the description are not necessarily required for the present application. In addition, it can be understood that the steps in the method of the embodiment of the present application can be adjusted in order, merged and deleted according to actual needs, and the modules in the device of the embodiment of the present application can be merged, divided and deleted according to actual needs.

[0207] In addition, the method according to the present application may also be implemented as a computer program or a computer program product, which includes computer program code instructions for executing some or all of the steps in the above method of the present application.

[0208] Alternatively, the present application can also be implemented as a non-temporary machine-readable storage medium (or computer-readable storage medium, or machine-readable storage medium) on which executable code (or computer program, or computer instruction code) is stored. When the executable code (or computer program, or computer instruction code) is executed by a processor of an electronic device (or electronic device, server, etc.), the processor executes part or all of the steps of the above-mentioned method according to the present application.

[0209] Those skilled in the art will further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the application herein may be implemented as electronic hardware, computer software, or combinations of both.

[0210] The flow chart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system and method according to multiple embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a part of a module, a program segment or a code, and the part of the module, the program segment or the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two continuous square boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or the flow chart, and the combination of the square boxes in the block diagram and / or the flow chart can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0211] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0212] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0213] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A method for horizontal control of a mobile device, characterized in that: include: Obtain the planned driving path and real-time driving information of the mobile device; Determine a target tracking point on the planned driving path according to the real-time driving information; Determining each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculating the lateral feedback instruction acceleration of the mobile device according to each lateral deviation item; Based on the Ackerman steering model formula, the front wheel angle of the mobile device is calculated according to the lateral feedback instruction acceleration; The front wheel angle is converted into a command EPS angle, and the command EPS angle is sent to an electric power steering system, so that the electric power steering system performs lateral control according to the command EPS angle.

2. The method according to claim 1, characterized in that The actual driving information includes a current driving position, and determining a target tracking point on the planned driving path according to the actual driving information includes: Find the point closest to the current driving position on the planned driving path to obtain the target tracking point.

3. The method according to claim 2, characterized in that The determining of each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculating the lateral feedback instruction acceleration of the mobile device according to each lateral deviation item, includes: Determining a lateral position deviation item, a lateral velocity deviation item, and a lateral acceleration deviation item of the mobile device according to the target tracking point and the real-time driving information; Calculating a lateral feedback instruction acceleration of the mobile device according to the lateral position deviation term, the lateral velocity deviation term and the lateral acceleration deviation term; The real-time driving information further includes: a current position, a current driving speed, a current yaw angular velocity, and a current orientation. The determining of a lateral position deviation item, a lateral speed deviation item, and a lateral acceleration deviation item of the mobile device based on the target tracking point and the real-time driving information includes: Projecting the current position of the mobile device to the heading direction of the target tracking point, and determining the length of the obtained vertical line segment as the lateral position deviation item; The lateral velocity deviation term is determined according to the following formula: dl=v·sinθ Wherein, dl is the lateral velocity deviation, v is the current speed of the mobile device, and θ is the deviation angle between the heading of the mobile device and the heading of the target tracking point; The lateral acceleration deviation term is determined according to the following formula: Where, dll is the lateral acceleration deviation, v p is the planning speed of the target tracking point, ρ p is the planning curvature of the target tracking point, and ω is the yaw angular velocity of the mobile device.

4. The method according to claim 3, characterized in that The calculating the lateral feedback instruction acceleration of the mobile device according to the lateral position deviation term, the lateral velocity deviation term and the lateral acceleration deviation term comprises: The lateral feedback command acceleration of the mobile device is calculated according to the following formula: Among them, a fb is the lateral feedback command acceleration, k1 is the weight of the lateral position deviation integral term, l is the lateral position deviation, k2 is the weight of the lateral position deviation term, k3 is the weight of the lateral velocity deviation term, dl is the lateral velocity deviation, k4 is the weight of the lateral acceleration deviation term, and dll is the lateral acceleration deviation.

5. The method according to claim 4, characterized in that The method of calculating the front wheel angle of the mobile device based on the Ackerman steering model formula and according to the lateral feedback instruction acceleration includes: The front wheel angle of the mobile device is determined according to the following formula: Wherein, α is the front wheel angle of the mobile device, in radians, L is the wheelbase of the mobile device, and R is the turning radius of the mobile device.

6. The method according to claim 5, characterized in that The converting the front wheel angle into a command EPS angle comprises: The front wheel angle is converted into the command EPS angle according to the following formula: Where β is the command EPS angle in degrees, k e is the EPS gear ratio.

7. The method according to any one of claims 1 to 6, characterized in that: After determining the lateral command acceleration, it also includes: The amplitude and the rate of change of the lateral command acceleration are constrained according to the first set constraint condition, and the first set constraint condition of the amplitude of the lateral command acceleration is: max ≤a≤a max , where a is the lateral command acceleration, a max is the maximum lateral acceleration; the first setting constraint condition of the rate of change of the lateral command acceleration is: a last -j max ·dt≤a≤a last +j max ·dt, where a last is the lateral command acceleration output in the previous frame, j max is the maximum lateral acceleration, d t is the control period of lateral control.

8. The method according to any one of claims 1 to 6, characterized in that: Before performing lateral control on the vehicle to be controlled according to the command EPS angle, the method further includes: The amplitude and the rate of change of the command EPS angle are constrained according to the second set constraint condition, and the second set constraint condition of the amplitude of the command EPS angle is: -β max ≤β≤β max , where β is the lateral command acceleration, β max is the maximum turning angle of the EPS, in degrees; the second setting constraint condition for the change rate of the command EPS angle is: Among them, β last The EPS angle of the command output in the previous frame, in degrees. is the maximum angular velocity of EPS, in degrees per second.

9. A lateral control device for a mobile device, characterized in that: include: A first processing unit, used to obtain a planned driving path and real-time driving information of a mobile device; A second processing unit, configured to determine a target tracking point on the planned driving path according to the real-time driving information; a third processing unit, configured to determine each lateral deviation item of the mobile device according to the target tracking point and the real-time driving information, and calculate a lateral feedback instruction acceleration of the mobile device according to each lateral deviation item; A fourth processing unit, configured to calculate a front wheel angle of the mobile device according to the lateral feedback instruction acceleration based on an Ackerman steering model formula; The fifth processing unit is used to convert the front wheel angle into a command EPS angle, and send the command EPS angle to the electric power steering system, so that the electric power steering system performs lateral control according to the command EPS angle.

10. An electronic device, characterized in that: include: processor; and a memory having executable codes stored thereon, which, when executed by the processor, causes the processor to execute the method according to any one of claims 1 to 8.

11. A non-transitory machine-readable storage medium, characterized in that: An executable code is stored thereon, and when the executable code is executed by a processor of an electronic device, the processor is caused to execute the method as claimed in any one of claims 1 to 8.

12. A mobile device, characterized in that: The electronic device comprising claim 10.

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