Vehicle positioning method and device, vehicle and storage medium

Abstract

The invention discloses a vehicle positioning method and device, a vehicle and a storage medium, and the method comprises the steps: determining a yaw velocity null drift value of a rear axis at a target time point according to the yaw velocity of the rear axis of the vehicle and the motion state information of the vehicle at the target time point; and according to the yaw velocity null drift value of the rear axle center at the target time point, determining a target positioning parameter of the rear axle center at the target time point. According to the method, the yaw velocity null-drift value of the rear axle center is matched with the motion state of the vehicle, and is not a pre-calibrated fixed yaw velocity null-drift value any more, so that the yaw velocity null-drift value determined according to the method is accurate, and the accuracy of the yaw velocity null-drift value is improved. Therefore, the zero drift value of the yaw velocity at the target time point according to the rear axis is more accurate, and the accuracy of vehicle positioning is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and more specifically, to a vehicle positioning method, device, vehicle and storage medium. Background Art

[0002] At present, the vehicle's autonomous driving function can use the data collected by various sensors in the vehicle to perform dead reckoning, for example, based on data collected by the global positioning system, gyroscope, accelerometer, steering wheel angle sensor, etc. However, due to the structural factors of the gyroscope itself, the gyroscope has a zero drift value. Therefore, it is necessary to calibrate the zero drift value of the gyroscope first, and then determine the vehicle's yaw rate based on the calibrated zero drift value and the real-time yaw rate of the gyroscope.

[0003] However, in the existing solution, the zero drift value calibrated for the gyroscope is inaccurate, resulting in inaccurate yaw rate of the vehicle determined according to the calibrated zero drift value, causing low positioning accuracy of the vehicle according to the yaw rate of the vehicle. Summary of the invention

[0004] The present application proposes a vehicle positioning method, device, vehicle and storage medium to provide a vehicle positioning means with high accuracy.

[0005] In a first aspect, an embodiment of the present application provides a vehicle positioning method, the method comprising:

[0006] Determine the yaw angular velocity zero drift value of the rear axle at the target time point according to the yaw angular velocity of the rear axle of the vehicle and the motion state information of the vehicle at the target time point;

[0007] According to the yaw angular velocity zero drift value of the rear axle at the target time point, the target positioning parameters of the rear axle at the target time point are determined.

[0008] In a second aspect, an embodiment of the present application further provides a vehicle positioning device, the device comprising:

[0009] A zero drift value determination module is used to determine the yaw angular velocity zero drift value of the rear axle at a target time point according to the yaw angular velocity of the rear axle of the ego vehicle and the motion state information of the ego vehicle at the target time point;

[0010] The positioning module is used to determine the target positioning parameters of the rear axle at the target time point according to the yaw angular velocity zero drift value of the rear axle at the target time point.

[0011] In a third aspect, an embodiment of the present application further provides a vehicle, comprising: one or more processors; a memory; one or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the one or more processors, and the one or more programs are configured to execute the method of the first aspect above.

[0012] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, which stores a program code executable by a processor, and when the program code is executed by the processor, the processor executes the above method.

[0013] The present application provides a vehicle positioning method, device, vehicle and storage medium. In the present application, the yaw velocity zero drift value of the rear axle of the vehicle at the target time point is determined according to the yaw velocity of the rear axle of the vehicle and the motion state information of the vehicle at the target time point. The yaw velocity zero drift value of the rear axle is consistent with the motion state of the vehicle and is no longer a pre-calibrated fixed yaw velocity zero drift value, so that the yaw velocity zero drift value determined in the manner of the present application is more accurate, so that the target positioning parameters of the rear axle at the target time point are determined more accurately according to the yaw velocity zero drift value of the rear axle at the target time point, thereby improving the accuracy of vehicle positioning.

[0014] Other features and advantages of the embodiments of the present application will be described in the subsequent description, and partly become apparent from the description, or can be understood by practicing the embodiments of the present application. The purposes and other advantages of the embodiments of the present application can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 A schematic diagram of a vehicle hardware environment suitable for an embodiment of the present application is shown.

[0017] Figure 2 A flow chart of a vehicle positioning method proposed according to an embodiment of the present application is shown.

[0018] Figure 3 Shows Figure 2 The corresponding embodiment is a flowchart of step S120 in an embodiment.

[0019] Figure 4A schematic diagram showing the relative position of a particle before and after rotation in an embodiment of the present application.

[0020] Figure 5 A schematic diagram showing a vehicle positioning process in an embodiment of the present application.

[0021] Figure 6 A structural block diagram of a vehicle positioning device proposed in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0022] In order to make those skilled in the art better understand the present application scheme, the technical scheme in the present application embodiment will be clearly and completely described below in conjunction with the drawings in the present application embodiment. Obviously, the described embodiment is only a part of the present application embodiment, rather than all the embodiments. The components of the present application embodiment usually described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the present application for protection, but merely represents the selected embodiment of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0023] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0024] Reference Figure 1 , Figure 1 A schematic diagram of a vehicle hardware environment suitable for an embodiment of the present application is shown, wherein the vehicle 100 includes a driving system 110, which may have multiple built-in autonomous driving functions. The driving system 110 may store an electronic map, and the driving system 110 may plan a driving route based on the electronic map stored in the driving system, and may also control the vehicle's autonomous driving based on the planned driving route.

[0025] The driving system 110 may include a data acquisition device 111 , one or more (only one is shown in the figure) processors 112 , and a memory 113 .

[0026] The data acquisition device 111 is used to detect various signals or data of the vehicle. For example, the data acquisition device 111 can be used to collect the yaw rate and motion state information of the vehicle. For example, the data acquisition device 111 can include various gyroscopes for yaw rate.

[0027] The processor 112 may be a microcontroller unit (MCU) having a built-in memory 113 . The memory 113 stores a program that can execute the contents of the following embodiments, and the processor 112 may execute the program stored in the memory 113 .

[0028] The processor 112 may include one or more processors. The processor 112 uses various interfaces and lines to connect various parts of the entire vehicle 100, and executes various functions of the vehicle 100 and processes data by running or executing instructions, programs, code sets or instruction sets stored in the memory 113, and calling data stored in the memory 113.

[0029] The memory 113 may include a random access memory (RAM) or a read-only memory (ROM). The memory 15 may be used to store instructions, programs, codes, code sets or instruction sets. The memory 15 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for implementing at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the following various method embodiments, etc.

[0030] See also Figure 1 , Figure 1 A flow chart of a vehicle positioning method proposed according to an embodiment of the present application is shown, which is used for a vehicle, and the method includes:

[0031] S110 , determining a yaw angular velocity zero drift value of the rear axle at the target time point according to the yaw angular velocity of the rear axle of the vehicle and the motion state information of the vehicle at the target time point.

[0032] The vehicle in this embodiment may be an electric vehicle or a fuel vehicle, or may be a sedan, an SUV, a bus, a truck, etc., and the self-vehicle may refer to the vehicle itself.

[0033] The target time point may refer to any time point, for example, each current time point during the driving process of the ego vehicle can be taken as a target time point, so as to determine the yaw angular velocity zero drift value of the rear axle of the ego vehicle at the target time point according to the yaw angular velocity collected by the ego vehicle and the motion state information of the ego vehicle at the target time point.

[0034] The yaw angular velocity of the rear axle of the vehicle may refer to the yaw angular velocity collected by the gyroscope of the vehicle. The yaw angular velocity of the rear axle may include the yaw angular velocity of the rear axle at a target time point, and the yaw angular velocity of the rear axle may also include the yaw angular velocity of the rear axle before the target time point.

[0035] The motion state information of the vehicle refers to information used to indicate the motion state of the vehicle. The motion state may include a stationary state and a moving state. Accordingly, the motion state information may indicate that the vehicle is in a stationary state at a target time point, and the motion state information may also indicate that the vehicle is in a moving state at a target time point.

[0036] The yaw rate zero drift value refers to the small-angle random offset or drift of the measurement axis of the gyroscope relative to the true north direction or a specific reference base direction when the gyroscope is in a stationary state. The yaw rate zero drift value is difficult to avoid and exists when the vehicle is in a stationary state or in a moving state. The difference is that the yaw rate zero drift value may be different depending on the vehicle's moving state.

[0037] As mentioned above, the yaw angular velocity zero drift value of the rear axle of the vehicle will be different depending on the motion state of the vehicle. Therefore, in the present application, it is necessary to determine the yaw angular velocity zero drift value of the rear axle of the vehicle at the target time point based on the motion state information of the vehicle at the target time point.

[0038] In some embodiments, S110 may include: if the motion state information indicates that the vehicle is in a stationary state at the target time point, and the duration between the target time point and the first time point exceeds the first duration, according to the yaw angular velocity of the rear axle between the second time point and the target time point, determine the yaw angular velocity zero drift value of the rear axle at the target time point; the first time point is the time point when the vehicle enters the stationary state; the second time point is the time point delayed by the first duration from the first time point. The first duration may be determined according to the requirements and the specific structure of the gyroscope, for example, the first duration is 1.5s.

[0039] In the present application, it is detected that the vehicle enters a power-on state from a power-off state, and it is determined that the vehicle enters a stationary state, or it is detected that the speed of the vehicle becomes 0, and it is determined that the vehicle enters a stationary state.

[0040] When the vehicle enters a stationary state, the yaw angular velocity zero drift value is in a fluctuating state for a period of time after the vehicle enters the stationary state (that is, it is in a fluctuating state within the first time period after the vehicle enters the prohibited state). The yaw angular velocity zero drift value is unstable, and it is necessary to discard the yaw angular velocity within the first time period after the vehicle enters the stationary state. Therefore, in the present application, if the motion state information indicates that the vehicle is in a stationary state at a target time point, and the time period between the target time point and the first time point exceeds the first time period, it is necessary to postpone the time point when the vehicle enters the stationary state (that is, the first time) by the first time period to obtain a second time point, and determine the yaw angular velocity zero drift value of the rear axle at the target time point based on the yaw angular velocity collected between the second time point and the target time point.

[0041] That is, taking the time point when the vehicle enters a stationary state as the starting point, delaying for a first period of time, and determining the yaw angular velocity zero drift value of the rear axle at the target time point according to the yaw angular velocity zero drift value collected after the first period of delay, thereby discarding the yaw angular velocity during the period when the yaw angular velocity zero drift value is unstable, effectively improving the accuracy of the yaw angular velocity zero drift value determined for the stationary state.

[0042] If the motion state information indicates that the ego vehicle is in a stationary state at the target time point, and the duration between the target time point and the first time point does not exceed the first duration, this means that the yaw velocity zero drift value is unstable, and the yaw velocity zero drift value determined based on the yaw velocity between the target time point and the first time point is accurate. At this time, the yaw velocity zero drift value may not be calculated, and the yaw velocity zero drift value of the rear axle of the ego vehicle when the ego vehicle was in a stationary state the last time is obtained as the yaw velocity zero drift value of the rear axle of the ego vehicle at the target time point.

[0043] Optionally, the above-mentioned determination of the yaw velocity zero drift value of the rear axle at the target time point based on the yaw velocity of the rear axle between the second time point and the target time point includes: calculating the average value of the yaw velocity of the rear axle in the target time period as the yaw velocity zero drift value of the rear axle at the target time point; wherein, when the duration between the target time point and the second time point is not greater than the second duration, the target time period is the period between the target time point and the second time point; when the duration between the target time point and the second time point is greater than the second duration, the target time period is the period with the target time point as the end time point and a duration of a third duration, the third duration being the duration obtained by taking the remainder of the second duration based on the duration between the target time point and the second time point; the second duration is greater than the first duration. wherein the second duration can be a value set based on demand, such as 10s.

[0044] That is to say, after reaching the second time point, the collected yaw angular velocity starts to accumulate, and when the accumulated time does not exceed the second time point, the target time point is reached, the accumulated result of the yaw angular velocity is divided by the accumulated number of yaw angular velocity (the number of yaw angular velocity collected between the target time point and the second time point) to obtain the average value, which is used as the yaw angular velocity zero drift value of the rear axle of the vehicle at the target time point; when the accumulated time exceeds the second time point, re-accumulation is performed, and each time the accumulated time reaches the second time point, re-accumulation is performed until the target time point is reached, and the last accumulated yaw angular velocity is divided by the last accumulated number of yaw angular velocity to obtain the average value, which is used as the yaw angular velocity zero drift value of the rear axle of the vehicle at the target time point.

[0045] In this way, accumulation is no longer performed based on all yaw angular velocities between the second time point and the target time point, which avoids the situation where, when the accumulation time is too long, the yaw angular velocity accumulated in the initial part of the accumulation process is collected too early, the real-time performance of the yaw angular velocity accumulated in the initial part of the accumulation process is poor, and the accuracy of the accumulated yaw angular velocity is low, resulting in a low accuracy of the yaw angular velocity zero drift value determined based on the accumulation result of the yaw angular velocity, thereby improving the accuracy of the determined yaw angular velocity zero drift value.

[0046] In some embodiments, when the duration between the target time point and the second time point is not greater than the second duration and not less than the fourth duration, the target time period may be determined to be the period between the target time point and the second time point; wherein the fourth duration is less than the second duration, for example, the fourth duration is 3 seconds. Accordingly, if the duration between the target time point and the second time point is less than the fourth duration, the yaw angular velocity collected between the target time point and the second time point is discarded, and the yaw angular velocity zero drift value of the rear axle of the ego vehicle when the ego vehicle was in a stationary state the last time is obtained as the yaw angular velocity zero drift value of the rear axle of the ego vehicle at the target time point.

[0047] Similarly, when the duration between the target time point and the second time point is greater than the second time point and the determined third time point is less than the fourth time point, the time period with the target time point as the end time point and the duration of the fourth time period can be obtained as the second time period, and the average yaw angular velocity of the vehicle in the second time period is calculated as the yaw angular velocity zero drift value of the rear axle at the target time point.

[0048] Thus, the situation that the calculated yaw rate zero drift value is inaccurate due to the accumulation time being too short and the accumulated yaw rate being too small is avoided, thereby improving the accuracy of the determined yaw rate zero drift value.

[0049] In some embodiments, S110 may include: if the motion state information indicates that the ego vehicle is in a motion state at the target time point, obtaining the last static yaw angular velocity zero drift value of the rear axle before the ego vehicle enters a motion state from a static state, as the yaw angular velocity zero drift value of the rear axle at the target time point; the static yaw angular velocity zero drift value is the yaw angular velocity zero drift value of the rear axle when the ego vehicle is in a static state.

[0050] Among them, when the vehicle is in a stationary state, the process of determining the stationary yaw angular velocity zero drift value of the rear axle is as described above and will not be repeated here.

[0051] That is to say, when the vehicle changes from a stationary state to a moving state, the yaw rate zero drift value is the last yaw rate zero drift value output in the stationary state, and during the movement, the yaw rate zero drift value remains unchanged.

[0052] S120, determining a target positioning parameter of the rear axle at the target time point according to the yaw angular velocity zero drift value of the rear axle at the target time point.

[0053] In this embodiment, the positioning parameters may include the heading angle, coordinates (the coordinates may be coordinates in the world coordinate system or in the SL coordinate system) and yaw rate zero drift value of the rear axle, etc. The target positioning parameters refer to the positioning parameters of the rear axle at the target time point.

[0054] That is to say, the ego vehicle positions itself according to the yaw angular velocity zero drift value of the rear axle at the target time point, so as to determine the positioning parameters of the ego vehicle at the target time point as the target positioning parameters.

[0055] In this embodiment, the yaw velocity zero drift value of the rear axle of the own vehicle at the target time point is determined based on the yaw velocity of the rear axle of the own vehicle and the motion state information of the own vehicle at the target time point. The yaw velocity zero drift value of the rear axle is consistent with the motion state of the vehicle and is no longer a pre-calibrated fixed yaw velocity zero drift value, so that the yaw velocity zero drift value determined in accordance with the method of the present application is more accurate, so that the target positioning parameters of the rear axle at the target time point are determined more accurately based on the yaw velocity zero drift value of the rear axle at the target time point, thereby improving the accuracy of vehicle positioning.

[0056] In some embodiments, Figure 3 As shown, S120 may include:

[0057] S210, obtaining initial positioning parameters of the rear axis at an initial time point.

[0058] The initial time point is before the target time point; the initial positioning parameters include the initial coordinates of the rear axle and the initial yaw angle. The initial positioning parameters refer to the positioning parameters of the rear axle at the initial time point.

[0059] For example, the initial time point may be the time point when the vehicle enters a moving state from a stationary state, at which time point the vehicle may determine the initial positioning parameters of the rear axle.

[0060] In some embodiments, the driving process of the vehicle is long, and the driving process of the vehicle can be divided into a positioning period according to a fixed duration (for example, 2 minutes). The end time point of each positioning period is used as the start time point of the next positioning period, and the initial time point is the start time point of the positioning period where the target time point is located.

[0061] S220: Determine a heading angle change of the rear axle in the second time period according to the yaw angular velocity of the rear axle in the second time period and the yaw angular velocity zero drift value of the rear axle in the second time period.

[0062] The second time period is a time period starting at the initial time point and ending at the target time point.

[0063] Generally speaking, the yaw rate of the gyroscope of the own vehicle is the yaw rate of the rear axle. Similarly, the yaw rate zero drift value of the gyroscope of the own vehicle is the yaw rate zero drift value of the rear axle.

[0064] That is to say, the second time period is constructed with the initial time point as the starting point and the target time point as the end point, and the yaw angular velocity of the vehicle in the second time period and the yaw angular velocity zero drift value of the vehicle in the second time period are counted; then, based on the yaw angular velocity of the vehicle in the second time period and the yaw angular velocity zero drift value of the vehicle in the second time period, the heading angle change of the vehicle in the second time period is determined.

[0065] Usually, when the vehicle is stationary, the yaw angle change dPhi of the vehicle is 0; when the vehicle is in motion, the yaw angle change dPhi of the vehicle is dPhi = (Yawr_IMU-Zos) / 180*pi*dt; wherein, Yawr_IMU is the yaw angular velocity within the differential interval dt, Zos is the yaw angular velocity zero drift value, pi is the pi, and the differential interval can be set based on demand, for example, 0.5s.

[0066] Based on the above, it can be known that the heading angle change in the second time period may include the heading angle change of the rear wheel in each differential interval in the second time period (the heading angle change in each differential interval is determined according to the aforementioned formula "dPhi = (Yawr_IMU-Zos) / 180*pi*dt").

[0067] S230: Determine a target heading angle of the rear axle at a target time point according to the heading angle change of the rear axle in the second period and the initial heading angle.

[0068] That is to say, based on the initial heading angle, the initial heading angle is updated according to the heading angle change in each differential interval in the second time period (updated according to the formula Phi = Phi + dPhi) to obtain the target yaw angle at the target time point - the heading angle obtained after the heading angle change in the last differential interval in the second time period is updated.

[0069] S240: Determine the target coordinates of the rear axle at the target time point according to the initial coordinates and the rear wheel speed of the vehicle in the second time period.

[0070] That is to say, the initial coordinates of the rear axle at the initial time point are taken as the starting point, and based on the rear wheel speed of the vehicle in the second time period, the target coordinates of the rear axle at the target time point are determined.

[0071] In some embodiments, S240 may include: determining the initial coordinates of the rear wheels of the vehicle at the initial time point based on the initial coordinates, the initial heading angle and the rear wheel track of the vehicle; determining the target coordinates of the rear wheels at the target time point based on the driving direction of the vehicle, the initial coordinates of the rear wheels, the rear wheel speed of the vehicle in the second time period and the change in heading angle; determining the target coordinates of the rear axle at the target time point based on the rear wheel target coordinates.

[0072] For example, Figure 4 As shown, the mass point (x, y) rotates counterclockwise around point O by an angle a, and the coordinates of the mass point become (x', y'). The polar coordinates before rotation are (rho, theta), and the polar coordinates after rotation are (rho, theta + a). At this time, formula 1 is satisfied, which is as follows:

[0073] x=rho*cos(theta)

[0074] y=rho*sin(theta)

[0075] x'=rho*cos(theta+a)=rho*cos(theta)*cos(a)–tho*sin(theta)*sin(a)

[0076] y'=rho*sin(theta+a)=rho*sin(theta)*cos(a)+rho*cos(theta)*sin(a)

[0077] x'=x*cos(a)–y*sin(a)

[0078] y'=x*sin(a)+y*cos(a)

[0079] Based on formula 1, it is determined that the rotation matrix of the particle from (x, y) to (x', y') satisfies the following formula:

[0080]

[0081] The initial coordinates of the rear axle of the vehicle are marked as [xc; yc], the rear wheel track of the vehicle is recorded as Dr, and the coordinates of the rear wheels of the vehicle in the vehicle coordinate system are [0, -Dr / 2], [0, Dr / 2] respectively. The rotation angle Phi, at this time, the initial coordinates of the rear wheels of the vehicle are determined to satisfy Formula 2, which is as follows:

[0082] rri=[xc;yc]+[cos(Phi)―sin(Phi); sin(Phi)cos(Phi)]*[0;―Dr / 2];

[0083] rli=[xc;yc]+[cos(Phi)―sin(Phi);sin(Phi)cos(Phi)]*[0;Dr / 2];

[0084] Among them, rri is the initial coordinate of the rear wheel of the right rear wheel, and rli is the initial coordinate of the rear wheel of the left rear wheel.

[0085] After obtaining the initial coordinates of the rear wheels, the target coordinates of the rear wheels at the target time point can be determined according to the driving direction of the vehicle, the initial coordinates of the rear wheels, the rear wheel speed of the vehicle in the second period, and the change in the heading angle.

[0086] In the present application, the rear wheel speed in the second time period may include the rear wheel speed of each differential interval of the rear wheel in the second time period. Similarly, the heading angle change may include the heading angle change of each differential interval of the rear wheel in the second time period (the heading angle change of each differential interval is determined according to the aforementioned formula "dPhi=(Yawr_IMU―Zos) / 180*pi*dt"). Therefore, during the driving process of the vehicle, for each differential interval, the heading angle update process is: Phi=Phi+dPhi. Based on this, according to Formula 3, the rear wheel coordinates of the rear wheel after each differential interval are determined. Formula 3 is as follows:

[0087] r=rri+[cos(Phi);sin(Phi)]*RRSpd*dt;

[0088] rl=rli+[cos(Phi);sin(Phi)]*RLSpd*dt

[0089] Among them, rr is the rear wheel coordinate of the right rear wheel, rl is the rear wheel coordinate of the left rear wheel, RLSpd is the rear wheel speed of the left rear wheel within the differential interval dt, RRSpd is the rear wheel speed of the right rear wheel within the differential interval dt, the rear wheel speed is positive when it is forward and negative when it is backward.

[0090] In this way, by traversing each differential interval in the second time period in chronological order, the rear wheel coordinates rr0 of the right rear wheel and the rear wheel coordinates rl0 of the left rear wheel at the target time point after the last differential interval can be obtained. The rear wheel coordinates rr0 of the right rear wheel and the rear wheel coordinates rl0 of the left rear wheel are used as the rear wheel target coordinates of the rear wheels at the target time point.

[0091] After that, the target coordinates of the rear axle at the target time point can be determined based on the target coordinates of the rear wheels.

[0092] Optionally, the target coordinates of the rear axle at the target time point are determined based on the rear wheel target coordinates, including: determining the first estimated coordinates of the rear axle at the target time point based on the rear wheel coordinates corresponding to the left rear wheel in the rear wheel target coordinates, the target heading angle, and the rear wheel track; determining the second estimated coordinates of the rear axle at the target time point based on the rear wheel coordinates corresponding to the right rear wheel in the rear wheel target coordinates, the target heading angle, and the rear wheel track; determining the target coordinates of the rear axle at the target time point based on the second estimated coordinates and the second estimated coordinates.

[0093] Exemplarily, the rear wheel target coordinates determined in the present application include the rear wheel coordinates of the right rear wheel and the rear wheel coordinates of the left rear wheel. The first estimated coordinates and the second estimated coordinates may be calculated according to Formula 4, which is as follows:

[0094] crr=rr0―[cos(Phi)―sin(Phi); sin(Phi)cos(Phi)]*[―0;―Dr / 2];

[0095] crl=rl0―[cos(Phi)―sin(Phi); sin(Phi)cos(Phi)]*[―0; Dr / 2];

[0096] Among them, crr is the first estimated coordinate, and crl is the second estimated coordinate.

[0097] After obtaining the first estimated coordinates and the second estimated coordinates, the first estimated coordinates and the second estimated coordinates can be averaged to obtain the target coordinates of the rear axis at the target time point after the first estimated coordinates. That is, when the target coordinates of the rear axis at the target time point are expressed as (xc, yc), xc = (crr(1) + crl(1)) / 2; yc = (crr(2) + crl(2)) / 2.

[0098] S250, determining target positioning parameters of the rear axle at the target time point according to the target coordinates, the target heading angle, and the yaw angular velocity zero drift value of the rear axle at the target time point.

[0099] After obtaining the target coordinates, target heading angle and yaw angular velocity zero drift value of the rear axle at the target time point according to the aforementioned process, the target coordinates, target heading angle and yaw angular velocity zero drift value of the rear axle at the target time point are obtained as the target positioning parameters of the rear axle at the target time point.

[0100] For example, the vehicle positioning process is as follows: Figure 5As shown, the self-vehicle receives a gyroscope signal to determine the yaw angular velocity and the yaw angular velocity zero drift value according to the gyroscope signal, receives a gear signal, determines the driving direction of the self-vehicle according to the gear signal, receives a wheel speed pulse signal, determines the rear wheel speed according to the wheel speed pulse signal, and obtains initial positioning parameters (positioning parameters at an initial time point), and then, in combination with the aforementioned determined driving direction of the self-vehicle, rear wheel speed, initial positioning parameters, yaw angular velocity and yaw angular velocity zero drift value, determines the target positioning parameters, thereby realizing the positioning of the self-vehicle.

[0101] In this embodiment, the coordinates of the rear axle center of the vehicle are determined according to the rear wheel speed of the vehicle, thereby achieving the purpose of positioning the rear axle of the vehicle in combination with the movement of the vehicle and improving the positioning accuracy.

[0102] At the same time, the yaw angular velocity zero drift value determined by the method of the present application has a higher accuracy, so that the target coordinates and target yaw angle determined based on the yaw angular velocity zero drift value are more accurate, thereby improving the accuracy of the determined target positioning parameters.

[0103] See attached Figure 6 , Figure 6 The structure block diagram of a vehicle positioning device proposed in one embodiment of the present application is shown. For a vehicle, the device 800 includes:

[0104] A zero drift value determination module 810 is used to determine a zero drift value of the yaw angular velocity of the rear axle at a target time point according to the yaw angular velocity of the rear axle of the ego vehicle and the motion state information of the ego vehicle at the target time point;

[0105] The positioning module 820 is used to determine the target positioning parameters of the rear axle at the target time point according to the yaw angular velocity zero drift value of the rear axle at the target time point.

[0106] Optionally, the zero drift value determination module 810 is also used to determine the zero drift value of the yaw angular velocity of the rear axle at the target time point if the motion state information indicates that the vehicle is in a stationary state at the target time point and the duration between the target time point and the first time point exceeds the first duration, according to the yaw angular velocity of the rear axle between the second time point and the target time point; the first time point is the time point when the vehicle enters a stationary state; the second time point is the time point delayed by the first duration from the first time point.

[0107] Optionally, the zero drift value determination module 810 is also used to calculate the average value of the yaw angular velocity of the rear axle within the target time period as the yaw angular velocity zero drift value of the rear axle at the target time point; wherein, when the duration between the target time point and the second time point is not greater than the second duration, the target time period is the period between the target time point and the second time point; when the duration between the target time point and the second time point is greater than the second duration, the target time period is the period with the target time point as the end time point and a duration of a third duration, the third duration being the duration modulo the second duration based on the duration between the target time point and the second time point; the second duration is greater than the first duration.

[0108] Optionally, the zero drift value determination module 810 is further used to obtain the last stationary yaw angular velocity zero drift value of the rear axle before the vehicle enters the moving state from a stationary state if the motion state information indicates that the vehicle is in a moving state at the target time point, as the yaw angular velocity zero drift value of the rear axle at the target time point; the stationary yaw angular velocity zero drift value is the yaw angular velocity zero drift value of the rear axle when the vehicle is in a stationary state.

[0109] Optionally, the positioning module 820 is also used to obtain initial positioning parameters of the rear axle at an initial time point; the initial time point is before the target time point; the initial positioning parameters include the initial coordinates and initial heading angle of the rear axle; according to the yaw angular velocity of the rear axle in the second time period and the yaw angular velocity zero drift value of the rear axle in the second time period, determine the heading angle change of the rear axle in the second time period; wherein the second time period is a time period with the initial time point as the starting time point and the target time point as the ending time point; according to the heading angle change of the rear axle in the second time period and the initial heading angle, determine the target heading angle of the rear axle at the target time point; according to the initial coordinates and the rear wheel speed of the vehicle in the second time period, determine the target coordinates of the rear axle at the target time point; according to the target coordinates, the target heading angle and the yaw angular velocity zero drift value of the rear axle at the target time point, determine the target positioning parameters of the rear axle at the target time point.

[0110] Optionally, the positioning module 820 is further used to determine the initial coordinates of the rear wheels of the vehicle at an initial time point based on the initial coordinates, the initial heading angle and the rear wheel track of the vehicle; determine the target coordinates of the rear wheels at a target time point based on the driving direction of the vehicle, the initial coordinates of the rear wheels, the rear wheel speed of the vehicle in the second time period and the change in heading angle; and determine the target coordinates of the rear axle at the target time point based on the rear wheel target coordinates.

[0111] Optionally, the rear wheels include a left rear wheel and a right rear wheel; the positioning module 820 is further used to determine the first estimated coordinates of the rear axle at the target time point based on the rear wheel coordinates corresponding to the left rear wheel in the rear wheel target coordinates, the target heading angle and the rear wheel track; determine the second estimated coordinates of the rear axle at the target time point based on the rear wheel coordinates corresponding to the right rear wheel in the rear wheel target coordinates, the target heading angle and the rear wheel track; determine the target coordinates of the rear axle at the target time point based on the second estimated coordinates and the second estimated coordinates.

[0112] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here.

[0113] In addition, each function in each embodiment of the present application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The above integrated module can be implemented in the form of hardware or in the form of software function module.

[0114] On the other hand, the present application also provides a computer-readable storage medium, in which program code is stored. The program code can be called by a processor to execute the method described in the above method embodiment.

[0115] The computer readable storage medium may be an electronic memory such as a flash memory, an EEPROM (electrically erasable programmable read-only memory), an EPROM, a hard disk, or a cluster of ROMs. Optionally, the computer readable storage medium comprises a non-transitory computer-readable storage medium. The computer readable storage medium has storage space for program codes that execute any of the method steps in the above method. These program codes can be read from or written to one or more computer program products. The program code can be compressed, for example, in an appropriate form.

[0116] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A vehicle positioning method, characterized in that: The method comprises: Determining a yaw angular velocity zero drift value of the rear axle at the target time point according to the yaw angular velocity of the rear axle of the vehicle and the motion state information of the vehicle at the target time point; According to the yaw angular velocity zero drift value of the rear axle at the target time point, a target positioning parameter of the rear axle at the target time point is determined.

2. The method according to claim 1, characterized in that The determining, according to the yaw angular velocity of the rear axle of the vehicle and the motion state information of the vehicle at the target time point, the yaw angular velocity zero drift value of the rear axle at the target time point includes: If the motion state information indicates that the vehicle is in a stationary state at the target time point, and the duration between the target time point and the first time point exceeds the first duration, the yaw velocity zero drift value of the rear axle at the target time point is determined according to the yaw velocity of the rear axle between the second time point and the target time point; the first time point is the time point when the vehicle enters a stationary state; the second time point is a time point delayed by a first duration from the first time point as the starting point.

3. The method according to claim 2, characterized in that Determining the yaw angular velocity zero drift value of the rear axle at the target time point according to the yaw angular velocity of the rear axle between the second time point and the target time point includes: Calculating an average value of the yaw angular velocity of the rear axle during a target period of time as a yaw angular velocity zero drift value of the rear axle at the target time point; Among them, when the duration between the target time point and the second time point is not greater than the second duration, the target time period is the time period between the target time point and the second time point; when the duration between the target time point and the second time point is greater than the second duration, the target time period is a time period with the target time point as the end time point and a third duration, and the third duration is the duration based on the duration between the target time point and the second time point modulo the second duration; the second duration is greater than the first duration.

4. The method according to claim 1, characterized in that The determining, according to the yaw angular velocity of the rear axle of the vehicle and the motion state information of the vehicle at the target time point, the yaw angular velocity zero drift value of the rear axle at the target time point includes: If the motion state information indicates that the ego vehicle is in a motion state at the target time point, the last static yaw angular velocity zero drift value of the rear axle before the ego vehicle enters a motion state from a static state is obtained as the yaw angular velocity zero drift value of the rear axle at the target time point; the static yaw angular velocity zero drift value is the yaw angular velocity zero drift value of the rear axle when the ego vehicle is in a static state.

5. The method according to claim 1, characterized in that Determining the target positioning parameter of the rear axle at the target time point according to the yaw angular velocity zero drift value of the rear axle at the target time point includes: Acquire initial positioning parameters of the rear axle at an initial time point; the initial time point is before the target time point; the initial positioning parameters include initial coordinates and an initial heading angle of the rear axle; Determine the heading angle change of the rear axle in the second time period according to the yaw angular velocity of the rear axle in the second time period and the yaw angular velocity zero drift value of the rear axle in the second time period; wherein the second time period is a time period starting at the initial time point and ending at the target time point; Determining a target heading angle of the rear axle at the target time point according to the heading angle change of the rear axle during the second period and the initial heading angle; Determining the target coordinates of the rear axle at the target time point according to the initial coordinates and the rear wheel speed of the vehicle in the second time period; The target positioning parameters of the rear axle at the target time point are determined according to the target coordinates, the target heading angle, and the yaw angular velocity zero drift value of the rear axle at the target time point.

6. The method according to claim 5, characterized in that The step of determining the target coordinates of the rear axle at the target time point according to the initial coordinates and the rear wheel speed of the vehicle in the second time period includes: Determining the initial coordinates of the rear wheels of the vehicle at the initial time point according to the initial coordinates, the initial heading angle, and the rear wheel track of the vehicle; Determine the rear wheel target coordinates of the rear wheel at the target time point according to the driving direction of the vehicle, the initial coordinates of the rear wheels, the rear wheel speed of the vehicle in the second time period, and the change in the heading angle; According to the rear wheel target coordinates, the target coordinates of the rear axle at the target time point are determined.

7. The method according to claim 6, characterized in that The rear wheels include a left rear wheel and a right rear wheel; Determining the target coordinates of the rear axle at the target time point according to the rear wheel target coordinates includes: Determining a first estimated coordinate of the rear axle at the target time point according to the rear wheel coordinates corresponding to the left rear wheel in the rear wheel target coordinates, the target heading angle, and the rear wheel track; Determining a second estimated coordinate of the rear axle at the target time point according to the rear wheel coordinates corresponding to the right rear wheel in the rear wheel target coordinates, the target heading angle, and the rear wheel track; The target coordinates of the rear axle at the target time point are determined according to the second estimated coordinates and the second estimated coordinates.

8. A vehicle positioning device, characterized in that: The device comprises: a zero drift value determination module, configured to determine a zero drift value of the yaw angular velocity of the rear axle at the target time point according to the yaw angular velocity of the rear axle of the ego vehicle and the motion state information of the ego vehicle at the target time point; The positioning module is used to determine the target positioning parameters of the rear axle at the target time point according to the yaw angular velocity zero drift value of the rear axle at the target time point.

9. A vehicle, characterized in that: include: one or more processors; Memory; One or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the one or more processors, and the one or more applications are configured to execute the method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a program code executable by a processor, and when the program code is executed by the processor, the processor executes the method according to any one of claims 1 to 7.

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