Unmanned vehicle reversing control method and device, control equipment and computer program product

Abstract

The invention is suitable for the technical field of unmanned vehicle control, and provides an unmanned vehicle backing control method and device, control equipment and a computer program product, and the method comprises the steps: determining a position point on an extension line of a target line segment under the condition that the unmanned vehicle deviates from a target track and backs, and obtaining a target position point, the target line segment is a line segment corresponding to the distance between the center of a front axle and the center of a rear axle of the unmanned vehicle, and the extension direction of an extension line of the target line segment is a corresponding direction in which the center of the front axle points to the center of the rear axle; determining the distance between the target position point and the target track to obtain a transverse deviation; the steering angle of the unmanned vehicle is determined according to the transverse deviation, and backing control is conducted on the unmanned vehicle according to the steering angle. Through the method, the accuracy of reversing control of the unmanned vehicle can be improved.

Description

Technical Field

[0001] The present application belongs to the field of unmanned vehicle control technology, and in particular, relates to an unmanned vehicle reversing control method, device, control equipment, computer-readable storage medium and computer program product. Background Art

[0002] With the development of technology, automatically driven vehicles have emerged. These automatically driven vehicles are also called unmanned vehicles.

[0003] Before the unmanned vehicle drives, a target trajectory is usually set for the unmanned vehicle. However, during the driving process, the actual trajectory of the unmanned vehicle may deviate from the target trajectory. At this time, the steering angle of the unmanned vehicle needs to be adjusted to reduce the deviation between the actual trajectory of the unmanned vehicle and the target trajectory. For example, during the reversing process, the lateral deviation is obtained by calculating the horizontal distance between the actual position of the unmanned vehicle and the target trajectory (also called the reference path or the planned path), and then the steering angle of the unmanned vehicle is determined based on the lateral deviation, and finally the actual trajectory of the unmanned vehicle is adjusted based on the steering angle.

[0004] In the existing unmanned vehicle reversing control method, the lateral deviation of the unmanned vehicle may be calculated using the center of the front axle of the unmanned vehicle, or the center of the rear axle of the unmanned vehicle. However, no matter which method is used to calculate the lateral deviation, when the steering angle of the unmanned vehicle is calculated based on the lateral deviation and the steering angle is used to adjust the driving trajectory of the unmanned vehicle, its accuracy is low. Summary of the invention

[0005] The embodiments of the present application provide an unmanned vehicle reversing control method, apparatus, control device and computer program product, which can solve the problem of low accuracy of vehicle control caused by low accuracy of lateral deviation calculated during reversing.

[0006] In a first aspect, an embodiment of the present application provides a method for controlling a reversing of an unmanned vehicle, comprising:

[0007] When it is detected that the unmanned vehicle deviates from the target trajectory and reverses, a position point is determined on the extension line of the target line segment to obtain the target position point, wherein the target line segment is a line segment corresponding to the distance between the center of the front axle and the center of the rear axle of the unmanned vehicle, and the extension direction of the extension line of the target line segment is the direction corresponding to the center of the front axle pointing to the center of the rear axle;

[0008] Determine the distance between the target position point and the target trajectory to obtain a lateral deviation;

[0009] The steering angle of the unmanned vehicle is determined according to the lateral deviation, and the unmanned vehicle is controlled to reverse according to the steering angle.

[0010] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0011] In the embodiment of the present application, when it is detected that the unmanned vehicle deviates from the target trajectory and reverses, the target position point is determined on the extension line of the target line segment, and the lateral deviation of the unmanned vehicle is determined according to the target position point. Since the target line segment is the line segment corresponding to the distance between the center of the front axle and the center of the rear axle of the unmanned vehicle, the extension direction of the extension line of the target line segment is the direction corresponding to the direction from the center of the front axle to the center of the rear axle, that is, the extension direction is the same as the current moving direction of the unmanned vehicle. Therefore, the target position point determined according to the above method is equivalent to the lateral deviation determined according to the forward direction of the unmanned vehicle based on the Stanley algorithm when the unmanned vehicle is moving forward, and the control of the vehicle according to the Stanley algorithm has a smaller control deviation and higher robustness. That is, when the lateral deviation is determined by the above method, and the steering angle of the unmanned vehicle is determined according to the determined lateral deviation to control the unmanned vehicle, it is conducive to improving the accuracy of the determined lateral deviation, and then it is conducive to improving the accuracy of the reverse control of the unmanned vehicle.

[0012] In a second aspect, an embodiment of the present application provides a reversing control device for an unmanned vehicle, comprising:

[0013] A target position point determination module is used to determine a position point on the extension line of a target line segment to obtain a target position point when it is detected that the unmanned vehicle deviates from the target track and reverses, wherein the target line segment is a line segment corresponding to the distance between the center of the front axle and the center of the rear axle of the unmanned vehicle, and the extension direction of the extension line of the target line segment is the direction corresponding to the center of the front axle pointing to the center of the rear axle;

[0014] A lateral deviation determination module, used to determine the distance between the target position point and the target trajectory to obtain a lateral deviation;

[0015] A steering angle determination module is used to determine the steering angle of the unmanned vehicle according to the lateral deviation, and to perform reverse control on the unmanned vehicle according to the steering angle.

[0016] In a third aspect, an embodiment of the present application provides a control device, applied to a vehicle, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method described in the first aspect when executing the computer program.

[0017] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described in the first aspect is implemented.

[0018] In a fifth aspect, an embodiment of the present application provides a computer program product, which, when executed on a control device, enables the control device to execute the method described in the first aspect above.

[0019] It can be understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art.

[0021] Figure 1 This is a schematic diagram of the relationship between an unmanned vehicle and a target trajectory when reversing, provided by an embodiment of the present application;

[0022] Figure 2 It is a flowchart of a method for controlling a reversing of an unmanned vehicle provided in one embodiment of the present application;

[0023] Figure 3 is a schematic diagram of a lateral deviation provided by an embodiment of the present application;

[0024] Figure 4 is a schematic diagram of a target position point determined according to the wheelbase and the rear axle center provided by an embodiment of the present application;

[0025] Figure 5 is a schematic diagram of determining a target position point according to a reference position point provided by another embodiment of the present application;

[0026] Figure 6 It is a structural schematic diagram of a reversing control device for an unmanned vehicle provided by an embodiment of the present application;

[0027] Figure 7 It is a structural schematic diagram of a control device provided in another embodiment of the present application. DETAILED DESCRIPTION

[0028] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0029] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0030] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0031] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. appearing in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways.

[0032] During the control process of the unmanned vehicle, when it is detected that the actual trajectory of the unmanned vehicle (i.e., the actual driving trajectory) deviates from the target trajectory, the unmanned vehicle can adjust the actual trajectory of the unmanned vehicle by reversing and dynamically adjusting the steering angle to reduce the deviation between the adjusted actual trajectory and the target trajectory.

[0033] like Figure 1 As shown, the front direction of the unmanned vehicle 11 is The direction pointed to is, FF' is the front axle of the unmanned vehicle 11, G is the center of FF', RR' is the rear axle of the unmanned vehicle 11, and J is the center of RR'. Figure 1 It can be seen that there is a deviation between the current position of the unmanned vehicle 11 and the target trajectory 12. At this time, the unmanned vehicle 11 will reverse in the direction indicated by the "V". During the reverse process, the steering angle of the unmanned vehicle 11 is adjusted to reduce the deviation between the actual trajectory of the unmanned vehicle 11 and the target trajectory 21.

[0034] Before adjusting the steering angle, the lateral deviation between the unmanned vehicle 11 and the target track 12 is first determined, and then the adjusted steering angle is determined according to the lateral deviation.

[0035] In the forward driving scenario, the front axle center can be used as the vehicle reference point to calculate the lateral deviation between the unmanned vehicle and the target trajectory ( Figure 1GM line segment in the figure), and the Stanley algorithm is used to calculate the steering angle based on the lateral deviation. In practical applications, the steering angle calculated by this method can obtain a smaller control deviation and higher robustness. However, for reversing scenarios, due to kinematic differences, if the front axle center is still used as the vehicle reference point, control instability will occur. Therefore, Stanley's original paper and other related papers propose to use the rear axle center as the vehicle reference point to calculate the lateral deviation for reversing scenarios (such as Figure 1 When JK is used as the lateral deviation to calculate the steering angle, the control performance can be improved to a certain extent, but the overall robustness is still poor, and the control performance is sensitive to the control parameters (such as the steering angle).

[0036] In order to improve the robustness of an unmanned vehicle in achieving path following by adjusting the steering angle in a reversing scenario, an embodiment of the present application provides a reversing control method for an unmanned vehicle.

[0037] In the unmanned vehicle reversing control method, a position point is determined on the extension line from the center of the front axle of the unmanned vehicle to the center of the rear axle, and a lateral deviation is determined based on the position point and the center of the rear axle. Since the position point determined in the above manner is equivalent to the lateral deviation determined based on the forward direction of the unmanned vehicle when the unmanned vehicle is traveling forward, the accuracy of the determined lateral deviation is improved, thereby improving the accuracy of the subsequent control of the unmanned vehicle.

[0038] The unmanned vehicle reversing control method provided in the embodiment of the present application is described below with reference to the accompanying drawings.

[0039] Figure 2 A flow chart of a method for controlling the reversing of an unmanned vehicle provided in an embodiment of the present application is shown. The method can be applied to a controller of an unmanned vehicle, and is described in detail as follows:

[0040] S21, when it is detected that the unmanned vehicle deviates from the target trajectory and reverses, a position point is determined on the extension line of the target line segment to obtain the target position point, wherein the target line segment is a line segment corresponding to the distance between the front axle center and the rear axle center of the unmanned vehicle, and the extension direction of the extension line of the target line segment is the direction corresponding to the front axle center pointing to the rear axle center.

[0041] Among them, the target trajectory is the trajectory set in advance for the unmanned vehicle for the task before the unmanned vehicle performs the task. It usually includes position information and may also include control quantity information such as speed and acceleration.

[0042] Specifically, during the driving process of the unmanned vehicle in performing a task, it will detect in real time or at a fixed time whether its driving trajectory deviates from the target trajectory, such as by judging whether its current position is on the target trajectory. If so, it is determined that the unmanned vehicle has not deviated from the target trajectory at its current position. When it is determined that the position of the unmanned vehicle has not deviated from the target trajectory within a period of time, it indicates that the driving trajectory of the unmanned vehicle within this period of time has not deviated from the target trajectory.

[0043] In the embodiment of the present application, the speed of the unmanned vehicle on the longitudinal axis (the axis where the center of the rear axle points to the center of the front axle) can be used to determine whether the unmanned vehicle is reversing. For example, when the speed of the longitudinal axis is positive, the unmanned vehicle is determined to be moving forward, and when the speed of the longitudinal axis is negative, the unmanned vehicle is determined to be reversing. When it is detected that the unmanned vehicle deviates from the target trajectory, if the unmanned vehicle adjusts the driving trajectory of the unmanned vehicle by reversing, that is, when the deviation between the driving trajectory of the unmanned vehicle and the target trajectory is reduced by reversing, a position point is determined on the extension line from the center of the front axle of the unmanned vehicle to the center of the rear axle, so that the lateral deviation can be determined later based on the position point and the center of the rear axle.

[0044] S22, determining the distance between the target position point and the target trajectory to obtain a lateral deviation.

[0045] like Figure 3 As shown, the GJ line segment is the target line segment, the target position point determined on the extension line of the GJ line segment is G', a perpendicular line is drawn from G' to the target line segment 12, and the foot of the perpendicular is L, then LG' is the above-mentioned lateral deviation.

[0046] S23, determining a steering angle of the unmanned vehicle according to the lateral deviation, and performing reverse control on the unmanned vehicle according to the steering angle.

[0047] The steering angle here is equivalent to the steering angle of the unmanned vehicle's steering wheel. The steering angle is used to determine the steering angle of the unmanned vehicle's front wheels. When the steering angle of the front wheels changes, the driving trajectory of the unmanned vehicle in reverse will also change, thereby achieving reverse control of the unmanned vehicle.

[0048] Specifically, the correspondence between the lateral deviation and the steering angle can be preset, and after the lateral deviation is determined, the steering angle corresponding to the determined lateral deviation can be found according to the preset correspondence. Of course, the steering angle of the unmanned vehicle can also be determined according to the lateral deviation and other parameters (such as the heading angle of the unmanned vehicle), which is not limited here.

[0049] In the embodiment of the present application, when it is detected that the unmanned vehicle deviates from the target trajectory and reverses, the target position point is determined on the extension line of the target line segment, and the lateral deviation of the unmanned vehicle is determined according to the target position point. Since the target line segment is the line segment corresponding to the distance between the center of the front axle and the center of the rear axle of the unmanned vehicle, the extension direction of the extension line of the target line segment is the direction corresponding to the direction from the center of the front axle to the center of the rear axle, that is, the extension direction is the same as the current moving direction of the unmanned vehicle. Therefore, the target position point determined according to the above method is equivalent to the lateral deviation determined according to the forward direction of the unmanned vehicle based on the Stanley algorithm when the unmanned vehicle is moving forward, and the control of the vehicle according to the Stanley algorithm has a smaller control deviation and higher robustness. That is, when the lateral deviation is determined by the above method, and the steering angle of the unmanned vehicle is determined according to the determined lateral deviation to control the unmanned vehicle, it is conducive to improving the accuracy of the determined lateral deviation, and then it is conducive to improving the accuracy of the reverse control of the unmanned vehicle.

[0050] In some embodiments, the target position point may be determined by referring to the length of the target line segment. The above S21 determines a position point on the extension line of the target line segment. When the target position point is obtained, the following steps are included:

[0051] A position point is determined on the extension line of the target line segment according to the distance between the center of the front axle and the center of the rear axle to obtain the target position point.

[0052] Specifically, based on the position coordinates of the front axle center and the rear axle center, the distance between the front axle center and the rear axle center, i.e., the wheelbase, which is also the length of the target line segment mentioned above, is calculated, and then based on the length of the target line segment, the target position point is determined on the extension line of the target line segment.

[0053] For example, a position point (assuming it is the first position point) is determined between the center of the front axle and the center of the rear axle (including the center of the rear axle), and another position point (assuming it is the second position point) is determined after the first position point, so that the distance between the second position point and the first position point is equal to the product of the length of the target line segment and the first preset ratio value. In this case, the second position point is the above-mentioned target position point. The above-mentioned first preset ratio value is a rational number greater than 0, such as a fraction greater than 0 and less than 1, or an integer greater than 1, etc.

[0054] For another example, a position point (assuming it is the first position point) is determined after the rear axle center, and another position point (assuming it is the second position point) is determined after the first position point, so that the distance between the second position point and the first position point is equal to the second preset ratio value of the length of the target line segment. In this case, the second position point is the above-mentioned target position point. The above-mentioned first preset ratio value is a rational number greater than 0, such as a fraction greater than 0 and less than 1.

[0055] In the embodiment of the present application, since the target position point is determined on the extension line of the target line segment according to the distance between the center of the front axle and the center of the rear axle, and the distance between the center of the front axle and the center of the rear axle is the wheelbase, and the change in the wheelbase will affect the stability and handling of the vehicle, therefore, the target position point determined according to the above method is conducive to improving the accuracy of the obtained target position point.

[0056] In some embodiments, determining a position point on the extension line of the target line segment according to the distance between the center of the front axle and the center of the rear axle to obtain the target position point includes:

[0057] A position point whose distance from the center of the rear axle is equal to the distance between the center of the front axle and the center of the rear axle is determined on the extension line of the target line segment to obtain the target position point.

[0058] In the embodiment of the present application, the specific process of determining the target position point is similar to the specific process of determining the target position point according to the wheelbase, except that the distance between the target position point and the center of the rear axle is defined as being equal to the wheelbase. Figure 4 ,exist Figure 4 In the figure, the distance of line segment JG' is equal to the distance of line segment GJ, and the angle less than 90° formed by straight line CC' and straight line AA' is the steering angle, which has a corresponding relationship with the steering angle, and the steering angle also has a corresponding mapping relationship with the turning angles of the two front wheels of the unmanned vehicle, that is, after determining the steering angle, the corresponding steering angle can be determined, and then the turning angles corresponding to the two front wheels of the unmanned vehicle can be determined respectively according to the steering angle. Among them, straight line NG is perpendicular to straight line CC', straight line NG' is perpendicular to straight line DD', and the position of point N is the corresponding bend center of the unmanned vehicle. When the unmanned vehicle is controlled by the calculated steering angle, the unmanned vehicle will travel along the arc with the bend center as the center of the circle. Since the distance of line segment JG' is equal to the distance of line segment GJ, determining the lateral distance (i.e., line segment LG') according to G' is equivalent to determining the lateral distance according to the Stanley algorithm. Therefore, when determining the target position point according to the above method, it is beneficial to improve the accuracy of the lateral deviation determined subsequently according to the target position point.

[0059] Considering that the steering angles determined by different lateral deviations are usually different, and different steering angles will also have different control effects on the unmanned vehicle, for example, the control effect on the unmanned vehicle may be underdamped or overdamped, therefore, it is necessary to select the position point as the target position point in combination with the control effect on the unmanned vehicle. Among them, the underdamped phenomenon means that the unmanned vehicle can quickly reduce the deviation from the target trajectory, but there is an oscillation phenomenon, while the overdamped phenomenon means that the unmanned vehicle can relatively slowly reduce the deviation from the target trajectory, but there is almost no oscillation phenomenon.

[0060] That is, in some embodiments, the above S21 determines a position point on the extension line of the target line segment to obtain the target position point, including:

[0061] A1. Determine a position point on the extension line of the target line segment whose distance from the center of the rear axle is equal to the distance between the center of the front axle and the center of the rear axle to obtain a reference position point.

[0062] Specifically, the process of determining the reference position point is similar to the process of determining the target position point described above. It is only necessary to ensure that the distance between the reference position point and the center of the rear axle is equal to the wheelbase, which will not be described in detail here.

[0063] A2. Determine the target location point according to the type of the object on the unmanned vehicle and the reference location point.

[0064] Among them, the type of the above-mentioned item is used to indicate the type of the item, such as the type corresponding to a ceramic plate is ceramic, and the type corresponding to a glass cup is glass. Of course, the type of the item can also be used to indicate whether the item is a fragile item, among which ceramic and glass products are both fragile items.

[0065] Specifically, it is possible to first determine whether there is an object on the unmanned vehicle. If so, determine the type of the object, and then determine which type of control is suitable for the unmanned vehicle based on the type of the object. For example, determine whether it is suitable for control that quickly reduces the deviation from the target trajectory but has oscillations, or is suitable for control that slowly reduces the deviation from the target trajectory but has no oscillations, or is suitable for other types of control, etc.

[0066] Since the lateral deviations determined by different target position points are usually different, and when the lateral deviations are different, the steering angles determined according to the lateral deviations are also usually different, therefore, the determination of the target position point will affect the control effect of the unmanned vehicle. For example, when the unmanned vehicle is controlled according to the steering angles determined by different target position points, underdamping or overdamping may occur. When underdamping occurs, the oscillation trajectory may cause the position of the items on the unmanned vehicle to change, and may also cause the items to fall. Since the distance between the reference position point and the center of the rear axle is equal to the wheelbase of the unmanned vehicle, that is, when the lateral deviation is determined according to the reference position point and the steering angle determined by the lateral deviation is controlled, a smaller control deviation and higher robustness can be obtained. Therefore, in the embodiment of the present application, the above-mentioned target position point is determined according to the type of items on the unmanned vehicle and the reference position point, which is conducive to improving the matching degree between the determined target position point and the control effect and the transportation requirements of the type of items.

[0067] In some embodiments, considering that the lateral deviation can be infinite, but the range of the steering angle is [0°, 90°], that is, the lateral deviation and the steering angle are positively correlated, but not proportional. Therefore, when the lateral deviation is large, when the steering angle is determined according to the lateral deviation and the lateral deviation between the unmanned vehicle and the target trajectory is reduced by using the steering angle, the convergence speed is slow. When the convergence speed is slow, the unmanned vehicle is less bumpy and is not easy to cause damage to the items on the unmanned vehicle. Therefore, when the items on the unmanned vehicle are easily damaged, a position point where a large lateral deviation can be determined can be selected as the target position point. At this time, the above A2 includes:

[0068] When the type of the item on the unmanned vehicle indicates that the item is a fragile item, the target position point is determined on the extension line of the target line segment, and the distance between the target position point and the target trajectory is greater than the distance between the reference position point and the target trajectory.

[0069] Specifically, since the distance between the target position point and the target trajectory is greater than the distance between the reference position point and the target trajectory, when the steering angle is determined based on the larger lateral deviation and the unmanned vehicle is controlled, the convergence speed of the lateral deviation of the unmanned vehicle is slow (i.e., the speed of decreasing to 0 is slow), which is equivalent to the over-damping situation. In addition, since the convergence speed of the lateral deviation of the unmanned vehicle is slow, it is equivalent to the state of the unmanned vehicle changing at a lower frequency, and the unmanned vehicle with a lower frequency of state change also generates less vibration to the items on the vehicle, which is conducive to reducing the damage to the items on the vehicle caused by the state change.

[0070] Optionally, before determining the target position point, it can be determined whether the reference position point and the unmanned vehicle are on the same side of the target track. If not, the target position point is determined after the reference position point. If so, a position point symmetrical to the reference track can be determined on the other side of the target track, and the target position point is determined after the position point, so that the distance between the target position point and the target track is greater than the distance between the reference position point and the target track. Figure 5 As shown, L is the reference position point, and a position point "P" symmetrical to L is determined on the other side of the target trajectory 12 (i.e., the BB' straight line). When a larger lateral deviation needs to be determined, a position point can be determined after "P" (i.e., along the positive direction of the X-axis) as the above-mentioned target position point.

[0071] The above describes how to determine the target location when the item is fragile. The following describes how to determine the target location when the item is not fragile.

[0072] In some embodiments, the above A2 includes:

[0073] When the type of the item on the unmanned vehicle indicates that the item is not a fragile item, the target position point is determined on the extension line of the target line segment, and the distance between the target position point and the target trajectory is not greater than the distance between the reference position point and the target trajectory.

[0074] Specifically, when the distance between the target position point and the target trajectory is not greater than the distance between the reference position point and the target trajectory, and the steering angle is determined based on a smaller lateral deviation and the unmanned vehicle is controlled, the convergence speed of the lateral deviation of the unmanned vehicle is faster (i.e., the speed of decreasing to 0 is faster), which is equivalent to the underdamped situation. In addition, since the items on the unmanned vehicle are not easily damaged, even if the unmanned vehicle generates some vibrations during the convergence process, it is difficult to damage the items. Therefore, the target position point is determined by the above method, and the steering angle is determined based on the lateral deviation corresponding to the target position point (i.e., the distance between the target position point and the target trajectory), which is conducive to improving the convergence speed of the lateral deviation of the unmanned vehicle.

[0075] Optionally, before determining the target position point, a position point symmetrical to the reference trajectory can be determined on the other side of the target trajectory, and a position point between the position point and the reference position point can be selected as the target position point so that the distance between the target position point and the target trajectory is not greater than the distance between the reference position point and the target trajectory.

[0076] In some embodiments, the target location point may also be determined in combination with the urgency of the task. In this case, the above step A2 specifically includes: determining the above target location point according to the type of items on the unmanned vehicle, the urgency of the task currently being performed by the unmanned vehicle, and the reference location point.

[0077] Specifically, at least three levels are divided in advance according to the type of items, and different levels correspond to different degrees of vulnerability. When it is necessary to determine the target location point, if it is determined that the task currently performed by the unmanned vehicle is in an urgent degree, the corresponding degree of vulnerability is determined according to the type of items on the unmanned vehicle. If its degree of vulnerability is not the highest, a location point with a smaller distance from the target trajectory can be selected as the target location point, so that the distance between the target location point and the target trajectory is not greater than the distance between the reference location point and the target trajectory. However, if it is determined that the task currently performed by the unmanned vehicle is in an urgent degree, and the degree of vulnerability of the type of items on the unmanned vehicle is the highest, a location point with a larger distance from the target trajectory can be selected as the target location point, so that the distance between the target location point and the target trajectory is greater than the distance between the reference location point and the target trajectory.

[0078] Since the urgency of the task currently being performed by the unmanned vehicle is also taken into consideration when determining the target location point, this is beneficial to improving the accuracy of the determined target location point.

[0079] In some embodiments, considering that the target position point is selected at a position behind the unmanned vehicle, the sign of the steering angle corresponding to the target position point is opposite to the sign of the steering angle corresponding to the center of the front axle, so a sign inversion operation is required when determining the steering angle, that is, the above S23 includes:

[0080] B1. Determine a candidate steering angle based on the above lateral deviation.

[0081] Specifically, the lateral deviation and the candidate steering angle can be pre-set to be positively correlated. After the lateral deviation is determined according to the above method, the subsequent steering angle corresponding to the determined lateral deviation can be found according to the positive correlation. Of course, the heading deviation of the unmanned vehicle can also be calculated, and then the candidate steering angle is calculated based on the heading deviation and the lateral deviation, which is not limited here.

[0082] B2. Reverse the sign of the candidate steering angle to obtain the steering angle of the unmanned vehicle.

[0083] refer to Figure 4 , assuming that the angle less than 90° between the straight line DD' and the straight line AA' is the first angle, and the angle less than 90° between the straight line CC' and the straight line AA' is the second angle, then the sign of the first angle is opposite to the sign of the second angle. Therefore, after the candidate steering angle is calculated in step B1, the sign of the candidate steering angle is inverted, and the obtained angle is used as the steering angle of the unmanned vehicle.

[0084] In the embodiment of the present application, considering that the target position point is selected at the position behind the unmanned vehicle, and the sign of the steering angle at the target position point is opposite to the sign of the steering angle at the center of the front axle, therefore, the above processing is helpful to improve the accuracy of the final steering angle.

[0085] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0086] Corresponding to the unmanned vehicle reversing control method described in the above embodiment, Figure 6 A structural block diagram of the unmanned vehicle reversing control device provided in an embodiment of the present application is shown. For ease of explanation, only the parts related to the embodiment of the present application are shown.

[0087] Reference Figure 6 The unmanned vehicle reversing control device 6 is applied to a vehicle and includes:

[0088] The target position point determination module 61 is used to determine a position point on the extension line of the target line segment to obtain the target position point when it is detected that the unmanned vehicle deviates from the target trajectory and reverses, wherein the above-mentioned target line segment is the line segment corresponding to the distance between the front axle center and the rear axle center of the above-mentioned unmanned vehicle, and the extension direction of the extension line of the above-mentioned target line segment is the direction corresponding to the front axle center pointing to the rear axle center.

[0089] The lateral deviation determination module 62 is used to determine the distance between the target position point and the target trajectory to obtain the lateral deviation.

[0090] The steering angle determination module 63 is used to determine the steering angle of the unmanned vehicle according to the lateral deviation, and perform reverse control on the unmanned vehicle according to the steering angle.

[0091] In the embodiment of the present application, when it is detected that the unmanned vehicle deviates from the target trajectory and reverses, the target position point is determined on the extension line of the target line segment, and the lateral deviation of the unmanned vehicle is determined according to the target position point. Since the target line segment is the line segment corresponding to the distance between the center of the front axle and the center of the rear axle of the unmanned vehicle, the extension direction of the extension line of the target line segment is the direction corresponding to the direction from the center of the front axle to the center of the rear axle, that is, the extension direction is the same as the current moving direction of the unmanned vehicle. Therefore, the target position point determined according to the above method is equivalent to the lateral deviation determined according to the forward direction of the unmanned vehicle based on the Stanley algorithm when the unmanned vehicle is moving forward, and the control of the vehicle according to the Stanley algorithm has a smaller control deviation and higher robustness. That is, when the lateral deviation is determined by the above method, and the steering angle of the unmanned vehicle is determined according to the determined lateral deviation to control the unmanned vehicle, it is conducive to improving the accuracy of the determined lateral deviation, and then it is conducive to improving the accuracy of the reverse control of the unmanned vehicle.

[0092] In some embodiments, the target position point determination module 61 determines a position point on the extension line of the target line segment. When obtaining the target position point, it is specifically used to:

[0093] A position point is determined on the extension line of the target line segment according to the distance between the center of the front axle and the center of the rear axle to obtain the target position point.

[0094] In some embodiments, determining a position point on the extension line of the target line segment according to the distance between the center of the front axle and the center of the rear axle to obtain the target position point includes:

[0095] A position point whose distance from the center of the rear axle is equal to the distance between the center of the front axle and the center of the rear axle is determined on the extension line of the target line segment to obtain the target position point.

[0096] In some embodiments, the target position point determination module 61 determines a position point on the extension line of the target line segment, and when obtaining the target position point, specifically includes:

[0097] A reference position point determination unit, configured to determine a position point on the extension line of the target line segment whose distance from the center of the rear axle is equal to the distance between the center of the front axle and the center of the rear axle, to obtain a reference position point;

[0098] The target position point determination unit is used to determine the target position point according to the type of the object on the unmanned vehicle and the reference position point.

[0099] In some embodiments, the target location point determination unit is specifically used to:

[0100] When the type of the item on the unmanned vehicle indicates that the item is a fragile item, the target position point is determined on the extension line of the target line segment, and the distance between the target position point and the target trajectory is greater than the distance between the reference position point and the target trajectory.

[0101] Optionally, before determining the target position point, it can be determined whether the reference position point and the unmanned vehicle are on the same side of the target trajectory. If not, the target position point is determined after the reference position point. If so, a position point symmetrical to the reference trajectory can be determined on the other side of the target trajectory, and the target position point is determined after this position point, so that the distance between the target position point and the target trajectory is greater than the distance between the reference position point and the target trajectory.

[0102] In some embodiments, the target location point determination unit is specifically used to:

[0103] When the type of the item on the unmanned vehicle indicates that the item is not a fragile item, the target position point is determined on the extension line of the target line segment, and the distance between the target position point and the target trajectory is not greater than the distance between the reference position point and the target trajectory.

[0104] Optionally, before determining the target position point, a position point symmetrical to the reference trajectory can be determined on the other side of the target trajectory, and a position point between the position point and the reference position point can be selected as the target position point so that the distance between the target position point and the target trajectory is not greater than the distance between the reference position point and the target trajectory.

[0105] In some embodiments, the target location point can also be determined in combination with the urgency of the task. In this case, the target location point determination unit is specifically used to determine the target location point according to the type of items on the unmanned vehicle, the urgency of the task currently performed by the unmanned vehicle, and the reference location point.

[0106] In some embodiments, when adjusting the steering angle of the unmanned vehicle according to the lateral deviation, the steering angle determination module 63 is specifically used to:

[0107] determining a candidate steering angle based on the lateral deviation;

[0108] The signs of the candidate steering angles are inverted to obtain the steering angle of the unmanned vehicle.

[0109] It should be noted that the information interaction, execution process, etc. between the above-mentioned devices / units are based on the same concept as the method embodiment of the present application. Their specific functions and technical effects can be found in the method embodiment part and will not be repeated here.

[0110] Figure 7 This is a schematic diagram of the structure of a control device provided in one embodiment of the present application. Figure 7 As shown, the control device 7 of this embodiment includes: at least one processor 70 ( Figure 7 Only one processor is shown in the figure), a memory 71, and a computer program 72 stored in the above-mentioned memory 71 and executable on at least one of the above-mentioned processors 70, wherein the above-mentioned processor 70 implements the steps in any of the above-mentioned method embodiments when executing the above-mentioned computer program 72.

[0111] The control device 7 is applied to a vehicle, and the control device may include but is not limited to a processor 70 and a memory 71. Those skilled in the art will appreciate that Figure 7 It is only an example of the control device 7 and does not constitute a limitation on the control device 7. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, it may also include input and output devices, network access devices, etc.

[0112] The processor 70 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.

[0113] In some embodiments, the memory 71 may be an internal storage unit of the control device 7, such as a hard disk or memory of the control device 7. In other embodiments, the memory 71 may also be an external storage device of the control device 7, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the control device 7. Further, the memory 71 may also include both an internal storage unit and an external storage device of the control device 7. The memory 71 is used to store an operating system, an application program, a boot loader (BootLoader), data, and other programs, such as the program code of the computer program. The memory 71 may also be used to temporarily store data that has been output or is to be output.

[0114] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0115] An embodiment of the present application also provides a network device, which includes: at least one processor, a memory, and a computer program stored in the memory and executable on the at least one processor, wherein the processor implements the steps in any of the above-mentioned method embodiments when executing the computer program.

[0116] An embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps in the above-mentioned method embodiments can be implemented.

[0117] An embodiment of the present application provides a computer program product. When the computer program product runs on a control device, the control device can implement the steps in the above-mentioned method embodiments when the computer program product is executed.

[0118] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, which can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium can at least include: any entity or device that can carry the computer program code to the camera / control device, recording medium, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, RandomAccess Memory), electric carrier signal, telecommunication signal and software distribution medium. For example, a USB flash drive, a mobile hard disk, a magnetic disk or an optical disk. In some jurisdictions, according to legislation and patent practice, computer-readable media cannot be electric carrier signals and telecommunication signals.

[0119] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0120] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0121] In the embodiments provided in the present application, it should be understood that the disclosed devices / network equipment and methods can be implemented in other ways. For example, the device / network equipment embodiments described above are merely schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0122] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0123] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for controlling the reversing of an unmanned vehicle, characterized in that: include: When it is detected that the unmanned vehicle deviates from the target trajectory and reverses, a position point is determined on the extension line of the target line segment to obtain the target position point, wherein the target line segment is a line segment corresponding to the distance between the center of the front axle and the center of the rear axle of the unmanned vehicle, and the extension direction of the extension line of the target line segment is the direction corresponding to the center of the front axle pointing to the center of the rear axle; Determine the distance between the target position point and the target trajectory to obtain a lateral deviation; The steering angle of the unmanned vehicle is determined according to the lateral deviation, and the unmanned vehicle is controlled to reverse according to the steering angle.

2. The unmanned vehicle reversing control method according to claim 1, characterized in that: Determining a position point on the extension line of the target line segment to obtain the target position point includes: A position point is determined on the extension line of the target line segment according to the distance between the center of the front axle and the center of the rear axle to obtain a target position point.

3. The unmanned vehicle reversing control method according to claim 2, characterized in that: Determining a position point on the extension line of the target line segment according to the distance between the center of the front axle and the center of the rear axle to obtain the target position point includes: A position point whose distance from the center of the rear axle is equal to the distance between the center of the front axle and the center of the rear axle is determined on the extension line of the target line segment to obtain the target position point.

4. The unmanned vehicle reversing control method according to claim 1, characterized in that: Determining a position point on the extension line of the target line segment to obtain the target position point includes: Determine a position point on the extension line of the target line segment whose distance from the center of the rear axle is equal to the distance between the center of the front axle and the center of the rear axle, to obtain a reference position point; The target location point is determined according to the type of the object on the unmanned vehicle and the reference location point.

5. The unmanned vehicle reversing control method according to claim 4, characterized in that: The step of determining the target location point according to the type of the object on the unmanned vehicle and the reference location point includes: When the type of the item on the unmanned vehicle indicates that the item is a fragile item, the target position point is determined on the extension line of the target line segment, and the distance between the target position point and the target trajectory is greater than the distance between the reference position point and the target trajectory.

6. The unmanned vehicle reversing control method according to claim 4, characterized in that: The step of determining the target location point according to the type of the object on the unmanned vehicle and the reference location point includes: When the type of the item on the unmanned vehicle indicates that the item is not a fragile item, the target position point is determined on the extension line of the target line segment, and the distance between the target position point and the target trajectory is not greater than the distance between the reference position point and the target trajectory.

7. The unmanned vehicle reversing control method according to any one of claims 1 to 6, characterized in that: The step of adjusting the steering angle of the unmanned vehicle according to the lateral deviation comprises: determining a candidate steering angle based on the lateral deviation; The sign of the candidate steering angle is inverted to obtain the steering angle of the unmanned vehicle.

8. A reversing control device for an unmanned vehicle, characterized in that: include: A target position point determination module is used to determine a position point on the extension line of a target line segment to obtain a target position point when it is detected that the unmanned vehicle deviates from the target track and reverses, wherein the target line segment is a line segment corresponding to the distance between the center of the front axle and the center of the rear axle of the unmanned vehicle, and the extension direction of the extension line of the target line segment is the direction corresponding to the center of the front axle pointing to the center of the rear axle; A lateral deviation determination module, used to determine the distance between the target position point and the target trajectory to obtain a lateral deviation; A steering angle determination module is used to determine the steering angle of the unmanned vehicle according to the lateral deviation, and to perform reverse control on the unmanned vehicle according to the steering angle.

9. A control device, applied to a vehicle, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

11. A computer program product, characterized in that The invention comprises a computer program, which, when executed, enables the method according to any one of claims 1 to 7 to be performed.

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