Docking Method and Electronic Device for Tractor and Towed Target

Abstract

The present application discloses a docking method and an electronic device for a tractor and a towed target, belonging to the field of intelligent driving technology. A docking device and a target are provided on the towed target, and a detection device for detecting the target is provided on the tractor. The docking method includes: when the tractor reaches the docking starting position, acquiring a target ray detected by a radar and emitted; calculating an angular distribution state of the target ray relative to the central axis of the radar; and controlling the traveling direction of the tractor based on the angular distribution state to achieve docking of the tractor and the towed target. By acquiring the target ray detected by the radar provided on the tractor and emitted, the deflection angle of the tractor relative to the towed target can be determined through the included angle between the target ray and the central axis of the radar. By adjusting the movement direction of the tractor, the deflection angle can be adjusted, enabling the tractor and the towed target to be successfully docked.

Description

Technical Field

[0001] The present invention relates to the field of intelligent driving technology, and particularly to a method for docking a tractor and a towed target, and an electronic device. Background Art

[0002] When goods need to be transferred at airports or other places, trailers or pallets are required, and a tractor is used to dock with the trailer or pallet to achieve goods transfer. The process is as follows: The autonomous tractor reaches the docking position through an autonomous driving route. After reaching the docking position, for the markers on the trailer or pallet, the tractor performs positioning and automatic connection according to the markers on the trailer or pallet.

[0003] However, due to the relatively complex on-site environment, during the alignment process, due to inaccurate radar positioning of the tractor, walking accuracy of the tractor, noise of the markers caused by the on-site environment, and other reasons, the tractor may deviate from the preset docking starting position when reaching the docking starting position, resulting in possible deviation problems during the alignment process.

[0004] Therefore, how to accurately dock the tractor and the towed target has become an urgent technical problem to be solved. Summary of the Invention

[0005] To solve the technical problem of how to accurately dock the tractor and the towed target in the above background art, the present application proposes a method for docking a tractor and a towed target, and an electronic device.

[0006] According to a first aspect, a method for docking a tractor and a towed target is provided. A docking device and a target are provided on the towed target, and a detection device for detecting the target is provided on the tractor. The docking method includes: when the tractor reaches the docking starting position, obtaining a target ray detected by the radar that detects the target; calculating an angular distribution state of the target ray relative to the radar central axis; and controlling the traveling direction of the tractor based on the angular distribution state to achieve docking of the tractor and the towed target.

[0007] Optionally, calculating the angular distribution state of the target ray relative to the radar central axis includes: respectively determining the numbers of each target ray; and calculating the angular distribution state based on the numbers of the target rays and preset angles corresponding to the numbers.

[0008] Optionally, controlling the traveling direction of the tractor based on the angular distribution state to achieve docking of the tractor and the towed target includes: comparing the angles between the target rays of the target on both sides of the axis and the axis; and controlling the tractor to turn towards the side with a smaller angle.

[0009] Optionally, comparing the angles between the target rays on both sides of the axis and the axis includes: determining whether the angular deviation on both sides of the axis is greater than a first preset value; when the angular deviation on both sides of the axis is greater than the first preset value, controlling the tractor to turn towards the side with a smaller angle.

[0010] Optionally, when the angular deviation on both sides of the axis is greater than the first preset value, determining whether the angular deviation is greater than a second preset value; when the angular deviation on both sides of the axis is greater than the second preset value, controlling the tractor to drive away from the docking starting position and re-planning the route to reach the docking starting position, where the first preset value is less than the second preset value.

[0011] Optionally, controlling the traveling direction of the tractor based on the angle distribution state includes: obtaining the traveling state of the tractor when the tractor reaches the docking starting position; determining the angle to be turned when the tractor reaches collinearity with the docking device based on the angle distribution state, where the tractor reaching collinearity with the docking device means that the tractor can complete docking after moving in a straight line along the connection line between the tractor and the docking device, and the angle to be turned is the included angle between the target direction and the direction of the tractor; adjusting the steering angle based on the traveling state to obtain the target steering angle; controlling the traveling direction of the tractor based on the target steering angle.

[0012] Optionally, the traveling state includes the traveling speed of the tractor; adjusting the steering angle based on the traveling state includes: correcting the angle to be turned according to the traveling speed to obtain the target steering angle, where as the traveling speed increases, the angle to be turned increases.

[0013] Optionally, adjusting the steering orientation angle based on the traveling state includes: obtaining the direction of the wheels in the traveling state; determining the target direction based on the angle to be turned and the direction of the tractor; using the included angle between the direction of the wheels and the target direction as the target steering angle.

[0014] Optionally, adjusting the steering orientation angle based on the traveling state further includes: obtaining N historical target positions of the docking device before the current moment and the observed position of the docking device at the current moment; determining the predicted position of the docking device at the current moment based on the N historical target positions; fusing the observed position and the predicted position to obtain the current target position; performing path planning based on the current target position.

[0015] According to another aspect of the present application, there is provided an electronic device, including a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete communication with each other through the communication bus. The memory is used to store computer programs; the processor is used to execute the docking method of the tractor and the towed target as described in any one of the above by running the computer programs stored on the memory.

[0016] In the present application, by acquiring the target rays detected by the radar installed on the tractor, the deflection angle of the tractor relative to the towed target can be determined through the angle between the target rays and the central axis of the radar. By adjusting the moving direction of the tractor, the deflection angle can be adjusted, enabling the tractor and the towed target to be successfully docked. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present invention and form a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0018] Figure 1 is a schematic diagram of an exemplary tractor and towed target in the related art;

[0019] Figure 2 is a schematic flowchart of an exemplary docking method of a tractor and a towed target according to an embodiment of the present invention;

[0020] Figure 3 is a schematic structural diagram of an exemplary electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] In order to have a clearer understanding of the technical features, objectives, and effects of the present invention, the specific embodiments of the present invention are now described with reference to the drawings. In the drawings, the same reference numerals represent components with the same or similar structures but the same functions.

[0022] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0023] As described in the background art of the present application, when goods need to be transferred at airports or other places, trailers or pallets are required, and a tractor is used to dock with the trailer or pallet to achieve goods transfer. The process is as follows: The autonomous tractor reaches the docking position through the autonomous driving route. After reaching the docking position, the tractor positions and automatically connects according to the identification marks on the trailer or pallet.

[0024] The process of the tractor docking with the towed target is completely different from the existing path planning for autonomous driving. The docking of the tractor with the towed target is based on fixed markers. The tractor is driven to a fixed point. For example, there is a hook on the trailer head and a docking device on the pallet. When the docking is completed, the hook needs to be hooked onto the docking device. Therefore, the docking accuracy may require the decimeter level or centimeter level, and the existing autonomous driving solutions cannot meet the current requirements.

[0025] The existing docking and positioning methods often adopt the positioning method of lidar. A lidar target is set on the towed target. By collecting the point cloud data of the target and the positional relationship between the target and the docking device, the position of the docking device is determined. However, due to the relatively complex on-site environment, especially for the lidar positioning method, there may be more influencing factors on-site. For example, the target may shake. There may be strong reflective objects around the target. For example, the reflective tape on the work clothes of on-site operators. If the operator approaches the lidar's field of view, the reflective strip may form target noise points. Or, when a person passes through between the tractor head and the trailer, it will block the target point, forming positioning data similar to the target while losing the real data, resulting in too large a positioning deviation, and further causing problems such as the tractor reaching a different position from the preset docking starting position at the docking starting position and possible deviations during the alignment process.

[0026] To solve the above problems, the embodiments of the present application provide a docking method for a tractor and a towed target, as Figure 1 shown. A docking device and a target 20 are provided on the towed target, and a detection device for detecting the target 20 is provided on the tractor. Referring to Figure 2 the step schematic diagram of the docking method shown, the docking method may include:

[0027] S10. When the tractor reaches the docking starting position, obtain the target ray emitted by the radar 10 that detects the target 20.

[0028] S20. Calculate the angular distribution state of the target ray relative to the central axis of the radar 10.

[0029] S30. Control the traveling direction of the tractor based on the angular distribution state to achieve the docking of the tractor with the towed target.

[0030] In this embodiment, by acquiring the target rays detected by the radar 10 provided on the tractor and detecting the target 20, the deflection angle of the tractor relative to the towed target can be determined through the angle between the target rays and the central axis of the radar 10. By adjusting the moving direction of the tractor, the deflection angle can be adjusted so that the tractor and the towed target can be successfully docked. Specifically, the radar 10 emits laser light towards the towed target. After detecting the target 20, the radar 10 receives the laser light emitted by the target 20. When the radar 10 is at position A, the angles between the detected target rays and the central axis of the radar 10 are θ1 and θ2 respectively. When the radar 10 is at position B, the angles between the target rays and the central axis of the radar 10 are θ3 and θ4 respectively. After obtaining the angle between the central axis of the radar 10 and the target rays, combined with the current position of the radar 10, that is, the position of the tractor, steering adjustment is made to ensure that the tractor can successfully dock with the docking device on the towed target. Through accurate angle detection and corresponding tractor adjustment, precise docking between the tractor and the towed target can be achieved.

[0031] As an exemplary embodiment, calculating the angular distribution state of the target rays relative to the central axis of the radar 10 includes: respectively determining the numbers of each of the target rays; calculating the angular distribution state based on the numbers of the target rays and the preset angles corresponding to the numbers. In this embodiment, as shown in Figure 1 When the radar 10 is at position B, the angle between the central axis of the radar 10 and the 25th target ray is θ4, and the angle between the central axis of the radar 10 and the 5th target ray is θ3. After obtaining the angles, the current position of the tractor relative to the towed target can be analyzed and determined. Taking Figure 1 as an example, when the tractor is at position B, it needs to be adjusted towards the position of the 5th target ray. It can be that during the movement of the tractor towards the 5th target ray, the radar 10 emits laser light in real time, and the angular distribution state is re-determined through the target rays at the newly detected positions in real time. Based on the new angular distribution state, the movement of the tractor is adjusted, and gradually adjusted until the precise docking between the tractor and the towed target is finally achieved.

[0032] Exemplarily, controlling the traveling direction of the tractor based on the angular distribution state to achieve docking between the tractor and the towed target includes: comparing the angles between the target rays of the target 20 on both sides of the axis and the axis; controlling the tractor to turn towards the side with a smaller angle. When adjusting the moving direction of the tractor, it can be achieved through the size of the angle between the target rays and the central axis of the radar 10. Taking the tractor at position B as an example, θ3 < θ4, then at this time, the tractor should be controlled to turn towards the direction of the target ray corresponding to θ3.

[0033] When the tractor reaches the docking starting point position, it is possible that due to an excessive deviation angle, even if the tractor is timely controlled to turn towards the side with a smaller included angle, the docking between the tractor and the towed target cannot be achieved. Therefore, after obtaining the included angle between the central axis of the radar 10 and the target ray, first determine whether the included angle can satisfy the tractor turning to a position where it can successfully dock with the towed target.

[0034] Exemplarily, comparing the angles between the target rays of the targets 20 on both sides of the axis and the axis includes: determining whether the angle deviation on both sides of the axis is greater than a first preset value; when the angle deviation on both sides of the axis is greater than the first preset value, controlling the tractor to turn towards the side with a smaller angle. Taking the tractor at position B as an example, after obtaining the included angles θ3 and θ4, determine whether the difference between θ3 and θ4 is less than the first preset value. When the difference between θ3 and θ4 is less than the first preset value, it indicates that when the tractor is at position B, it can achieve docking with the towed target through turning adjustment. At this moment, control the tractor to turn according to the current position of the tractor and θ3 and / or θ4.

[0035] When the difference between θ3 and θ4 is too large, exemplarily, when the angle deviation on both sides of the axis is greater than the first preset value, determine whether the angle deviation is greater than a second preset value; when the angle deviation on both sides of the axis is greater than the second preset value, control the tractor to drive away from the docking starting point position and re-plan the route to reach the docking starting point position, where the first preset value is less than the second preset value.

[0036] When the difference between θ3 and θ4 is greater than the first preset value, determine whether the difference between θ3 and θ4 is greater than the second preset value. When the difference between θ3 and θ4 is greater than the second preset value, it indicates that the deviation angle between the tractor and the towed target is too large at this time, and the docking between the tractor and the towed target cannot be achieved by turning. At this time, control the tractor to drive away from the current starting point position and readjust to a new starting point position for docking with the towed target. When the difference between θ3 and θ4 is less than the second preset value, control the tractor to turn towards the side with a smaller included angle.

[0037] Exemplarily, controlling the traveling direction of the tractor based on the angle distribution state includes: obtaining the traveling state of the tractor when the tractor reaches the docking starting point position; determining the angle to be turned when the tractor reaches collinear with the docking device based on the angle distribution state, where the tractor reaching collinear with the docking device means that the tractor can complete docking after moving in a straight line along the connection line between the tractor and the docking device, and the angle to be turned is the included angle between the target direction and the direction the tractor is facing; adjusting the turning angle based on the traveling state to obtain the target turning angle; controlling the traveling direction of the tractor based on the target turning angle.

[0038] After determining the turning direction of the tractor through the angular distribution state, the tractor can be controlled to perform corresponding movements. However, the movement of the tractor at the current moment may not be the direction to turn. Therefore, it is also necessary to obtain the driving state of the tractor at the docking starting point at the current moment. After determining the driving state and the angle to be turned of the tractor, the turning angle of the tractor is adjusted. Among them, the driving state of the tractor will affect the turning angle. When the driving state of the tractor includes the driving speed, the steering angle is adjusted according to the current driving speed of the tractor. The greater the driving speed of the tractor, the greater the angle to be turned of the tractor. After the adjustment is completed, the tractor is controlled to move to complete the docking of the tractor and the towed target.

[0039] After determining the angle to be turned of the tractor, it is also necessary to determine the direction of the wheels of the tractor at the current moment. The target direction in which the tractor should travel is determined by the angle to be turned and the direction of the wheels. After determining the target direction, the wheels need to turn from the current wheel direction to the target direction in order for the tractor to successfully dock with the towed target. Therefore, the included angle between the current direction of the wheels and the target direction is the direction in which the wheels should turn. After controlling the wheels of the tractor to turn through the included angle between the current direction of the wheels and the target direction, the tractor can be controlled to move to complete the docking with the towed target.

[0040] When adjusting the position of the tractor, it is also necessary to obtain the position of the docking device. The position of the docking device can be determined not only by the laser emitted by the radar 10, but also by obtaining N historical target positions and the observed position of the docking device at the current moment. Among them, the target position is the historical position of the docking device, and the observed position is the position of the docking device determined by the radar 10. The position of the docking device can predict the predicted position of the docking device at the current moment through N historical target positions. Fusing the predicted position and the observed position can reduce the error caused by the influence of accidental external factors and improve the accuracy of obtaining the position of the docking device at the current moment.

[0041] According to the second aspect of the present application, an electronic device is also proposed. Refer to Figure 3 As shown, it includes a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete communication with each other through the communication bus. The memory is used to store computer programs; the processor is used to execute the docking method of the tractor and the towed target described in any one of the above embodiments by running the computer programs stored on the memory.

[0042] Optionally, it further includes a memory and a bus. In addition, the electronic device may also include hardware required for other services. The memory may include a memory and a non-volatile memory, and provide instructions and data for the processor to execute. Exemplarily, the memory may be a high-speed random access memory (RAM), and the non-volatile memory may be at least one disk memory.

[0043] Among them, the bus is used to connect the processor, the memory and the network interface to each other. The bus may be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, an EISA (Extended Industry Standard Architecture) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For the sake of convenience of representation, Figure 3 only a bidirectional arrow is used in the figure, but this does not mean that there is only one bus or one type of bus.

[0044] In a feasible implementation manner of the above electronic device, the processor may first read the corresponding execution instructions from the non-volatile memory into the memory and then run, or may first obtain the corresponding execution instructions from other devices and then run. When the processor executes the execution instructions stored in the memory, it can implement any one of the above docking methods of the tractor and the towed target of the present disclosure.

[0045] Those skilled in the art can understand that the above docking method for the tractor and the towed target can be applied to a processor or implemented with the aid of a processor. Exemplarily, a processor is an integrated circuit chip with the ability to process signals. During the execution of the above docking method for the tractor and the towed target by the processor, each step of the above docking method for the tractor and the towed target can be completed by an integrated logic circuit in hardware form or an instruction in software form in the processor. Further, the above processor can be a general-purpose processor, such as a Central Processing Unit (CPU), a Network Processor (NP), a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, a microprocessor, and any other conventional processor.

[0046] So far, the technical solutions of the present disclosure have been described in combination with multiple foregoing embodiments. However, those skilled in the art can easily understand that the protection scope of the present disclosure is not limited to these specific embodiments. Without departing from the technical principle of the present disclosure, those skilled in the art can split and combine the technical solutions in the above various embodiments, and can also make equivalent changes or substitutions to relevant technical features. Any changes, equivalent substitutions, improvements, etc. made within the technical concept and / or technical principle of the present disclosure will fall within the protection scope of the present disclosure.

[0047] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0048] The above are only the embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims

1. A docking method for a tractor and a towed target, characterized in that A docking device and a target are provided on the towed target, and a detection device for detecting the target is provided on the tractor. The docking method includes: When the tractor reaches the docking starting position, obtain the target ray detected by the radar that detects the target. Calculate the angular distribution state of the target ray relative to the central axis of the radar. Control the traveling direction of the tractor based on the angular distribution state to achieve docking between the tractor and the towed target. The controlling the traveling direction of the tractor based on the angular distribution state includes: Obtain the traveling state of the tractor when the tractor reaches the docking starting position. Determine the angle to be turned when the tractor reaches collinearity with the docking device based on the angular distribution state, where the tractor reaching collinearity with the docking device means the tractor completes docking after moving in a straight line along the connection line between the tractor and the docking device, and the angle to be turned is the included angle between the target direction and the facing direction of the tractor. Adjust the steering angle based on the traveling state to obtain the target steering angle. Control the traveling direction of the tractor based on the target steering angle. The adjusting the steering angle based on the traveling state includes: Obtain the wheel facing direction in the traveling state. Determine the target direction based on the angle to be turned and the facing direction of the tractor. Take the included angle between the wheel facing direction and the target direction as the target steering angle. The adjusting the steering angle based on the traveling state further includes: Obtain N historical target positions of the docking device before the current moment and the observed position of the docking device at the current moment. Determine the predicted position of the docking device at the current moment based on the N historical target positions. Fuse the observed position and the predicted position to obtain the current target position. Perform path planning based on the current target position.

2. The docking method of the tractor and the towed target according to claim 1, characterized in that, The calculating the angular distribution state of the target ray relative to the central axis of the radar includes: Respectively determine the number of each target ray. Calculate the angular distribution state based on the number of the target ray and the preset angle corresponding to the number.

3. The docking method of the tractor and the towed target according to claim 1, characterized in that, The controlling the traveling direction of the tractor based on the angular distribution state to achieve docking between the tractor and the towed target includes: Compare the angles between the target rays of the target on both sides of the axis and the axis. Control the tractor to turn towards the side with a smaller angle.

4. The docking method of the tractor and the towed target according to claim 3, characterized in that, The comparing the angles between the target rays of the target on both sides of the axis and the axis includes: Judge whether the angular deviation on both sides of the axis is greater than a first preset value. When the angular deviation on both sides of the axis is greater than the first preset value, control the tractor to turn towards the side with a smaller angle.

5. The docking method of the tractor and the towed target according to claim 4, characterized in that, When the angular deviation on both sides of the axis is greater than the first preset value, judge whether the angular deviation is greater than a second preset value. When the angular deviation on both sides of the axis is greater than the second preset value, control the tractor to drive away from the docking starting position and re-plan the route to reach the docking starting position, where the first preset value is less than the second preset value.

6. The docking method of the tractor and the towed target according to claim 1, characterized in that The driving state includes the driving speed of the tractor; The adjusting the steering angle based on the driving state includes: Correct the to-be-steered angle according to the driving speed to obtain the target steering angle, where as the driving speed increases, the to-be-steered angle increases.

7. An electronic device, comprising a processor, a communication interface, a memory, and a communication bus, wherein, The processor, the communication interface, and the memory complete communication with each other through the communication bus, characterized in that The memory is used to store computer programs; The processor is used to execute the docking method of the tractor and the towed target according to any one of claims 1 to 6 by running the computer program stored on the memory.

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