Vehicle body region detection method, towing vehicle and towing vehicle obstacle avoidance system

Abstract

The embodiment of the application relates to the technical field of unmanned driving, and discloses a vehicle body region detection method, a tractor and a tractor obstacle avoidance system. The method comprises the following steps: obtaining three-dimensional position information of a crosspiece through a laser radar; calculating a region position of a flat car group in driving according to the three-dimensional position information of the crosspiece, the length of the flat car group, external parameter information of the laser radar and width information of the crosspiece; and combining a vehicle body range of the tractor with a position region of the flat car group to obtain a vehicle body region. The application does not need to arrange sensors on the flat car, does not limit the number of the flat car, and has high sensing accuracy.

Description

Technical Field

[0001] This application relates to the field of autonomous driving technology, and in particular to a vehicle body area detection method, a tractor and a tractor obstacle avoidance system. Background Technology

[0002] Multi-section flatbed tractors are widely used in manufacturing plants, and there are also a large number of baggage handling vehicles in airports. Moreover, many tractors in factories and airports are currently driverless.

[0003] The tractor unit pulls a flatbed trailer assembly, which consists of multiple flatbed trailers of the same specifications connected together. The flatbed trailer assembly and the tractor unit are non-rigidly connected via connecting shafts. When the vehicle is moving, it does not travel in a straight line. For an unmanned tractor unit to achieve obstacle avoidance or collision avoidance, it generally needs to accurately know the overall position of the entire vehicle (including the tractor unit and the last flatbed trailer in the assembly). Flatbed trailers are generally divided into those with and without tracks. Unmanned tractor units typically use flatbed trailers with tracks, meaning the flatbed trailers basically follow the trajectory of the tractor unit.

[0004] The power equipment and sensor equipment of the unmanned tractor are generally located on the tractor. When the tractor pulls a fully loaded flatbed trailer to the side of the aircraft or into the manufacturing workshop, it will separate the tractor from the flatbed trailer, leaving the workers to unload the goods slowly. The tractor will then take the empty flatbed trailer back to the terminal or warehouse to pull another fully loaded flatbed trailer.

[0005] However, because the flatbed truck and the tractor are only roughly aligned on the same track with some deviation, and because the flatbed truck may not actually be aligned with the tractor when it is unloaded or the road surface is slippery and lacks traction, a collision hazard may occur. Therefore, if the unmanned tractor does not obtain the location information of the flatbed truck and only the tractor plans the route, a collision hazard is likely to occur in real-world scenarios. Furthermore, if there is a dynamic obstacle, such as a bicycle coming from a perpendicular direction, the tractor may be able to safely pass in front of the bicycle, but because there is a flatbed truck group behind the tractor, if the bicycle does not brake in time or is not paying attention, it may collide with the flatbed truck group, and the tractor may not be able to detect the impact and will continue to drive, resulting in running over or dragging the bicycle.

[0006] Furthermore, while adding sensors such as LiDAR, IMU, and RTK to the flatbed truck assembly can enable positional awareness, these sensors are expensive, and replacing the flatbed truck assembly is troublesome due to the frequent need to plug and unplug them. Each time, the installation position of the sensors needs to be ensured, which is not suitable for scenarios that require frequent replacement of the flatbed truck assembly.

[0007] If the size and quantity information of the flatbed trucks are pre-input into the autonomous driving system, the system can draw the theoretical position of the flatbed trucks in real time based on the trajectory of the tractor to avoid collisions. However, this method is only applicable to scenarios where the tractor only tows a fixed number of flatbed trucks at a time, and the position of the flatbed trucks is only a theoretically predicted position, not the actual perceived position, so there is still a large deviation. Summary of the Invention

[0008] The purpose of this application is to provide a vehicle body area detection method, a tractor and an obstacle avoidance system for the tractor, which does not require the placement of sensors on the flatbed truck, does not limit the number of flatbed trucks, and has high sensing accuracy.

[0009] To solve the above-mentioned technical problems, the embodiments of this application adopt the following technical solutions:

[0010] In a first aspect, this application provides a vehicle body area detection method applied to a tractor unit, wherein the tractor unit is detachably connected to a flatbed trailer assembly, the rear of the flatbed trailer assembly is detachably fitted with a banner, and the tractor unit is equipped with a lidar; the method includes:

[0011] The three-dimensional position information of the banner is obtained by the lidar;

[0012] The location of the flatbed truck is calculated based on the three-dimensional position information of the banner, the length of the flatbed truck, the external parameters of the lidar, and the width of the banner.

[0013] The vehicle body area is obtained by combining the vehicle body area of ​​the tractor unit with the location area of ​​the flatbed truck group.

[0014] In some embodiments, the step of calculating the area where the flatbed truck group travels based on the three-dimensional position information of the banner, the length of the flatbed truck group, the extrinsic parameters of the lidar, and the width information of the banner includes:

[0015] Based on the external parameter information of the lidar, the driving information of the tractor, and the length of the flatbed, the coordinates of the connecting axis of the tractor and the trajectory curve are determined.

[0016] The position curve of the flatbed truck group is obtained by performing fifth-order polynomial curve fitting using the connecting axis coordinates, the trajectory curve, and the three-dimensional position information of the banner.

[0017] Centered on the position curve, a strip area corresponding to the width information of the banner is set as the position area of ​​the flatbed vehicle group.

[0018] In some embodiments, the step of performing fifth-order polynomial curve fitting using the connecting axis coordinates, the trajectory curve, and the three-dimensional position information of the banner to obtain the position curve of the flatbed vehicle group includes:

[0019] Calculate the coordinates of the center point of the banner based on its three-dimensional position information;

[0020] The coordinates of the center point of the banner are transformed into the planar coordinate system of the lidar to obtain the first coordinates of the center point of the banner;

[0021] Based on the first coordinate, the connecting axis coordinate, and the trajectory curve, a fifth-order polynomial is used for curve fitting; the curve fitting formula is: l(x)=p0+p1x+p2x 2 +p3x 3 +p4x 4 +p5x 5 Where l(x) represents the position curve, x is the independent variable, and p0, p1, ..., p5 are coefficients to be determined;

[0022] When the position curve satisfies the constraint conditions, p0, p1, ..., p5 are determined to determine the position curve of the flatbed vehicle group.

[0023] In some embodiments, the constraint conditions include a first constraint condition and a second preset condition, wherein the first constraint condition is that the position curve passes through the coordinate point (x). c ,y c ) and coordinates (x) f ,y f ), where (x c ,y c (x) represents the coordinates of the connecting axes; f ,y f () represents the first coordinate;

[0024] The second constraint is that the coefficients to be determined for the position curve must satisfy the minimum cost function.

[0025] In some embodiments, after combining the vehicle body area of ​​the tractor with the location area of ​​the flatbed trailer group to obtain the vehicle body area, the method further includes:

[0026] Obstacle avoidance control or emergency braking control is performed based on the vehicle body area.

[0027] Secondly, this application also provides a tractor unit, the tractor unit comprising:

[0028] LiDAR;

[0029] At least one processor, and

[0030] A memory, communicatively connected to the processor, stores instructions executable by the at least one processor to implement the steps of the vehicle body area detection method as described in the first aspect above.

[0031] Thirdly, this application also provides a tractor obstacle avoidance system, including a flatbed trailer assembly and a tractor as described in the second aspect; the tractor is connected to the flatbed trailer assembly, and a banner is detachably installed at the rear of the flatbed trailer assembly.

[0032] In some embodiments, the banner includes a banner body, a horizontal bar, and a vertical bar, wherein the horizontal bar and the banner body are both perpendicular to the vertical bar, and the banner body is parallel to the horizontal bar.

[0033] In some embodiments, the rear of the flatbed trailer is provided with a column tube, the inner diameter of which is adapted to the outer diameter of the upright.

[0034] In some embodiments, the banner body is made of acrylic or aluminum oxide, and the banner body has a plurality of holes.

[0035] Fourthly, this application also provides a non-volatile computer-readable storage medium storing computer-executable instructions, which, when executed by a tractor, implement the steps of the vehicle body area detection method described in the first aspect above.

[0036] The beneficial effects of this application's embodiments are as follows: Unlike existing technologies, the vehicle body area detection method, tractor, and tractor obstacle avoidance system provided in this application's embodiments involve a detachable connection between the tractor and the flatbed trailer assembly. The flatbed trailer assembly includes an unlimited number of flatbed trailers, and a banner is detachably mounted at the rear of the flatbed trailer assembly. The tractor is equipped with a lidar. When the tractor needs to tow the flatbed trailer assembly, the flatbed trailer assembly is connected to the tractor, and the banner is mounted at the rear of the flatbed trailer assembly. The lidar acquires the three-dimensional position information of the banner in real time, thereby accurately calculating the area where the flatbed trailer assembly is traveling. The vehicle body area of ​​the tractor is then combined with the position area of ​​the flatbed trailer assembly to obtain the vehicle body area. Furthermore, the lidar can detect obstacles around the vehicle body area, allowing the tractor to take timely obstacle avoidance or braking actions to prevent collisions.

[0037] This application allows for easy replacement of flatbed trailers by detachably installing banners at the rear of the flatbed trailer assembly. Furthermore, the number of flatbed trailers in the assembly is unlimited, eliminating the need to install sensors on the flatbed trailers, thus saving costs and providing higher accuracy in sensing the location of the flatbed trailer assembly as it travels. Attached Figure Description

[0038] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0039] Figure 1 This is a structural schematic diagram of the obstacle avoidance system for the tractor unit in this application;

[0040] Figure 2 This is a side view of the obstacle avoidance system of the tractor unit in this application;

[0041] Figure 3 This is a schematic diagram of the structure of the flatbed trailer assembly with a banner installed at the rear;

[0042] Figure 4 This is a structural diagram of the banner in this application;

[0043] Figure 5 This is a flowchart illustrating one embodiment of the vehicle body area detection method of this application;

[0044] Figure 6 This is a schematic diagram of the travel trajectory of the tractor unit pulling the flatbed trailer in this application;

[0045] Figure 7 This is a schematic diagram of the structure of one embodiment of the vehicle body area detection device of this application;

[0046] Figure 8 This is a schematic diagram of the hardware structure of the controller in one embodiment of the tractor vehicle of this application. Detailed Implementation

[0047] The present application will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application. These all fall within the protection scope of the present application.

[0048] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0049] It should be noted that, unless there is a conflict, the various features in the embodiments of this application can be combined with each other, all of which are within the protection scope of this application. Furthermore, although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than the module division in the device or the order in the flowchart. In addition, the terms "first," "second," and "third" used herein do not limit the data or execution order, but only distinguish identical or similar items with essentially the same function and effect.

[0050] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0051] Furthermore, the technical features involved in the various embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0052] The vehicle body area detection method and device provided in this application can be applied to tractor vehicles, and the tractor vehicle in this application is one type of unmanned driving application.

[0053] This application also provides a tractor obstacle avoidance system, such as... Figure 1 As shown, Figure 1 This is a schematic diagram of the obstacle avoidance system of the tractor unit 102. The obstacle avoidance system 100 includes a flatbed trailer 101 and a tractor unit 102. The tractor unit 102 is connected to the flatbed trailer 101, and a banner 103 is detachably installed at the rear of the flatbed trailer 101.

[0054] Specifically, a lidar 1021 is installed on the top of the tractor 102, and the detection range of the lidar 1021 is the rear of the tractor 102. The rear connecting shaft 1022 of the tractor 102 can rigidly connect to the flatbed assembly 101, which includes multiple flatbeds, and the number of flatbeds is not limited. After each loading and unloading, a banner 103 is installed at the rear of the flatbed assembly 101 to be transported, such as... Figure 1 and Figure 2 As shown, Figure 1 In the middle, the tractor 102 is connected to the flatbed trailer 101, and the rear of the flatbed trailer 101 is equipped with a banner 103. Figure 2 This is a side view.

[0055] like Figure 3 As shown, Figure 3This is a schematic diagram showing the structure of a flatbed trailer 101 with a banner 103 attached to its rear. Figure 4 As shown, Figure 4 This is a structural schematic diagram of banner 103. Banner 103 includes a vertical pole 1031, a horizontal pole 1032, and a banner body 1033. Both the horizontal pole 1032 and the banner body 1033 are perpendicular to the vertical pole 1031, and the banner body 1033 is parallel to the horizontal pole 1032. One end of the vertical pole 1031 is conveniently inserted into the rear of the flatbed trailer assembly 101, and the other end of the vertical pole 1031 is fixedly connected to the horizontal pole 1032. The other end of the vertical pole 1031 is also fixedly connected to the banner body 1033.

[0056] Furthermore, the length of the crossbar 1032 corresponds to the length of the banner body 1033 and the width of the rear of the flatbed trailer 101.

[0057] The horizontal bar 1032 facilitates the reinforcement of the vertical pole 1031 and reduces the stress on the banner body 1033. At the same time, the horizontal bar 1032 also serves as a force application point for easy lifting with one hand.

[0058] In some embodiments, the rear of the flatbed trailer 101 is provided with a column tube (not shown), the inner diameter of which is adapted to the outer diameter of the upright 1031. For example, if there are two uprights 1031, then there are also two column tubes, distributed at both ends of the rear of the flatbed trailer 101. In order to install one end of the upright 1031 at the rear of the flatbed trailer 101, the inner diameter of the column tube is adapted to the outer diameter of the upright 1031, so that the upright 1031 can be inserted into the column tube, thereby fixing the banner 103 to the rear of the flatbed trailer 101 as a whole.

[0059] After the banner 103 is installed at the rear of the flatbed truck assembly 101, the bottom of the banner body 1033 is higher than the cargo height of the flatbed truck. The vertical width (short side width) of the banner body 1033 is generally not less than 50 cm, so that when the 16-line lidar is about 14 meters away from the banner, it can be ensured that the two lidar beams can detect the banner 103. Correspondingly, if a lidar with a high beam or a higher vertical beam density is used, or if the total length of the flatbed truck assembly 101 is short, the vertical width of the banner 103 can be reduced.

[0060] In some embodiments, the banner body 1033 is provided with a plurality of holes 1034 to reduce wind resistance. Furthermore, the distribution of the plurality of holes 1034 is not limited, and the diameter of the holes 1034 does not exceed 2 centimeters.

[0061] In some embodiments, the horizontal bar 1032 and the vertical bar 1031 can be made of lightweight metals, such as stainless steel or hollow aluminum; the banner body 1033 can be made of acrylic or aluminum oxide. The entire banner 103 is lightweight and can be lifted with one hand.

[0062] By inserting the banner 103 at the rear of the flatbed truck assembly 101 and combining it with the lidar 1021, the three-dimensional position information of the banner 103 located at the rear of the flatbed truck assembly 101 can be accurately identified. Furthermore, the banner 103 can be directly inserted after each unloading, which is convenient to operate, reusable, does not require the installation of sensors on the flatbed truck, has low cost, and is not limited by the number of flatbed trucks.

[0063] Please see Figure 5 , Figure 5 This is a flowchart illustrating an embodiment of the vehicle body area detection method applied in this application. The method can be executed by a controller in the tractor 102, and includes steps S501-S503.

[0064] S501: Obtain the three-dimensional position information of the banner using the lidar.

[0065] Before the tractor pulls the flatbed trailer, a banner is installed at the rear of the flatbed trailer, such as... Figure 2 As shown, the three-dimensional position information of the banner is then detected in real time using lidar.

[0066] The banner's three-dimensional position information is calculated in real time using lidar, thereby accurately locating the rear of the flatbed truck.

[0067] S502: Calculate the area where the flatbed truck group travels based on the three-dimensional position information of the banner, the length of the flatbed truck group, the external parameter information of the lidar, and the width information of the banner.

[0068] After obtaining the three-dimensional position information of the banner through step S502, the area where the flatbed truck group travels is calculated.

[0069] In some implementations, step S502 may include:

[0070] Based on the external parameter information of the lidar, the driving information of the tractor, and the length of the flatbed, the coordinates of the connecting axis of the tractor and the trajectory curve are determined.

[0071] The position curve of the flatbed truck group is obtained by performing fifth-order polynomial curve fitting using the connecting axis coordinates, the trajectory curve, the width information of the banner, and the three-dimensional position information of the banner.

[0072] Centered on the position curve, a strip area corresponding to the width of the long side of the banner is set as the position area of ​​the flatbed vehicle group.

[0073] like Figure 6 As shown, Figure 6This is a schematic diagram of the trajectory of a tractor-trailer assembly. Based on the external parameters of the lidar, the driving information of the tractor, and the length of the flatbed assembly, the coordinates of the connecting axis of the tractor and its trajectory curve are determined. Therefore, in the planar coordinate system of the lidar's top-view angle, the coordinates of the connecting axis at the rear of the tractor are determined as (x...). c ,y c The trajectory curve of the tractor is L(x), and the coordinates of the point where the trajectory curve L(x) intersects the horizontal bar are (x...). r ,y r Then, use the connecting axis coordinates (x) c ,y c The position curve l(x) of the flatbed truck group is obtained by performing a fifth-order polynomial curve fitting on the trajectory curve L(x), the width information of the banner, and the three-dimensional position information of the banner.

[0074] In some embodiments, the step of obtaining the position curve of the flatbed truck group by performing fifth-order polynomial curve fitting using the connecting axis coordinates, the trajectory curve, the width information of the banner, and the three-dimensional position information of the banner may include:

[0075] Calculate the coordinates of the center point of the banner based on its three-dimensional position information;

[0076] The coordinates of the center point of the banner are transformed into the planar coordinate system of the lidar to obtain the first coordinates of the center point of the banner;

[0077] Based on the first coordinate, the connecting axis coordinate, and the trajectory curve, a fifth-order polynomial is used for curve fitting; the curve fitting formula is: l(x)=p0+p1x+p2x 2 +p3x 3 +p4x 4 +p5x 5 Where l(x) represents the position curve, x is the independent variable, and p0, p1, ..., p5 are coefficients to be determined;

[0078] When the position curve satisfies the constraint conditions, p0, p1, ..., p5 are determined to determine the position curve of the flatbed vehicle group.

[0079] Specifically, firstly, based on the three-dimensional position information of the banner, the coordinates of the center point of the banner are calculated; then, the coordinates of the center point of the banner are transformed into the planar coordinate system of the lidar to obtain the first coordinate (x, y) of the center point of the banner. f ,y f The position curve of the flatbed car group is represented by l(x), and when fitting a fifth-order polynomial curve, it is represented by Equation 1:

[0080] l(x) = p0 + p1x + p2x 2 +p3x 3 +p4x 4 +p5x 5 Formula 1;

[0081] Where p0, p1, ..., p5 are coefficients to be determined, and x is the independent variable.

[0082] To find p0, p1, ..., p5, the curve needs to satisfy the constraints. The first constraint is that the position curve l(x) passes through the coordinate point (x...). c ,y c ) and coordinates (x) f ,y f ), that is, y C =l(x C ), y f =l(x f ), x c and x f Substituting into Formula 1, multiple p0, p1, ..., p5 can be obtained. To further determine p0, p1, ..., p5, a second constraint is required. The second constraint is that the coefficients to be determined of the position curve l(x) must satisfy the minimum cost function. Specifically, the OSQP solver is used to minimize the cost function of the position curve l(x). If Formula 2 is satisfied, then p0, p1, ..., p5 can be determined.

[0083] cost = |l(x) - L(x)| + |l'(x) - L'(x)| (Formula 2)

[0084] When Equation 2 is satisfied, the second constraint condition is also satisfied, and p0, p1, ..., p5 are determined. Thus, the position curve l(x) can be determined.

[0085] Next, with the position curve l(x) as the center, a strip area corresponding to the width information of the banner is set as the position area of ​​the flatbed vehicle group, and the width information is w.

[0086] S503: Combine the body area of ​​the tractor with the location area of ​​the flatbed truck group to obtain the body area.

[0087] Since the tractor unit has a fixed range in the coordinate system of the lidar during autonomous driving, and the range of the tractor unit itself has been determined in the autonomous driving program, the range of the tractor unit can be directly combined with the location area of ​​the flatbed truck group to obtain the vehicle body area.

[0088] In some embodiments, after combining the vehicle body area of ​​the tractor with the location area of ​​the flatbed trailer to obtain the vehicle body area, the method further includes:

[0089] Obstacle avoidance control or emergency braking control is performed based on the vehicle body area.

[0090] Specifically, the lidar can also emit laser lines to the surrounding environment, enabling the tractor to sense surrounding obstacles. Furthermore, the tractor's controller determines the positional relationship between the obstacle and the vehicle's area, that is, whether the obstacle is too close to the vehicle's area or has intruded into the vehicle's area. If the obstacle is too close to the vehicle's area or has intruded into the vehicle's area, the autonomous driving algorithm can perform obstacle avoidance control or emergency braking control to avoid colliding with the obstacle.

[0091] In embodiments of this application, the tractor and the flatbed assembly are detachably connected. The flatbed assembly includes an unlimited number of flatbeds, and a banner is detachably mounted at the rear of the flatbed assembly. The tractor is equipped with a lidar. When the tractor needs to tow the flatbed assembly, the flatbed assembly is connected to the tractor, and the banner is mounted at the rear of the flatbed assembly. The lidar acquires the three-dimensional position information of the banner in real time, thereby accurately calculating the area where the flatbed assembly is traveling. The vehicle body area of ​​the tractor is then combined with the position area of ​​the flatbed assembly to obtain the vehicle body area. The lidar can also detect obstacles around the vehicle body area, allowing the tractor to take timely obstacle avoidance or braking actions to prevent collisions.

[0092] This application allows for easy replacement of flatbed trailers by detachably installing banners at the rear of the flatbed trailer assembly. Furthermore, the number of flatbed trailers in the assembly is unlimited, eliminating the need to install sensors on the flatbed trailers, thus saving costs and providing higher accuracy in sensing the location of the flatbed trailer assembly as it travels.

[0093] This application also provides a vehicle body area detection device for use in a tractor. Please refer to [link / reference]. Figure 7 This illustration shows the structure of a vehicle body area detection device 700 provided in an embodiment of this application. The vehicle body area detection device 700 includes:

[0094] The acquisition module 701 is used to acquire the three-dimensional position information of the banner through the lidar;

[0095] The calculation module 702 is used to calculate the area where the flatbed truck group travels based on the three-dimensional position information of the banner, the length of the flatbed truck group, the external parameter information of the lidar, and the width information of the banner.

[0096] The combination module 703 is used to combine the body area of ​​the tractor with the position area of ​​the flatbed truck group to obtain the body area.

[0097] In embodiments of this application, the tractor and the flatbed assembly are detachably connected. The flatbed assembly includes an unlimited number of flatbeds, and a banner is detachably mounted at the rear of the flatbed assembly. The tractor is equipped with a lidar. When the tractor needs to tow the flatbed assembly, the flatbed assembly is connected to the tractor, and the banner is mounted at the rear of the flatbed assembly. The lidar acquires the three-dimensional position information of the banner in real time, thereby accurately calculating the area where the flatbed assembly is traveling. The vehicle body area of ​​the tractor is then combined with the position area of ​​the flatbed assembly to obtain the vehicle body area. The lidar can also detect obstacles around the vehicle body area, allowing the tractor to take timely obstacle avoidance or braking actions to prevent collisions.

[0098] This application allows for easy replacement of flatbed trailers by detachably installing banners at the rear of the flatbed trailer assembly. Furthermore, the number of flatbed trailers in the assembly is unlimited, eliminating the need to install sensors on the flatbed trailers, thus saving costs and providing higher accuracy in sensing the location of the flatbed trailer assembly as it travels.

[0099] In some embodiments, the computing module 702 is further configured to:

[0100] Based on the external parameter information of the lidar, the driving information of the tractor, and the length of the flatbed, the coordinates of the connecting axis of the tractor and the trajectory curve are determined.

[0101] The position curve of the flatbed truck group is obtained by performing fifth-order polynomial curve fitting using the connecting axis coordinates, the trajectory curve, and the three-dimensional position information of the banner.

[0102] Centered on the position curve, a strip area corresponding to the width information of the banner is set as the position area of ​​the flatbed vehicle group.

[0103] In some embodiments, the computing module 702 is further configured to:

[0104] Calculate the coordinates of the center point of the banner based on its three-dimensional position information;

[0105] The coordinates of the center point of the banner are transformed into the planar coordinate system of the lidar to obtain the first coordinates of the center point of the banner;

[0106] Based on the first coordinate, the connecting axis coordinate, and the trajectory curve, a fifth-order polynomial is used for curve fitting; the curve fitting formula is: l(x)=p0+p1x+p2x 2 +p3x 3 +p4x 4 +p5x 5 Where l(x) represents the position curve, x is the independent variable, and p0, p1, ..., p5 are coefficients to be determined;

[0107] When the position curve satisfies the constraint conditions, p0, p1, ..., p5 are determined to determine the position curve of the flatbed vehicle group.

[0108] In some embodiments, the constraint conditions include a first constraint condition and a second constraint condition, wherein the first constraint condition is that the position curve passes through the coordinate point (x). c ,y c ) and coordinates (x) f ,y f ), where (x c ,y c (x) represents the coordinates of the connecting axes; f ,y f () represents the first coordinate;

[0109] The second constraint is that the coefficients to be determined for the position curve must satisfy the minimum cost function.

[0110] In some embodiments, the device 700 further includes a control module 704, configured to:

[0111] Obstacle avoidance control or emergency braking control is performed based on the vehicle body area.

[0112] It should be noted that the above-described apparatus can execute the method provided in the embodiments of this application, and has the corresponding functional modules and beneficial effects for executing the method. Technical details not described in detail in the apparatus embodiments can be found in the method provided in the embodiments of this application.

[0113] Figure 8 This is a schematic diagram of the hardware structure of the controller of the tractor 102 in one embodiment of the tractor vehicle, as shown below. Figure 8 As shown, the controller includes:

[0114] One or more processors 111 and memory 112. Figure 8 The example uses a processor 111 and a memory 112.

[0115] Processor 111 and memory 112 can be connected via a bus or other means. Figure 8 Taking the example of a connection between China and Israel via a bus.

[0116] Memory 112, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as the program instructions / modules corresponding to the vehicle body area detection method in the embodiments of this application (e.g., attached...). Figure 7The acquisition module 701, calculation module 702, combination module 703, and control module 704 are shown. The processor 111 executes various functional applications and data processing of the controller by running non-volatile software programs, instructions, and modules stored in the memory 112, thereby implementing the vehicle body area detection method of the above method embodiment.

[0117] The memory 112 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the personnel access detection device. Furthermore, the memory 112 may include high-speed random access memory and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 112 may optionally include memory remotely located relative to the processor 111, and these remote memories may be connected to the tractor via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0118] The one or more modules are stored in the memory 112. When executed by the one or more processors 111, they perform the vehicle body region detection method in any of the above method embodiments, for example, the method described above. Figure 5 Method steps S501 to S503; implementation Figure 7 The functions of modules 701-704 in the document.

[0119] The above-described product can perform the methods provided in the embodiments of this application, and has the corresponding functional modules and beneficial effects for performing the methods. Technical details not described in detail in this embodiment can be found in the methods provided in the embodiments of this application.

[0120] This application provides a non-volatile computer-readable storage medium storing computer-executable instructions that are executed by one or more processors, for example... Figure 8 One of the processors 111 can enable the one or more processors to execute the vehicle body region detection method in any of the above method embodiments, for example, to perform the above-described... Figure 5 Method steps S501 to S503; implementation Figure 7 The functions of modules 701-704 in the document.

[0121] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0122] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented using software and a general-purpose hardware platform, or of course, using hardware. Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A vehicle body area detection method, applied to a tractor, wherein the tractor is detachably connected to a flatbed assembly, the rear of the flatbed assembly is detachably fitted with a horizontal bar, and the tractor is equipped with a lidar; characterized in that, The method includes: The three-dimensional position information of the banner is obtained by the lidar; Based on the external parameter information of the lidar, the driving information of the tractor, and the length of the flatbed, the coordinates of the connecting axis of the tractor and the trajectory curve are determined. The position curve of the flatbed truck group is obtained by performing fifth-order polynomial curve fitting using the connecting axis coordinates, the trajectory curve, and the three-dimensional position information of the banner. Centered on the position curve, a strip area corresponding to the width information of the banner is set as the position area of ​​the flatbed vehicle group; The vehicle body area is obtained by combining the vehicle body area of ​​the tractor unit with the location area of ​​the flatbed truck group.

2. The method according to claim 1, characterized in that, The step of performing fifth-order polynomial curve fitting using the connecting axis coordinates, the trajectory curve, and the three-dimensional position information of the banner to obtain the position curve of the flatbed vehicle group includes: Calculate the coordinates of the center point of the banner based on its three-dimensional position information; The coordinates of the center point of the banner are transformed into the planar coordinate system of the lidar to obtain the first coordinates of the center point of the banner; Based on the first coordinate, the connecting axis coordinate, and the trajectory curve, a fifth-order polynomial is used for curve fitting; the curve fitting formula is: ,in, Indicates the position curve, As the independent variable, , , ..., All are coefficients to be determined; When the position curve satisfies the constraint conditions, determine , , ..., To determine the position curve of the flatbed truck group.

3. The method according to claim 2, characterized in that, The constraints include a first constraint and a second constraint, wherein the first constraint is that the position curve passes through the coordinate point. and coordinate points ,in, Indicates the coordinates of the connecting axes; Indicates the first coordinate; The second constraint is that the coefficients to be determined for the position curve must satisfy the minimum cost function.

4. The method according to any one of claims 1 to 3, characterized in that, After combining the vehicle body area of ​​the tractor unit with the location area of ​​the flatbed trailer group to obtain the vehicle body area, the method further includes: Obstacle avoidance control or emergency braking control is performed based on the vehicle body area.

5. A tractor unit, characterized in that, The tractor unit includes: LiDAR; At least one processor, and A memory communicatively connected to the processor, the memory storing instructions executable by the at least one processor to perform the steps of the method as described in any one of claims 1 to 4.

6. A tractor obstacle avoidance system, characterized in that, It includes a flatbed trailer assembly and a tractor as described in claim 5; the tractor is connected to the flatbed trailer assembly, and a banner is detachably mounted on the rear of the flatbed trailer assembly.

7. The system according to claim 6, characterized in that, The banner includes a banner body, a horizontal bar, and a vertical bar. The horizontal bar and the banner body are both perpendicular to the vertical bar, and the banner body is parallel to the horizontal bar.

8. The system according to claim 7, characterized in that, The rear of the flatbed trailer is equipped with a column tube, the inner diameter of which is adapted to the outer diameter of the upright.

9. The system according to claim 7, characterized in that, The banner body is made of acrylic or aluminum oxide, and has several holes.

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