Multi-axle transport vehicle steering control method and system suitable for narrow spaces

Abstract

The present application belongs to the field of transport vehicle steering control, in order to solve the problem that the current multi-formation wheeled vehicle in-place steering mode is difficult to be applied to the in-place steering scene of multi-formation wheeled vehicle transporting long rod-shaped parts under the working condition of narrow space, the present application provides a multi-linkage transport vehicle steering control method and system suitable for narrow space. The multi-linkage transport vehicle steering control method suitable for narrow space includes that in the steering process, the coordinates of the centers of the vehicles of the multi-linkage transport vehicle and the longitudinal speeds of the vehicles are acquired in real time, the centers of the vehicles of the linkage transport vehicle are always kept collinear and the longitudinal speeds of all the vehicles are kept consistent; the vehicle corresponding to the in-place steering center of the multi-linkage transport vehicle is determined as the main vehicle, and the other vehicles are auxiliary vehicles, and all the auxiliary vehicles are controlled to perform corresponding circumferential steering motion with the main vehicle as the center. It is suitable for the working condition of narrow space and improves the transportation efficiency.

Description

Technical Field

[0001] This invention belongs to the field of steering control for transport vehicles, and particularly relates to a steering control method and system for multi-linkage transport vehicles suitable for confined spaces. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] When transporting long pole-shaped components (usually greater than 15m) in confined spaces using multi-unit wheeled vehicles, it is usually necessary to turn the multi-unit wheeled vehicles around a certain point of the long pole component in order to avoid obstacles.

[0004] Existing on-the-spot steering methods for multi-unit wheeled vehicles include articulated chain steering, modular power steering, and drawbar steering. Articulated chain steering offers high maneuverability, with a turning radius significantly smaller than a single vehicle of equivalent length. Drawbar steering utilizes a drawbar for forced steering; however, long rod-like components are typically longer than a single wheeled vehicle. When transporting these components, they are usually fixed at the center point of each vehicle section. When at least two vehicles are turning along a curve, neither articulated chain steering nor drawbar steering can guarantee that the center points of each vehicle are aligned in a straight line, potentially leading to the breakage of the rigid long rod-like component. Modular power steering is typically used for extremely heavy loads and employs distributed hydraulic drive. However, for on-the-spot steering of long rod-like components in confined spaces, it is bulky and has a complex control system.

[0005] In summary, the current on-the-spot turning method for multi-unit wheeled vehicles is not suitable for on-the-spot turning scenarios where multi-unit wheeled vehicles are transporting long rod-shaped components in confined spaces. Summary of the Invention

[0006] To address the technical problems mentioned above, this invention provides a steering control method and system for multi-unit transport vehicles in confined spaces. This method is suitable for in-situ steering scenarios involving multi-unit wheeled vehicles transporting long rod-shaped components in confined spaces, thereby improving transportation efficiency.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: The first aspect of the present invention provides a steering control method for multi-linkage transport vehicles suitable for confined spaces.

[0008] A steering control method for multi-link transport vehicles suitable for confined spaces, comprising: During the turning process, the center coordinates of each vehicle of the multi-linked transport vehicle and the longitudinal speed of each vehicle are obtained in real time, and the centers of each vehicle of the multi-linked transport vehicle are kept collinear and the longitudinal speed of all vehicles is kept consistent. The vehicle corresponding to the stationary turning center of the multi-linked transport vehicle is designated as the main vehicle, and the other vehicles are designated as auxiliary vehicles. All auxiliary vehicles are controlled to perform corresponding circular turning movements around the main vehicle. When the stationary turning center of the multi-linked transport vehicle is the head vehicle / tail vehicle, the head vehicle / tail vehicle is the master vehicle and the other vehicles are auxiliary vehicles. All auxiliary vehicles are controlled to make circular turning movements in the same direction around the master vehicle at the same time. When the stationary turning center of the multi-linked transport vehicle is the middle vehicle, the middle vehicle is the master vehicle and the other vehicles are auxiliary vehicles. All auxiliary vehicles are controlled to make circular turning movements in the opposite direction around the master vehicle.

[0009] In one implementation method, during the circular turning motion, the rotational angular velocity of the vehicle center of each auxiliary vehicle and the rotational angular velocity of each wheel center of each auxiliary vehicle around the main vehicle are equal.

[0010] The advantage of the above technical solution is that it can ensure that the distance between each auxiliary vehicle remains consistent, and realize the coordinated movement of multiple linked transport vehicles.

[0011] As one implementation method, when the intermediate vehicle is the main vehicle, the main vehicle is controlled to stop in place and all auxiliary vehicles are rotated and turned in place until the direction of vehicle movement is perpendicular to the transport component. The steering angle of all auxiliary vehicles is adjusted, and the vehicle center of the main vehicle is used as the steering center to perform circular turning motion. Control all auxiliary vehicles to perform circular turning motions to the set position, and the main vehicle to rotate and turn in place to the corresponding position and then stop rotating in place; then control all auxiliary vehicles to perform rotating and turning motions in place until the forward direction of all auxiliary vehicles is parallel to the transport component. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

[0012] The advantages of the above technical solution are that, when the intermediate vehicle is the main vehicle, the above three-stage steering control is adopted. In the first stage, the main vehicle is stationary, and all auxiliary vehicles perform circular turning motion with the vehicle center of the main vehicle as the turning center. The second stage is the forward direction control of the auxiliary vehicles and the main vehicle. The third stage is the control of the wheel steering angle of the auxiliary vehicles. Based on the circular turning motion with the vehicle center of the main vehicle as the turning center and the stationary rotation motion of each vehicle, the coordinated movement of multiple linked transport vehicles is finally realized.

[0013] As one implementation method, when the lead car / tail car is the main car, the main car is controlled to stop in place and all auxiliary cars are rotated and turned in place until the direction of vehicle movement is perpendicular to the transport component. Adjust the wheel steering of all auxiliary vehicles, control all auxiliary vehicles to make circular turning motions around the vehicle center of the main vehicle to the corresponding set position and then stop circular turning, while controlling the main vehicle to make stationary rotational turning motions. Then control all auxiliary vehicles to perform stationary rotation and steering movements, while controlling the main vehicle to continue stationary rotation and steering movements until the forward direction of all vehicles is parallel to the transport component, and then stop the stationary rotation and steering movements of the main vehicle and all auxiliary vehicles. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

[0014] The advantages of the above technical solution are that, when the lead vehicle / tail vehicle is the main vehicle, the above four-stage steering control is adopted. The first stage is that the main vehicle is stationary and the forward direction of all auxiliary vehicles is controlled. The second stage is that the main vehicle is stationary and the main vehicle performs circular turning motion with the vehicle center of the main vehicle as the turning center. The third stage is the forward direction control of the auxiliary vehicles and the main vehicle. The fourth stage is the control of the wheel steering angle of the auxiliary vehicles. Based on the circular turning motion with the vehicle center of the main vehicle as the turning center and the stationary rotation motion of each vehicle, the coordinated movement of multiple linked transport vehicles is finally realized.

[0015] In one implementation method, during the stationary rotational steering motion, the steering angles of all wheels of the vehicle are equal.

[0016] The advantage of the above technical solution is that it can ensure the stability of the rotation and turning motion in place.

[0017] In one implementation, the vehicle corresponding to the in-situ turning center of the multi-linked transport vehicle is determined by the obstacle information in the confined space and the positions of each vehicle in the multi-linked transport vehicle.

[0018] The advantage of the above technical solution is that it can improve the movement efficiency of multi-link transport vehicles.

[0019] A second aspect of the present invention provides a steering control system for multi-linkage transport vehicles suitable for confined spaces.

[0020] In one or more embodiments, a steering control system for a multi-linkage transport vehicle suitable for confined spaces includes: The vehicle speed control module is used to obtain the center coordinates of each vehicle of the multi-linked transport vehicle and the longitudinal speed of each vehicle in real time during the turning process, and to control the center of each vehicle of the multi-linked transport vehicle to always keep collinear and the longitudinal speed of all vehicles to be consistent. The steering motion module is used to determine the vehicle corresponding to the stationary turning center of the multi-linked transport vehicle as the main vehicle, and the other vehicles as auxiliary vehicles, and control all auxiliary vehicles to perform corresponding circular turning motions with the main vehicle as the center. In the steering motion module, when the in-situ steering center of the multi-linked transport vehicle is the lead vehicle / tail vehicle, the lead vehicle / tail vehicle is the master vehicle and the other vehicles are auxiliary vehicles, and all auxiliary vehicles are controlled to perform circular steering motion in the same direction around the master vehicle simultaneously; when the in-situ steering center of the multi-linked transport vehicle is the middle vehicle, the middle vehicle is the master vehicle and the other vehicles are auxiliary vehicles, and all auxiliary vehicles are controlled to perform circular steering motion in the opposite direction around the master vehicle.

[0021] In one implementation, during the circular steering motion of the steering module, the rotational angular velocity of the vehicle center of each auxiliary vehicle and the rotational angular velocity of each wheel center of each auxiliary vehicle around the main vehicle are equal.

[0022] In one implementation, in the steering motion module, when the intermediate vehicle is the main vehicle, the main vehicle is controlled to stop in place and all auxiliary vehicles are rotated and turned in place until the vehicle's forward direction is perpendicular to the transport component. The steering angle of all auxiliary vehicles is adjusted, and the vehicle center of the main vehicle is used as the steering center to perform circular steering motion. Control all auxiliary vehicles to perform circular turning motions to the set position, and the main vehicle to rotate and turn in place to the corresponding position and then stop rotating in place; then control all auxiliary vehicles to perform rotating and turning motions in place until the forward direction of all auxiliary vehicles is parallel to the transport component. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

[0023] In one implementation, in the steering motion module, when the lead car / tail car is the main car, the main car is controlled to stop in place and all auxiliary cars are each rotated in place to turn so that the direction of vehicle movement is perpendicular to the transport component. Adjust the wheel steering of all auxiliary vehicles, control all auxiliary vehicles to make circular turning motions around the vehicle center of the main vehicle to the corresponding set position and then stop circular turning, while controlling the main vehicle to make stationary rotational turning motions. Then control all auxiliary vehicles to perform stationary rotation and steering movements, while controlling the main vehicle to continue stationary rotation and steering movements until the forward direction of all vehicles is parallel to the transport component, and then stop the stationary rotation and steering movements of the main vehicle and all auxiliary vehicles. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

[0024] In one implementation, during the stationary rotational steering motion in the steering module, the steering angles of all wheels of the vehicle are equal.

[0025] In one or more embodiments, a multi-linkage transport vehicle steering control system suitable for confined spaces is provided, which includes a main controller and individual vehicle controllers that are respectively communicatively connected to the main controller. The single-vehicle controller is configured to control the corresponding vehicle in the multi-linked transport vehicle to perform in-situ rotational turning motion and circular turning motion; the main controller is configured to execute the steps in the multi-linked transport vehicle steering control method applicable to confined spaces as described above. Each vehicle in the multi-linkage transport vehicle has a sliding cavity on its upper surface. A load-bearing structure is installed in the sliding cavity. The load-bearing structure includes a sliding load-bearing device and a rotating load-bearing device. The sliding load-bearing device is locked in the sliding cavity, and the rotating load-bearing device is rotatably connected to the sliding load-bearing device.

[0026] A third aspect of the present invention provides a computer-readable storage medium.

[0027] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described method for steering control of multi-linked transport vehicles in confined spaces.

[0028] A fourth aspect of the present invention provides a computer device.

[0029] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the above-described method for steering control of multi-linked transport vehicles in confined spaces.

[0030] Compared with the prior art, the beneficial effects of the present invention are: During the turning process, this invention controls the centers of all vehicles in the multi-linked transport vehicle to remain collinear and maintain a consistent longitudinal speed. The vehicle corresponding to the stationary turning center of the multi-linked transport vehicle is designated as the main vehicle, and the other vehicles are designated as auxiliary vehicles. All auxiliary vehicles are controlled to perform corresponding circular turning movements around the main vehicle. There are no mechanical connection constraints between the vehicles, enabling straight, oblique, and stationary turning movements in single-vehicle mode. This achieves decoupling of the wheel system from the rigid chassis. Through the coordinated control of the main vehicle and auxiliary vehicles, the center points of n (n greater than or equal to 3) vehicles are made collinear and maintain a fixed distance during the turning process, ultimately realizing the turning control of the multi-linked transport vehicle.

[0031] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0032] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0033] Figure 1 This is a schematic diagram of a multi-linkage transport vehicle steering control method applicable to confined spaces according to an embodiment of the present invention; Figure 2 This is a schematic diagram of a single AGV transport vehicle turning in a circular direction according to an embodiment of the present invention; Figure 3 This is a schematic diagram of a single AGV transport vehicle rotating and turning in place according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the coordinated steering of three AGV transport vehicles according to an embodiment of the present invention; Figure 5 This is the steering control process of a multi-linkage transport vehicle when the lead car / tail car is the main vehicle in an embodiment of the present invention; Figure 6 These are schematic diagrams of state 1 and state 2 with the head car / tail car as the main vehicle in an embodiment of the present invention; Figure 7 These are schematic diagrams of states 3 and 4 of an embodiment of the present invention, with the lead car / tail car as the main vehicle; Figure 8 This is a schematic diagram of the speed and position of state 4 with the head car / tail car as the main car in an embodiment of the present invention; Figure 9 These are schematic diagrams of states 5 and 6 of an embodiment of the present invention, with the lead car / tail car as the main vehicle. Figure 10 These are schematic diagrams of states 7 and 8 of an embodiment of the present invention, with the lead car / tail car as the main vehicle. Figure 11 This is the steering control process of a multi-linkage transport vehicle when the intermediate vehicle is the main vehicle, according to an embodiment of the present invention; Figure 12 These are schematic diagrams of state 1 and state 2 when the intermediate vehicle is the main vehicle in an embodiment of the present invention; Figure 13 These are schematic diagrams of states 3 and 4 when the intermediate vehicle is the main vehicle in an embodiment of the present invention; Figure 14 This is a schematic diagram of the speed and position of state 3 with the intermediate vehicle as the main vehicle in an embodiment of the present invention; Figure 15 These are schematic diagrams of states 5 and 6 when the intermediate vehicle is the main vehicle in an embodiment of the present invention; Figure 16 This is a schematic diagram of the steering control system structure of a multi-linkage transport vehicle suitable for confined spaces according to an embodiment of the present invention; Figure 17 This is an AA view of the load-bearing structure according to an embodiment of the present invention; Figure 18 These are the front view and BB / CC view of the load-bearing structure according to an embodiment of the present invention. Detailed Implementation

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0036] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0037] Terminology Explanation: Multi-unit wheeled vehicles consist of multiple car bodies or modules connected by articulation points or connectors, and are used in scenarios such as heavy transportation (wind turbine blades, transformers) and special operations (rockets, vehicle wiring ducts or other long components).

[0038] Articulated chain steering: Multi-unit wheeled vehicles consist of multiple car bodies (such as 2 or more) connected in series by vertical articulation pins; each articulation point is equipped with a hydraulic cylinder, which pushes the adjacent car bodies to rotate relative to each other around the articulation pin, thereby achieving overall steering.

[0039] Modular power steering: In ultra-long or ultra-heavy transportation (such as wind turbine blades and transformers), the vehicle is composed of multiple self-propelled and steering modular units (SPMT, Self-Propelled Modular Transporter). The wheelset of each module can be controlled independently. The vehicle can be considered as having a rigid chassis with multiple independent self-propelled and steering modular units set under the rigid chassis. To achieve on-the-spot steering, the differential steering of all wheelsets is controlled (the differential steering center point of all wheelsets is the same fixed point) to ensure the vehicle can turn on the spot.

[0040] Forced steering with drawbar: The steering system of highway freight trailers and airport baggage tractor units (tractor unit + multiple trailers) adopts forced steering with drawbar. The trailer's steering wheels are hinged to the drawbar via the steering follower boom, and the lateral movement of the drawbar forces the trailer wheels to turn.

[0041] In one or more embodiments, such as Figure 1 As shown, a steering control method for multi-linkage transport vehicles suitable for confined spaces is provided, which includes: Step 1: During the turning process, the center coordinates of each vehicle of the multi-linked transport vehicle and the longitudinal speed of each vehicle are obtained in real time, and the centers of each vehicle of the multi-linked transport vehicle are kept collinear and the longitudinal speed of all vehicles is kept consistent. Step 2: Determine the vehicle corresponding to the in-situ turning center of the multi-link transport vehicle as the main vehicle, and the other vehicles as auxiliary vehicles. Control all auxiliary vehicles to perform corresponding circular turning movements around the main vehicle. Specifically, when the in-situ turning center of the multi-link transport vehicle is the head vehicle / tail vehicle, the head vehicle / tail vehicle is the main vehicle, and the other vehicles are auxiliary vehicles. Control all auxiliary vehicles to simultaneously perform circular turning movements in the same direction around the main vehicle. When the in-situ turning center of the multi-link transport vehicle is the middle vehicle, the middle vehicle is the main vehicle, and the other vehicles are auxiliary vehicles. Control all auxiliary vehicles to perform circular turning movements in the opposite direction around the main vehicle.

[0042] During the circular turning motion, the rotational angular velocity of the vehicle center of each auxiliary vehicle and the rotational angular velocity of each wheel center of each auxiliary vehicle around the main vehicle are all equal. This ensures that the distance between each auxiliary vehicle remains consistent, enabling the coordinated movement of multiple linked transport vehicles.

[0043] The vehicles are defined as follows, starting from the rear of the group, as vehicles 1, 2, 3, ..., n (n≥3). The following explanation uses an AGV (Automated Guided Vehicle) as an example to illustrate the specific principles of the circular turning motion and stationary rotation motion in this embodiment of the invention. Figure 2 As shown, controlling the four wheel angles and rotation speeds of a single AGV transport vehicle causes the vehicle to rotate around the steering center. To achieve steady-state rotation, i.e., the vehicle center and the center of the four wheels All around the center of rotation Rotational motion. Figure 2 The parameters are explained below: Indicates the vehicle's steering center; Indicates the center of the vehicle; Indicates the distance between the vehicle's center and the steering center; Indicates the radius of rotation of the wheel; Indicates the wheelbase between the left and right front axle wheels; Indicates the wheel spacing between the left and right rear axle wheels; This indicates the distance from the front axle to the center of the vehicle. This indicates the distance between the rear axle and the vehicle's center. Indicates the longitudinal direction of the vehicle coordinate system; Indicates the lateral direction of the vehicle coordinate system; Indicates the longitudinal speed of the vehicle; Indicates the center point of the vehicle; Indicates the wheel steering angle; Indicates the left front wheel; Indicates the right front wheel; Indicates the left rear wheel; Indicates the right rear wheel; This indicates the radius distance between the center of the wheel and the center of the vehicle's steering.

[0044] like Figure 2 As shown, the kinematic constraints for the four wheels are as follows: Front left wheel: (1) Left rear wheel: (2) Right front wheel: (3) Right rear wheel: (4) when , , , , , When the values ​​are fixed, the steering angles of the four wheels can be calculated using equations (5) to (8): Left front wheel steering angle: (5) Right front wheel steering angle: (6) Left rear wheel steering angle: (7) Right rear wheel steering angle: (8) The vehicle revolves around the center of steering. Perform steady-state circular steering, i.e., vehicle center and the center of the four wheels All around the center of rotation Perform a circular steering motion, that is, the center of the vehicle and the centers of the four wheels revolve around the steering center. Since their rotational angular velocities are equal, we get (9) when , , , , , To determine the numerical values, the center velocities of the four wheels can be obtained using equation (9), since the wheel radii are all equal. The rotational speed of the wheel can then be calculated. .

[0045] = (10) In this stationary turning and steering motion, the steering angles of all wheels of the vehicle are equal. This ensures the stability of the stationary turning and steering motion. Figure 3 As shown, the simplified in-place rotation and turning motion is made as follows: ,and (11) It can be seen that when The vehicle can turn on the spot.

[0046] like Figure 4 As shown, in this embodiment of the invention, the transport vehicle is an AGV (Automated Guided Vehicle). Those skilled in the art can select the appropriate vehicle based on actual conditions. For a group consisting of three or more AGVs, four colors—blue, pink, black, and red—are used to represent different states during the turning process. Simultaneously, the vehicles are defined as follows: starting from the rear of the group, vehicles 1, 2, 3…n (n≥3). A vehicle's center is defined as the center point, around which other vehicles rotate and turn; this vehicle is the master vehicle, and the others are auxiliary vehicles. For example… Figure 4 As shown, vehicle 1 is the main vehicle, and vehicles 2 and 3 are auxiliary vehicles.

[0047] The following is a brief explanation. Figure 4 The coordinated movement of the three AGV transport vehicles is as follows: First, the three AGV transport vehicles move in unison to the blue position, at which point vehicle 1 is the master vehicle, and vehicles 2 and 3 are the auxiliary vehicles. Next, vehicle 1 rotates and turns in place, while vehicles 2 and 3 rotate counterclockwise around the center of vehicle 1, moving to the pink position. Then, the three AGV transport vehicles move in unison in a straight line, moving to the black position, at which point vehicle 1 is the master vehicle, and vehicles 2 and 3 are the auxiliary vehicles. Finally, vehicles 2 and 3 rotate clockwise around the center of vehicle 1, moving to the red position.

[0048] like Figure 5 As shown, when the lead car / tail car is the main car, the main car is controlled to stop in place and all auxiliary cars are rotated and turned in place until the direction of the vehicle's forward movement is perpendicular to the transported component. Adjust the wheel steering of all auxiliary vehicles, control all auxiliary vehicles to make circular turning motions around the vehicle center of the main vehicle to the corresponding set position and then stop circular turning, while controlling the main vehicle to make stationary rotational turning motions. Then control all auxiliary vehicles to perform stationary rotation and steering movements, while controlling the main vehicle to continue stationary rotation and steering movements until the forward direction of all vehicles is parallel to the transport component, and then stop the stationary rotation and steering movements of the main vehicle and all auxiliary vehicles. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

[0049] When the lead / tail vehicle is the main vehicle, the above four-stage steering control is adopted. The first stage is that the main vehicle is stationary and the forward direction of all auxiliary vehicles is controlled. The second stage is that the main vehicle is stationary and the main vehicle performs circular turning motion with the vehicle center of the main vehicle as the turning center. The third stage is the forward direction control of the auxiliary vehicles and the main vehicle. The fourth stage is the control of the wheel steering angle of the auxiliary vehicles. Based on the circular turning motion with the vehicle center of the main vehicle as the turning center and the stationary rotation motion of each vehicle, the coordinated movement of multiple linked transport vehicles is finally realized.

[0050] Specifically, when the lead / tail car is the main vehicle, each stage includes two states: (1) State 1 involves three or more AGV transport vehicles moving in a straight line in coordination, with each vehicle maintaining a consistent longitudinal speed, such as... Figure 6 As shown in (a) of the diagram.

[0051] (2) In state 2, car 1 is the main car, and cars 2, 3, ... n are auxiliary cars. Car 1 is stationary, and cars 2, 3, ... n turn by rotating in place, such as... Figure 6 As shown in (b) of the diagram.

[0052] (3) In state 3, vehicles 2, 3, ... n rotate in place until the direction of vehicle movement is perpendicular to the transport component, such as Figure 7 As shown in (a) of the diagram.

[0053] (4) In state 4, vehicles 2, 3, ... n adjust their wheel steering using a circular steering method. Vehicles 2, 3, ... n use the center of vehicle 1 as the steering center and perform circular steering motion; vehicle 1 uses a stationary rotation steering method for steering motion, such as... Figure 7 As shown in (b) of the diagram.

[0054] like Figure 8 As shown, let the center of vehicle 1 be... The center of the two vehicles is The center of the three vehicles is The center of vehicle n is The distance between the center points of vehicles 1 and 2 is... The distance between the center points of vehicles 1 and 3 is .

[0055] The distance between the center points of car 1 and car n is .

[0056] The two cars are centered on the steering wheel. Perform a circular turning motion with a turning radius of... 3 cars around the center of rotation Perform a circular turning motion with a turning radius of... . This indicates the longitudinal speed of the three vehicles. This indicates the longitudinal speed of the three vehicles. Let n represent the longitudinal velocity of car n. This is to ensure the points are aligned during the vehicle's motion. ,point …point Cars 2, 3, ... n must always satisfy equation (12) during their circular turning motion, always on a straight line: (12) (5) In state 5, vehicles 2, 3...n use a single AGV to turn to this position using a circular turning method. Vehicle 1 continues to use a stationary rotational turning method for turning, such as... Figure 9 As shown in (a) of the diagram.

[0057] (6) In state 6, vehicles 2, 3...n use a single AGV transport vehicle to rotate and turn in place until they reach this position. Vehicle 1 uses the same rotation and turn method to rotate and turn until it reaches this position. Figure 9 As shown in (b) of the diagram.

[0058] (7) In state 7, vehicles 2, 3...n use a stationary rotation steering method for turning, from state 6 where the vehicle's forward direction is perpendicular to the transport component to state 7 where the vehicle's forward direction is parallel to the transport component. Vehicle 1 remains stationary, such as... Figure 10 As shown in (a) of the diagram.

[0059] (8) In state 8, vehicles 2, 3, ... n adjust their wheel steering angles so that the wheels face the direction of travel, completing the coordinated steering of the three AGV transport vehicles, such as... Figure 10 As shown in (b) of the diagram.

[0060] The coordinated steering of the three AGV transport vehicles requires the overall control of the steering angles and rotational speeds of the 12 wheels of the three vehicles, and ensures that the center motion error of the three AGV transport vehicles is less than the maximum sliding amount of the sliding bearing device in the sliding cavity. The vehicle three-linkage steering motion control system is designed according to the steering methods (1) to (8).

[0061] The above content describes in detail the linkage steering method for three or more AGV transport vehicles to move from the blue position to the pink position. The linkage control method for moving from the black state to the red state is similar to the above, except that the counterclockwise circular turning motion of vehicles 1 and 2 is changed to clockwise circular turning motion. The steering method is the same and will not be described in detail here.

[0062] In other embodiments, such as Figure 11As shown, when the intermediate vehicle is the main vehicle, the main vehicle is controlled to stop in place and all auxiliary vehicles are rotated and turned in place until the direction of vehicle movement is perpendicular to the transport component. The steering angle of all auxiliary vehicles is adjusted, and the vehicle center of the main vehicle is used as the steering center to perform circular turning motion. Control all auxiliary vehicles to perform circular turning motions to the set position, and the main vehicle to rotate and turn in place to the corresponding position and then stop rotating in place; then control all auxiliary vehicles to perform rotating and turning motions in place until the forward direction of all auxiliary vehicles is parallel to the transport component. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

[0063] When the intermediate vehicle is the main vehicle, the above three-stage steering control is adopted. In the first stage, the main vehicle is stationary, and all auxiliary vehicles perform circular turning motion with the vehicle center of the main vehicle as the turning center. The second stage is the forward direction control of the auxiliary vehicles and the main vehicle. The third stage is the control of the wheel steering angle of the auxiliary vehicles. Based on the circular turning motion with the vehicle center of the main vehicle as the turning center and the stationary rotation motion of each vehicle, the coordinated movement of multiple linked transport vehicles is finally realized.

[0064] For example, selecting a 2-vehicle center The turning center is set at vehicle 2. Vehicles 1, 3, ..., n perform circular turning motions with the center of vehicle 2 as the turning center. Here, the vehicle dimensions and the circular turning radius are assumed to be constants. The coordinated turning process of three or more AGVs is divided into three processes, each with two states, as detailed below: (1) State 1 involves three or more AGV transport vehicles moving in a straight line in coordination, with each vehicle maintaining a consistent longitudinal speed, such as... Figure 12 As shown in (a) of the diagram.

[0065] (2) In state 2, car 2 is the main car, and cars 1, 3, ..., n are auxiliary cars. Car 2 is stationary, and cars 1, 3, ..., n use a stationary rotation steering method to turn, such as... Figure 12 As shown in (b) of the diagram.

[0066] (3) In state 3, vehicles 1, 3, ... n rotate in place until their forward direction is perpendicular to the transport component. Simultaneously, the steering angle of each wheel is changed, employing a circular steering method. Vehicles 1, 3, ... n use the center of vehicle 2 as the steering center and perform circular steering motion, such as... Figure 13 As shown in (a) of the diagram.

[0067] (4) In state 4, cars 1 and 3...n make circular turning motions to the designated position, while car 2 uses a stationary rotation turning method to turn to the designated position, such as... Figure 13 As shown in (b) of the diagram.

[0068] like Figure 14 As shown, let the center of vehicle 1 be... The center of the two vehicles is The center of the three vehicles is The center of vehicle n is The distance between the center points of vehicles 1 and 2 is... The distance between the center points of vehicles 2 and 3 is The distance between the center points of cars 2 and n is... .

[0069] 1 car with the center of steering Perform a circular turning motion with a turning radius of... 3 cars around the center of rotation Perform a circular turning motion with a turning radius of... The n-car is centered on the steering wheel. Perform a circular turning motion with a turning radius of... . This represents the longitudinal speed of vehicle 1. This indicates the longitudinal speed of the three vehicles. Let n represent the longitudinal velocity of car n. This is to ensure the points are aligned during the vehicle's motion. ,point and points … Cars 1, 3, ..., n must always satisfy equation (13) during their circular turning motion, always on a straight line: (13) (5) In state 5, vehicles 1, 3, ... n use a stationary rotation steering method for turning, changing from state 4 where the vehicle's forward direction is perpendicular to the transport component to state 5 where the vehicle's forward direction is parallel to the transport component. Vehicle 2 remains stationary, as... Figure 15 As shown in (a) of the diagram.

[0070] (6) In state 6, vehicles 1, 2, 3...n adjust their wheel steering angles so that the wheels face the direction of vehicle movement, completing the coordinated steering of the three AGVs, such as... Figure 15 As shown in (b) of the diagram.

[0071] The above-mentioned coordinated steering of n AGV vehicles requires the overall control of the steering angles and rotational speeds of the 4n wheels of the three vehicles, and ensures that the motion error of the center point of the n vehicles is less than the maximum sliding amount of the sliding bearing device in the sliding cavity. The vehicle three-linkage steering motion control system is controlled according to the steering methods (1) to (6).

[0072] In other embodiments, the vehicle corresponding to the in-situ turning center of the multi-linked transport vehicle is determined by the obstacle information within the confined space and the positions of each vehicle in the multi-linked transport vehicle. This improves the movement efficiency of the multi-linked transport vehicle.

[0073] In one or more embodiments, such as Figure 16 As shown, a steering control system for multi-linkage transport vehicles suitable for confined spaces is provided, which includes: The vehicle speed control module is used to obtain the center coordinates of each vehicle of the multi-linked transport vehicle and the longitudinal speed of each vehicle in real time during the turning process, and to control the center of each vehicle of the multi-linked transport vehicle to always keep collinear and the longitudinal speed of all vehicles to be consistent. The steering motion module is used to determine the vehicle corresponding to the stationary turning center of the multi-linked transport vehicle as the main vehicle, and the other vehicles as auxiliary vehicles, and control all auxiliary vehicles to perform corresponding circular turning motions with the main vehicle as the center. In the steering motion module, when the in-situ steering center of the multi-linked transport vehicle is the lead vehicle / tail vehicle, the lead vehicle / tail vehicle is the master vehicle and the other vehicles are auxiliary vehicles, and all auxiliary vehicles are controlled to perform circular steering motion in the same direction around the master vehicle simultaneously; when the in-situ steering center of the multi-linked transport vehicle is the middle vehicle, the middle vehicle is the master vehicle and the other vehicles are auxiliary vehicles, and all auxiliary vehicles are controlled to perform circular steering motion in the opposite direction around the master vehicle.

[0074] In this embodiment of the invention, during the circular steering motion in the steering module, the rotational angular velocity of the vehicle center of each auxiliary vehicle and the rotational angular velocity of each wheel center of each auxiliary vehicle around the main vehicle are equal.

[0075] When the intermediate vehicle is the main vehicle, the main vehicle is controlled to stop in place and all auxiliary vehicles are rotated and turned in place until the direction of vehicle movement is perpendicular to the transport component. The steering angle of all auxiliary vehicles is adjusted, and the vehicle center of the main vehicle is used as the steering center to perform circular turning motion. Control all auxiliary vehicles to perform circular turning motions to the set position, and the main vehicle to rotate and turn in place to the corresponding position and then stop rotating in place; then control all auxiliary vehicles to perform rotating and turning motions in place until the forward direction of all auxiliary vehicles is parallel to the transport component. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

[0076] When the lead car / tail car is the main vehicle, control the main vehicle to stop in place and all auxiliary vehicles to rotate and turn in place until the direction of vehicle movement is perpendicular to the transported component. Adjust the wheel steering of all auxiliary vehicles, control all auxiliary vehicles to make circular turning motions around the vehicle center of the main vehicle to the corresponding set position and then stop circular turning, while controlling the main vehicle to make stationary rotational turning motions. Then control all auxiliary vehicles to perform stationary rotation and steering movements, while controlling the main vehicle to continue stationary rotation and steering movements until the forward direction of all vehicles is parallel to the transport component, and then stop the stationary rotation and steering movements of the main vehicle and all auxiliary vehicles. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

[0077] In a specific embodiment, during the stationary rotational steering motion in the steering module, the steering angles of all wheels of the vehicle are equal.

[0078] In one or more embodiments, a multi-linkage transport vehicle steering control system suitable for confined spaces is provided, which includes a main controller and individual vehicle controllers that are respectively communicatively connected to the main controller. The single-vehicle controller is configured to control the corresponding vehicle in the multi-linkage transport vehicle to perform in-situ rotational turning and circular turning movements; the main controller is configured to perform the above-described actions. Figure 1 The steps shown are part of a steering control method for multi-linkage transport vehicles applicable to confined spaces. In this multi-unit transport vehicle, each vehicle has a sliding cavity 1 on its upper surface. A load-bearing structure is installed within each sliding cavity 1. The load-bearing structure includes a sliding load-bearing device 2 and a rotating load-bearing device 3. The sliding load-bearing device 2 is engaged within the sliding cavity 1, and the rotating load-bearing device 3 is rotatably connected to the sliding load-bearing device 2. Figure 17 As shown. Figure 18 In the diagram, (a) and (b) are the front view and sectional view of the load-bearing structure, respectively. According to... Figure 18 As can be seen in (b), the load-bearing structure is installed on the vehicle body 4, and the wheels 5 are installed at the bottom of the vehicle body.

[0079] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0080] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0081] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0082] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0083] Those skilled in the art will understand that all or part of the processes in 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.

[0084] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A steering control method for multi-linkage transport vehicles suitable for confined spaces, characterized in that, Each vehicle in the multi-link transport vehicle has a sliding cavity on its upper surface. A load-bearing structure is installed inside the sliding cavity. The load-bearing structure includes a sliding load-bearing device and a rotating load-bearing device. The sliding load-bearing device is engaged within the sliding cavity, and the rotating load-bearing device is rotatably connected to the sliding load-bearing device. The structure includes: During the turning process, the center coordinates of each vehicle of the multi-linked transport vehicle and the longitudinal speed of each vehicle are obtained in real time, and the centers of each vehicle of the multi-linked transport vehicle are kept collinear and the longitudinal speed of all vehicles is kept consistent. The vehicle corresponding to the stationary turning center of the multi-linked transport vehicle is designated as the main vehicle, and the other vehicles are designated as auxiliary vehicles. All auxiliary vehicles are controlled to perform corresponding circular turning movements around the main vehicle. Specifically, when the stationary turning center of the multi-linked transport vehicle is the lead vehicle / tail vehicle, the lead vehicle / tail vehicle is the master vehicle, and the other vehicles are auxiliary vehicles. All auxiliary vehicles are controlled to simultaneously perform circular turning motions around the master vehicle in the same direction. When the stationary turning center of the multi-linked transport vehicle is the middle vehicle, the middle vehicle is the master vehicle, and the other vehicles are auxiliary vehicles. The master vehicle is controlled to stop in place, and all auxiliary vehicles are controlled to rotate and turn in place until the vehicle's forward direction is perpendicular to the transport component. The wheel steering angles of all auxiliary vehicles are adjusted, and circular turning motions are performed with the center of the master vehicle as the turning center.

2. The steering control method for multi-linkage transport vehicles suitable for confined spaces as described in claim 1, characterized in that, During the circular turning motion, the rotational angular velocity of the vehicle center of each auxiliary vehicle and the rotational angular velocity of each wheel center of each auxiliary vehicle around the main vehicle are all equal.

3. The steering control method for multi-linkage transport vehicles suitable for confined spaces as described in claim 1, characterized in that, When the intermediate car is the main car, control all auxiliary cars to make circular turning movements to the set position. After the main car rotates and turns to the corresponding position, it stops rotating in place. Then control all auxiliary cars to make rotating turning movements in place until the forward direction of all auxiliary cars is parallel to the transport component. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

4. The steering control method for multi-linkage transport vehicles suitable for confined spaces as described in claim 1, characterized in that, When the lead car / tail car is the main vehicle, control the main vehicle to stop in place and all auxiliary vehicles to rotate and turn in place until the direction of vehicle movement is perpendicular to the transported component. Adjust the wheel steering of all auxiliary vehicles, control all auxiliary vehicles to make circular turning motions around the vehicle center of the main vehicle to the corresponding set position and then stop circular turning, while controlling the main vehicle to make stationary rotational turning motions. Then control all auxiliary vehicles to perform stationary rotation and steering movements, while controlling the main vehicle to continue stationary rotation and steering movements until the forward direction of all vehicles is parallel to the transport component, and then stop the stationary rotation and steering movements of the main vehicle and all auxiliary vehicles. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

5. The steering control method for multi-linkage transport vehicles suitable for confined spaces as described in claim 3 or 4, characterized in that, During the stationary rotation and steering motion, the steering angles of all wheels of the vehicle are equal.

6. The steering control method for multi-linkage transport vehicles suitable for confined spaces as described in claim 1, characterized in that, The vehicle corresponding to the in-situ turning center of the multi-linked transport vehicle is determined by the obstacle information in the confined space and the positions of each vehicle in the multi-linked transport vehicle.

7. A steering control system for multi-linkage transport vehicles suitable for confined spaces, characterized in that, Each vehicle in the multi-link transport vehicle has a sliding cavity on its upper surface. A load-bearing structure is installed inside the sliding cavity. The load-bearing structure includes a sliding load-bearing device and a rotating load-bearing device. The sliding load-bearing device is engaged within the sliding cavity, and the rotating load-bearing device is rotatably connected to the sliding load-bearing device. The structure includes: The vehicle speed control module is used to obtain the center coordinates of each vehicle of the multi-linked transport vehicle and the longitudinal speed of each vehicle in real time during the turning process, and to control the center of each vehicle of the multi-linked transport vehicle to always keep collinear and the longitudinal speed of all vehicles to be consistent. The steering motion module is used to determine the vehicle corresponding to the stationary turning center of the multi-linked transport vehicle as the main vehicle, and the other vehicles as auxiliary vehicles, and control all auxiliary vehicles to perform corresponding circular turning motions with the main vehicle as the center. Specifically, when the stationary turning center of the multi-linked transport vehicle is the lead vehicle / tail vehicle, the lead vehicle / tail vehicle is the master vehicle, and the other vehicles are auxiliary vehicles. All auxiliary vehicles are controlled to simultaneously perform circular turning motions around the master vehicle in the same direction. When the stationary turning center of the multi-linked transport vehicle is the middle vehicle, the middle vehicle is the master vehicle, and the other vehicles are auxiliary vehicles. The master vehicle is controlled to stop in place, and all auxiliary vehicles are controlled to rotate and turn in place until the vehicle's forward direction is perpendicular to the transport component. The wheel steering angles of all auxiliary vehicles are adjusted, and circular turning motions are performed with the center of the master vehicle as the turning center.

8. The multi-linkage transport vehicle steering control system suitable for confined spaces as described in claim 7, characterized in that, During the circular turning motion, the rotational angular velocity of the vehicle center of each auxiliary vehicle and the rotational angular velocity of each wheel center of each auxiliary vehicle around the main vehicle are all equal.

9. The multi-linkage transport vehicle steering control system suitable for confined spaces as described in claim 7, characterized in that, When the intermediate car is the main car, control all auxiliary cars to make circular turning movements to the set position. After the main car rotates and turns to the corresponding position, it stops rotating in place. Then control all auxiliary cars to make rotating turning movements in place until the forward direction of all auxiliary cars is parallel to the transport component. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

10. The multi-linkage transport vehicle steering control system suitable for confined spaces as described in claim 7, characterized in that, When the lead car / tail car is the main vehicle, control the main vehicle to stop in place and all auxiliary vehicles to rotate and turn in place until the direction of vehicle movement is perpendicular to the transported component. Adjust the wheel steering of all auxiliary vehicles, control all auxiliary vehicles to make circular turning motions around the vehicle center of the main vehicle to the corresponding set position and then stop circular turning, while controlling the main vehicle to make stationary rotational turning motions. Then control all auxiliary vehicles to perform stationary rotation and steering movements, while controlling the main vehicle to continue stationary rotation and steering movements until the forward direction of all vehicles is parallel to the transport component, and then stop the stationary rotation and steering movements of the main vehicle and all auxiliary vehicles. Keep the main vehicle stationary, adjust the steering angle of all auxiliary vehicles so that the wheels of all auxiliary vehicles are facing the direction of travel, thus completing the steering control of the multi-link transport vehicle.

11. The multi-linkage transport vehicle steering control system suitable for confined spaces as described in claim 9 or 10, characterized in that, During the stationary rotation and steering motion, the steering angles of all wheels of the vehicle are equal.

12. A steering control system for multi-linkage transport vehicles suitable for confined spaces, characterized in that, This includes the main controller and individual vehicle controllers that are connected to it in communication. The single-vehicle controller is configured to control the corresponding vehicle in the multi-linked transport vehicle to perform in-situ rotational turning motion and circular turning motion; the main controller is configured to execute the multi-linked transport vehicle steering control method applicable to confined spaces as described in any one of claims 1-6; Each vehicle in the multi-linkage transport vehicle has a sliding cavity on its upper surface. A load-bearing structure is installed in the sliding cavity. The load-bearing structure includes a sliding load-bearing device and a rotating load-bearing device. The sliding load-bearing device is locked in the sliding cavity, and the rotating load-bearing device is rotatably connected to the sliding load-bearing device.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by the processor, the program implements the steering control method for multi-linkage transport vehicles applicable to confined spaces as described in any one of claims 1-6.

14. A computer device 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 program, it implements the steering control method for multi-linkage transport vehicles suitable for confined spaces as described in any one of claims 1-6.

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