Mobile robot, motion positioning control method, device and system thereof and medium

Abstract

The invention discloses a mobile robot, a motion positioning control method, device and system thereof and a medium, and relates to the technical field of engineering machinery. The method comprises the following steps: when a mobile robot reaches a deviation threshold range of a target point position, according to point cloud data obtained by emitting line structured light to a target workpiece, carrying out posture adjustment, so that the emitted line structured light is aligned with the target workpiece; and after the posture adjustment, the mobile robot is controlled to linearly move parallel to the target workpiece and continuously emit the linear structured light, and the transverse position of the mobile robot relative to the target workpiece is adjusted according to the position change of the continuously emitted linear structured light relative to the target workpiece, so that the mobile robot reaches the target point position. According to the embodiment of the invention, the posture of the mobile robot is adjusted in combination with the line structured light, the mobile robot is controlled to move transversely, fine positioning of the mobile robot is realized, and the method can adapt to more scenes.

Description

Technical Field

[0001] The present application relates to the technical field of engineering machinery, and in particular to a mobile robot and a motion positioning control method, device, system and medium thereof. Background Art

[0002] In the field of engineering machinery, the application of a large number of industrial robots has replaced some high-intensity, batch manual operations, but there are still problems that have not been solved. Taking welding operations as an example, there are the following problems: 1) In open and semi-open structural spaces, there are still a large number of discrete, full-position, small-size welds that need to be welded manually; 2) Traditional industrial robots and their welding workstations have a spatial movement range limited by external tracks, so that the spatial working range is limited, and they are large in size, heavy in weight, and have high costs and energy consumption.

[0003] In this regard, mobile robots are favored because of their lightness, flexibility, convenience, and portability. For example, for discrete and all-position welds on large structures, the previous large, heavy, high-cost, and high-energy gantry machine structure has been changed to a light, flexible, low-cost, and low-energy mobile welding robot, which greatly increases the robot's operating space range, saves site space, and reduces cost investment.

[0004] At present, there are many methods for mobile robot motion positioning, such as electromagnetic guidance navigation. This method requires laying electromagnetic tracks on the ground, which is troublesome to lay and difficult to change and expand the path. Another example is QR code guidance. This method uses a camera to scan the ground QR code to obtain the current position information, but a large number of QR codes need to be laid on site, and the QR codes are easy to wear and tear, and the maintenance cost is high. Another example is visual navigation. The image information of the operating area is obtained by the on-board visual sensor to achieve navigation. This method requires texture information of the ground, and due to the limited field of view of the visual sensor, it is only suitable for small-field movement. Another example is laser radar navigation. By scanning the environment for modeling and specifying the target position, large-field navigation positioning and obstacle avoidance can be achieved, but the navigation positioning of this method requires the target position point to be specified in advance, and is limited by the accuracy of the sensor, so the positioning accuracy is not high. Others include GPS navigation, inertial navigation, etc., and these methods often have large accuracy errors.

[0005] Therefore, new mobile robot motion positioning control schemes are needed. Summary of the invention

[0006] The purpose of the embodiments of the present application is to provide a mobile robot and a motion positioning control method, device, system and medium thereof, so as to at least partially solve the above-mentioned technical problems.

[0007] In order to achieve the above-mentioned objectives, the first aspect of the present application provides a motion positioning control method for a mobile robot, comprising: when the mobile robot reaches a deviation threshold range of a target point position, adjusting the posture of the mobile robot according to point cloud data obtained by the mobile robot emitting line structured light to a target workpiece, so that the emitted line structured light is aligned with the target workpiece; and after the posture adjustment, controlling the mobile robot to move in a straight line parallel to the target workpiece and continuously emitting line structured light, and adjusting the lateral position of the mobile robot relative to the target workpiece according to the position change of the continuously emitted line structured light relative to the target workpiece, so that the mobile robot reaches the target point position.

[0008] In an embodiment of the present application, the deviation threshold range is determined so that when the target workpiece is placed within the specified threshold area, it is within the field of view corresponding to the line structured light.

[0009] In an embodiment of the present application, during the process of the mobile robot reaching the target point position within the deviation threshold range, the motion positioning control method further includes: determining a proposed virtual wheel angle according to a deviation factor between an actual path of the mobile robot and a planned path, wherein the virtual wheel is located in the middle position of a pair of actual walking wheels of the mobile robot; solving the actual walking wheel angle of the mobile robot according to the determined virtual wheel angle; and performing path tracking according to the actual walking wheel angle to control the mobile robot to reach the target point position within the deviation threshold range.

[0010] In an embodiment of the present application, the posture adjustment of the mobile robot includes: performing straight line fitting on the point cloud data, and selecting a first straight line from the fitted straight lines; translating the first straight line along the Z axis of the line structured light plane coordinate system to obtain a second straight line intersecting with the X axis of the line structured light plane coordinate system, wherein the optical axis corresponding to the line structured light is the Z axis, and the axis perpendicular to the Z axis is the X axis; obtaining the angle between the second straight line and the X axis of the line structured light plane coordinate system as the body rotation angle; and controlling the mobile robot to rotate the body rotation angle in situ around the body axis to complete the posture adjustment.

[0011] In an embodiment of the present application, adjusting the lateral position of the mobile robot relative to the target workpiece includes: determining a transverse straight line where the line structured light plane intersects the outer surface of the target workpiece; and controlling the mobile robot to move along the direction of the transverse straight line based on the current position of the mobile robot and the position change of the current line structured light relative to the transverse straight line, so that the mobile robot reaches the target point position.

[0012] In an embodiment of the present application, the motion positioning control method also includes: determining the length of the transverse straight line as the width of the target workpiece based on the moving distance of the mobile robot along the direction of the transverse straight line and the distance between the endpoint of the transverse straight line and the optical axis point of the current line structured light on the transverse straight line; and determining the model of the target workpiece based on the width of the target workpiece.

[0013] In an embodiment of the present application, controlling the mobile robot to move in the direction of the transverse straight line includes: a first movement control step, in which, when the line structured light emitted by the mobile robot at the current position after the posture adjustment covers the first endpoint of the transverse straight line but cannot cover the second endpoint of the transverse straight line, the mobile robot is controlled to move in a first direction until the corresponding line structured light covers the second endpoint of the transverse straight line, and the mobile robot is controlled to stop, wherein the first direction is the direction from the first endpoint to the second endpoint, and the second direction is opposite to the first direction; and a second movement control step, controlling the mobile robot to turn to the second direction and move until the optical axis point of the corresponding line structured light coincides with the midpoint of the transverse straight line, and the mobile robot is controlled to stop, wherein the position of the mobile robot when the coincidence occurs is the target point position.

[0014] In an embodiment of the present application, the controlling the mobile robot to move along the direction of the transverse straight line also includes: a third movement control step, in which, when the line structured light emitted by the mobile robot at the current position after the posture adjustment cannot cover any endpoint of the transverse straight line and does not generate point cloud data, the mobile robot is controlled to move along the first direction until the corresponding line structured light covers the first endpoint, and the first movement control step is started; and a fourth movement control step, in which, when the line structured light emitted by the mobile robot at the current position after the posture adjustment cannot cover any endpoint of the transverse straight line and can generate point cloud data, the mobile robot is controlled to move along the second direction until the corresponding line structured light covers the first endpoint, and the first movement control step is started.

[0015] A second aspect of the present application provides a motion positioning control device for a mobile robot, comprising: a memory configured to store instructions; and a processor configured to call the instructions from the memory and to implement any of the above-mentioned motion positioning control methods when executing the instructions.

[0016] The third aspect of the present application provides a motion positioning control system for a mobile robot, comprising: a sensor component, which includes at least a line structured light sensor installed on the mobile robot, for emitting line structured light to scan the surface of a target workpiece to obtain corresponding point cloud data; and the above-mentioned motion positioning control device, which is used to control the mobile robot to move to the target point position according to the point cloud data.

[0017] In an embodiment of the present application, the sensing component also includes a multi-line laser radar sensor and / or an ultrasonic sensor installed on the mobile robot, wherein the multi-line laser radar sensor is used to assist the mobile robot in path planning, obstacle avoidance or positioning, and the ultrasonic sensor is used to assist the mobile robot in obstacle avoidance.

[0018] A fourth aspect of the present application provides a mobile robot, comprising any of the above-mentioned motion positioning control systems of the mobile robot.

[0019] A fifth aspect of the present application provides a machine-readable storage medium having instructions stored thereon, the instructions being used to enable a machine to execute any of the above-mentioned motion positioning control methods for a mobile robot.

[0020] Through the above technical scheme, the embodiment of the present application combines line structured light to adjust the posture of the mobile robot and control the lateral movement of the mobile robot, so that the mobile robot finally reaches the target point position, thereby realizing precise positioning of the mobile robot. There is no need to additionally set up electromagnetic tracks, ground QR codes, vehicle-mounted visual sensors and various navigation equipment, etc., which not only improves the positioning accuracy, but also can adapt to more scenarios.

[0021] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. In the accompanying drawings:

[0023] Figure 1 A schematic diagram of a flow chart of a motion positioning control method for a mobile robot according to an embodiment of the present application is schematically shown;

[0024] Figure 2 A schematic diagram of the structure of a mobile welding robot system according to an example of an embodiment of the present application is shown;

[0025] Figure 3 A schematic diagram of rough positioning of a mobile welding robot according to an example of an embodiment of the present application is schematically shown;

[0026] Figure 4 The main flow chart of the motion positioning control of an example mobile welding robot according to an embodiment of the present application is schematically shown;

[0027] Figure 5 A flowchart schematically shows a navigation motion precision positioning control strategy adopted by an example mobile welding robot according to an embodiment of the present application;

[0028] Figure 6 A schematic diagram schematically shows a path tracking of a mobile welding robot according to an example of an embodiment of the present application;

[0029] Figure 7 The schematic diagram shows a displacement tracking angle calculation principle diagram of a mobile welding robot according to an example of an embodiment of the present application;

[0030] Figure 8 A schematic diagram of point cloud straight line fitting according to an example of an embodiment of the present application is schematically shown;

[0031] Fig. 9 A schematic diagram schematically shows the posture adjustment of a mobile chassis according to an example of an embodiment of the present application;

[0032] Fig.10 A schematic diagram schematically shows the lateral movement of a robot according to an example of an embodiment of the present application;

[0033] Figure 11(1)-Figure 11(4) A schematic diagram schematically shows a robot movement control principle in a first scenario according to an example of an embodiment of the present application;

[0034] Figure 12(1)-Figure 12(4) A schematic diagram schematically shows a robot movement control principle in a second scenario according to an example of an embodiment of the present application;

[0035] Fig.13 A schematic diagram schematically shows a structure of motion positioning control of a mobile robot according to an embodiment of the present application; and

[0036] Fig.14 The structural block diagram of a motion positioning control system of a mobile robot according to an embodiment of the present application is schematically shown.

[0037] Description of Reference Numerals

[0038] 100 sensor component 200 motion positioning control device

[0039] 1 Box steel structure 2 Structured light beam

[0040] 3 Weld seam tracking sensor 4 Welding robot arm and welding gun

[0041] 5-line LiDAR sensor 6-line structured light sensor

[0042] 7 Ultrasonic sensor 8 Mobile chassis

[0043] 9 Welding machine and welding system 10 Rope winding mechanism

[0044] 11 Power supply line 12 Power supply column

[0045] 13 Threshold area range 14 Deviation threshold range DETAILED DESCRIPTION

[0046] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the specific implementation methods described herein are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0047] It should be noted that the acquisition, transmission, storage, use, and processing of data in the technical solution of this application are in compliance with the relevant provisions of national laws and regulations. In the embodiments of this application, some existing solutions in the industry such as certain software, components, and models may be mentioned, which should be considered as exemplary. Their purpose is only to illustrate the feasibility of implementing the technical solution of this application, but it does not mean that the applicant has or will necessarily use the solution.

[0048] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0049] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0050] Figure 1The following is a schematic diagram showing a flow chart of a motion positioning control method of a mobile robot according to an embodiment of the present application. Figure 1 As shown, the motion positioning control method may include the following steps S100-S200.

[0051] Step S100, when the mobile robot reaches the deviation threshold range of the target point position, the mobile robot is adjusted according to the point cloud data obtained by the mobile robot emitting line structured light to the target workpiece, so that the emitted line structured light is aimed at the target workpiece.

[0052] Among them, "controlling the mobile robot to reach the target point position within the deviation threshold range" belongs to the rough positioning of the mobile robot. And, the emitted line structured light is aligned with the target workpiece, specifically, the optical axis of the line structured light is perpendicular to the irradiated outer surface of the target workpiece. Therefore, step S100 is to adjust the posture of the mobile robot on the basis of the rough positioning of the mobile robot, so that the line structured light emitted by the mobile robot can be vertically irradiated to the outer surface of the target workpiece.

[0053] Step S200, after the posture adjustment, control the mobile robot to move in a straight line parallel to the target workpiece and continuously emit line structured light, and adjust the lateral position of the mobile robot relative to the target workpiece according to the position change of the continuously emitted line structured light relative to the target workpiece, so that the mobile robot reaches the target point position.

[0054] That is, after step S100, the mobile robot is already within the deviation threshold range of the target point position, and the emitted line structured light can vertically illuminate the outer surface of the target workpiece, so that in step S200, the mobile robot is controlled to move laterally according to the position change of the continuously emitted line structured light relative to the target workpiece, so that the mobile robot finally reaches the target point position, and the mobile robot is precisely positioned. In this process, the posture adjustment and precise positioning of the mobile robot are performed by line structured light, and there is no need to set up additional electromagnetic tracks, ground QR codes, vehicle-mounted visual sensors, and various navigation devices, which not only improves the positioning accuracy, but also can adapt to more scenarios.

[0055] Below Figure 2-Figure 12(4) Taking the welding operation performed by the mobile welding robot shown as an example, the application of the above-mentioned motion positioning control method in the embodiment of the present application is specifically introduced.

[0056] Figure 2 The structure diagram of a mobile welding robot system according to an example of an embodiment of the present application is schematically shown. Figure 2As shown, the entire mobile welding robot system consists of a large box steel structure 1, a structured light beam 2, a weld tracking sensor 3, a welding robot arm and a welding gun 4, a multi-line laser radar sensor 5, a large field of view line structured light sensor 6, an ultrasonic sensor 7, a mobile chassis 8, a welding machine and a welding system 9, a rope winding and hoisting mechanism 10, a power supply line 11 and a power column 12.

[0057] in, Figure 3 The schematic diagram of the rough positioning of the mobile welding robot according to the example of the embodiment of the present application is schematically shown. Figure 2 and Figure 3 , the large box steel structure 1 is placed arbitrarily within the threshold area range 13, the coordinate system origin O of the multi-line laser radar sensor 5 is on the mid-vertical line of the mobile chassis 8, and the mobile chassis 8 uses the multi-line laser radar sensor 5 to model the large scene environment and specify the target point position B. A set of path tracking PID navigation control algorithms can be developed for the multi-line laser radar sensor 5 to assist in controlling the mobile chassis 8 to navigate, avoid obstacles and roughly locate at any position in the workshop (starting point A). The ultrasonic sensor 7 is used to assist in controlling the mobile chassis 8 to avoid obstacles and reduce blind spots. When the mobile chassis 8 moves in the path planned by the multi-line laser radar sensor 5, the ultrasonic sensor 7 and the multi-line laser radar sensor 5 detect obstacles, and can assist in controlling the mobile chassis 8 to bypass the obstacles and move to the target point position B. The power supply line 11 of the mobile chassis 8 and the welding machine and welding system 9 is connected to the power column 12 through the rope winding hoisting mechanism 10. The rope winding hoisting mechanism 10 matches the moving speed of the mobile chassis 8 to release and wind the power supply line 11. The rope winding hoisting mechanism 10 can rotate freely within 360° around its own base following the mobile chassis 8, ensuring that the angle of the rope winding hoisting mechanism 10 for releasing and winding the rope is always along the direction of the power supply line 11.

[0058] like Figure 3 As shown, the mobile chassis 8 navigates from the starting point A to the target point B. Since the navigation positioning deviation is within the deviation threshold range 14 and the placement position of the large box steel structure 1 is offset, and since the moving trajectory of the welding robot arm and the welding gun 4 is fixed, the welding position of the welding robot arm and the welding gun 4 is unreachable, and it is necessary to perform a secondary correction on the posture of the mobile chassis 8, that is, to perform the posture adjustment of the above step S100 and the precise positioning of the above step S200.

[0059] In a preferred embodiment of the present application, the deviation threshold range is determined so that when the target workpiece is placed within the specified threshold area, it is within the field of view corresponding to the line structured light. Figure 3In the example of FIG. 1 , the deviation threshold range 14 is determined so that when the large box steel structure 1 is placed in the threshold area range 13, it is in the field of view corresponding to the line structure light sensor 6. In this way, it can not only help solve the problem of low navigation positioning accuracy of the mobile chassis 8, but also realize the arbitrary placement of the large box steel structure 1 within the threshold area range 13.

[0060] Furthermore, for Figure 2 and Figure 3 Corresponding examples can develop a set of mobile welding robot navigation motion secondary precision positioning control strategies based on the motion positioning control method of the embodiment of the present application to improve the navigation positioning accuracy of the mobile chassis 8. It should be noted that when developing the secondary precision positioning control strategy, the preferred embodiment schemes of the present application are involved, and these schemes should also belong to the protection scope of the embodiments of the present application.

[0061] Specifically, Figure 4 The main flow chart of the motion positioning control of the mobile welding robot according to the embodiment of the present application is schematically shown. Figure 5 The flowchart of the navigation motion precision positioning control strategy adopted by the example mobile welding robot according to the embodiment of the present application is schematically shown. Figure 4 As shown, the following eight steps S1-S8 may be included, and each step is adaptively related to Figure 5 The steps of the navigation motion precision positioning control strategy are combined.

[0062] The first step S1 is to develop a path tracking control algorithm for a mobile welding robot to perform path navigation.

[0063] For example, Figure 6 The schematic diagram of the path tracking of the mobile welding robot according to the example of the embodiment of the present application is schematically shown. Figure 2 and Figure 3 In the example of , the mobile welding robot is a four-wheel vehicle, so it is also referred to as a vehicle in the following text. Figure 6 As shown, G XY is the world coordinate system; R XY is the moving coordinate system of the mobile chassis 8, which takes the geometric center of the vehicle as the origin; (Xg, Yg) is the point on the planned path closest to the geometric center of the vehicle, r represents the closest distance; θ is the deviation angle between the current vehicle route and the direction of the distance point on the road.

[0064] In a preferred embodiment of the present application, the adopted path tracking scheme includes: determining the rotation angle of the proposed virtual wheel according to the deviation factor between the actual path of the mobile robot and the planned path, wherein the virtual wheel is located in the middle position of a pair of actual walking wheels of the mobile robot; solving the rotation angle of the actual walking wheel of the mobile robot according to the determined rotation angle of the virtual wheel; and performing path tracking according to the rotation angle of the actual walking wheel to control the mobile robot to reach the target point position within the deviation threshold range.

[0065] For this path tracking scheme, Figure 6 For example, a virtual tire is proposed, and the virtual tire is located between tires M1 and M4. δ represents the turning angle of the virtual tire. After the large scene environment is modeled by the multi-line laser radar sensor 5, the optimal path is planned at the starting point A and navigated to the target point position B. Figure 6 As shown, the multi-line laser radar sensor 5 obtains r and θ in the actual path and the planned path. When r and θ are both 0, the turning angles of tires M1 and M4 are adjusted by the deviation of r and θ, where the deviation e(t) = r + θ. According to the classic PID, the turning angle δ of the virtual tire can be obtained as follows:

[0066]

[0067] Further, Figure 7 The schematic diagram of the displacement tracking angle calculation principle of the mobile welding robot according to the example of the embodiment of the present application is shown. The virtual tire angle δ obtained according to formula (1) is as follows: Figure 7 As shown, the real-time turning angle δ of the actual tire M1 can be obtained synchronously. 1 and the real-time turning angle δ of the actual tire M4 2 , thus achieving high-precision navigation tracking. The corresponding angle calculation formula is as follows:

[0068]

[0069] Where D and d are the wheelbases between the front and rear wheels and the left and right wheels, respectively, and equations (2) and (3) show the conventional Ackerman chassis tire steering angle solution method.

[0070] The accuracy of the mobile chassis 8 in navigating and positioning to the target point position B is tested experimentally, and the deviation threshold range 14 of navigation and positioning can be determined accordingly. Then, the threshold area range 13 for placing the large box steel structure 1 is determined according to the deviation threshold range 14 and the field of view of the large field line structure light sensor 6, so as to ensure that the mobile chassis 8 is within the deviation threshold range 14 for navigating to the target point position B. In this way, the large box steel structure 1 is arbitrarily placed within the threshold area range 13, which is within the field of view of the large field line structure light sensor 6.

[0071] In the second step S2, a single emission of line structured light is performed to scan the surface of the target workpiece.

[0072] like Figure 3 As shown, within the deviation threshold range of the target point position B, the large field of view line structured light sensor 6 is triggered once to obtain effective point cloud data of the outer surface of the large box steel structure 1 irradiated by light within the field of view.

[0073] After the second step, the preferred embodiment of the present application adjusts the posture of the mobile robot through the following steps: perform straight line fitting on the point cloud data, and select a first straight line from the fitted straight lines; translate the first straight line along the Z axis of the line structured light plane coordinate system to obtain a second straight line intersecting with the X axis of the line structured light plane coordinate system, wherein the optical axis corresponding to the line structured light is the Z axis, and the axis perpendicular to the Z axis is the X axis; obtain the angle between the second straight line and the X axis of the line structured light plane coordinate system as the body rotation angle; and control the mobile robot to rotate the body rotation angle in situ around the body axis to complete the posture adjustment. Among them, as Figure 8 , 9 As shown, the line structured light plane coordinate system is the XOZ coordinate system, with the line structured light emission point O as the origin, the optical axis of the line structured light as the Z axis, and the X axis perpendicular to the Z axis. Among them, it is easy to know that the X axis is equivalent to the edge line of the mobile robot. The line structured light emitted by the mobile robot in the initial posture cannot be aligned with the target workpiece, and after it rotates in situ around the fuselage axis by the fuselage rotation angle, it is equivalent to the X axis of the edge line of the mobile robot being parallel to the target workpiece, so that the emitted line structured light can be aligned with the target workpiece.

[0074] When this posture adjustment scheme is applied to the above example, it may specifically include the following third step S3, fourth step S4 and fifth step S5.

[0075] The third step S3 is to process the point cloud data.

[0076] Perform secondary processing on the point cloud data, for example, first use the density clustering DBSCN algorithm to classify the point cloud, and then perform the least squares method to fit the point cloud of each class. Figure 8 The schematic diagram of the point cloud straight line fitting according to the example of the embodiment of the present application is schematically shown. Figure 8 As shown, the line fg point cloud set with the largest number of point clouds is selected {(X c ,Z c ),(X c+1 ,Z c+1 ),……(X d ,Z d )}, and the straight line slope k can also be calculated. Wherein, the straight line fg is the first straight line in the preferred embodiment of the present application.

[0077] The fourth step S4 is to calculate the body rotation angle.

[0078] Fig. 9 The following is a schematic diagram of adjusting the posture of a mobile chassis according to an example of an embodiment of the present application. Figure 8 As shown, by scanning the outer surface of the large box steel structure 1 once through structured light triggering and point cloud algorithm processing, a straight line fg is obtained in the coordinate system O of the large field of view line structured light sensor 6, and the straight line fg is translated along the Z axis to the point f' intersecting with the X axis to obtain a straight line f ′ g ′ , the straight line f ′ g ′ This is the second straight line in the preferred embodiment of the present application. According to the slope k, we can obtain Figure 8 The straight line f ′ The angle between g′ and the X-axis of the large field of view line structured light sensor 6 is:

[0079] θ=tan -1 k (4)

[0080] The fifth step S5 is to adjust the vehicle body posture.

[0081] Figure 8 The straight line f ′ The angle θ between g′ and the X-axis of the large field of view line structured light sensor 6 is the angle at which the mobile chassis 8 needs to rotate in situ around the axis of the vehicle body. If θ>0, the mobile chassis 8 rotates in situ clockwise around the axis of the vehicle body by θ°. If θ<0, the mobile chassis 8 rotates in situ counterclockwise around the axis of the vehicle body by θ° to achieve the posture adjustment of the mobile chassis 8 and obtain the position C. Fig. 9 As shown, after rotating θ°, the straight line f obtained in the new posture ′ g′ is parallel to the edge line of the mobile robot and the target workpiece.

[0082] After completing the posture adjustment in the fifth step, a preferred embodiment of the present application adjusts the lateral position of the mobile robot relative to the target workpiece to achieve precise positioning through the following steps: determining a transverse straight line where the line structured light plane intersects the outer surface of the target workpiece; and according to the current position of the mobile robot and the position change of the current line structured light relative to the transverse straight line, controlling the mobile robot to move along the direction of the transverse straight line so that the mobile robot reaches the target point position.

[0083] When this precise positioning solution is applied to the above example, it may specifically include the following sixth step S6, seventh step S7 and eighth step S8.

[0084] In the sixth step S6, a transverse straight line where the line structured light plane intersects the outer surface of the target workpiece is determined.

[0085] After adjusting the body posture of the mobile chassis 8 , the large-field-of-view line structured light sensor 6 is continuously triggered to scan the outer surface of the large box steel structure 1 . Fig.10 The schematic diagram of the lateral movement of the robot according to the example of the embodiment of the present application is schematically shown. In which, the large field of view line structured light sensor 6 is set with the origin O coordinate system, the plane composed of the X and Z axes, that is, the line structured light plane coordinate system mentioned above. Through this coordinate system, the transverse straight line intersecting the outer surface of the large box steel structure 1 is ab, and the midpoint of ab is e.

[0086] The seventh step S7 is to implement precise positioning.

[0087] After determining the transverse straight line where the line structured light plane intersects the outer surface of the target workpiece in the sixth step, further determine the current position of the mobile robot and the position change of the current line structured light relative to the transverse straight line to control the mobile robot to move along the direction of the transverse straight line. In a preferred embodiment of the present application, controlling the mobile robot to move along the direction of the transverse straight line may include the following first movement control step and second movement control step.

[0088] The first movement control step is to control the mobile robot to move along a first direction when the line structured light emitted by the mobile robot at the current position after the posture adjustment covers the first endpoint of the transverse straight line but cannot cover the second endpoint of the transverse straight line, and then control the mobile robot to stop when the corresponding line structured light covers the second endpoint of the transverse straight line, wherein the first direction is the direction from the first endpoint to the second endpoint, and the second direction is opposite to the first direction.

[0089] The second movement control step controls the mobile robot to turn and move in the second direction until the optical axis point of the corresponding line structured light coincides with the midpoint of the transverse straight line, and then controls the mobile robot to stop, wherein the position of the mobile robot when the coincidence occurs is the target point position.

[0090] Furthermore, in another preferred embodiment, the following third movement control step and fourth movement control step may also be included.

[0091] The third movement control step is to control the mobile robot to move along the first direction when the line structured light emitted by the current position of the mobile robot after the posture adjustment cannot cover any endpoint of the cross-sectional straight line and does not generate point cloud data, and start executing the first movement control step until the corresponding line structured light covers the first endpoint.

[0092] The fourth movement control step is to control the mobile robot to move along the second direction when the line structured light emitted by the current position of the mobile robot after the posture adjustment cannot cover any endpoint of the transverse straight line and can generate point cloud data, until the corresponding line structured light covers the first endpoint, and then start to execute the first movement control step.

[0093] In addition, in the process of executing any of the above-mentioned movement control steps, the motion positioning control method of the preferred embodiment of the present application may also include: determining the length of the transverse straight line as the width of the target workpiece based on the movement distance of the mobile robot along the direction of the transverse straight line and the distance between the endpoint of the transverse straight line and the optical axis point of the current line structured light on the transverse straight line; and determining the model of the target workpiece based on the width of the target workpiece.

[0094] Now let's go back to the example of step 7 and specifically introduce the control scenarios corresponding to the above four mobile control steps. In step 7, according to step 5, after the mobile chassis 8 adjusts the body posture, it obtains position C. At this time, the large field of view line structured light sensor 6 is continuously triggered, and the current line structured light (light cd) emitted continuously will appear in the following situations:

[0095] (1) Corresponding to the first movement control step, as shown in FIG11(1), if the position C of the mobile chassis 8 is on the ae side, point c is on the left side of point a, and point a is on the left side of the origin O, the large field of view line structured light sensor 6 is turned off, and the mobile chassis 8 is in a stationary state. The large field of view line structured light sensor 6 is triggered once, and the distance of point a to the line segment ao in the large field of view line structured light sensor 6 is recorded. The large field of view line structured light sensor 6 is continuously triggered, and the mobile chassis 8 is controlled to move along Direction of linear motion. When point d in the light cd emitted by the large field of view line structured light sensor 6 is to the right of point b, and point b is to the right of the origin O, the mobile chassis 8 stops moving and is at position D. The wheel hub motor encoder of the mobile chassis 8 records the moving distance of CD. Turn off the large field of view line structured light sensor 6, and the mobile chassis 8 is in a stationary state. Trigger the large field of view line structured light sensor 6 once and record the distance of point b to the line segment ob in the large field of view line structured light sensor 6. As shown in Figure 11 (1), the width dimension ab=ao+CD+ob of the large box steel structure 1 can be obtained. The model of the large box steel structure 1 can be confirmed based on the width dimension. Finally, control the mobile chassis 8 along The direction is a straight line movement from position D to position E, which is at the midpoint of line segment ab.

[0096] It is easy to know that, corresponding to the first movement control step, points a and b are the first end point and the second end point of the transverse straight line, respectively, and the first direction is direction, the second direction is Direction. It should be noted that Figure 11(1)-Figure 11(4) The definitions of endpoints and moving directions are similar and will not be repeated below.

[0097] (2) Corresponding to the second movement control step, if the position C of the mobile chassis 8 is at the ae side, point c is on the left side of point a, point a is on the right side of the origin O, and point d is on the right side of the origin a. As shown in Figure 11 (2), according to the steps in the seventh step (1), the width dimension ab of the large box steel structure 1 can be obtained by the same logic. Determine the model of the large box steel structure 1 based on the width dimension. Finally, control the mobile chassis 8 along The direction is a straight line movement from position D to position E, position E is at the midpoint of line segment ab, DE = ab / 2-ob.

[0098] (3) Corresponding to the second movement control step, if the position C of the mobile chassis 8 is at the ae side, point d is on the left side of point a. As shown in FIG11(3), the large field of view line structured light sensor 6 is continuously triggered, and the mobile chassis 8 is controlled to move along When point d in the light cd emitted by the large field of view line structure light sensor 6 is to the right of point a, stop moving the chassis 8. At this time, the state is consistent with Figure 11 (2). According to the steps in step 7 (2), the width dimension ab of the large box steel structure 1 can be obtained by the same logic. According to this width dimension, the model of the large box steel structure 1 can be confirmed. Finally, control the moving chassis 8 along The direction is a straight line movement from position D to position E, position E is at the midpoint of line segment ab, DE = ab / 2-ob.

[0099] (4) Corresponding to the fourth movement control step, if the position C of the mobile chassis 8 is at the ae side, point c is to the right of point a. As shown in FIG11(4), the large field of view line structured light sensor 6 is continuously triggered, and the mobile chassis 8 is controlled to move along When point c in the light cd emitted by the large field of view line structure light sensor 6 is to the left of point a, the chassis 8 stops moving. At this time, the state is consistent with Figure 11 (1). According to the steps in step 7 (1), the width dimension ab = ao + CD + ob of the large box steel structure 1 can be obtained by the same logic. The model of the large box steel structure 1 can be confirmed based on the width dimension. Finally, the chassis 8 is controlled to move along The direction is a straight line movement from position D to position E, position E is at the midpoint of line segment ab, DE = ab / 2-ob.

[0100] (5) The situation where point c and point a, the origin O and point a, and point d and point a just coincide with each other is not considered because the sensor accuracy cannot achieve such an ideal state.

[0101] (6) Relative to Figure 11(1)-Figure 11(4) The endpoint and direction of movement, Figure 12(1)-Figure 12(4) For the opposite direction of movement. That is, Figure 12(1)-Figure 12(4) In the first movement control step, points b and a are the first and second endpoints of the transverse straight line, respectively, and the first direction is direction, the second direction is direction.

[0102] Thus, corresponding to the first movement control step, as shown in FIG12(1), if the position C of the mobile chassis 8 is on the be side, point d is on the right side of point b, and point b is on the right side of the origin O, the large field of view line structured light sensor 6 is turned off, and the mobile chassis 8 is in a stationary state. The large field of view line structured light sensor 6 is triggered once, and the distance of point b to line segment bo in the large field of view line structured light sensor 6 is recorded. The large field of view line structured light sensor 6 is continuously triggered, and the mobile chassis 8 is controlled to move along Direction of linear motion. When point c in the light cd emitted by the large field of view line structured light sensor 6 is to the left of point a, and point a is to the left of the origin O, the mobile chassis 8 stops moving and is at position D. The wheel hub motor encoder of the mobile chassis 8 records the moving distance of CD. Turn off the large field of view line structured light sensor 6, and the mobile chassis 8 is in a stationary state. Trigger the large field of view line structured light sensor 6 once to record the distance of point a from the line segment oa in the large field of view line structured light sensor 6. As shown in Figure 12 (1), the width dimension ab=oa+CD+ob of the large box steel structure 1 can be obtained, and the model of the large box steel structure 1 can be confirmed based on the width dimension. Finally, control the mobile chassis 8 along The direction is a straight line movement from position D to position E, position E is at the midpoint of line segment ab, DE = ab / 2-oa.

[0103] (7) Corresponding to the second movement control step, as shown in Figure 12 (2), if the position C of the mobile chassis 8 is on the be side, point d is on the right side of point b, b is on the left side of the origin O, and c is on the left side of point b. According to the steps in the seventh step (6), the width dimension ab of the large box steel structure 1 can be obtained by the same logic. According to this width dimension, the model of the large box steel structure 1 can be confirmed. Finally, the mobile chassis 8 is controlled to move along The direction is a straight line movement from position D to position E, position E is at the midpoint of line segment ab, DE = ab / 2-oa.

[0104] (8) Corresponding to the third movement control step, as shown in FIG12(3), if the position C of the mobile chassis 8 is at the be side, point c is to the right of point b, the large field of view line structured light sensor 6 is continuously triggered, and the mobile chassis 8 is controlled to move along When point c in the light cd emitted by the large field of view line structure light sensor 6 is to the left of point b, the chassis 8 stops moving. At this time, the state is consistent with Figure 12 (2). According to the steps in step 7 (7), the width dimension ab = CD + oa-ob of the large box steel structure 1 can be obtained. According to the width dimension, the model of the large box steel structure 1 can be confirmed. Finally, the chassis 8 is controlled to move along The direction is a straight line movement from position D to position E, position E is at the midpoint of line segment ab, DE = ab / 2-oa.

[0105] (9) Corresponding to the fourth movement control step, as shown in FIG12(4), if the position C of the mobile chassis 8 is on the be side, point d is on the left side of point b. As shown in FIG12(4), continuously triggering the large field of view line structured light

[0106] Sensor 6, and controls the moving chassis 8 along The chassis 8 moves in a straight line in the direction of the large field of view line structure light sensor 6. When the point d in the light cd emitted by the large field of view line structure light sensor 6 is to the right of the point b, the chassis 8 stops moving. At this time, the state is consistent with Figure 12 (1). According to the steps in the seventh step (6), the width dimension ab = oa + CD + ob of the large box steel structure 1 can be obtained. According to the width dimension, the model of the large box steel structure 1 can be confirmed. Finally, the chassis (8) is controlled to move along The direction is a straight line movement from position D to position E, position E is at the midpoint of line segment ab, DE = ab / 2-oa.

[0107] (10) The situation where point c and point b, the origin O and point b, and point d and point b just coincide with each other is not considered because the sensor accuracy cannot achieve such an ideal state.

[0108] The eighth step S8 is to control the mobile robot to work.

[0109] According to steps 5 and 7, Figure 11(1)-Figure 12(4) As shown, the current posture of the mobile chassis 8 is that the midpoint perpendicular line is perpendicular to the plane where the ab line of the large box steel structure 1 is located, and the midpoint perpendicular line position of the mobile chassis 8 is at the midpoint e of the ab line, and at this time, it has reached the expected target point position B. The large field of view line structured light sensor 6 is triggered once to confirm the distance between the mobile chassis 8 and the large box steel structure 1, and the mobile chassis 8 is adjusted to move forward or backward to the preset position for work.

[0110] Therefore, the example of the embodiment of the present application completes the posture adjustment of the mobile chassis 8 through eight steps, and realizes the model recognition of the large box steel structure 1 and the secondary precise positioning of the vehicle body, solving the problem of being unable to weld according to the preset robot trajectory due to poor navigation accuracy, inaccurate positioning, and workpiece placement offset. Specifically, the example of the embodiment of the present application includes at least the following innovative technical solutions:

[0111] 1. It is proposed to create a virtual tire and solve the actual tire angle synchronously through the virtual tire, so as to realize the path tracking PID closed-loop control of the mobile robot.

[0112] 2. Scan the workpiece surface with line structured light to obtain point cloud data, filter interference point clouds through density clustering and other methods, fit the line through the least squares method to obtain the line point cloud. Then, calculate the angle θ between the body and the horizontal plane of the workpiece, and control the body to rotate around the original angle θ to achieve posture adjustment.

[0113] 3. Use line structured light to continuously scan the surface of the workpiece, and control the mobile robot to move in a straight line along the horizontal direction of the workpiece surface. Use the mutation of point cloud data to confirm that the mobile robot has reached the end position of the workpiece in the horizontal direction. Then, use the robot to statically shoot the point clouds at both ends of the horizontal workpiece to obtain the coordinate position in the sensor, and calculate the encoder distance of the mobile robot. In this way, the distance between the two ends of the horizontal plane of the workpiece can be calculated, and the robot can be controlled to move within the threshold range of the horizontal X-axis of the workpiece. Among them, the mutation of point cloud data can be understood by referring to the above, which mainly refers to the process from nothing to something or from something to nothing of the point cloud. For example, within the field of view of the line structured light, it can be hit on the workpiece to generate a point cloud, or it may not be hit on the workpiece or exceed the field of view, and the point cloud disappears, showing a point cloud mutation phenomenon.

[0114] 4. Scan the workpiece through line structured light to confirm the distance between the workpiece and the mobile robot in the Z-axis direction, and control the position of the mobile robot in the Z-axis direction.

[0115] Therefore, in the application scenario of the mobile welding robot system in this example, the application of the embodiment of the present application can solve the problems of low traditional navigation accuracy and failure to converge the target position; it can realize the model recognition of large box steel structures and the adjustment of the body posture for secondary precise positioning, and solve the problem that the workpiece placement is offset and cannot be welded according to the preset robot trajectory; it can also solve the traditional workpiece identification and positioning solution, which requires pre-modeling of large workpieces, using multiple cameras and multiple positions to shoot the workpieces, screening and splicing a large amount of workpiece point cloud data, and then aligning it with the model point cloud, resulting in high cost investment, large amount of point cloud data, complex algorithm, low stability, and low alignment success rate.

[0116] It should be noted that, in addition to the four-wheel mobile welding robot shown in the above example, the embodiments of the present application can also be applied to two-wheel mobile robots, as well as mobile robots that perform other tasks (such as painting walls, laying bricks, and carrying).

[0117] In addition, the line structured light sensor in the above example does not limit the line structured light type, and other sensors that can obtain the point cloud coordinate (x, z) values ​​of a straight line or a plane point cloud can be used as a substitute and should all fall within the protection scope of the embodiments of the present application.

[0118] In summary, through the above examples, back to Figure 1 The motion positioning control method of the mobile robot in the embodiment of the present application essentially provides a solution of "coarse positioning of the target point position + robot posture adjustment + precise positioning of the target point position", which can be specifically described as:

[0119] First, create a virtual tire for the mobile chassis, use three-dimensional visual sensors such as lidar sensors to scan the environment, plan the path and simultaneously solve the Ackerman chassis tire steering angle, and use PID closed-loop control to track the mobile robot path to achieve coarse positioning of the target point.

[0120] Second, at the rough positioning position, the workpiece surface is scanned using line structured light, the noise is filtered using the point cloud algorithm, and the straight line vector of the point cloud on the workpiece surface is obtained by fitting the straight line using the least squares method. The angle θ between the X-axis vector of the line structured light coordinate axis and the straight line vector, that is, the body rotation attitude angle, is solved to achieve body attitude adjustment.

[0121] Third, after completing the body posture adjustment, use line structured light to continuously scan the workpiece surface, and control the mobile chassis to make horizontal linear motion along the horizontal direction of the workpiece surface. Through the mutation of point cloud data, determine whether the mobile chassis has reached the end position of the workpiece and stop moving at the end position. Static scan the point cloud at both ends of the workpiece, obtain the coordinate points of the two ends of the workpiece in the sensor, and synchronously record the distance traveled by the mobile chassis when moving to both ends, comprehensively calculate the distance size at both ends of the workpiece, and match the workpiece model in the process library. In addition, obtain the relative position relationship between the mobile chassis and the workpiece in the X-axis and Z-axis coordinate systems, control the robot to move to the preset target point position, and realize the secondary precise positioning of the mobile chassis.

[0122] Furthermore, based on the solution of “coarse positioning of target point position + robot posture adjustment + precise positioning of target point position”, the embodiment of the present application has at least the following advantages:

[0123] First, the embodiment of the present application proposes a solution for implementing PID closed-loop control of the navigation path based on a virtual tire path tracking control strategy, which solves the problems of low accuracy of traditional navigation and failure to converge the target position.

[0124] Second, the embodiment of the present application proposes a solution for large workpiece model recognition based on visual sensors, and a corresponding set of mobile robot motion secondary precision positioning control strategies can be developed, which can realize the model recognition of the target workpiece and perform secondary precision positioning based on the body posture adjustment, solving the problem of being unable to work according to the preset robot trajectory due to poor navigation accuracy, inaccurate positioning, and workpiece placement offset.

[0125] Third, compared with the traditional workpiece identification and positioning solution, the embodiment of the present application does not need to model large workpieces in advance, nor does it need to use multiple cameras and multiple camera positions to shoot the workpieces to screen, splice and align the model point cloud data of a large amount of workpieces. Compared with the traditional workpiece identification and positioning solution with high cost investment, large amount of point cloud data, complex algorithm, low stability, low registration success rate and other problems, the embodiment of the present application has low cost, small amount of point cloud data, simple algorithm, high stability and high registration success rate.

[0126] Fig.13 The structure block diagram of a motion positioning control device for a mobile robot according to an embodiment of the present application is schematically shown. Fig.13 As shown, the motion positioning control device may include: a memory configured to store instructions; and a processor configured to call instructions from the memory and implement the above-mentioned motion positioning control method of the mobile robot when executing the instructions.

[0127] The motion positioning control device may be a controller integrated on the mobile robot or a remote controller.

[0128] For more implementation details and effects of the motion positioning control device, reference may be made to the motion positioning control method for a mobile robot in the above-mentioned embodiment, which will not be described in detail here.

[0129] Fig.14 A structural block diagram of a motion positioning control system for a mobile robot according to an embodiment of the present application is schematically shown, the system comprising: a sensor component 100, the sensor component 100 comprising at least a line structured light sensor mounted on the mobile robot, for emitting line structured light to scan the surface of the target workpiece to obtain corresponding point cloud data; and the above-mentioned motion positioning control device 200, for controlling the mobile robot to move to a target point position according to the point cloud data.

[0130] The motion positioning control system is, for example, Figure 2 A mobile welding robot system, wherein the sensor component 100 includes, for example, a weld tracking sensor 3, a multi-line laser radar sensor 5, a large field of view line structured light sensor 6 and an ultrasonic sensor 7. The motion positioning control device 200, for example, adopts a vehicle controller (VCU) of a mobile chassis 8, and may also adopt a remote controller. The operating components on the mobile robot include, for example, a welding robot arm and a welding gun 4, a welding machine and a welding system 9, etc. In addition, the motion positioning control system may also include power components such as a rope winding mechanism 10, a power supply line 11 and a power supply column 12.

[0131] The present application also provides a mobile robot, including any of the above-mentioned mobile robot motion positioning control systems. Figure 2 The mobile welding robot shown can also be a mobile robot that performs tasks such as wall painting, brick laying, and transportation.

[0132] An embodiment of the present application also provides a machine-readable storage medium, on which instructions are stored, and the instructions are used to enable a machine to execute the motion positioning control method of the mobile robot of the above embodiment.

[0133] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0134] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0135] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0136] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0137] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0138] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0139] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0140] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0141] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A motion positioning control method for a mobile robot, characterized in that: include: When the mobile robot reaches the target point position within a deviation threshold range, adjusting the posture of the mobile robot according to point cloud data obtained by the mobile robot emitting line structured light to the target workpiece, so that the emitted line structured light is aligned with the target workpiece; as well as After the posture adjustment, the mobile robot is controlled to move in a straight line parallel to the target workpiece and continuously emit line structured light, and according to the position change of the continuously emitted line structured light relative to the target workpiece, the lateral position of the mobile robot relative to the target workpiece is adjusted so that the mobile robot reaches the target point position.

2. The motion positioning control method according to claim 1, characterized in that: The deviation threshold range is determined so that when the target workpiece is placed within the specified threshold area, it is within the field of view corresponding to the line structured light.

3. The motion positioning control method according to claim 1, characterized in that: In the process of the mobile robot reaching the target point position within the deviation threshold range, the motion positioning control method further includes: Determining a proposed turning angle of a virtual wheel according to a deviation factor between an actual path of the mobile robot and a planned path, wherein the virtual wheel is located in the middle of a pair of actual walking wheels of the mobile robot; Determining the rotation angle of the actual walking wheel of the mobile robot according to the determined rotation angle of the virtual wheel; and According to the actual turning angle of the walking wheel, path tracking is performed to control the mobile robot to reach the deviation threshold range of the target point position.

4. The motion positioning control method according to claim 1, characterized in that: The posture adjustment of the mobile robot comprises: Performing straight line fitting on the point cloud data, and selecting a first straight line from the fitted straight lines; The first straight line is translated along the Z axis of the line structured light plane coordinate system to obtain a second straight line intersecting the X axis of the line structured light plane coordinate system, wherein the optical axis corresponding to the line structured light is the Z axis, and the axis perpendicular to the Z axis is the X axis; Acquire the angle between the second straight line and the X-axis of the line structured light plane coordinate system as the body rotation angle; and The mobile robot is controlled to rotate the body rotation angle in situ around the body axis to complete the posture adjustment.

5. The motion positioning control method according to claim 1, characterized in that: The adjusting the lateral position of the mobile robot relative to the target workpiece comprises: determining a transverse straight line where the line structured light plane intersects the outer surface of the target workpiece; and According to the current position of the mobile robot and the position change of the current line structure light relative to the transverse straight line, the mobile robot is controlled to move along the direction of the transverse straight line so that the mobile robot reaches the target point position.

6. The motion positioning control method according to claim 5, characterized in that: The motion positioning control method also includes: Determine the length of the transverse straight line as the width of the target workpiece according to the moving distance of the mobile robot along the direction of the transverse straight line and the distance between the endpoint of the transverse straight line and the optical axis point of the current line structured light on the transverse straight line; and The model of the target workpiece is determined according to the width of the target workpiece.

7. The motion positioning control method according to claim 5, characterized in that: The controlling the mobile robot to move along the direction of the transverse straight line comprises: a first movement control step, in which, when the line structured light emitted by the mobile robot at the current position after the posture adjustment covers the first end point of the transverse straight line but cannot cover the second end point of the transverse straight line, the mobile robot is controlled to move along a first direction until the corresponding line structured light covers the second end point of the transverse straight line, and the mobile robot is controlled to stop, wherein the first direction is the direction from the first end point to the second end point, and the second direction is opposite to the first direction; and The second movement control step controls the mobile robot to turn and move in the second direction until the optical axis point of the corresponding line structured light coincides with the midpoint of the transverse straight line, and then controls the mobile robot to stop, wherein the position of the mobile robot when the coincidence occurs is the target point position.

8. The motion positioning control method according to claim 7, characterized in that: The controlling the mobile robot to move along the direction of the transverse straight line further comprises: a third movement control step, in which, when the line structured light emitted by the mobile robot at the current position after the posture adjustment cannot cover any endpoint of the transverse straight line and does not generate point cloud data, the mobile robot is controlled to move along the first direction until the corresponding line structured light covers the first endpoint, and the first movement control step is started; and The fourth movement control step is to control the mobile robot to move along the second direction when the line structured light emitted by the current position of the mobile robot after the posture adjustment cannot cover any endpoint of the transverse straight line and can generate point cloud data, until the corresponding line structured light covers the first endpoint, and then start to execute the first movement control step.

9. A motion positioning control device for a mobile robot, characterized in that: include: a memory configured to store instructions; as well as A processor is configured to call the instructions from the memory and implement the motion positioning control method according to any one of claims 1 to 8 when executing the instructions.

10. A motion positioning control system for a mobile robot, characterized in that: include: A sensor component, the sensor component at least comprising a line structured light sensor mounted on the mobile robot, for emitting line structured light to scan the surface of a target workpiece to obtain corresponding point cloud data; as well as The motion positioning control device described in claim 9 is used to control the mobile robot to move to a target point position based on the point cloud data.

11. The motion positioning control system according to claim 10, characterized in that: The sensing component also includes a multi-line laser radar sensor and / or an ultrasonic sensor installed on the mobile robot, wherein the multi-line laser radar sensor is used to assist the mobile robot in path planning, obstacle avoidance or positioning, and the ultrasonic sensor is used to assist the mobile robot in obstacle avoidance.

12. A mobile robot, characterized in that: Includes the motion positioning control system according to claim 10 or 11.

13. A machine-readable storage medium, characterized in that: The machine-readable storage medium stores instructions, which are used to enable a machine to execute the motion positioning control method according to any one of claims 1 to 8.

Images