AGV double-magnetic-conductance control method and system, AGV, equipment and medium

Abstract

The invention discloses a double-magnetic-conductance control method and system of an AGV, the AGV, equipment and a medium, the centers of two magnetic sensors are used as control target points, forward kinematics equations of each wheel and the control target points are constructed, the current speed of a vehicle body and the current speed deflection angles of the two control target points are obtained through inverse kinematics solution, and the control target points of the AGV are obtained. And calculating a predicted deviation correction angle of each control target point by combining a track deviation measurement result of the magnetic sensor, and finally performing forward kinematics solution to obtain a target speed and a target speed deflection angle of each wheel. According to the method, the positions of the two magnetic sensors serve as control targets, a front control point and a rear control point can be well considered by adopting a double-control-target-point angle deviation correction mode, rapid deviation correction of the AGV can be achieved, the deviation correction response speed is greatly increased, the method can be suitable for complex and variable paths, various variable paths can be well followed, and the method is suitable for large-scale popularization and application. And the path following precision is improved, and the control error is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of AGV navigation control, and in particular, to a dual magnetic guide control method and system of an AGV, an AGV, an electronic device, and a computer-readable storage medium. Background Art

[0002] As an automatic mobile vehicle, AGV is widely used in logistics, manufacturing, warehousing, medical and other industries, and occupies an important position in the industrial field. Accurate motion navigation is the prerequisite for completing narrow space movement and precise delivery, so the navigation control method of AGV is particularly important. At present, the commonly used navigation methods can be divided into laser navigation, visual navigation, IMU+GPS navigation, track navigation, magnetic navigation and other methods according to the type of sensor. Among them, laser navigation or visual navigation relies on laser radar or camera to obtain surrounding environment information, and matches with existing maps for absolute positioning, so as to perform posture control. This navigation method is technically complex and requires obvious environmental characteristics. When the environment changes, the map needs to be updated, and the navigation reliability is not high. IMU+GPS navigation is suitable for outdoor navigation. Track navigation requires pre-laying of tracks and cannot change the path. Magnetic navigation performs motion correction according to the deviation between the magnetic sensor and the magnetic stripe. The control is simple and reliable, and the laying and maintenance costs of the magnetic stripe are low, and the scalability is strong, so it is widely used.

[0003] At present, most AGV magnetic sensor layouts adopt a central layout, that is, the sensor is placed at the geometric center of the vehicle to control and correct the center position. However, the central layout method has a large control error for larger vehicles. Therefore, for long AGVs, a front and rear dual magnetic guide arrangement is usually adopted to control the vehicle posture and position at the same time. However, the current dual magnetic guide control method still transfers the errors measured by the two magnetic sensors to a control center, which cannot take into account the front and rear control points. It is difficult to apply to complex and changeable paths, has a slow response speed, and has poor accuracy in motion response. Summary of the invention

[0004] The present invention provides a dual magnetic guide control method and system for an AGV, an AGV, an electronic device, and a computer-readable storage medium, which can realize rapid deviation correction of the AGV, greatly improve the deviation correction response speed, and can be applicable to complex and changeable paths, can follow various changing paths well, and also improve the path following accuracy, greatly reducing the control error.

[0005] According to one aspect of the present invention, a dual magnetic guide control method for an AGV is provided, wherein two magnetic sensors are respectively arranged at the front and rear edges of the vehicle body and parallel to the forward direction of the vehicle body, and the method includes the following contents:

[0006] A rectangular coordinate system is established with the center of the magnetic sensor as the origin, the forward direction as the X direction, and the left direction as the Y direction. The centers of the two magnetic sensors are used as the two control target points to construct the forward kinematic equations of each wheel and the two control target points.

[0007] The current speed and current speed angle of each wheel are collected, and the inverse kinematics is solved in combination with the forward kinematics equation to calculate the current speed of the vehicle and the current speed angles of the two control target points;

[0008] Based on the current speed of the vehicle, the current speed deviation angle of each control target point and the trajectory deviation measurement result of the corresponding magnetic sensor, the predicted deviation correction angle of each control target point is calculated respectively;

[0009] The target speed of the vehicle is input, and the predicted correction angles of the two control target points and the forward kinematics equation are combined to perform forward kinematics solution to calculate the target speed and target speed deviation angle of each wheel.

[0010] Furthermore, the forward kinematics equation is:

[0011]

[0012] in, and Respectively represent the current speed of the i-th wheel in the x direction and in the y direction, θ i represents the current speed deviation angle of the i-th wheel, v represents the current speed of the vehicle, α1 and α2 represent the current speed deviation angles of the rear control target point and the front control target point respectively, and x i and i represents the coordinate value of the center of the i-th wheel, and d represents the distance between the two control target points.

[0013] Furthermore, for the motion trajectory with small curvature change, the predicted correction angle of each control target point is calculated based on the following formula:

[0014]

[0015] Where v represents the current speed of the vehicle, S i+1 and S i They represent the error values ​​caused by path changes at time (i+1) and time i, respectively, and e i represents the trajectory deviation measurement value of the magnetic sensor corresponding to the control target point at time i, L represents the system characteristic constant, Δt represents the time interval between two adjacent moments, ΔH i+1 and ΔH i They represent the longitudinal movement distance of the control target point at time (i+1) and time i, respectively. i Indicates the current velocity deviation angle of the control target point at time i, α i+1Represents the predicted correction angle at time (i+1).

[0016] Furthermore, for the motion trajectory with large curvature change, the predicted correction angle of each control target point is calculated based on the following formula:

[0017] S i+1 =e -vΔt S i +e i

[0018] ΔH i+1 =e -vΔt ΔH i +vΔttanα i ;

[0019]

[0020] Where v represents the current speed of the vehicle, S i+1 and S i They represent the error values ​​caused by path changes at time (i+1) and time i, respectively, and e i represents the trajectory deviation measurement value of the magnetic sensor corresponding to the control target point at time i, L represents the system characteristic constant, Δt represents the time interval between two adjacent moments, ΔH i+1 and ΔH i They represent the longitudinal movement distance of the control target point at time (i+1) and time i, respectively. i Indicates the current velocity deviation angle of the control target point at time i, α i+1 Represents the predicted correction angle at time (i+1).

[0021] Furthermore, after the predicted correction angle of each control target point is calculated, the following contents are also included:

[0022] Based on the current speed of the vehicle body and the trajectory deviation measurement results of the magnetic sensor corresponding to each control target point, the compensation angle of each control target point is calculated, and the predicted correction angle of each control target point is compensated accordingly using the compensation angle.

[0023] Furthermore, the compensation angle of each control target point is calculated based on the following formula:

[0024] Δθ i+1 =k p (e i -e i-1 )+k i e i +k d (e i -2e i-1 +e i-2 )

[0025] Δα i+1 =Δα i +Δθ i+1 ;

[0026] k i =vΔt / l i

[0027] k d = l d / (vΔt);

[0028] Among them, Δα i+1 and Δα i They represent the compensation angles of the control target point at time (i+1) and time i, Δθ i+1 represents the incremental PID compensation angle of the control target point at time (i+1), e i 、e i-1 and e i-2 They represent the trajectory deviation measurement values ​​of the control target point at time i, (i-1) and (i-2), respectively, and k p Represents the proportional constant, taking a constant value, k i and k d They represent the integral constant and the differential constant respectively, v represents the current speed of the vehicle, Δt represents the time interval between two adjacent moments, l i and l d represent the integral coefficient and the differential coefficient respectively.

[0029] In addition, the present invention also provides a dual magnetic guide control system for an AGV, which adopts the dual magnetic guide control method as described above, and includes:

[0030] A forward kinematics equation construction module is used to establish a rectangular coordinate system with the center of the rear magnetic sensor as the origin, the forward direction as the X direction, and the left direction as the Y direction, and to construct the forward kinematics equations of each wheel and the two control target points with the centers of the two magnetic sensors as the two control target points;

[0031] The inverse kinematics solution module is used to collect the current speed and current speed deviation angle of each wheel, and perform inverse kinematics solution in combination with the forward kinematics equation to calculate the current speed of the vehicle body and the current speed deviation angles of the two control target points;

[0032] A correction angle prediction module is used to calculate the predicted correction angle of each control target point based on the current speed of the vehicle body, the current speed deviation angle of each control target point and the trajectory deviation measurement result of the corresponding magnetic sensor;

[0033] The forward kinematics solution module is used to input the target speed of the vehicle body, and perform forward kinematics solution in combination with the predicted correction angles of the two control target points and the forward kinematics equation to calculate the target speed and target speed deviation angle of each wheel.

[0034] In addition, the present invention also provides an AGV, which adopts the dual magnetic guide control system as described above.

[0035] In addition, the present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the above method by calling the computer program stored in the memory.

[0036] In addition, the present invention also provides a computer-readable storage medium for storing a computer program for performing dual magnetic guide control on an AGV, wherein the computer program executes the steps of the method described above when running on a computer.

[0037] The present invention has the following beneficial effects:

[0038] The dual magnetic guide control method of the AGV of the present invention uses the centers of the front and rear magnetic sensors as the two control target points, and constructs the forward kinematics equations of each wheel and the two control target points, and then obtains the current speed of the vehicle body and the current speed deviation angle of the two control target points through inverse kinematics solution, and then calculates the predicted correction angle of each control target point based on the inverse kinematics solution result and the trajectory deviation measurement result of the magnetic sensor, and finally, performs forward kinematics solution in combination with the target vehicle speed of the vehicle body, thereby calculating the target speed and target speed deviation angle of each wheel. This method uses the positions of both magnetic sensors as control targets, and the dual control target point angle correction method can well take into account the front and rear control points, which can not only realize the rapid correction of AGV and greatly improve the correction response speed, but also can be applied to complex and changeable paths, can well follow various changing paths, and also improves the path following accuracy, greatly reducing the control error.

[0039] In addition, the dual magnetic guide control system and AGV of the present invention also have the above advantages.

[0040] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0042] Figure 1It is a flow chart of the dual magnetic guide control method of the AGV according to the preferred embodiment of the present application;

[0043] Figure 2 is a schematic diagram of the arrangement of magnetic sensors on the AGV in a preferred embodiment of the present application;

[0044] Figure 3 It is a schematic diagram of the principle of calculating the predicted correction angle in the preferred embodiment of the present application;

[0045] Figure 4 It is another flow chart of the dual magnetic guide control method of the AGV of the preferred embodiment of the present application;

[0046] Figure 5 It is a schematic diagram of the overall control strategy of the dual magnetic guide control method of the preferred embodiment of the present application;

[0047] Figure 6 It is a schematic diagram of simulation results of control simulation using a dual magnetic permeability control method in a preferred embodiment of the present application;

[0048] Figure 7 It is a schematic diagram of the module structure of a dual magnetic guide control system of an AGV according to another embodiment of the present application.

[0049] Description of Reference Numerals

[0050] 1. Front magnetic sensor; 2. Rear magnetic sensor; 3. Motion path magnetic stripe. DETAILED DESCRIPTION

[0051] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0052] Reference Figure 1 The preferred embodiment of the present application provides a dual magnetic guide control method for an AGV, wherein two magnetic sensors are respectively arranged at the front and rear edges of the vehicle body and parallel to the forward direction of the vehicle body, and includes the following contents:

[0053] Step S1: Establish a rectangular coordinate system with the center of the magnetic sensor as the origin, the forward direction as the X direction, and the left direction as the Y direction, and use the centers of the two magnetic sensors as the two control target points to construct the forward kinematic equations of each wheel and the two control target points;

[0054] Step S2: collecting the current speed and current speed deflection angle of each wheel, and solving the inverse kinematics in combination with the forward kinematics equation to calculate the current speed of the vehicle body and the current speed deflection angles of the two control target points;

[0055] Step S3: Based on the current speed of the vehicle body, the current speed deviation angle of each control target point and the trajectory deviation measurement result of the corresponding magnetic sensor, the predicted deviation correction angle of each control target point is calculated respectively;

[0056] Step S4: input the target speed of the vehicle body, and perform forward kinematics solution in combination with the predicted deviation correction angles of the two control target points and the forward kinematics equation to calculate the target speed and target speed deviation angle of each wheel.

[0057] It can be understood that the dual magnetic guide control method of the AGV of this embodiment uses the centers of the front and rear magnetic sensors as the two control target points, and constructs the forward kinematic equations of each wheel and the two control target points, and then obtains the current speed of the vehicle body and the current speed deviation angle of the two control target points through inverse kinematics solution, and then calculates the predicted correction angle of each control target point based on the inverse kinematics solution result and the trajectory deviation measurement result of the magnetic sensor, and finally, performs forward kinematics solution in combination with the target vehicle speed of the vehicle body, thereby calculating the target speed and target speed deviation angle of each wheel. This method uses the positions of both magnetic sensors as control targets, and the dual control target point angle correction method can well take into account the front and rear control points, which can not only realize the rapid correction of AGV and greatly improve the correction response speed, but also can be applied to complex and changeable paths, can well follow various changing paths, and also improves the path following accuracy, greatly reducing the control error.

[0058] It is understandable that Figure 2 As shown, the front magnetic sensor 1 is arranged at the front edge of the vehicle body, and the rear magnetic sensor 2 is arranged at the rear edge of the vehicle body. The AGV needs to be driven to travel on the moving path magnetic strip 3. In step S1, a rectangular coordinate system 0XY is established with the center of the rear magnetic sensor 2 as the origin, the forward direction as the X direction, and the left direction as the Y direction. The coordinates of each wheel can be measured by the total station as (x i ,y i ), the coordinates of the front magnetic sensor are (d, 0). Kinematic analysis of the AGV shows that the instantaneous movement of the AGV can be regarded as all points rotating around the center of the circle. A vertical line perpendicular to the wheel speed is drawn through the center of all wheels. The intersection of each vertical line is the center of the circle O'. A vertical line O'H is drawn between the center of the circle and the line OF connecting the two magnetic sensors. According to the geometric relationship, it can be obtained that: O'H tanα1+O'H tan(-α2)=d, α1 and α2 represent the current speed deviation angles of the rear control target point and the front control target point respectively, and d represents the distance between the two magnetic sensors. Therefore, the y coordinate value O'H of the center of the circle O' can be obtained as: The x-coordinate value of the center O' is: Therefore, by solving the right triangle, we can get the coordinates of the center O': The turning radius r of each wheel center point can be obtained by the two-point distance formulai , taking point H as the reference object, the angular velocity of the vehicle is:

[0059] Since v = ωr, the forward kinematic equations of each wheel and the control target point can be constructed as follows:

[0060]

[0061] in, and Respectively represent the current speed of the i-th wheel in the x direction and in the y direction, θ i represents the current speed deviation angle of the i-th wheel, v represents the current speed of the vehicle, α1 and α2 represent the current speed deviation angles of the rear control target point and the front control target point respectively, and x i and i represents the coordinate value of the center of the i-th wheel, and d represents the distance between the two control target points.

[0062] Transforming the angle formula in the forward kinematics equation yields:

[0063] tanθ i (dy i (tanα1-tanα2))=dtanα1-x(tanα1-tanα2);

[0064] Rewriting the above equation into matrix form, it can be expressed as:

[0065]

[0066] It can be understood that in step S2, the current speed v of each wheel can be obtained through each wheel controller. i =[v ix ,v iy ], the current speed deviation angle θ of each wheel can be obtained through each wheel encoder i , and the coordinates of the center points of each wheel (x i ,y i ) is known, so by combining the above angle equations of at least two wheels, the linear least squares method is used to solve the angle equations for inverse kinematics, and the current speed deviation angles α1 and α2 of the two control target points can be obtained. Then, the kinematic constraints of all wheels are added, and the current movement speed v of the vehicle body can be obtained by the linear least squares method.

[0067] It can be understood that in step S3, Figure 3 As shown, assuming that the current velocity deviation angle of the target point at time i is α i , the corresponding track deviation measurement value of the magnetic sensor is e i, driving in the current direction of motion, after a time interval Δt, the predicted value of the trajectory deviation of the magnetic sensor at time i+1 is e i+1 , the horizontal and vertical moving distances are Δd respectively i+1 With ΔH i+1 , then the following relationship exists: i+1 =s i+1 +ΔH i+1 =s i+1 +vΔttanα i , where s i+1 represents the error value caused by the path change at time (i+1), and v represents the current speed of the vehicle. The predicted correction angle can be calculated based on the following formula:

[0068]

[0069] Among them, α i+1 Represents the predicted correction angle at time (i+1).

[0070] It can be seen that the predicted correction angle is determined by two parts. The first part is S i+1 , which is the error caused by path change, and the second part is ΔH i+1 , that is, the error in the direction of motion. Considering that AGV usually adopts a speed following algorithm and the system sampling time interval is stable, all Δt, the system characteristic speed is defined as v o , the time interval is Δt o , so the system characteristic constant L=v o Δt o .Depend on Figure 3 It can be seen that for the motion trajectory with small curvature change, S i+1 ≈e i , and the trajectory and speed change smoothly within the time interval, so the two parts of the error can be re-estimated based on the low-pass filtering algorithm to obtain: Therefore, for a motion trajectory with a small curvature change, the predicted correction angle of each control target point is calculated based on the following formula:

[0071]

[0072] Where v represents the current speed of the vehicle, S i+1 and S i They represent the error values ​​caused by path changes at time (i+1) and time i, respectively, and e i represents the trajectory deviation measurement value of the magnetic sensor corresponding to the control target point at time i, L represents the system characteristic constant, Δt represents the time interval between two adjacent moments, ΔH i+1 and ΔH iThey represent the longitudinal movement distance of the control target point at time (i+1) and time i, respectively. i Indicates the current velocity deviation angle of the control target point at time i, α i+1 Represents the predicted correction angle at time (i+1).

[0073] In addition, the inventors of the present application found in actual applications that the linear function 1-vΔt / L is difficult to respond to motion trajectories with large curvature changes. Therefore, in order to improve the adaptability and accuracy of the algorithm, for motion trajectories with large curvature changes, an exponential function e with the same threshold and change trend is used. -vΔt Instead of a linear function, the predicted correction angle of each control target point is calculated based on the following formula:

[0074] S i+1 =e -vΔt S i +e i

[0075] ΔH i+1 =e -vΔt ΔH i +vΔttanα i ;

[0076]

[0077] Where v represents the current speed of the vehicle, S i+1 and S i They represent the error values ​​caused by path changes at time (i+1) and time i, respectively, and e i represents the trajectory deviation measurement value of the magnetic sensor corresponding to the control target point at time i, L represents the system characteristic constant, Δt represents the time interval between two adjacent moments, ΔH i+1 and ΔH i They represent the longitudinal movement distance of the control target point at time (i+1) and time i, respectively. i Indicates the current velocity deviation angle of the control target point at time i, α i+1 It represents the predicted correction angle at time (i+1). It can be understood that in the present invention, when the curvature change of the motion trajectory is greater than the preset threshold, an exponential function is used to calculate the predicted correction angle, and when the curvature change of the motion trajectory is not greater than the preset threshold, a linear function is used to calculate the predicted correction angle. The specific value of the preset threshold can be set artificially based on experience and is not specifically limited here.

[0078] It can be understood that the present invention can adaptively select different algorithms to calculate the predicted deviation correction angle according to the change in the curvature of the motion trajectory, thereby improving the adaptability of the algorithm and the calculation accuracy of the predicted deviation correction angle.

[0079] It can be understood that in step S4, the target speed v of the vehicle body is input, and combined with the predicted correction angles of the two control target points, it is substituted into the forward kinematics equation for forward kinematics solution to obtain the target speed and target speed deviation angle of each wheel, thereby realizing rapid correction of the AGV, greatly improving the correction response speed, and being applicable to complex and changeable paths, and being able to follow various changing paths well, and also improving the path following accuracy, greatly reducing the control error.

[0080] In addition, if Figure 4 As shown, in another embodiment of the present invention, after calculating the predicted deviation correction angle of each control target point, the dual magnetic guide control method of the AGV further includes the following contents:

[0081] Step S3a: Based on the current speed of the vehicle body and the trajectory deviation measurement result of the magnetic sensor corresponding to each control target point, the compensation angle of each control target point is calculated, and the predicted deviation correction angle of each control target point is compensated accordingly using the compensation angle.

[0082] Specifically, in order to enhance the stability of system control, the present invention also adopts incremental PID compensation to predict the correction angle based on the current speed of the vehicle body and the trajectory deviation measurement results of the magnetic sensor corresponding to each control target point, where the proportional constant k p Take a constant value. Since the system uses the movement distance as the characteristic parameter, the integral constant k i and the differential constant k d They are all related to the movement distance, and the compensation angle of each control target point is calculated based on the following formula:

[0083] Δθ i+1 =k p (e i -e i-1 )+k i e i +k d (e i -2e i-1 +e i-2 )

[0084] Δα i+1 =Δα i +Δθ i+1 ;

[0085] k i =vΔt / l i

[0086] k d = l d / (vΔt);

[0087] Among them, Δα i+1 and Δαi They represent the compensation angles of the control target point at time (i+1) and time i, Δθ i+1 represents the incremental PID compensation angle of the control target point at time (i+1), e i 、e i-1 and e i-2 They represent the trajectory deviation measurement values ​​of the control target point at time i, (i-1) and (i-2), respectively, and k p Represents the proportional constant, taking a constant value, k i and k d They represent the integral constant and the differential constant respectively, v represents the current speed of the vehicle, Δt represents the time interval between two adjacent moments, l i and l d Respectively represent the integral coefficient and the differential coefficient. After calculating the compensation angle of each control target point, the compensation angle is superimposed on the predicted correction angle to obtain the accurate correction angle of each control target point, and then substituted into step S4 for calculation. It can be understood that the compensation angle calculated by the above formula is conducive to ensuring accurate control of the system under path change conditions, further improving the control accuracy of the AGV.

[0088] It can be understood that, as a preferred embodiment, the overall control strategy of the dual magnetic guide control method of the AGV of the present invention is as follows: Figure 5 As shown in the figure, after the wheel moves, the front and rear trajectory deviation values ​​e1 and e2 are measured by two magnetic sensors, and the inverse kinematics estimation is performed according to the current speed and current speed deviation angle of each wheel to obtain the current speed deviation angles α1 and α2 of the two control target points at the current moment, and then the predicted correction angles β1 and β2 of the two control target points are calculated according to the predicted correction angle calculation formula (i.e., the α i+1 ), and in order to enhance the stability of the system, e1 and e2 are input into the incremental PID to obtain the compensation angles Δα1 and Δα2 of the two control target points, and the compensation angles are superimposed with the corresponding predicted correction angles to obtain the accurate correction angles at the next moment, and then the target speed and target speed deviation angle of each wheel are obtained by forward kinematics calculation, and finally, the target speed and target speed deviation angle of each wheel are transmitted to the controller of each wheel to realize the AGV correction control. Among them, the results of the control simulation of the present invention are as follows: Figure 6 As shown, the red line segment represents the connection line between the front and rear two control target points. From the simulation results, it can be seen that even on the curved trajectory, the deviation distance between the front and rear two control target points and the trajectory can still be guaranteed to be very small, and the navigation control accuracy of the AGV is very high.

[0089] In addition, if Figure 7 As shown, another embodiment of the present invention further provides a dual magnetic guide control system for an AGV, preferably using the dual magnetic guide control method as described above, including:

[0090] A forward kinematics equation construction module is used to establish a rectangular coordinate system with the center of the rear magnetic sensor as the origin, the forward direction as the X direction, and the left direction as the Y direction, and to construct the forward kinematics equations of each wheel and the two control target points with the centers of the two magnetic sensors as the two control target points;

[0091] The inverse kinematics solution module is used to collect the current speed and current speed deviation angle of each wheel, and perform inverse kinematics solution in combination with the forward kinematics equation to calculate the current speed of the vehicle body and the current speed deviation angles of the two control target points;

[0092] A correction angle prediction module is used to calculate the predicted correction angle of each control target point based on the current speed of the vehicle body, the current speed deviation angle of each control target point and the trajectory deviation measurement result of the corresponding magnetic sensor;

[0093] The forward kinematics solution module is used to input the target speed of the vehicle body, and perform forward kinematics solution in combination with the predicted correction angles of the two control target points and the forward kinematics equation to calculate the target speed and target speed deviation angle of each wheel.

[0094] It can be understood that the dual magnetic guide control system of the AGV of this embodiment uses the centers of the front and rear magnetic sensors as the two control target points, and constructs the forward kinematics equations of each wheel and the two control target points, and then obtains the current speed of the vehicle body and the current speed deviation angle of the two control target points through inverse kinematics solution, and then calculates the predicted correction angle of each control target point based on the inverse kinematics solution result and the trajectory deviation measurement result of the magnetic sensor, and finally, combines the target speed of the vehicle body to perform forward kinematics solution, so as to calculate the target speed and target speed deviation angle of each wheel. The system uses the positions of both magnetic sensors as control targets, and the dual control target point angle correction method can well take into account the front and rear control points, which can not only realize the rapid correction of AGV and greatly improve the correction response speed, but also can be applied to complex and changeable paths, can well follow various changing paths, and also improve the path following accuracy, greatly reducing the control error.

[0095] In addition, the dual magnetic control system of the AGV also includes:

[0096] The correction angle compensation module is used to calculate the compensation angle of each control target point based on the current speed of the vehicle body and the trajectory deviation measurement result of the magnetic sensor corresponding to each control target point, and use the compensation angle to compensate the predicted correction angle of each control target point accordingly.

[0097] It can be understood that the various modules of the system embodiment correspond to the various steps of the above method embodiment, so the specific working principles of each module are not repeated here, and the corresponding references can be made to the various steps of the above method embodiment.

[0098] In addition, another embodiment of the present invention further provides an AGV, which preferably adopts the dual magnetic guide control system as described above.

[0099] In addition, another embodiment of the present invention further provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the above method by calling the computer program stored in the memory.

[0100] In addition, another embodiment of the present invention further provides a computer-readable storage medium for storing a computer program for performing dual magnetic guide control on an AGV, wherein the computer program executes the steps of the method described above when running on a computer.

[0101] The general form of computer readable storage media includes: floppy disk, flexible disk, hard disk, magnetic tape, any other magnetic medium, CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with a pattern of holes, random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), flash erasable programmable read-only memory (FLASH-EPROM), any other memory chip or cartridge, or any other medium that can be read by a computer. The instructions can further be transmitted or received by a transmission medium. The term transmission medium can include any tangible or intangible medium that can be used to store, encode or carry instructions for execution by a machine, and includes digital or analog communication signals or other intangible media that facilitate the communication of the above instructions. Transmission media include coaxial cables, copper wires and optical fibers, which include the wires of a bus used to transmit a computer data signal.

[0102] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can 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. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0103] 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.

[0104] 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.

[0105] 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 The steps for the functions specified in one or more boxes.

[0106] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0107] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

[0108] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A dual magnetic guide control method for AGV, wherein two magnetic sensors are respectively arranged at the front and rear edges of the vehicle body and parallel to the forward direction of the vehicle body, characterized in that: Includes the following: A rectangular coordinate system is established with the center of the magnetic sensor as the origin, the forward direction as the X direction, and the left direction as the Y direction. The centers of the two magnetic sensors are used as the two control target points to construct the forward kinematic equations of each wheel and the two control target points. The current speed and current speed angle of each wheel are collected, and the inverse kinematics is solved in combination with the forward kinematics equation to calculate the current speed of the vehicle and the current speed angles of the two control target points; Based on the current speed of the vehicle, the current speed deviation angle of each control target point and the trajectory deviation measurement result of the corresponding magnetic sensor, the predicted deviation correction angle of each control target point is calculated respectively; The target speed of the vehicle is input, and the predicted correction angles of the two control target points and the forward kinematics equation are combined to perform forward kinematics solution to calculate the target speed and target speed deviation angle of each wheel.

2. The dual magnetic permeability control method of AGV according to claim 1, characterized in that: The forward kinematic equation is: in, and Respectively represent the current speed of the i-th wheel in the x direction and in the y direction, θ i represents the current speed deviation angle of the i-th wheel, v represents the current speed of the vehicle, α1 and α2 represent the current speed deviation angles of the rear control target point and the front control target point respectively, and x i and i represents the coordinate value of the center of the i-th wheel, and d represents the distance between the two control target points.

3. The dual magnetic permeability control method of AGV according to claim 1, characterized in that: For motion trajectories with small curvature changes, the predicted correction angle of each control target point is calculated based on the following formula: Where v represents the current speed of the vehicle, S i+1 and S i They represent the error values ​​caused by path changes at time (i+1) and time i, respectively, and e i represents the trajectory deviation measurement value of the magnetic sensor corresponding to the control target point at time i, L represents the system characteristic constant, Δt represents the time interval between two adjacent moments, ΔH i+1 and ΔH i They represent the longitudinal movement distance of the control target point at time (i+1) and time i, respectively. i Indicates the current velocity deviation angle of the control target point at time i, α i+1 Represents the predicted correction angle at time (i+1).

4. The dual magnetic permeability control method of AGV according to claim 1, characterized in that: For motion trajectories with large curvature changes, the predicted correction angle of each control target point is calculated based on the following formula: S i+1 =e -vΔt S i +e i ΔH i+1 =e -vΔt ΔH i +vΔttanα i ; Where v represents the current speed of the vehicle, S i+1 and S i They represent the error values ​​caused by path changes at time (i+1) and time i, respectively, and e i represents the trajectory deviation measurement value of the magnetic sensor corresponding to the control target point at time i, L represents the system characteristic constant, Δt represents the time interval between two adjacent moments, ΔH i+1 and ΔH i They represent the longitudinal movement distance of the control target point at time (i+1) and time i, respectively. i Indicates the current velocity deviation angle of the control target point at time i, α i+1 Represents the predicted correction angle at time (i+1).

5. The dual magnetic permeability control method of AGV according to claim 1, characterized in that: After calculating the predicted correction angle of each control target point, the following contents are also included: Based on the current speed of the vehicle body and the trajectory deviation measurement results of the magnetic sensor corresponding to each control target point, the compensation angle of each control target point is calculated, and the predicted correction angle of each control target point is compensated accordingly using the compensation angle.

6. The dual magnetic permeability control method of AGV according to claim 5, characterized in that: The compensation angle of each control target point is calculated based on the following formula: Δθ i+1 =k p (e i -e i-1 )+k i e i +k d (e i -2e i-1 +e i-2 ) Da i+1 =Da i +Δθ i+1 ; k i =vΔt / l i k d =l d / (vΔt); Among them, Δα i+1 and Δα i They represent the compensation angles of the control target point at time (i+1) and time i, Δθ i+1 represents the incremental PID compensation angle of the control target point at time (i+1), e i 、e i-1 and e i-2 They represent the trajectory deviation measurement values ​​of the control target point at time i, (i-1) and (i-2), respectively, and k p Represents the proportional constant, taking a constant value, k i and k d They represent the integral constant and the differential constant respectively, v represents the current speed of the vehicle, Δt represents the time interval between two adjacent moments, l i and l d represent the integral coefficient and the differential coefficient respectively.

7. A dual magnetic guide control system for an AGV, using the dual magnetic guide control method as claimed in any one of claims 1 to 6, characterized in that: include: A forward kinematics equation construction module is used to establish a rectangular coordinate system with the center of the rear magnetic sensor as the origin, the forward direction as the X direction, and the left direction as the Y direction, and to construct the forward kinematics equations of each wheel and the two control target points with the centers of the two magnetic sensors as the two control target points; The inverse kinematics solution module is used to collect the current speed and current speed deviation angle of each wheel, and perform inverse kinematics solution in combination with the forward kinematics equation to calculate the current speed of the vehicle body and the current speed deviation angles of the two control target points; A correction angle prediction module is used to calculate the predicted correction angle of each control target point based on the current speed of the vehicle body, the current speed deviation angle of each control target point and the trajectory deviation measurement result of the corresponding magnetic sensor; The forward kinematics solution module is used to input the target speed of the vehicle body, and perform forward kinematics solution in combination with the predicted correction angles of the two control target points and the forward kinematics equation to calculate the target speed and target speed deviation angle of each wheel.

8. An AGV, characterized in that: The dual magnetic guide control system as claimed in claim 7 is adopted.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the method according to any one of claims 1 to 6 by calling the computer program stored in the memory.

10. A computer-readable storage medium for storing a computer program for dual magnetic guide control of an AGV, characterized in that: When the computer program is run on a computer, the steps of the method according to any one of claims 1 to 6 are executed.

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