AGV turning method with non-axis center as circle center and storage device

Abstract

The application belongs to the technical field of automatic navigation trolley, and particularly relates to an AGV turning method with a non-axis center as a circle center and a storage device, wherein the axis center distance of a first driving unit and a second driving unit of the AGV is L, the midpoint is O, the middle line of a first magnetic track is Y, the middle line of a second magnetic track is X, X is perpendicular to Y and the intersection point is A, and the method comprises the following steps: the AGV travels along the first magnetic track, so that the midpoint O overlaps with the middle line Y; the AGV stops after receiving a turning signal; the distance M between the intersection point A and the midpoint O is obtained, the radius r of a rotating circle, the angle alpha and the angle beta=(180-alpha)*-1 are calculated; the front of the current travel direction of the AGV is 0°, the first driving unit is controlled to rotate the angle alpha, and the second driving unit is controlled to rotate the angle beta; the first driving unit and the second driving unit are driven to move reversely and at a constant speed, and the turning is started, so that the application can improve the adaptability of the AGV to a scene and ensure the accuracy of the turning.

Description

Technical Field

[0001] This invention belongs to the technical field of automated guided vehicles (AGVs), specifically relating to an AGV turning method and storage device that rotates around a non-axial center. Background Technology

[0002] With the development of industrial automation, the application of automated guided vehicles (AGVs) is becoming increasingly widespread. Taking AGVs as an example, they are responsible for various handling tasks in factories, and the application scenarios are becoming more and more complex. For instance, previously, AGVs only needed to travel in one direction along a circular magnetic track to transport goods. However, now, the AGV's travel track has become a track with multiple branches. During the journey, the AGV needs to turn at intersections. The current way for AGVs to turn is mainly achieved through magnetic track navigation. That is, landmark cards are embedded in the magnetic track in advance so that when the AGV travels to a preset position, it can identify that there is an intersection ahead and provide the station allocation information of the intersection (which stations can be reached by turning left, turning right, or going straight). Then, based on the destination station, the AGV determines which direction to travel at the intersection, whether to go straight, turn left, or turn right.

[0003] When a turn at a fork in the road is required, the existing method involves ensuring that the AGV travels to the point where the midpoint between the two drive units intersects with the intersection of the centerlines of two perpendicular magnetic tracks. Then, using this midpoint as the center, the two drive units are controlled to move in opposite directions at the same speed, causing the AGV to rotate in place. When it rotates 90°, it can change direction and continue straight along the other magnetic track. However, in practical applications, the midpoint between the two drive units often does not overlap with the intersection of the centerlines of the two perpendicular magnetic tracks (i.e., there is a deviation between the midpoint and the intersection). In such cases, continuing to use the above control method will result in a deviation, preventing the AGV from properly turning into the other magnetic track. Summary of the Invention

[0004] The purpose of this invention is to overcome the problem that the intersection of the midpoint of the two drive units of the existing magnetic navigation AGV with the center line of the two magnetic tracks does not overlap, which causes deviation when turning. The invention provides an AGV turning method and storage device that rotates with a non-axial center as the center.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A method for turning an AGV that rotates around a non-axial center, wherein the center distance between the axes of the first and second drive units of the AGV is L, the midpoint is O, the centerline of the first magnetic track is Y, the centerline of the second magnetic track is X, X and Y are perpendicular and their intersection point is A, and the method includes the following steps:

[0007] The AGV travels along the first magnetic track, causing the midpoint O to overlap with the center line Y;

[0008] The AGV stops upon receiving a turn signal.

[0009] Obtain the distance M between the intersection point A and the midpoint O, and calculate the radius of the rotation circle. Angle α=arcos(M / r)*(180 / π), angle β=(180-α)*-1;

[0010] With the forward direction of the AGV's current travel direction as 0°, control the rotation angle α of the first drive unit and the rotation angle β of the second drive unit;

[0011] The first drive unit and the second drive unit are driven to move in opposite directions at the same speed, and the turn begins.

[0012] Furthermore, when the landmark card reader on the AGV reads the branch road card, it generates a turning signal.

[0013] Furthermore, the branch road card is pre-set with the coordinate information of the intersection point A, and the distance M is calculated using the coordinate information fed back by the branch road card.

[0014] Furthermore, when turning, the AGV's sensor module detects a signal from the second magnetic track, completing the turn, and the first and second drive units return to center and travel along the second magnetic track.

[0015] The present invention also provides a storage device that stores a plurality of execution instructions, the execution instructions being used to control a module to load and perform the following operations:

[0016] The AGV travels along the first magnetic track, causing the midpoint O to overlap with the center line Y;

[0017] The AGV stops upon receiving a turn signal.

[0018] Obtain the distance M between the intersection point A and the midpoint O, and calculate the radius of the rotation circle. Angle α=arcos(M / r)*(180 / π), angle β=(180-α)*-1;

[0019] With the forward direction of the AGV's current travel direction as 0°, control the rotation angle α of the first drive unit and the rotation angle β of the second drive unit;

[0020] The first drive unit and the second drive unit are driven to move in opposite directions at the same speed, and the turn begins.

[0021] Furthermore, when the landmark card reader on the AGV reads the branch road card, it generates a turning signal.

[0022] Furthermore, the branch road card is pre-set with the coordinate information of the intersection point A, and the distance M is calculated using the coordinate information fed back by the branch road card.

[0023] Furthermore, when the AGV's sensor module detects the signal of the second magnetic track, it completes the turn, and the first and second drive units return to the starting position and travel along the second magnetic track.

[0024] Compared with the prior art, the present invention provides a turning method that can rotate around a non-axial center, thus avoiding the problem of turning deviation caused by the non-overlapping intersection of the midpoints of the two drive units of the AGV and the center lines of the two magnetic tracks, thereby improving the AGV's adaptability to the scene, enhancing its versatility, and ensuring the accuracy of turning. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of an AGV traveling along the first magnetic track.

[0026] Figure 2 This is a schematic diagram of an AGV stopping after receiving a turning signal.

[0027] Figure 3 This is a schematic diagram of the rotation angle of the drive unit of an AGV. Detailed Implementation

[0028] The specific embodiments of the present invention are described below with reference to the accompanying drawings.

[0029] Example 1:

[0030] See Figures 1 to 3 This invention provides a method for an AGV to turn around by rotating around a non-axial center. The AGV is equipped with a first drive unit 1 and a second drive unit 2. In one specific embodiment, the first drive unit 1 and the second drive unit 2 are configured as steering wheels. The center distance between the axes of the two drive units is defined as L, and the midpoint is defined as O. The first magnetic track 3 and the second magnetic track 4 are perpendicular to each other, and their centerlines are defined as Y and X, respectively. The intersection of X and Y is defined as A. The turning method includes the following steps:

[0031] like Figure 1 As shown, the AGV travels along the first magnetic track 3, ensuring that the midpoint O overlaps with the center line Y, and the arrow indicates the direction of the AGV's travel.

[0032] like Figure 2 As shown, the AGV stops after receiving a turning signal. In one specific embodiment, a turn card is configured on the first magnetic track 3. When the landmark card reader on the AGV reads the turn card, a turning signal is generated.

[0033] like Figure 3As shown, the distance M between the intersection point A and the midpoint O is then obtained, and the radius of the rotation circle is calculated. Angle α = arcos(M / r)*(180 / π), angle β = (180-α)*-1; the branch card is preset with the coordinate information of the intersection point A, and the spacing M is calculated by the coordinate information fed back by the branch card. For example, the spacing M can be directly obtained based on the coordinate information of the midpoint O when the AGV stops and the coordinate information of the intersection point A.

[0034] like Figure 3 As shown, when turning, the running directions of the two drive units need to be tangent to the rotation circle. ∠c is the rotation angle of the first drive unit 1, and the rotation angle of the second drive unit 2 is 180° - ∠c. Therefore, the control algorithm for turning needs to calculate ∠c. According to trigonometric functions, the rotation trajectory is an arc with the intersection point A as the center and a radius of r, where the radius r² = (L / 2)² + M. 2 , ∠b=arcos(M / r)*(180 / π), and we know from the supplementary angle relationship that ∠c=∠b=α.

[0035] Then, with the direction in front of the AGV's current travel direction defined as 0° (i.e., the direction of the extension of the center line Y along the AGV's travel direction is defined as 0°), the first drive unit 1 is controlled to rotate by an angle α, and the second drive unit 2 is controlled to rotate by an angle β.

[0036] The first drive unit 1 and the second drive unit 2 are driven to move in opposite directions at the same speed to start turning; when turning, when the AGV's sensor module detects the signal of the second magnetic track 4, the turn is completed, the first drive unit 1 and the second drive unit 2 return to the center and travel along the second magnetic track 4.

[0037] Example 2:

[0038] See Figures 1 to 3 This embodiment also provides a storage device for executing the turning method of Embodiment 1 above. The storage device stores multiple execution instructions, which are used to control the module to load and perform the following operations:

[0039] like Figure 1 As shown, the AGV travels along the first magnetic track 3, ensuring that the midpoint O overlaps with the center line Y, and the arrow indicates the direction of the AGV's travel.

[0040] like Figure 2 As shown, the AGV stops after receiving a turning signal. In one specific embodiment, a turn card is configured on the first magnetic track 3. When the landmark card reader on the AGV reads the turn card, a turning signal is generated.

[0041] like Figure 3 As shown, the distance M between the intersection point A and the midpoint O is then obtained, and the radius of the rotation circle is calculated. Angle α = arcos(M / r)*(180 / π), angle β = (180-α)*-1; the branch card is preset with the coordinate information of the intersection point A, and the spacing M is calculated by the coordinate information fed back by the branch card. For example, the spacing M can be directly obtained based on the coordinate information of the midpoint O when the AGV stops and the coordinate information of the intersection point A.

[0042] like Figure 3 As shown, when turning, the running directions of the two drive units need to be tangent to the rotation circle. ∠c is the rotation angle of the first drive unit 1, and the rotation angle of the second drive unit 2 is 180° - ∠c. Therefore, the control algorithm for turning needs to calculate ∠c. According to trigonometric functions, the rotation trajectory is an arc with the intersection point A as the center and a radius of r, where the radius r² = (L / 2)² + M. 2 , ∠b=arcos(M / r)*(180 / π), and we know from the supplementary angle relationship that ∠c=∠b=α.

[0043] Then, with the direction in front of the AGV's current travel direction defined as 0° (i.e., the direction of the extension of the center line Y along the AGV's travel direction is defined as 0°), the first drive unit 1 is controlled to rotate by an angle α, and the second drive unit 2 is controlled to rotate by an angle β.

[0044] The first drive unit 1 and the second drive unit 2 are driven to move in opposite directions at the same speed to start turning; when turning, when the AGV's sensor module detects the signal of the second magnetic track 4, the turn is completed, the first drive unit 1 and the second drive unit 2 return to the center and travel along the second magnetic track 4.

[0045] Compared with the prior art, the present invention provides a turning method that can rotate around a non-axial center, thus avoiding the problem of turning deviation caused by the non-overlapping intersection of the midpoints of the two drive units of the AGV and the center lines of the two magnetic tracks, thereby improving the AGV's adaptability to the scene, enhancing its versatility, and ensuring the accuracy of turning.

[0046] Based on the disclosure and teachings of the foregoing specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on the present invention.

Claims

1. A method for an AGV to turn around a circle rotating around a non-axial center, wherein the center distance between the axes of the first drive unit and the second drive unit of the AGV is L, the midpoint is O, the centerline of the first magnetic track is Y, the centerline of the second magnetic track is X, X and Y are perpendicular and their intersection point is A, characterized in that... Includes the following steps: The AGV travels along the first magnetic track, causing the midpoint O to overlap with the center line Y; The AGV stops upon receiving a turn signal. Obtain the distance M between the intersection point A and the midpoint O, and calculate the radius of the rotating circle, angle α = arcos(M / r)*(180 / π), and angle β = (180-α)*-1; With the forward direction of the AGV's current travel direction as 0°, control the rotation angle α of the first drive unit and the rotation angle β of the second drive unit; The first and second drive units are driven to move in opposite directions at the same speed to begin turning; When the landmark card reader on the AGV reads the branch road card, it generates a turning signal; The branch road card is pre-set with the coordinate information of the intersection point A, and the distance M is calculated using the coordinate information fed back by the branch road card.

2. The AGV turning method according to claim 1, characterized in that, When turning, the AGV completes the turn when its sensor module detects the signal of the second magnetic track, and the first and second drive units return to center and travel along the second magnetic track.

3. A storage device for implementing the AGV turning method of claim 1, which involves rotating around a non-axial center, wherein the storage device stores multiple execution instructions, characterized in that... The execution instructions are used to control the module to load and perform the following operations: The AGV travels along the first magnetic track, causing the midpoint O to overlap with the center line Y; The AGV stops upon receiving a turn signal. Obtain the distance M between the intersection point A and the midpoint O, and calculate the radius of the rotating circle, angle α = arcos(M / r)*(180 / π), and angle β = (180-α)*-1; With the forward direction of the AGV's current travel direction as 0°, control the rotation angle α of the first drive unit and the rotation angle β of the second drive unit; The first drive unit and the second drive unit are driven to move in opposite directions at the same speed, and the turn begins.

4. The storage device according to claim 3, characterized in that, Once the landmark card reader on the AGV reads the branch road card, a turning signal is generated.

5. The storage device according to claim 4, characterized in that, The branch road card is pre-set with the coordinate information of the intersection point A, and the distance M is calculated using the coordinate information fed back by the branch road card.

6. The storage device according to claim 3, characterized in that, When turning, the AGV completes the turn when its sensor module detects the signal of the second magnetic track, and the first and second drive units return to center and travel along the second magnetic track.

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