Mobile robot floating pin-type vector control high-precision docking device and method

Abstract

The present invention discloses a mobile robot floating lift pin type vector controlled high-precision docking device and method, comprising: a base; a floating lift pin is fixedly provided at the middle position of the top end of the base, a plurality of brackets are symmetrically arranged on the top of the base, a plurality of brackets are fixedly provided with magnet grooves at one end, and a plurality of magnet grooves are fixedly provided with tile-shaped magnets inside. The mobile robot floating lift pin type vector controlled high-precision docking device and method of the present invention can achieve high-precision docking of an automatic parking mobile robot or other types of mobile robots with a docking target with higher precision, lower cost, lower computing power and smaller volume, and has high precision, wide applicability and little influence by environmental changes (such as movement of surrounding objects, movement of people, changes in light, etc.).

Description

Technical Field

[0001] The invention relates to a docking device, in particular to a floating pin-lifting vector-controlled high-precision docking device and method for a mobile robot. Background Art

[0002] In actual use, mobile robots need to carry pallets, robotic arms and other docking objects. In some occasions, the docking objects need to have a certain positioning accuracy. For example, robotic arms require high-precision docking to ensure stability. The current mainstream docking methods are mainly QR code vision and laser scanning.

[0003] Although the measurement accuracy of QR code vision is high (less than 1mm), it has defects such as small field of view, high sensor price, low rotation angle accuracy, and great influence of light.

[0004] Although laser scanning has high accuracy, the sensor is extremely expensive and is not suitable for scenarios with frequent environmental changes.

[0005] This method uses a combination of mechanical and electrical measurement methods, which has high accuracy, low cost, strong flexibility (the shape of the ejector pin can be changed), and little interference from environmental changes. It is very suitable for the docking of certain mobile robots with specific targets, such as the docking of automatic parking mobile robots and vehicle carriers.

[0006] It should be noted that the above contents belong to the technical knowledge of the inventor and do not necessarily constitute prior art. Summary of the invention

[0007] In order to solve the above problems, the purpose of the present invention is to provide a mobile robot floating pin-type vector control high-precision docking device and method.

[0008] To achieve the above object, the present invention proposes a mobile robot floating pin-type vector control high-precision docking device and method, comprising:

[0009] Base;

[0010] A floating ejector pin is fixedly provided at the middle position of the top of the base, a plurality of brackets are symmetrically provided on the top of the base, a magnet groove is fixedly provided at one end of each of the brackets, a tile-shaped magnet is fixedly provided inside each of the magnet grooves, a strain gauge is fixedly provided at the bottom of each of the magnet grooves, the outside of the base is covered with an outer shell, and the top of the floating ejector pin passes through the outer shell and is placed outside the outer shell.

[0011] In one example, the top position of the floating lift pin is a non-magnetic area, and the bottom position of the floating lift pin is a magnetic area. In the magnetic part, the outer ring and the inner ring are of different magnetic poles, but the outer ring and the inner ring of the external tile magnet are of the same level, and the same levels repel each other.

[0012] In one example, the inner and outer circles of the tile-shaped magnets placed in the magnet slots have different magnetic poles, and the inner circles of all magnets are at the same pole.

[0013] In one example, the housing is used to limit the axial movement of the floating ejector pin, so that the floating ejector pin can only be displaced in one plane.

[0014] In one example, the working method process steps are as follows:

[0015] Step 1: The floating ejector pin contacts the docking target, causing an offset;

[0016] Step 2: The repulsive force between the top pin and the tile magnets changes;

[0017] Step 3: Get the new support beam strain;

[0018] Step 4: Calculate the position of the floating ejector pin based on the new strain;

[0019] Step 5: Control the mobile robot to make fine adjustments;

[0020] Step 6: Wait until the floating ejector pin returns to the center.

[0021] In one example, the floating ejector pin can be displaced in any direction within the plane, but is subject to the repulsive force of the surrounding magnets of the same level. The greater the displacement, the greater the repulsive force.

[0022] The beams supporting each magnet are attached with high-precision stress strain gauges. The resistance change output by the strain gauges can be conditioned and amplified by a variety of circuits according to the formula:

[0023]

[0024] To obtain the strain ε, where is the relative change in resistance, μ is the Poisson coefficient, is the relative change in resistivity.

[0025] The same goes for the other beams, and thus the strain ε of the eight supporting beams can be obtained.

[0026] In one example, when the floating ejector pin is in the middle, the eight strains should be almost equal. Assuming that the strain at this time is, when the floating ejector pin is displaced in one direction by a distance d due to contact with the tapered hole of the docking target, the strain measured at each point is, i = 1 to 8. At this time, according to each point, the displacement direction and magnitude of the mobile robot body carrying the floating ejector pin relative to the docking target can be inferred by referring to the pre-calibrated data.

[0027] The mobile robot floating pin-type vector control high-precision docking device and method proposed by the present invention can bring the following beneficial effects:

[0028] The present invention can achieve high-precision docking of an automatic parking mobile robot or other types of mobile robots with a docking target with higher accuracy, lower cost, lower computing power, and smaller volume. It has high accuracy, wide applicability, and is less affected by environmental changes (such as movement of surrounding objects, movement of people, changes in light, etc.). BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings described herein are used to provide a further understanding of the present invention and constitute a part 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:

[0030] Figure 1 It is a schematic diagram of the top view of the structure of the present invention;

[0031] Figure 2 It is a schematic diagram of the side structure of the present invention;

[0032] Figure 3 It is a schematic diagram of the overall structure of the present invention;

[0033] Figure 4 It is a flow chart of the working method of the present invention;

[0034] Figure 5 The present invention provides a docking process between a mobile robot equipped with a floating ejector pin and a docking object;

[0035] Figure 6 It is a schematic diagram of the application mode of the present invention;

[0036] Figure 7 Schematic diagram of the application of the automatic parking mobile robot of the present invention. DETAILED DESCRIPTION

[0037] In order to more clearly illustrate the overall concept of the present invention, a detailed description is given below in an exemplary manner in conjunction with the accompanying drawings.

[0038] In the description of the present invention, it is necessary to understand that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0039] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0040] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the present invention, unless otherwise clearly specified and limited, the first feature "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one scheme", "some schemes", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the scheme or example are included in at least one scheme or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same scheme or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more schemes or examples in a suitable manner.

[0042] like Figure 1 to Figure 7 As shown, the embodiment of the present invention provides a mobile robot floating pin-type vector control high-precision docking device and method, including:

[0043] Base;

[0044] A floating ejector pin is fixedly provided at the middle position of the top of the base, a plurality of brackets are symmetrically provided on the top of the base, a magnet groove is fixedly provided at one end of each of the brackets, a tile-shaped magnet is fixedly provided inside each of the magnet grooves, a strain gauge is fixedly provided at the bottom of each of the magnet grooves, the outside of the base is covered with an outer shell, and the top of the floating ejector pin passes through the outer shell and is placed outside the outer shell.

[0045] Specifically, the top position of the floating lift pin is a non-magnetic area, and the bottom position of the floating lift pin is a magnetic area. In the magnetic part, the outer ring and the inner ring are of different magnetic poles, but the outer ring and the inner ring of the external tile-shaped magnet are of the same level, and the same levels repel each other.

[0046] Specifically, the inner and outer circles of the tile-shaped magnets placed in the magnet slots have different magnetic poles, and the inner circles of all the magnets are at the same level.

[0047] Specifically, the housing is used to limit the axial movement of the floating ejector pin, so that the floating ejector pin can only be displaced in one plane.

[0048] Specifically, the working method process steps are as follows:

[0049] Step 1: The floating ejector pin contacts the docking target, causing an offset;

[0050] Step 2: The repulsive force between the top pin and the tile magnets changes;

[0051] Step 3: Get the new support beam strain;

[0052] Step 4: Calculate the position of the floating ejector pin based on the new strain;

[0053] Step 5: Control the mobile robot to make fine adjustments;

[0054] Step 6: Wait until the floating ejector pin returns to the center.

[0055] Specifically, the floating ejector pin can be displaced in any direction within the plane, but is subject to the repulsive force of the surrounding magnets of the same level. The greater the displacement, the greater the repulsive force.

[0056] The beams supporting each magnet are attached with high-precision stress strain gauges. The resistance change output by the strain gauges can be conditioned and amplified by a variety of circuits according to the formula:

[0057]

[0058] To obtain the strain ε, where is the relative change in resistance, μ is the Poisson coefficient, is the relative change in resistivity.

[0059] The same goes for the other beams, and thus the strain ε of the eight supporting beams can be obtained.

[0060] Specifically, when the floating ejector pin is in the middle, the eight strains should be almost equal. Assuming that the strain at this time is, when the floating ejector pin is displaced in one direction by a distance d due to contact with the tapered hole of the docking target, the strain measured at each point is, i = 1 to 8. At this time, according to each point, the displacement direction and magnitude of the mobile robot body carrying the floating ejector pin relative to the docking target can be inferred by referring to the pre-calibrated data.

[0061] The calibration method adopts the orthogonal experimental method.

[0062] 1. The pushing direction remains unchanged, and the pushing distance gradually increases, and 8 sets of data with different distances are obtained.

[0063] 2. Push the distance component, and the pushing direction increases from 0 to 360, and obtain 8 sets of data at different distances.

[0064] Finally, the curve is fitted, the horizontal coordinate of the curve is the pushing direction (0°-360°), the vertical coordinate is, the pushing direction corresponding to the maximum value of the vertical coordinate is the direction of the ejector pin displacement, the maximum value multiplied by the fuzzy coefficient is the size of the ejector pin displacement, and the fuzzy coefficient is obtained from the calibration.

[0065] If the computing power of some mobile robot controllers is limited, we can use table lookup and interpolation methods to determine the final ejector pin offset, direction, and size;

[0066] Application:

[0067] The following flowchart shows the docking process between a mobile robot equipped with a floating ejector pin and a docking object:

[0068] Step 1: The mobile robot drives under the docking object and prepares for docking;

[0069] Step 2: Rough positioning of the mobile robot (QR code or laser, etc.);

[0070] Step 3: The mobile robot lifts the floating ejector pin (single or multiple);

[0071] Step 4: Calculate the displacement vector of each floating ejector pin;

[0072] Step 5: Vector merging to calculate the deviation of the mobile robot relative to the docking object;

[0073] Step 6: If the relative deviation data is qualified, the docking is completed and the robot performs subsequent actions; if it is not qualified, the robot is moved to adjust the posture and the process is repeated: the displacement vector of each floating ejector pin is calculated.

[0074] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0075] The above description is only an 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 substitution, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims

1. Mobile robot floating pin-type vector control high-precision docking device, including: Base; The invention is characterized in that: a floating ejector pin is fixedly provided at the middle position of the top of the base, a plurality of brackets are symmetrically provided at the top of the base, a magnet slot is fixedly provided at one end of each of the brackets, a tile-shaped magnet is fixedly provided inside each of the magnet slots, a strain gauge is fixedly provided at the bottom of each of the magnet slots, the base is covered with a shell, and the top of the floating ejector pin passes through the shell and is placed outside the shell; The top position of the floating lift pin is a non-magnetic area, and the bottom position of the floating lift pin is a magnetic area. In the magnetic part, the outer ring and the inner ring have different magnetic poles, but the outer ring and the inner ring of the external tile-shaped magnet are at the same level, and the same levels repel each other.

2. According to claim 1, a mobile robot floating pin-type vector-controlled high-precision docking device is characterized in that: The inner and outer circles of the tile-shaped magnets placed in the magnet slots have different magnetic poles, and the inner circles of all magnets are at the same level.

3. The mobile robot floating pin-type vector-controlled high-precision docking device according to claim 2 is characterized in that: The housing is used to limit the axial movement of the floating ejector pin, so that the floating ejector pin can only be displaced in one plane.

4. The docking method of the mobile robot floating pin-type vector-controlled high-precision docking device according to claim 1, characterized in that: The steps of the docking method are as follows: Step 1: The floating ejector pin contacts the docking target, causing an offset; Step 2: The repulsive force between the top pin and the tile magnets changes; Step 3: The beams supporting each magnet are attached with high-precision stress strain gauges to obtain the new support beam strain; Step 4: Calculate the position of the floating ejector pin based on the new strain; Step 5: Control the mobile robot to make fine adjustments; Step 6: Wait until the floating ejector pin returns to the center.

5. The docking method of the mobile robot floating pin-type vector-controlled high-precision docking device according to claim 4, characterized in that: The floating ejector pin can be displaced in any direction within the plane, but it is subject to the repulsive force of the surrounding magnets of the same level. The greater the displacement, the greater the repulsive force. The resistance change of the strain gauge output can be conditioned and amplified by a variety of circuits according to the formula: ； To get strain ,in , is the relative change in resistance, is the Poisson coefficient, which is the relative change in resistivity; The same is true for the other beams, so the strains of the eight supporting beams can be obtained .

6. The docking method of the mobile robot floating pin-type vector-controlled high-precision docking device according to claim 4, characterized in that: When the floating ejector pin is in the middle, the eight strains are equal in magnitude. Assuming that the strain at this time is, when the floating ejector pin is displaced a distance d in one direction due to contacting the tapered hole of the docking target object, the strain measured at each point is; at this time, based on each point, the displacement direction and magnitude of the mobile robot body carrying the floating ejector pin relative to the docking target object can be inferred by referring to the pre-calibrated data.

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