Wall climbing robot special-shaped magnetic tile

Abstract

The present application relates to the technical field of magnetic shoe of wall-climbing robot, in particular to a special-shaped magnetic shoe of wall-climbing robot. The present application breaks through the non-uniform central angle permanent magnet arrangement structure, combines the adjacent permanent magnet radial reverse magnetization strategy, constructs an efficient closed magnetic circuit inside the magnetic shoe, thereby avoiding the symmetric magnetic field distribution mode of the traditional magnetic shoe, forcing the magnetic induction lines to densely converge along the preset path, significantly suppressing the edge magnetic leakage phenomenon, making the horizontal direction magnetic flux density jump up, and fundamentally reconstructing the magnetic field gradient distribution, providing the wall-climbing robot with revolutionary anti-skid traction force guarantee.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of magnetic shoe of wall-climbing robot, and particularly relates to a special-shaped magnetic shoe of wall-climbing robot. BACKGROUND

[0002] In the daily maintenance work such as rust removal, cleaning and painting of large steel structure vertical surfaces of ships, storage tanks and the like, the traditional manual operation is not only low in efficiency, but also has a great safety risk, and is difficult to meet the needs of modern industry. With the rapid development of robot technology, vertical surface walking robots have gradually become an important tool for these maintenance work, which usually adopts permanent magnetic adsorption mode to ensure stable operation on the surface of steel structure and avoid the risk of robot falling caused by sudden power failure of electromagnetic body.

[0003] However, the magnetic shoe in the prior art has many deficiencies. For example, the permanent magnetic adsorption unit magnetic shoe disclosed in a patent (202210394799.1) of a ship ultra-high pressure water cleaning wheeled wall-climbing robot has problems such as large weight, small generated magnetic force, low supportable weight and the like, which is not conducive to the safe and stable operation of the robot under heavy load.

[0004] Therefore, in order to solve these problems, a magnetic shoe is designed in patent 202411428251.X, which is composed of five magnets and divided into three groups of different magnetic shoes. The back of the magnetic shoe body is a circular arc structure, and the bottom is a horizontal structure. By reasonably distributing the central angle proportion of the three groups of magnetic shoes, optimizing the height of the magnetic blocks, and adopting Halbach circular arc array magnetization direction and the like, the special-shaped magnetic shoe has the characteristics of large magnetic force, small weight and small size. However, the high-efficiency closed magnetic circuit is not constructed in the magnetic shoe, the magnetic flux lines are denser than those of the traditional magnetic shoe, but there is still an edge magnetic leakage phenomenon. From the magnetic field distribution, the magnetic flux lines mainly rely on the directional arrangement of the Halbach array to realize local strengthening, but the magnetic circuit structure along the preset path is not formed, resulting in the loss of part of the magnetic force in the non-working area. Especially, the magnetic flux density in the horizontal direction is limited. For the wall-climbing robot, this non-closed magnetic circuit design cannot provide enough horizontal direction traction, and in the climbing or anti-skid working condition, the magnetic force decays quickly, and the distance sensitivity is high, which restricts the stability of the heavy load operation of the robot in the complex wall surface environment. Therefore, it is urgent to solve. SUMMARY

[0005] In order to avoid and overcome the technical problems existing in the prior art, the present application provides a special-shaped magnetic shoe of wall-climbing robot. The present application constructs a high-efficiency closed magnetic circuit in the magnetic shoe by means of the breakthrough non-uniform central angle permanent magnet arrangement and the adjacent permanent magnet radial reverse magnetization strategy.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0007] The wall-climbing robot special-shaped magnetic tile comprises a plurality of permanent magnets arranged in sequence along the circumferential direction of the wheel of the wall-climbing robot and each being a fan-shaped ring segment, the central angles of adjacent permanent magnets are different, and each permanent magnet cooperates with each other to form a fan-shaped structure; the magnetization directions of each permanent magnet respectively depart from or point to the center of the fan-shaped structure, and the magnetization directions of adjacent permanent magnets are arranged in opposite directions.

[0008] As a further scheme of the present application: the sum of the central angles of the permanent magnets with the magnetization direction departing from the center is greater than the sum of the central angles of the permanent magnets with the magnetization direction pointing to the center.

[0009] As a further scheme of the present application: the total magnetic attraction force between the special-shaped magnetic tile and the current wall surface climbed by the wheel is :

[0010] (1) ;

[0011] In the formula, represents the magnetic circuit coupling coefficient; represents the vacuum permeability; represents the magnetization direction coefficient of the first permanent magnet, 1 when departing from the center and -1 when pointing to the center; represents the total number of permanent magnets in the special-shaped magnetic tile; represents the residual magnetism induction intensity of the first permanent magnet; represents the effective magnetic attraction area of the first permanent magnet; represents the cosine function; represents the central angle of the first permanent magnet; represents the edge effect correction coefficient of the special-shaped magnetic tile; represents the average magnetic induction intensity of the surface of the special-shaped magnetic tile; represents the effective arc length of the special-shaped magnetic tile; h represents the axial thickness of the permanent magnet.

[0012] As a further scheme of the present application: the effective magnetic attraction area is calculated as follows:

[0013] (2) ;

[0014] In the formula, represents the outer circle radius of the special-shaped magnetic tile.

[0015] As a further scheme of the present application: the effective arc length of the special-shaped magnetic tile is calculated as follows:

[0016] (3) ;

[0017] In the formula, The central angle of the special-shaped magnetic tile.

[0018] As a further scheme of the present application: the permanent magnets are three or more in total, and the magnetization directions of the permanent magnets at both ends are away from the center.

[0019] As a further scheme of the present application: the axial thickness and the radial thickness of each permanent magnet are the same.

[0020] As a further scheme of the present application: the special-shaped magnetic tile is formed with a tangent plane parallel to the current wall surface being climbed, and the distance between the tangent plane and the current wall surface is the magnetic attraction distance.

[0021] As a further scheme of the present application: the special-shaped magnetic tile is located at the side of the wheel contacting the current wall surface being climbed.

[0022] As a further scheme of the present application: the adjacent permanent magnets are adhered and fixed to each other by glue.

[0023] As a further scheme of the present application: the centers of the permanent magnets coincide with each other.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] The arrangement mode of the concentric fan-shaped ring segments in the present application provides a geometric basis for the directional flow of the magnetic induction lines, so that the magnetic induction lines can be distributed in order along the circumferential direction. The magnetization directions of the permanent magnets are respectively directed to or away from the center of the fan-shaped structure, and the magnetization directions of the adjacent permanent magnets are arranged in opposite directions, forming an alternating arrangement of "N pole-adjacent S pole", so that the magnetic induction lines can flow naturally from the N pole of one permanent magnet to the S pole of the adjacent permanent magnet, and through the sequential connection of the multiple permanent magnets, the magnetic induction lines form a continuous path inside the magnetic tile. By adjusting the magnetic flux proportion of the permanent magnets with different magnetization directions, the balance and convergence of the magnetic flux in the magnetic circuit are ensured, and the leakage of the magnetic induction lines due to the imbalance of the magnetic flux is avoided. Then, starting from the permanent magnet at one end away from the center, the magnetic induction lines are transmitted through the intermediate alternating permanent magnets, and finally form a closed loop at the permanent magnet at the other end away from the center, reducing the edge magnetic leakage. Then, through the equal thickness setting of the permanent magnets, the consistency of the magnetic circuit cross section is reduced to reduce the loss of the magnetic induction lines in the transmission process; finally, through the stable magnetic attraction distance, the effective coupling between the magnetic circuit and the adsorption surface is ensured, so that the closed magnetic circuit not only forms inside the magnetic tile, but also forms a complete magnetic induction line closed loop with the external adsorption surface, significantly improving the magnetic circuit utilization rate. Therefore, through the combined design of "adjacent opposite magnetization + concentric fan-shaped arrangement + center angle proportion control + odd-even number and two-end magnetization direction limitation", a closed magnetic circuit with dense convergence of the magnetic induction lines along the preset path is realized, the magnetic leakage is effectively suppressed, and the magnetic force utilization efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1Is the assembly structure diagram of the special-shaped magnetic tile and the vehicle body in the present application.

[0027] Figure 2 Is the overall structure diagram of the special-shaped magnetic tile in the present application.

[0028] Figure 3 Is the assembly structure diagram of each permanent magnet in the present application.

[0029] Figure 4 Is the internal cross-section magnetic induction line diagram of the special-shaped magnetic tile in the present application.

[0030] Figure 5 Is the magnetic induction intensity diagram of the special-shaped magnetic tile in the present application.

[0031] In the figure: 10, vehicle frame; 11, wheel; 20, fixed support; 21, arc-shaped groove; 30, magnetic tile body; 31, first permanent magnet; 32, second permanent magnet; 33, third permanent magnet; 34, fourth permanent magnet; 35, fifth permanent magnet; 36, sixth permanent magnet; 37, seventh permanent magnet; 38, eighth permanent magnet; 39, ninth permanent magnet. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0033] As shown in Figure 1 and Figure 2 , in the present embodiment, the installation of the special-shaped magnetic tile is based on the fixed support 20, which is installed on the vehicle frame 10 and has an arc-shaped groove 21. The arc-shaped groove 21 and the wheel 11 shaft at its location are coaxially arranged with each other, and the special-shaped magnetic tile is fixedly installed in such an arc-shaped groove 21. The magnetic tile body 30 of the special-shaped magnetic tile includes a plurality of permanent magnets, each of which is arranged in sequence along the length direction of the arc-shaped groove 21, and each is a fan-shaped ring segment, the cross section of which is perpendicular to the wheel 11 shaft, and the axial side surfaces of adjacent permanent magnets are in contact with each other to form the special-shaped magnetic tile. At the same time, each permanent magnet has a radial symmetry plane, which is perpendicular to the cross section and passes through the center of the fan-shaped circle. The vehicle frame 10 runs on the current climbing wall surface 40, at this time the special-shaped magnetic tile is located at the contact side of the wheel 11, so as to directly transmit magnetic force to the driving point and improve the stability of movement.

[0034] As shown in Figure 3As shown, the magnetic tile body 30 includes a first permanent magnet 31, a second permanent magnet 32, a third permanent magnet 33, a fourth permanent magnet 34, a fifth permanent magnet 35, a sixth permanent magnet 36, a seventh permanent magnet 37, an eighth permanent magnet 38 and a ninth permanent magnet 39. The first permanent magnet 31, the third permanent magnet 33, the sixth permanent magnet 36 and the eighth permanent magnet 38 are four permanent magnets with the same shape but different magnetizing directions. The first permanent magnet 31 and the fourth permanent magnet 34 are two permanent magnets with the same shape and magnetizing directions pointing to the center of the circle. The fifth permanent magnet 35, the seventh permanent magnet 37 and the ninth permanent magnet 39 are three permanent magnets with the same shape but different magnetizing directions. Each permanent magnet is arranged according to Figure 3 The arrangement shown is arranged in the arc groove 21 in sequence, and the magnetization direction is alternately arranged from left to right away from the center of the circle and toward the center of the circle. The specific magnetization direction is as follows Figure 3 The large arrows in each permanent magnet point to the direction shown. The first permanent magnet 31 and the third permanent magnet 33 are symmetrically arranged on both sides of the second permanent magnet 32, the second permanent magnet 32 ​​and the fourth permanent magnet 34 are symmetrically arranged on both sides of the third permanent magnet 33, the fifth permanent magnet 35 and the seventh permanent magnet 37 are symmetrically arranged on both sides of the sixth permanent magnet 36, and the seventh permanent magnet 37 and the ninth permanent magnet 39 are symmetrically arranged on both sides of the eighth permanent magnet 38. Figure 3 in It represents the magnetic attraction distance between the special-shaped magnetic tile and the current climbing wall 40, and in this embodiment, the value is 5mm.

[0035] Adjacent permanent magnets are adhered to each other by glue, so a certain gap is generated. In this embodiment, the gap is 0.1 mm, which can be ignored.

[0036] like Figure 3 As shown, the back of the magnetic tile body 30 is also an arc, and its arc radius is 120mm. The radius of the outer circumference of the magnetic tile body 30 is The central angle of the magnetic tile body 30 is 130 mm. The angle is 145° and is distributed to each permanent magnet in a certain corresponding proportion.

[0037] The ratio of the central angles of the first permanent magnet 31, the second permanent magnet 32, the third permanent magnet 33, the fourth permanent magnet 34, the fifth permanent magnet 35, the sixth permanent magnet 36, the seventh permanent magnet 37, the eighth permanent magnet 38 and the ninth permanent magnet 39 is 3:1:3:1:5:3:5:3:5, that is, the central angles of the first permanent magnet 31, the second permanent magnet 32, the third permanent magnet 33, the fourth permanent magnet 34, the fifth permanent magnet 35, the sixth permanent magnet 36, the seventh permanent magnet 37, the eighth permanent magnet 38 and the ninth permanent magnet 39 are 15°, 5°, 15°, 5°, 25°, 15°, 25°, 15° and 25°, respectively.

[0038] like Figure 4 andFigure 5 As shown, the magnetic attraction of the magnetic shoe is analyzed by using simulation software, and the internal profile magnetic induction line diagram and the magnetic induction intensity diagram of the magnetic shoe are obtained. The embodiment is based on Ansys Maxwell software, and the finite element method is used to solve the 3D static magnetic field. The main solving basis is Maxwell equation, boundary condition and medium constitutive equation, and the final target is to calculate the magnetic attraction of the permanent magnet to the wall surface. According to Maxwell tension method, the corresponding magnetic attraction of the permanent magnet to the wall surface is obtained. Then, combined with the parameters of the magnetic shoe, the total magnetic attraction calculation formula shown in formula (1) is fitted.

[0039] Figure 4 The measured edge magnetic induction line inclination is 48°, so the normal magnetic field decay rate can be calculated as 0.331, combined with the first permanent magnet 31, the third permanent magnet 33, the seventh permanent magnet 37 and the ninth permanent magnet 39, and the total proportional coefficient of the four is 16 / 29≈0.552, the superposition material factor is 1.1, and then the total magnetic attraction of the magnetic shoe to the wall surface is calculated as 0.203. Directly reading the magnetic induction intensity distribution diagram of the center , it can be seen that the center peak value, i.e. the magnetic induction intensity of the fifth permanent magnet 35, is about 1.52 T, the magnetic induction intensity of the ninth permanent magnet 39 is about 0.93 T, and the lowest magnetic induction intensity in the magnetic shoe body 30 is about 0.38 T, and the weighted average is 0.9 T (covering 145° of the special-shaped magnetic shoe). Figure 5

[0040] Through the analysis of Figure 4 and Figure 5 , it can be seen that without changing the fan basic shape of the magnetic shoe, the horizontal magnetic force of the magnetic shoe is greatly improved, and the climbing ability of the wall climbing robot is enhanced. The wall climbing robot adopts a non-contact permanent magnetic adsorption unit, and the advantage of this method is that the magnetic force is variable, which makes up for the disadvantage that the magnetic force of the permanent magnet is constant. In this embodiment, the relationship between the magnetic force and the distance is analyzed by using the finite element software, and the simulation analysis of the magnetic field intensity around the permanent magnetic unit is completed.

[0041] Parameter value: magnetic circuit coupling coefficient , the value range is [0.8, 1.2], and the value in this embodiment is the middle value 1. Vacuum permeability , the value is 4 -7 × 10 π H / m. The magnetic direction coefficient , taking 1 away from the center of the circle and-1 pointing to the center of the circle, the specific value is shown in Table 1. The total number of permanent magnets in the special-shaped magnetic shoe , the value in this embodiment is 9. The residual magnetic induction intensity of the permanent magnet , the value of all permanent magnets in this embodiment is 1.2T. The effective magnetic attraction area of the permanent magnet ​​, the calculation results are shown in Table 1. The central angle of the permanent magnet , the values are shown in Table 1, and the corresponding radian values are converted for the calculation of formula (2) and formula (3). The edge effect correction coefficient of the special-shaped magnet tile , the value is 0.203. The average magnetic induction intensity of the surface of the special-shaped magnet tile , the value is 0.9 T. The effective arc length of the special-shaped magnet tile , the calculation result of the embodiment is 329 mm. The axial thickness of the permanent magnet h , the value is 20 mm. The outer circle radius of the special-shaped magnet tile , the value is 130 mm. The central angle of the special-shaped magnet tile , the value is 145°. The permanent magnet adopts N42 grade neodymium iron boron permanent magnet.

[0042] Table 1. Various parameters of the permanent magnet

[0043] ;

[0044] It can be known by substituting the above data into formula (1) that the total magnetic attraction force of the special-shaped magnet tile to the current climbing wall 40 is about 1582 N, and the error of the magnetic attraction force of about 1500 N shown in Figure 5 is about 4%<5%, which is within the acceptable error range. It can be seen that the total magnetic attraction force calculation formula in the present application can accurately calculate the corresponding magnetic attraction force.

[0045] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent replacement or change according to the technical solution and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A special-shaped magnetic tile for a wall-climbing robot, characterized in that: The invention comprises a plurality of permanent magnets arranged in sequence along the circumference of the wall-climbing robot wheel and all of which are in the shape of sector ring segments. The central angles of adjacent permanent magnets are different, and the permanent magnets cooperate with each other to form a sector structure. The magnetization direction of each permanent magnet is respectively away from or toward the center of the sector structure, and the magnetization directions of adjacent permanent magnets are arranged in opposite directions. The total magnetic attraction between the special-shaped magnetic tile and the current climbing wall of the wheel is ; ； Where, represents the magnetic circuit coupling coefficient; represents the vacuum permeability; Indicates the The magnetization direction coefficient of a permanent magnet is 1 when it points away from the center of the circle and -1 when it points towards the center of the circle. Indicates the total number of permanent magnets in the special-shaped magnetic tile; Indicates the The residual magnetic induction intensity of a permanent magnet; Indicates the The effective magnetic attraction area of ​​a permanent magnet; represents the cosine function; Indicates the The central angle of the permanent magnet; Indicates the edge effect correction coefficient of the special-shaped magnetic tile; Indicates the average magnetic induction intensity on the surface of the special-shaped magnetic tile; Indicates the effective arc length of the special-shaped magnetic tile; Indicates the axial thickness of the permanent magnet.

2. The special-shaped magnetic tile of a wall-climbing robot according to claim 1, characterized in that: In the fan-shaped structure, the sum of the central angles of the permanent magnets whose magnetization directions are away from the center of the circle is greater than the sum of the central angles of the permanent magnets whose magnetization directions are toward the center of the circle.

3. The special-shaped magnetic tile of a wall-climbing robot according to claim 2, characterized in that: The effective magnetic attraction area is calculated as follows: ； Where, Indicates the outer radius of the special-shaped magnetic tile.

4. The special-shaped magnetic tile of a wall-climbing robot according to claim 3, characterized in that: The effective arc length of the special-shaped magnetic tile is calculated as follows: ； Where, Indicates the center angle of the special-shaped magnetic tile.

5. The special-shaped magnetic tile of a wall-climbing robot according to claim 4, characterized in that: There are more than three permanent magnets, the total number is an odd number, and the magnetization directions of the permanent magnets located at both ends are away from the center of the circle.

6. The special-shaped magnetic tile of a wall-climbing robot according to claim 5, characterized in that: The axial thickness and radial thickness of each permanent magnet are the same.

7. The special-shaped magnetic tile of a wall-climbing robot according to claim 6, characterized in that: A section parallel to the current climbing wall is formed on the special-shaped magnetic tile, and the distance between the section and the current climbing wall is the magnetic attraction distance.

8. The special-shaped magnetic tile of a wall-climbing robot according to claim 7, characterized in that: Adjacent permanent magnets are bonded to each other by glue.

9. The special-shaped magnetic tile of a wall-climbing robot according to claim 8, characterized in that: The centers of the permanent magnets coincide with each other.

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