Multi-mode McKibben locomotion and roller design for pipe robots

Abstract

The application discloses a multi-mode McKenna action device and roller design method of a pipeline robot, and the action device comprises a support, a McKenna driving wheel and an omnidirectional load wheel which are installed side by side on the support; the McKenna driving wheel comprises a driving wheel shaft, a driving wheel shell and a plurality of rollers A; the omnidirectional load wheel comprises a load wheel shaft, a load wheel shell and a plurality of rollers B; the plurality of rollers A of the McKenna driving wheel are installed on the outer circumferential surface of the driving wheel shell, and the rollers A adopt a McKenna wheel type layout, that is, the axis of the roller A and the generatrix of the corresponding cylindrical shell or conical shell form a 45-degree included angle; the plurality of rollers B of the omnidirectional load wheel are installed on the outer circumferential surface of the load wheel shell, and the rollers B adopt an omnidirectional wheel type layout, that is, the axis of the roller B is perpendicular to the generatrix of the corresponding cylindrical shell or conical shell. The application can combine the cylindrical McKenna wheel and the conical McKenna wheel, and improve the adaptability of the action device.

Description

Technical Field

[0001] This invention belongs to the field of Mecanum wheel technology, specifically relating to a multi-mode Mecanum motion device for a pipeline robot and a roller design method. Background Technology

[0002] With the development of social productivity, the progress of national industrialization, and the improvement of people's living standards, more and more pipelines are appearing in production and daily life, such as oil and gas pipelines, industrial hydraulic pipelines, sewage pipelines, water supply pipelines, and air conditioning pipelines. As usage time increases, these pipelines may experience blockages, leaks, and aging, requiring suitable maintenance tools. In the event of various emergencies, there is also an urgent need for transport equipment that can navigate through these pipelines. Under these demands, various types of pipeline robots have emerged.

[0003] More mature pipeline robots typically have several (usually 2-4) moving devices arranged radially, as shown in the attached diagram. Figure 1 and Figure 2 As shown, when moving through a circular pipe, a diameter-changing device is used to open each motion device radially outward along the pipe, attaching it to the inner wall of the pipe. The friction of the inner wall propels the robot forward. As the part that contacts the pipe and provides the driving force, the motion device often plays a relatively important role in the entire robot.

[0004] The Mecanum wheel is a special type of wheel invented in 1973 by BentIlon, an engineer at the Swedish company Mecanum. (See attached image.) Figure 3 As shown. This type of wheel consists of a central main wheel and a ring of rollers surrounding it. These rollers can both revolve around the main wheel and rotate around their own axles. The axles of each roller form an angle with the generatrix of the main wheel at the corresponding position, typically 45°. Due to this angle, the Mecanum wheel tends to move parallel to the axle of the main wheel. Through reasonable structural design and control, this tendency can be used to enable vehicles equipped with Mecanum wheels to achieve omnidirectional movement on the ground.

[0005] Mecanum wheels provide omnidirectional ground movement, making them ideal for confined and complex environments, including pipes, and offering significant potential applications in pipeline robotics. Currently, research on the application of Mecanum-type motion devices in robotics, particularly pipeline robots, is highly active both domestically and internationally, yielding some results. For example, a patented prefabricated cabin cleaning and dust removal robot (CN 218610784U, 2023.03.14) utilizes a Mecanum-type drive mechanism. This robot has two Mecanum wheels on each side of its main body, parallel to each other, connected to the main body via axles, and driven by a motor.

[0006] However, current Mecanum-based mobile devices all have some intractable problems:

[0007] 1. Currently, Mecanum wheels in Mecanum-type mobility devices are often designed with a cylindrical outer surface. This structure requires them to be perpendicular to the pipe wall or ground during movement; otherwise, the Mecanum wheel will lose its omnidirectional movement capability and experience accelerated wear. These issues necessitate that pipeline robots using Mecanum-type mobility devices must arrange at least two mobility devices in parallel when moving on ground, while arranging them at an angle when moving through pipes. Switching between these two terrain conditions requires changing the arrangement angles of two or more mobility devices, as shown in the attached diagram. Figure 4 As shown. This type of robot requires an additional mechanism to control the angle of the movement device, resulting in increased size and control difficulty. In addition, due to the unavoidable delay in computer control, the robot's adaptability to changes in pipe diameter will be greatly reduced, making it difficult to meet the needs of actual work or combat.

[0008] 2. Pipeline environments are highly complex, and pipeline robots frequently undergo posture changes during operation, often at significant angles, making them prone to tipping over. Once tipped over, existing Mecanum-based pipeline robots often cannot continue functioning normally, requiring manual removal and redeployment, which presents significant limitations. Summary of the Invention

[0009] In view of this, the present invention provides a multi-mode Mecanum motion device and roller design method for a pipeline robot, which can combine cylindrical Mecanum wheels and conical Mecanum wheels to improve the adaptability of the motion device.

[0010] This invention is achieved through the following technical solution:

[0011] A multi-mode Mecanum motion device for a pipeline robot includes: a support frame and Mecanum drive wheels and omnidirectional load-bearing wheels mounted side-by-side on the support frame; the axes of the Mecanum drive wheels and the omnidirectional load-bearing wheels are parallel.

[0012] The Mecanum drive wheel includes: a drive wheel axle, a drive wheel housing, and several rollers A;

[0013] The omnidirectional road wheel includes: a road wheel axle, a road wheel housing, and several rollers B;

[0014] Both the drive wheel axle and the load-bearing wheel axle are fixedly connected to the bracket; the drive wheel housing is coaxially mounted on the drive wheel axle via bearings, and the load-bearing wheel housing is coaxially mounted on the drive wheel axle via bearings; the drive wheel axle drives the drive wheel housing to rotate via a motor;

[0015] Both the drive wheel housing and the road wheel housing consist of a central cylindrical housing and conical housings on both sides;

[0016] Several rollers A are mounted on the outer circumference of the drive wheel housing. The rollers A adopt a Mecanum wheel layout, that is, the axis of roller A forms a 45° angle with the generatrix of the corresponding cylindrical or conical housing. The rollers A are arranged in three rings, which correspond to the cylindrical housing in the middle and the conical housing on both sides of the drive wheel housing, forming the cylindrical Mecanum wheel in the middle and the conical Mecanum wheels on both sides.

[0017] Several rollers B are installed on the outer circumference of the load-bearing wheel housing. The rollers B adopt an omnidirectional wheel layout, that is, the axis of roller B is perpendicular to the generatrix of the corresponding cylindrical or conical housing.

[0018] Furthermore, a motor stator is fixed in the middle of the drive wheel shaft, and a motor rotor is fixed on the drive wheel housing; the motor stator and the motor rotor constitute a motor, and when the motor is working, the motor rotor drives the drive wheel housing to rotate around the axis of the drive wheel shaft.

[0019] A design method for a conical Mecanum wheel roller, wherein the conical Mecanum wheel roller is roller A located at the conical outer shell of the drive wheel housing, and the specific steps of the design method are as follows:

[0020] Step 1: Establish a rectangular coordinate system Oxyz with O as the origin. Cone OP is the theoretical design cone of the conical Mecanum wheel. Straight line m is the roller axis. Point C is the point with the maximum radius in contact with the ground. The distance from this point to the cone axis is R, and the value of R is determined by the overall design. The plane coplanar with the roller axis and the roller generatrix is ​​plane α. Curve AB is the roller generatrix. Points D, E, and F are the projections of points A, B, and C onto straight line m, respectively. The lengths of line segments CF, DF, and EF are determined by the overall design. Among them, the length of line segment CF determines the maximum radius of the roller, and the lengths of line segments DF and EF determine the axial length of the roller.

[0021] Therefore, the equation of the lateral surface of the cone OP in the coordinate system Oxyz is:

[0022]

[0023] Step two, taking C as the origin, with The direction is the positive x-axis, with With the direction being the positive y-axis, establish a rectangular coordinate system Cxyz, and transform equation (1-1) from coordinate system Oxyz to coordinate system Cxyz to obtain the equation of the lateral surface of cone OP in coordinate system Cxyz:

[0024] The coordinate transformation equation is obtained from the position of coordinate system Oxyz in coordinate system Cxyz:

[0025]

[0026] Summarized as follows:

[0027]

[0028] Substituting equation (1-3) into equation (1-1), we obtain the equation of the lateral surface of the cone OP in the coordinate system Cxyz:

[0029]

[0030] Step 3, since the equation of plane α in coordinate system Cxyz is:

[0031] Formula for z=0 (1-5)

[0032] Combining equations (1-4) and (1-5), we obtain the equation for curve AB, i.e., the roller generatrix:

[0033]

[0034] The model of the roller can be obtained based on the equation of the roller generatrix.

[0035] A pipeline robot includes: a main body, four moving devices, and four diameter-changing devices; the moving devices are those described above.

[0036] The main body is a cylindrical support structure, and four moving devices are connected to the main body one by one through four diameter-changing devices. The four moving devices are distributed radially at equal angles with the main body as the center. The moving devices are used to provide the driving force to drive the pipeline robot forward, and the diameter-changing devices are used to change the distance between the moving devices and the main body to adapt to pipelines of different diameters.

[0037] Furthermore, the main body is equipped with a variable diameter power device, a variable diameter transmission device, and four ball screws; the variable diameter power device is located in the center of the main body; the variable diameter transmission device is located at the rear end of the main body; and the four ball screws are evenly distributed around the main body; and the axis of the ball screws is parallel to the axis of the main body.

[0038] The variable diameter power unit includes: a servo motor for driving the variable diameter device and a power supply for supplying power to the servo motor; wherein the servo motor is longitudinally arranged along the axis of the main body, and the output shaft faces rearward.

[0039] The variable diameter transmission device is a fixed-axis gear transmission, consisting of a central input gear, four idler gears evenly distributed around the input gear, and four output gears located at the edge and meshing with the four idler gears respectively. The input gear is coaxially connected to the output shaft of the servo motor, and the four output gears are coaxially connected to four ball screws respectively. The four ball screws can be driven by the servo motor through gear transmission. During driving, the movement of each ball screw is completely consistent, and each ball screw corresponds to one variable diameter device.

[0040] Furthermore, the diameter-changing device is a scissor lift frame; the scissor lift frame consists of eight intersecting rods, so that each scissor lift frame has four connecting ends, two at the top and two at the bottom; one connecting end of the lower part of the scissor lift frame is connected to a nut fitted on the ball screw, and the other connecting end of the lower part of the scissor lift frame is connected to the front end of the main body; a quick-release plate is installed on one connecting end of the upper part of the scissor lift frame; a rectangular track is machined on each of the two opposite sides of the quick-release plate, and the length direction of the rectangular track is parallel to that of the ball screw. The axes of the levers are parallel; a quick-release plate pin is installed on the other connecting end of the upper part of the scissor lift frame, and the quick-release plate pin slides in cooperation with the rectangular track on the side of the quick-release plate; when the connecting end of the lower part of the scissor lift frame moves linearly back and forth along the axis of the ball screw with the nut on the ball screw, the quick-release plate pin of the connecting end of the upper part of the scissor lift frame slides synchronously in the rectangular track on the side of the quick-release plate, so as to realize the extension or shortening of the scissor lift frame, thereby realizing the change of distance between the main body and the moving device, and finally realizing the diameter change of the entire pipeline robot;

[0041] The quick-release plate has a T-shaped track on its upper surface. The moving device is equipped with a T-shaped structure that matches the track. When the T-shaped track matches the T-shaped structure and is fixed with bolts, the quick-release plate of the moving device and the variable diameter device are connected.

[0042] Furthermore, when the pipeline robot travels in the pipeline, it uses a diameter-changing device to spread the four motion devices outward along the radial direction of the pipeline and attach them to the inner wall of the pipeline. At this time, the motion devices are perpendicular to the pipe wall, the cylindrical Mecanum wheels contact the pipe wall, and the motion mode is pipeline mode, which can realize omnidirectional travel in the pipeline.

[0043] When the pipeline robot travels on the ground, any two adjacent moving parts will attach to the ground. At this time, the moving parts are at a 45° angle to the ground, the conical Mecanum wheels are in contact with the ground, and the movement mode is ground mode, which can achieve omnidirectional travel on the ground.

[0044] When the pipeline robot is traveling on the ground, if it overturns due to obstacles on the road, the four moving devices are radially distributed at equal angles around the main body. The pipeline robot can still maintain any two adjacent moving devices attached to the ground. It can resume normal operation simply by changing the drive control strategy.

[0045] Beneficial effects:

[0046] (1) This invention provides a multi-mode Mecanum motion device for a pipeline robot. It designs a conical Mecanum wheel and combines it with a traditional cylindrical Mecanum wheel. It has multiple motion modes such as pipeline mode and ground mode. It can achieve omnidirectional movement in both pipeline and ground conditions. It can perform tasks with both conditions well, greatly improving the adaptability and work efficiency of the pipeline robot.

[0047] (2) The present invention provides a design method for a conical Mecanum roller. This design method obtains the roller model by calculating the generatrix equation of the roller. The calculation process of this method is simple, reliable and easy to implement.

[0048] (3) The present invention provides a pipeline robot, wherein the main body of the pipeline robot and the moving device are connected by a diameter changing device. The diameter changing device can change the distance between the moving device and the main body to adapt to pipelines of different diameters and improve the applicability of the pipeline robot.

[0049] (4) The present invention provides a pipeline robot. When the pipeline robot is traveling on the ground, if the pipeline robot overturns due to obstacles on the road, the pipeline robot can still maintain any two adjacent moving devices attached to the ground. It can resume normal operation by simply changing the drive control strategy. This solves the problem that the existing Mecanum-type pipeline robot cannot continue to work normally after overturning, and improves the applicability of the pipeline robot. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of a relatively mature pipeline robot;

[0051] Figure 2 This is a schematic diagram of another, more mature, pipeline robot.

[0052] Figure 3 A schematic diagram of an existing Mecanum wheel structure;

[0053] Figure 4 A diagram illustrating the operation of a robot with angles set up using existing controllable motion devices;

[0054] Figure 5 This is a schematic diagram of the pipeline robot of the present invention;

[0055] Figure 6 This is a schematic diagram of the main body and the diameter changing device of the present invention;

[0056] Figure 7 This is a schematic diagram of the structure of the mobile device of the present invention;

[0057] Figure 8 This is a schematic diagram of the structure of the bracket of the present invention;

[0058] Figure 9 This is a schematic diagram of the Mecanum drive wheel of the present invention;

[0059] Figure 10 This is a schematic diagram of the drive wheel shaft of the present invention;

[0060] Figure 11 This is a schematic diagram of the structure of the drive wheel housing of the present invention;

[0061] Figure 12 This is a schematic diagram of the omnidirectional road wheel of the present invention;

[0062] Figure 13 This is a schematic diagram of the structure of the load-bearing wheel axle of the present invention;

[0063] Figure 14 This is a schematic diagram of the structure of the load-bearing wheel shell of the present invention;

[0064] Figure 15 This is a schematic diagram of the pipeline robot of the present invention moving in a pipeline;

[0065] Figure 16 This is a schematic diagram of the pipeline robot of the present invention moving on the ground;

[0066] Figure 17 This is a schematic diagram of the design of the conical Mecanum roller of the present invention;

[0067] Among them, 1-main body, 2-moving device, 3-diameter changing device, 4-drive wheel axle, 5-drive wheel housing, 6-roller A, 7-load-bearing wheel axle, 8-load-bearing wheel housing, 9-roller B. Detailed Implementation

[0068] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0069] Example 1:

[0070] This embodiment provides a pipeline robot, which has a radial structure. See attached document. Figure 5 It includes: main body 1, four moving devices 2 and four diameter changing devices 3;

[0071] The main body 1 is a cylindrical support structure. The four moving devices 2 are connected to the main body 1 one by one through four diameter changing devices 3. The four moving devices 2 are distributed radially at equal angles with the main body 1 as the center. The moving devices 2 are used to provide the driving force to drive the pipeline robot forward. The diameter changing devices 3 are used to change the distance between the moving devices 2 and the main body 1 to adapt to pipelines of different diameters.

[0072] The main body 1 is equipped with a variable diameter power device, a variable diameter transmission device and four ball screws; the variable diameter power device is located in the center of the main body 1; the variable diameter transmission device is located at the rear end of the main body 1; and the four ball screws are evenly distributed around the main body 1; and the axis of the ball screws is parallel to the axis of the main body 1.

[0073] See appendix Figure 6 The variable diameter power unit includes: a servo motor for driving the variable diameter device 3 and a power supply for supplying power to the servo motor; wherein the servo motor is longitudinally arranged along the axial direction of the main body 1, and the output shaft faces rearward;

[0074] The variable diameter transmission device is a fixed-axis gear transmission, consisting of a central input gear, four idler gears evenly distributed around the input gear, and four output gears located at the edge and meshing with the four idler gears respectively; the input gear is coaxially connected to the output shaft of the servo motor, and the four output gears are coaxially connected to four ball screws respectively; the four ball screws can be driven by the servo motor through gear transmission, and the movement of each ball screw is completely consistent during driving, with each ball screw corresponding to one variable diameter device 3;

[0075] The diameter-changing device 3 is used to connect the main body 1 and the moving device 2 and realize diameter changing. Its main structure is a scissor lift frame. The scissor lift frame consists of eight rods arranged in pairs, so that each scissor lift frame has four connecting ends, two at the top and two at the bottom. One connecting end of the lower part of the scissor lift frame is connected to a nut fitted on the ball screw, and the other connecting end of the lower part of the scissor lift frame is connected to the front end of the main body 1. A quick-release plate is installed on one connecting end of the upper part of the scissor lift frame. A rectangular track is machined on each of the two opposite sides of the quick-release plate, and the length direction of the rectangular track is parallel to the axis of the ball screw. A quick-release plate pin is installed on the other connecting end of the upper part of the scissor lift frame, and the quick-release plate pin slides against the rectangular track on the side of the quick-release plate. Dynamic coordination; when the lower connecting end of the scissor lift reciprocates linearly along the axis of the ball screw with the nut on the ball screw, the quick-release plate pin of the upper connecting end of the scissor lift slides synchronously in the rectangular track on the side of the quick-release plate, realizing the extension or shortening of the scissor lift, thereby realizing the change of distance between the main body 1 and the moving device 2, and finally realizing the diameter change of the entire pipeline robot; specifically: when the servo motor drives the ball screw to move the nut to the front end of the main body 1, the scissor lift extends, the moving device 2 moves away from the main body 1, and the applicable pipe diameter of the pipeline robot increases; when the servo motor drives the ball screw to move the nut to the rear end of the main body 1, the scissor lift lowers, the moving device 2 moves closer to the main body 1, and the applicable pipe diameter of the pipeline robot decreases.

[0076] The quick-release plate has a T-shaped track on its upper surface. The moving device 2 is equipped with a T-shaped structure that matches it. When the T-shaped track matches the T-shaped structure and is fixed with bolts, the quick-release plate of the moving device 2 and the diameter-changing device 3 are connected.

[0077] Example 2:

[0078] This embodiment provides a multi-mode Mecanum motion device for a pipeline robot. The multi-mode Mecanum motion device adopts motion device 2 from Embodiment 1. Motion device 2 is used to drive the pipeline robot's movement. (See attached diagram.) Figure 7 Each motion device 2 includes: a Mecanum drive wheel with a hub motor, an omnidirectional load wheel and a bracket;

[0079] See appendix Figure 8 The bracket has an inverted U-shaped structure, and its top is provided with a T-shaped structure that cooperates with the T-shaped track of the quick-release plate; the Mecanum drive wheel and the omnidirectional load wheel are arranged side by side between the two side plates of the bracket, and the axes of the Mecanum drive wheel and the omnidirectional load wheel are parallel.

[0080] See appendix Figure 9-11 The Mecanum drive wheel, used to provide driving force and bear pressure, includes: a drive wheel shaft 4 located in the center, a drive wheel housing 5 located on the periphery, and several rollers A6. The two ends of the drive wheel shaft 4 are fixedly connected to the bracket, and a motor stator is fixed in the middle of the drive wheel shaft 4. The drive wheel housing 5 is coaxially mounted on the drive wheel shaft 4 through bearings, and a motor rotor is fixed on the drive wheel housing 5. The motor stator and the motor rotor constitute a motor. When the motor is working, the motor rotor drives the drive wheel housing 5 to rotate around the axis of the drive wheel shaft 4 to realize the driving function.

[0081] The drive wheel housing 5 is divided into three parts: a central cylindrical housing and two conical housings on both sides. Several rollers A6 are installed on the outer circumference of the drive wheel housing 5. The rollers A6 adopt a Mecanum wheel layout, that is, the axis of the roller A6 forms a 45° angle with the generatrix of the corresponding cylindrical or conical housing. The rollers A6 are arranged in three circles, which correspond to the central cylindrical housing and the two conical housings on both sides, forming the central cylindrical Mecanum wheel and the two conical Mecanum wheels. The design method of the cylindrical Mecanum wheel is similar to the existing Mecanum wheel design method, while the design method of the conical Mecanum wheel is discussed in detail in Embodiment 3.

[0082] See appendix Figure 12-14 The omnidirectional load-bearing wheel is used to bear pressure and prevent the pipeline robot from tipping over in the forward and backward directions. It includes: a load-bearing wheel axle 7 located in the center, a load-bearing wheel shell 8 located on the periphery, and several rollers B9.

[0083] The two ends of the load-bearing wheel axle 7 are fixedly connected to the bracket, and the load-bearing wheel housing 8 is coaxially mounted on the load-bearing wheel axle 7 through bearings; the load-bearing wheel housing 8 is divided into three parts: a central cylindrical housing and two conical housings on both sides. Several rollers B9 are installed on the outer circumference of the load-bearing wheel housing 8. The rollers B9 are arranged in four circles. The central cylindrical housing has two circles of rollers B9, and the two conical housings on both sides each have one circle of rollers B9. The rollers B9 adopt an omnidirectional wheel layout, that is, the axis of the rollers B9 is perpendicular to the generatrix of the corresponding cylindrical housing or conical housing.

[0084] Therefore, the omnidirectional road wheel and the Mecanum drive wheel have similar structures, but the differences are as follows: there is no motor in the middle of the road wheel axle 7, and the rollers B9 on the outer periphery of the road wheel housing 8 do not adopt the Mecanum wheel layout, but the omnidirectional wheel layout.

[0085] Working principle:

[0086] When the pipeline robot travels in the pipeline, see the appendix. Figure 15 Using the reducing device 3, the four moving devices 2 are opened outward along the radial direction of the pipe and attached to the inner wall of the pipe. At this time, the moving devices 2 are perpendicular to the pipe wall, the cylindrical McNum wheel contacts the pipe wall, and the movement mode is the pipe mode, which can realize omnidirectional travel in the pipe.

[0087] When the pipeline robot travels on the ground, see the appendix. Figure 16 Two adjacent moving devices 2 will attach to the ground. At this time, the moving device 2 is at a 45° angle to the ground, the conical McNum wheel is in contact with the ground, the movement mode is ground mode, and it can achieve omnidirectional travel on the ground.

[0088] When the pipeline robot is traveling on the ground, if it overturns due to obstacles on the road, the four moving devices 2 are distributed radially and at equal angles around the main body 1. The pipeline robot can still maintain two adjacent moving devices 2 attached to the ground. It can resume normal operation simply by changing the drive control strategy.

[0089] Example 3:

[0090] Based on Embodiment 2, this embodiment provides a design method for a conical Mecanum wheel roller. The conical Mecanum wheel roller is roller A6 located at the conical outer shell of the drive wheel housing, hereinafter referred to as the roller. The specific steps of the roller design method are as follows:

[0091] Step 1: Establish a rectangular coordinate system Ox0y0z0 with O as the origin. (See appendix) Figure 17The cone OP is the theoretical design cone of the conical Mecanum wheel. The straight line m is the roller axis. Point C is the point with the maximum radius in contact with the ground. The distance from this point to the cone axis is R, and the value of R is determined by the overall design. The plane coplanar with the roller axis and the roller generatrix is ​​plane α. The curve AB is the roller generatrix. Points D, E, and F are the projections of points A, B, and C onto the straight line m, respectively. The lengths of line segments CF, DF, and EF are determined by the overall design. Among them, the length of line segment CF determines the maximum radius of the roller, and the lengths of line segments DF and EF determine the axial length of the roller.

[0092] Therefore, the equation of the lateral surface of cone OP in coordinate system Ox0y0z0 is:

[0093]

[0094] Step two, taking C as the origin, with The direction is the positive x-axis, with With the direction being the positive y-axis, establish a rectangular coordinate system Cxyz, and transform equation (1-1) from coordinate system Ox0y0z0 to coordinate system Cxyz to obtain the equation of the lateral surface of cone OP in coordinate system Cxyz:

[0095] The coordinate transformation equation is obtained from the position of coordinate system Ox0y0z0 in coordinate system Cxyz:

[0096]

[0097] Summarized as follows:

[0098]

[0099] Substituting equation (1-3) into equation (1-1), we obtain the equation of the lateral surface of the cone OP in the coordinate system Cxyz:

[0100]

[0101] Step 3, since the equation of plane α in coordinate system Cxyz is:

[0102] Formula for z=0 (1-5)

[0103] Combining equations (1-4) and (1-5), we obtain the equation for curve AB, i.e., the roller generatrix:

[0104]

[0105] Therefore, for the Mecanum drive wheel in this embodiment, R = 40.5mm, LDF = LEF = 15mm, substituting into formula (1-6), we can obtain...

[0106]

[0107] The model of the roller is obtained based on the equation of the roller generatrix.

[0108] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method of designing a conical Mecanum wheel roller for a multi-mode Mecanum locomotion device of a pipe robot, characterized in that, The multi-mode Mecanum action device of the pipeline robot comprises a support and Mecanum drive wheels and omnidirectional load wheels arranged side by side on the support; the axes of the Mecanum drive wheels and the omnidirectional load wheels are parallel; The Mecanum drive wheel comprises a drive wheel shaft, a drive wheel shell and a plurality of rollers A; The omnidirectional load wheel comprises a load wheel shaft, a load wheel shell and a plurality of rollers B; The drive wheel shaft and the load wheel shaft are fixedly connected with the support; the drive wheel shell is coaxially sleeved on the drive wheel shaft through a bearing, and the load wheel shell is coaxially sleeved on the load wheel shaft through a bearing; the drive wheel shaft drives the drive wheel shell to rotate through a motor; The drive wheel shell and the load wheel shell each comprise a middle cylindrical shell and two side conical shells; The plurality of rollers A are arranged on the outer circumferential surface of the drive wheel shell, and the rollers A adopt a Mecanum wheel type layout, that is, the axis of the roller A forms a 45° angle with the generatrix of the corresponding cylindrical shell or conical shell; the rollers A are arranged in three circles, and the three circles correspond to the middle cylindrical shell and the two side conical shells of the drive wheel shell respectively, thereby forming a middle cylindrical Mecanum wheel and two side conical Mecanum wheels; The plurality of rollers B are arranged on the outer circumferential surface of the load wheel shell, and the rollers B adopt an omnidirectional wheel type layout, that is, the axis of the roller B is perpendicular to the generatrix of the corresponding cylindrical shell or conical shell; The pipeline robot comprises a main body, four action devices and four variable-diameter devices; The main body is a support in a cylindrical structure, the four action devices are connected with the main body through the four variable-diameter devices one by one respectively; the four action devices are distributed at equal angles in a radial manner with the main body as the center; the action device is used for providing driving force for driving the pipeline robot to move forward, and the variable-diameter device is used for changing the distance between the action device and the main body to adapt to pipelines with different diameters; The specific steps of the design method of the conical Mecanum wheel roller of the multi-mode Mecanum action device for the pipeline robot are as follows: Step one, establishing a rectangular coordinate system Oxyz with O as the origin, the conical OP is the theoretical design conical of the conical Mecanum wheel, the straight line m is the roller axis, the point C is the point with the maximum radius in contact with the ground, the distance from the point C to the conical axis is R, the value of R is determined by the overall design, the plane in which the roller axis and the roller generatrix are coplanar is the plane α, the curve AB is the roller generatrix, the points D, E and F are the projections of the points A, B and C on the straight line m respectively, the lengths of the line segments CF, DF and EF are determined by the overall design, wherein the length of the line segment CF determines the maximum radius of the roller, and the lengths of the line segments DF and EF determine the axial length of the roller; Therefore, the equation of the side of the conical OP in the coordinate system Oxyz is as follows: Formula (1-1) Step two, taking C as the origin, taking the direction of C as the x-axis positive direction, taking the direction of B as the y-axis positive direction, establishing a rectangular coordinate system Cxyz, and transforming formula (1-1) from the coordinate system Oxyz to the coordinate system Cxyz to obtain the equation of the side of the cone OP in the coordinate system Cxyz: The coordinate transformation equation is obtained from the position of the coordinate system Oxyz in the coordinate system Cxyz: Formula (1-2) After arrangement, the equation is as follows: Formula (1-3) The equation of the side of the conical OP in the coordinate system Cxyz is obtained by substituting formula (1-3) into formula (1-1): Formula (1-4) Since the equation of the plane α in the coordinate system Cxyz is as follows: z=0 formula (1-5) The equation of the curve AB, that is, the roller generatrix, is obtained by combining formula (1-4) and formula (1-5): Formula (1-6) According to the equation of the roller generatrix, the model of the roller can be obtained.

2. A method of designing a conical omni-wheel roller for a multi-mode omni-directional mobility device of a pipe robot as claimed in claim 1, characterized in that, The middle part of the driving wheel shaft is fixed with a motor stator, and the driving wheel shell is fixed with a motor rotor; the motor stator and the motor rotor form a motor, and when the motor works, the motor rotor drives the driving wheel shell to rotate around the axis of the driving wheel shaft.

3. A method of designing a conical omni-wheel roller for a multi-mode omni-directional mobility device of a pipe robot as claimed in claim 1, characterized in that, The variable-diameter power device, the variable-diameter transmission device and the four ball screws are mounted on the main body; the variable-diameter power device is located at the center of the main body; the variable-diameter transmission device is located at the rear end of the main body, and the four ball screws are distributed around the main body; and the axis of the ball screw is parallel to the axis of the main body; The variable-diameter power device comprises a rudder for driving the variable-diameter device to work and a power supply for supplying power to the rudder; wherein the rudder is longitudinally arranged along the axis of the main body, and the output shaft faces backward; The variable-diameter transmission device is a fixed shaft gear transmission, which is composed of a central input gear, four idlers evenly distributed around the input gear, and four output gears located at the edge and meshing with the four idlers respectively; the input gear is coaxially connected with the output shaft of the rudder, and the four output gears are coaxially connected with the four ball screws one by one respectively; the four ball screws can be driven by the rudder through gear transmission, and the movement of each ball screw is completely consistent during driving, and each ball screw corresponds to a variable-diameter device.

4. A method of designing a conical omni-wheel roller for a multi-mode omni-directional mobility device of a pipe robot as claimed in claim 3, characterized in that, The variable-diameter device is a scissor type lifting frame; the scissor type lifting frame is composed of eight rods that are crossed in pairs, so that each scissor type lifting frame has four connection ends, two upper and two lower; one of the lower connection ends of the scissor type lifting frame is connected with a nut sleeved on the ball screw, and the other lower connection end of the scissor type lifting frame is connected with the front end of the main body; one of the upper connection ends of the scissor type lifting frame is provided with a quick release plate; two opposite sides of the quick release plate are each provided with a rectangular track, and the length direction of the rectangular track is parallel to the axis of the ball screw; the other upper connection end of the scissor type lifting frame is provided with a quick release plate pin, and the quick release plate pin is in sliding fit with the rectangular track on the side of the quick release plate; when the lower connection end of the scissor type lifting frame moves linearly along the axis of the ball screw with the nut on the ball screw, the quick release plate pin of the upper connection end of the scissor type lifting frame slides synchronously in the rectangular track on the side of the quick release plate, so as to realize the elongation or shortening of the scissor type lifting frame, and further realize the change of the distance between the main body and the movement device, and finally realize the variable-diameter of the whole pipeline robot; The upper surface of the quick release plate is provided with a T-shaped track in cross section, and the movement device is provided with a T-shaped structure matched therewith; when the T-shaped track is matched with the T-shaped structure and fixed by using a bolt, the connection between the movement device and the quick release plate of the variable-diameter device is realized.

5. A method of designing a conical omni-wheel roller for a multi-mode omni-directional mobility device of a pipe robot as claimed in claim 1, characterized in that, When the pipeline robot travels in the pipeline, the variable-diameter device is used to open the four movement devices outward along the radial direction of the pipeline, and the movement devices are attached to the inner wall of the pipeline; at this time, the movement devices are perpendicular to the pipe wall, the cylindrical Mecanum wheel contacts the pipe wall, the movement mode is the pipeline mode, and omnidirectional travel in the pipeline can be realized; When the pipeline robot travels on the ground, any two adjacent movement devices will be attached to the ground; at this time, the movement device and the ground form a 45° angle, the conical Mecanum wheel contacts the ground, the movement mode is the ground mode, and omnidirectional travel on the ground can be realized. In the pipeline robot, when the pipeline robot runs on the ground, if the pipeline robot overturns due to obstacles on the ground, since the four movement devices are distributed at equal angles around the main body in a radial manner, the pipeline robot can still keep the state that any two adjacent movement devices are attached to the ground, and only the driving control strategy needs to be replaced, so that the normal work can be restored.

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