Redundant drive parallel wall-climbing robot for grinding surface of large structural member

Abstract

The invention relates to the field of industrial robot machining. The invention aims to provide the redundant drive parallel wall-climbing robot for grinding the surface of the large structural member so as to solve the problems of difficult machining operation and insufficient machining precision caused by complex actual machining scene. According to the technical scheme, the invention discloses a redundant drive parallel wall-climbing robot for grinding the surface of a large structural member. The six-degree-of-freedom parallel robot is characterized in that a six-degree-of-freedom parallel mechanism is arranged between the fixed platform and the movable platform; the six-degree-of-freedom parallel mechanism comprises four first branches which are connected in parallel. Each first branch comprises a first moving pair, a hooke joint, a second moving pair and a spherical hinge which are sequentially connected between the fixed platform and the movable platform; the movable platform is provided with a movable platform magnetic adsorption mechanism so that the stability of the movable platform can be improved when large complex parts are machined. A fixed platform negative pressure adsorption mechanism is arranged at the bottom end of the fixed platform so that adaptive adsorption can be conducted according to the surface shape of the large complex part during moving and machining.

Description

Technical Field

[0001] This invention relates to the field of industrial robot processing, specifically to a redundant drive parallel wall-climbing robot for surface grinding of large structural parts. Background Technology

[0002] With the continuous advancement of my country's industrial technology, especially in the automotive, shipbuilding, and aerospace fields, the demand for machining large and complex parts is increasing. These parts typically have complex curved surface structures and unique machining environments. Traditional machining methods often fail to effectively meet the demand for high-precision machining due to their large size, difficulty in guaranteeing accuracy, and complexity in installation and repositioning. Existing machining methods for large and complex parts, such as envelope machining based on large gantry milling machines, are also unsuitable for achieving high-precision machining in complex machining scenarios due to the large structure of the machining equipment, the difficulty in installation and repositioning, and the relatively low machining accuracy.

[0003] Compared to serial mechanisms, parallel mechanisms offer advantages such as higher load-bearing capacity, higher stiffness, and superior dynamic performance, making parallel robots more promising for modern high-precision machining. However, traditional parallel robots are typically limited by fixed frames, which means they still face structural and adaptability challenges when dealing with large-scale, high-precision machining tasks.

[0004] Wall-climbing robots, as special-purpose robots, are widely used in construction, cleaning, and maintenance fields due to their ability to move freely in complex environments, exhibiting strong adaptability and operational flexibility. They effectively solve problems such as high intensity, low efficiency, and inherent dangers of manual labor. However, how to apply wall-climbing robots to the processing of large and complex parts remains an urgent issue to be addressed. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings in the above-mentioned background technology and provide a redundant driven parallel wall-climbing robot for surface grinding of large structural parts, so as to solve the problems of difficult processing operations and insufficient processing accuracy caused by the complexity of actual processing scenarios.

[0006] The technical solution provided by this invention is: A redundant-drive parallel wall-climbing robot for surface grinding of large structural components includes a fixed platform and a moving platform equipped with a spindle machining head. Its key feature is that a six-degree-of-freedom parallel mechanism is provided between the fixed platform and the moving platform. The six-degree-of-freedom parallel mechanism includes four first branches connected in parallel. Each first branch includes a first sliding joint, a Hooke's joint, a second sliding joint, and a ball joint sequentially connected between the fixed platform and the moving platform. The moving platform is equipped with a magnetic adsorption mechanism to improve its stability when machining large and complex parts. The bottom end of the fixed platform is equipped with a negative pressure adsorption mechanism to adaptively adsorb large and complex parts based on their surface shape during movement and machining.

[0007] The moving platform magnetic adsorption mechanism includes several third moving pairs vertically arranged on the moving platform and several magnetic suction cups arranged at the bottom of each third moving pair; the fixed platform negative pressure adsorption mechanism includes several negative pressure suction cups connected to the bottom of the fixed platform through several fourth moving pairs.

[0008] The spindle machining head is rotatably positioned at the bottom of the center of the moving platform with its axis arranged vertically, and the grinding tool is installed at the bottom of the spindle machining head; several vertically arranged third moving pairs are evenly distributed around the spindle machining head, and each third moving pair is provided with a magnetic chuck at its bottom.

[0009] The fixed platform includes an inner ring, several supporting components, and several crossbars. The supporting components are arranged radially around the inner ring, and each supporting component is arranged at an angle from top to bottom. One end of the supporting component is fixed to the inner ring, and the other end is connected and fixed to the adjacent supporting component through the crossbars.

[0010] The first movable pair includes a first movable pair guide rail connected to the fixed platform and a first movable pair slider that slides with the first movable pair guide rail and is connected to a Hooke's joint; the second movable pair includes a second movable pair slide rod connected to the Hooke's joint and a second movable pair sleeve that slides with the second movable pair slide rod and is connected to a ball joint; the third movable pair includes a third movable pair sleeve vertically disposed at the opening of the moving platform and a third movable pair slide rod vertically movable and positioned in the third movable pair sleeve; the fourth movable pair includes a fixed base fixed to the bottom of the support member, a nut rotatably positioned in the fixed base, and a lead screw vertically arranged and engaged with the nut; the bottom end of the lead screw is connected to the negative pressure suction cup.

[0011] Each of the first moving sub-rails is correspondingly disposed on the lower side of the support member and parallel to the support member.

[0012] The supporting member is a channel steel with the opening facing downwards. The lead screw in the ball screw mechanism is rotatably positioned in the groove of the channel steel through a bearing seat, and the lead screw nut is connected to the slider of the first moving pair.

[0013] The first, second, and fourth moving pairs are all drive pairs; and the drive pairs are all motor-driven ball screw mechanisms.

[0014] All motors are connected to an external controller.

[0015] The motor of the first moving pair is mounted on the bottom of the support member, the motor of the second moving pair is mounted on the sleeve, and the motor of the fourth moving pair is mounted on the side of the bottom of the fixed base.

[0016] The beneficial effects of this invention are: The overall structure of this invention features a compact layout, convenient installation and maintenance, low manufacturing cost, and high operational stability. Compared with existing wall-climbing robot structures, it has better engineering applicability and development prospects. In wall-mounted operation scenarios, this invention can achieve coordinated large-scale stable climbing and local fine-tuning operations, and has advantages such as strong adsorption capacity, high overall rigidity, and strong environmental adaptability. In addition, the structure of this invention has fewer actuators, a simplified linkage configuration, and high motion and positioning accuracy, effectively solving the problems of difficult processing operations and insufficient processing accuracy caused by the complexity of actual processing scenarios. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural schematic diagram of an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the actual operation of an embodiment of the present invention.

[0019] Figure 3 yes Figure 1 A three-dimensional structural diagram of the fixed platform.

[0020] Figure 4 yes Figure 1 A three-dimensional structural diagram of the fourth sliding joint in the model.

[0021] Figure 5 yes Figure 1 A three-dimensional structural diagram of the moving platform.

[0022] Figure 6 yes Figure 1 A three-dimensional structural diagram of the first branch in the diagram.

[0023] Figure label: Redundant Driven Parallel Wall-Climbing Robot 1. Large and Complex Parts 2. Fixed Platform 11. Fixed Platform Negative Pressure Adsorption Mechanism 12. Moving Platform 13. Moving Platform Magnetic Adsorption Mechanism 14. Spindle Machining Head 15. Six-Degree-of-Freedom Parallel Mechanism 16. First Moving Pair Guide Rail 111. Fixed End 112. Support Component 113. Inner Ring 114. Fixed Base 121. Lead Screw 122. Second Motor 123. Negative Pressure Suction Cup 124. Ball Joint Support 131. Third Moving Pair Sleeve 132. Magnetic Suction Cup 141. Third Moving Pair Slide Rod 142. Baffle 143. First Moving Pair Slider 161. Hooke Joint 162. Second Moving Pair Slide Rod 163. Second Moving Pair Sleeve 164. Ball Joint 165. Detailed Implementation

[0024] The present invention will now be described in detail with reference to specific embodiments.

[0025] like Figure 1 As shown: A redundantly driven parallel wall-climbing robot 1 for surface grinding of large structural components includes a fixed platform 11, a moving platform 13, and a six-degree-of-freedom parallel mechanism 16. The six-degree-of-freedom parallel mechanism 16 is disposed between the fixed platform and the moving platform. The six-degree-of-freedom parallel mechanism 16 includes four first branches connected in parallel between the fixed platform and the moving platform.

[0026] like Figure 3 As shown: The fixed platform includes four support members 113, an inner ring 114, and four crossbars. The inner ring is the center and highest point of the fixed platform. The four support members are arranged radially around the inner ring, and each support member is arranged at an angle from top to bottom. One end (highest point) of each support member is fixed to the inner ring, and the other end (lowest point) of each pair of adjacent support members is fixed by the crossbars to ensure the stability of the fixed platform 11 during movement. A fixed platform negative pressure adsorption mechanism 12 is provided at the lowest point of each support member. The fixed platform negative pressure adsorption mechanism 12 is located at the bottom of the four support members so that it can adaptively adsorb the surface shape of large and complex parts 2 during robot movement and processing.

[0027] like Figure 4 As shown: The fixed platform negative pressure adsorption mechanism 12 includes four fourth moving joints and four negative pressure suction cups 124; each fourth moving joint includes a fixed base 121 fixed to the bottom of the support member, a nut rotatably positioned in the fixed base, and a vertically arranged lead screw 122 that cooperates with the nut; a second motor 123 is fixed on the fixed base and drives the nut through gears; the surface of the lead screw has a groove parallel to the generatrix, and an anti-rotation block with one end embedded in the groove is installed on the fixed base, thereby forcing the lead screw to move only vertically and not rotate (this anti-rotation structure is prior art). The bottom end of the lead screw is connected to the negative pressure suction cup 124 (conventional structure).

[0028] like Figure 5 As shown: The moving platform 13 is equipped with a spindle machining head 15 and a moving platform magnetic adsorption mechanism 14, which can be used for grinding large and complex parts 2. The spindle machining head 15 is vertically arranged and rotatably positioned at the lower end of the center of the moving platform 13 (the motor and gear transmission mechanism driving the spindle machining head are installed in the center of the moving platform; this structure is prior art; it is omitted in the figure). Grinding tools (such as grinding wheels, grinding steel wool, etc.) are installed at the bottom of the spindle machining head. The moving platform magnetic adsorption mechanism 14 is evenly distributed around the spindle machining head. The moving platform magnetic adsorption mechanism 14 includes four third moving pairs vertically arranged on the moving platform and a magnetic suction cup 141 arranged at the lower end of each third moving pair. The system includes a third movable auxiliary sleeve 132 vertically positioned at the opening of the moving platform 1, and a third movable auxiliary slide rod 142 vertically movable within the sleeve. A baffle 143 is provided at the top of the third movable auxiliary slide rod 142. When the moving platform moves upward, the baffle is pushed by the third movable auxiliary sleeve, thereby pulling the third movable auxiliary slide rod upward. This allows the magnetic suction cup at the bottom of the third movable auxiliary slide rod to detach from the surface of large, complex parts, while ensuring that the third movable auxiliary slide rod 142 remains in sliding engagement with the sleeve. The figure shows that the axes of the four third movable auxiliary slide rods 142 are parallel to each other; the bottom ends of the four third movable auxiliary slide rods are connected to four magnetic suction cups 141 (conventional structure).

[0029] like Figure 6 As shown: The first branch includes a first sliding joint, a Hooke's joint 162, a second sliding joint, and a ball joint 165 sequentially connected between the fixed platform 11 and the moving platform 13. The first sliding joint includes a first sliding joint guide rail 111 connected to the fixed platform 11 and a first sliding joint slider 161 connected to the Hooke's joint 162 and slidably engaged with the first sliding joint guide rail 111; the second sliding joint includes a second sliding joint slide rod 163 connected to the Hooke's joint 162 and a second sliding joint sleeve 164 slidably engaged with the second sliding joint slide rod 163; the end of the second sliding joint sleeve 164 facing away from the Hooke's joint is connected to the ball joint 165.

[0030] Four first movable auxiliary guide rails 111 are respectively set on four support members. Both ends of each first movable auxiliary guide rail 111 are installed on the lower side of the support member through fixed ends 112 and are arranged parallel to the support member. One end of the first movable auxiliary guide rail is close to the center (inner ring) of the fixed platform 11, and the other end is close to the negative pressure adsorption mechanism 12 of the fixed platform. Each first movable auxiliary guide rail is equipped with a slider.

[0031] Each first moving pair is driven by a ball screw driven by a motor; the supporting member is a channel steel with the opening facing downwards, and the screw in the ball screw mechanism is rotatably positioned in the groove of the channel steel through a bearing seat. The screw nut that cooperates with the screw is connected to the slider 161 of the first moving pair; the motor of the first moving pair (omitted in the figure) drives the screw through a gear set, which can drive the slider of the first moving pair to move on the guide rail of the first moving pair.

[0032] The first, second, and fourth sliding joints are all drive joints. Each of these three sliding joints is a ball screw mechanism driven by a motor (omitted in the figure). The motor of the first sliding joint is installed inside the fixed platform 11, the motor of the second sliding joint is installed on a disc near the Hooke joint 162, and the motor of the fourth sliding joint is installed on the side of the bottom of the fixed base 121. When the drive joints move, the six-degree-of-freedom parallel mechanism 16 can output six degrees of freedom motion, including three rotational degrees of freedom and three translational degrees of freedom.

[0033] The negative pressure suction cup 124 is connected to an external air source (preferably a negative pressure air pump). The bottom of the magnetic suction cup 141 is a permanent magnet. The motors of the first, second, and fourth moving parts are connected to an external controller.

[0034] The working principle is (see) Figure 2 When the redundant-drive parallel wall-climbing robot 1 is in operation and attached to the surface of a large, complex part 2 (the surface includes the outer surface, sides, and inner walls of the large, complex part, and other machinable areas), the robot moves under the command of an external controller. During this process, the first and second prismatic joints of the six-degree-of-freedom parallel mechanism work together, with the stationary platform and the moving platform alternately supporting the robot. The stationary platform's negative pressure adsorption mechanism 12 and the moving platform's magnetic adsorption mechanism 14 achieve alternating adsorption under the influence of an external air source and magnetic force, thereby completing the positioning and crawling motion in the machining scenario. The four stationary platform negative pressure adsorption mechanisms 12 can be connected to or disconnected from the air source to meet the robot's adsorption and movement requirements under different working conditions, ensuring the smooth movement of the redundant-drive parallel wall-climbing robot on the machining surface.

[0035] Because the movable joints of the six-degree-of-freedom parallel mechanism 16 adopt a combination of Hooke's joints and ball joints, the mechanism possesses high mobility and stress adaptability while ensuring load-bearing capacity. When the redundant-drive parallel wall-climbing robot moves to the processing area, the fixed platform negative pressure adsorption mechanism 12 and the moving platform magnetic adsorption mechanism 14 simultaneously adsorb onto the surface of the large, complex part 2, firmly fixing the robot to the processing area and significantly improving overall stability, thereby effectively reducing vibration and errors during processing. Subsequently, guided by the third locating joint, the moving platform drives the spindle machining head 15 to descend along the normal direction of the processing area, achieving small-area, high-precision grinding. During processing, if abnormal conditions or processing deviations occur, the controller can immediately control the redundant-drive parallel wall-climbing robot to perform emergency braking; if necessary, manual intervention can also be used to stop processing in advance to ensure the safety of the equipment and the workpiece.

[0036] This invention offers significant advantages in the surface grinding of large and complex parts. By alternating the adsorption methods of the fixed platform negative pressure adsorption mechanism 12 and the moving platform magnetic adsorption mechanism 14, stable positioning and high-precision grinding can be achieved in processing environments with irregular surface shapes and limited space. This effectively reduces the high safety risks, high operational difficulty, and difficulty in controlling processing errors that exist in manual grinding, and better meets the needs of modern industry for automated and high-precision processing.

[0037] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A redundantly driven parallel wall-climbing robot for surface grinding of large structural components, comprising a fixed platform (11) and a moving platform (13) equipped with a spindle machining head (15); characterized in that: The fixed platform and the moving platform are connected in parallel by four first branches; each first branch includes a first sliding joint, a Hooke joint (162), a second sliding joint and a ball joint (165) connected in sequence between the fixed platform and the moving platform; the moving platform is provided with a moving platform magnetic adsorption mechanism (14) to improve the stability of the moving platform when processing large and complex parts (2); the bottom end of the fixed platform is provided with a fixed platform negative pressure adsorption mechanism (12) to adapt to the surface shape of large and complex parts during movement and processing.

2. The redundant drive parallel wall-climbing robot for surface grinding of large structural components according to claim 1, characterized in that: The moving platform magnetic adsorption mechanism (14) includes several third moving pairs vertically arranged on the moving platform and several magnetic suction cups (141) arranged at the bottom of each third moving pair; the fixed platform negative pressure adsorption mechanism (12) includes several negative pressure suction cups (124) connected to the bottom of the fixed platform through several fourth moving pairs.

3. The redundant drive parallel wall-climbing robot for surface grinding of large structural components according to claim 2, characterized in that: The spindle machining head 15 is rotatable and positioned at the bottom of the center of the moving platform 13 with its axis arranged vertically. The grinding tool is installed on the spindle machining head. Several vertically arranged third moving pairs are evenly distributed around the spindle machining head, and each third moving pair is provided with the magnetic chuck (141) at its bottom.

4. The redundant drive parallel wall-climbing robot for surface grinding of large structural components according to claim 3, characterized in that: The fixed platform includes an inner ring (114), several support members (113), and several crossbars. The support members are arranged radially around the inner ring and each support member is arranged at an angle from top to bottom. One end of the support member is fixed to the inner ring, and the other end is connected and fixed to the adjacent support member through the crossbars.

5. The redundant drive parallel wall-climbing robot for surface grinding of large structural components according to claim 4, characterized in that: The first movable pair includes a first movable pair guide rail (111) connected to the fixed platform (11) and a first movable pair slider (161) slidably engaged with the first movable pair guide rail (111) and connected to the Hooke joint (162); the second movable pair includes a second movable pair slide rod (163) connected to the Hooke joint (162) and a second movable pair sleeve (164) slidably engaged with the second movable pair slide rod (163) and connected to the ball joint (165); the third movable pair includes a third movable pair sleeve (132) vertically disposed at the opening of the moving platform (13) and a third movable pair slide rod (142) vertically movable and positioned in the third movable pair sleeve; the fourth movable pair includes a fixed base (121) fixed at the bottom of the support member, a nut rotatably positioned in the fixed base and a lead screw (122) vertically arranged and engaged with the nut; the bottom end of the lead screw is connected to the negative pressure suction cup (124).

6. The redundant drive parallel wall-climbing robot for surface grinding of large structural components according to claim 5, characterized in that: Each of the first moving sub-rails (111) is correspondingly disposed on the lower side of the support member (113) and parallel to the support member.

7. The redundant drive parallel wall-climbing robot for surface grinding of large structural components according to claim 6, characterized in that: The supporting member is a channel steel with the opening facing downwards. The screw in the ball screw mechanism is rotatably positioned in the groove of the channel steel through the bearing seat. The screw nut is connected to the first moving pair slider (161).

8. The redundant drive parallel wall-climbing robot for surface grinding of large structural components according to claim 7, characterized in that: The first, second, and fourth moving pairs are all drive pairs; and the drive pairs are all motor-driven ball screw mechanisms.

9. The redundant drive parallel wall-climbing robot for surface grinding of large structural components according to claim 8, characterized in that: All motors are connected to an external controller.

10. The redundant drive parallel wall-climbing robot for surface grinding of large structural components according to claim 9, characterized in that: The motor and ball screw module of the first moving pair are installed inside the fixed platform (11); the motor of the second moving pair is installed on the disk position near the Hooke hinge (162); the motor of the fourth moving pair is installed on the side of the bottom of the fixed base (121).

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