Parallel robot assembly system based on visual guidance

Abstract

The utility model provides a parallel robot assembly system based on visual guidance, which comprises a profile frame, a mobile platform, a fixed platform and a visual information acquisition mechanism, a first bearing mechanism is fixedly mounted on the mobile platform, and a first workpiece to be assembled is detachably and fixedly mounted on the first bearing mechanism; a second bearing mechanism is fixedly mounted on the fixed platform, and a second to-be-assembled workpiece is detachably and fixedly mounted on the second bearing mechanism; the visual information collecting mechanism is installed on the profile frame and used for collecting position information of the first to-be-assembled workpiece relative to the second to-be-assembled workpiece, and the moving platform moves according to the position information so that the end face of the first to-be-assembled workpiece can coincide with the end face of the second to-be-assembled workpiece. The automatic assembling device can improve assembling precision and efficiency, improve product quality and consistency, meet complex and changeable production requirements, can achieve high-precision automatic assembling of large workpieces, and has the advantages of being simple in structure, convenient to operate, low in cost, low in safety risk and the like.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the automation and intelligent manufacturing technical field, concretely relates to a parallel robot assembly system based on visual guidance. BACKGROUND

[0002] The assembly of large workpieces is an extremely important link in the manufacturing industry. In the aerospace, marine ship equipment and automobile industries, the assembly of large workpieces is very complex and time-consuming, and the labor efficiency is difficult to significantly improve. Moreover, the operator needs to maintain high concentration when performing the assembly work to ensure the accuracy of the workpiece assembly. In addition, during the assembly of large workpieces, the operator generally faces problems such as complex assembly work environment and narrow assembly space, which causes the operator to face long-term high-intensity operation requirements to be able to realize real-time accurate control and adjustment of the workpiece.

[0003] In recent years, the robot industry supported by technology has achieved unprecedented development. Robot technology is increasingly closely linked to human society's production, constantly shaping people's new work and life styles. In the manufacturing industry, robot technology is also widely used, not only ensuring the efficiency of industrial production, but also reducing the cost of industrial production activities to a certain extent, reducing labor intensity and improving economic efficiency. The high flexibility and accuracy of robot technology enable it to perform high-intensity work in various aspects of production and manufacturing, greatly reducing human operational errors in the production process and improving the standardization of assembly work. Compared with traditional manual assembly, robot autonomous assembly can not only quickly and accurately complete the assembly of large and complex workpieces, but also greatly improve assembly efficiency. There is a certain degree of safety risk in the assembly of large workpieces, and engineering accidents caused by work errors of assembly workers are common, and the use of robots can effectively overcome human errors, effectively reduce the risk of worker injury, and improve the safety of the work environment. Therefore, the utility model provides a parallel robot assembly system based on visual guidance to solve the above problems UTILITY MODEL CONTENTS

[0004] The utility model aims at the deficiencies of the prior art, and provides a parallel robot assembly system based on visual guidance, which combines robot technology with the assembly of large workpieces, and has important practical significance.

[0005] In order to achieve the above technical purpose, the utility model adopts the following technical scheme:

[0006] The utility model provides a kind of parallel robot assembly system based on visual guidance, including sectional material frame, mobile platform, fixed platform and visual information acquisition mechanism;The mobile platform is six degrees of freedom mobile platform, and first bearing mechanism is fixedly installed on mobile platform, and first bearing mechanism is detachably fixedly installed with first workpiece to be assembled on it;Second bearing mechanism is fixedly installed on the fixed platform, and second bearing mechanism is detachably fixedly installed with second workpiece to be assembled on it;Visual information acquisition mechanism is installed on sectional material frame, and visual information acquisition mechanism is distributed above first workpiece to be assembled and second workpiece to be assembled, for collecting the position information of first workpiece to be assembled relative to second workpiece to be assembled, and the mobile platform can be moved according to position information, so that the end surface of first workpiece to be assembled and second workpiece to be assembled coincides.

[0007] Further, the first bearing mechanism is provided with a moving end target, and the second bearing mechanism is provided with a fixed end target;The moving end target and the fixed end target are the same structure, and both include target base and target ball, and the target ball is fixedly installed on the target base.

[0008] Further, the first bearing mechanism includes support and first docking seat, the support is fixed on the mobile platform, including two groups of parallel lower support rods, and the end of two groups of lower support rods is connected by connecting rod, to form door-shaped structure;At least one group of upper support rods is fixed on door-shaped structure, and the first docking seat is fixedly installed on the upper support rod;The second bearing mechanism includes second docking seat, and the second docking seat is fixed on the fixed platform, and the second docking seat and the first docking seat are respectively provided with connecting flange for fixing workpiece to be assembled.

[0009] Further, the first bearing mechanism includes support frame and two groups of mounting seats, the support frame is fixed on the mobile platform, and two groups of mounting seats are parallel to each other and are respectively fixed on both ends of the support frame, and both ends of the first workpiece to be assembled are fixedly connected with two groups of mounting seats;The second bearing mechanism includes two groups of mounting seats, and two groups of mounting seats are parallel to each other and are fixed on the fixed platform, and both ends of the second workpiece to be assembled are fixedly connected with two groups of mounting seats.

[0010] Further, the mounting seat of the first bearing mechanism and the second bearing mechanism is the same structure, the mounting seat is provided with circular through hole, and ring plate is detachably fixedly installed in the circular through hole, the workpiece to be assembled is fixed in the center hole of the ring plate, and the inner end face of the ring plate is provided with buffer layer.

[0011] Further, the visual information acquisition mechanism comprises a long light axis, two groups of X-axis connectors, two groups of short light axes, two groups of camera connectors and two groups of binocular vision camera modules; the long light axis is horizontally arranged and fixedly connected with the profile frame through profile connectors at both ends; the X-axis connectors are slidingly installed on the long light axis, the two groups of short light axes are fixedly connected with the two groups of X-axis connectors, the two groups of camera connectors are fixedly connected with the two groups of short light axes, and the camera connectors are distributed above the X-axis connectors; and the two groups of binocular vision camera modules are fixedly installed on the two groups of camera connectors.

[0012] Further, the visual information acquisition mechanism further comprises two groups of light supplement apertures, the two groups of light supplement apertures are fixedly connected with the two groups of short light axes through aperture connectors, and the light supplement apertures are distributed below the binocular vision camera modules.

[0013] Further, the visual information acquisition mechanism comprises a camera, an L-shaped fixing plate, a driving motor, a horizontal rod, a drag chain and a drag chain slot; the horizontal rod and the drag chain slot are fixed on the profile frame, and the L-shaped fixing plate is slidingly connected with the horizontal rod; the output end of the driving motor is drivingly connected with the L-shaped fixing plate, so that the L-shaped fixing plate can be driven to slide along the horizontal rod; one end of the drag chain slot is fixed in the drag chain slot, and the other end is fixedly connected with the L-shaped fixing plate; and the camera is fixedly installed on the L-shaped fixing plate.

[0014] Further, the mobile platform comprises a static plane, a dynamic plane and six groups of leg structures which are the same in structure; the upper and lower ends of the leg structure are movably connected with the static plane and the dynamic plane respectively; the leg structure comprises a servo motor and an electric cylinder, the electric cylinder is hingedly connected with the dynamic plane through an upper end hooke joint, and the electric cylinder is hingedly connected with the static plane through a lower end hooke joint; and the servo motor is fixed on the electric cylinder through a mounting piece to control the extension and contraction of the electric cylinder.

[0015] Further, the mobile platform is arranged inside the profile frame, and the fixed platform is arranged outside the profile frame.

[0016] The utility model discloses the beneficial effect:

[0017] (1) the utility model sets up mobile platform, fixed platform and visual information acquisition mechanism, gathers the position information of first to be assembled workpiece relative to second to be assembled workpiece through visual information acquisition mechanism, and mobile platform moves according to position information, makes the end face of first to be assembled workpiece and second to be assembled workpiece coincide, realizes the accurate efficient assembly of workpiece;

[0018] (2) the utility model overcomes the defects and deficiencies of prior art in mechanical precision and visual identification accuracy, can improve assembly accuracy and efficiency, improves product quality and consistency, adapts to complex and changeable production demand;

[0019] (3) The utility model overcome the precision is difficult to guarantee, the labour efficiency is not high and has the defect of security risk when manual assembly large work piece, can realize high accuracy automation assembly of large work piece;

[0020] (4) The utility model simple structure, convenient operation has low cost, security risk low and so on advantage. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is the structure schematic diagram of the utility model embodiment 2;

[0022] Figure 2 It is the structure schematic diagram of the utility model embodiment 3;

[0023] Figure 3 It is the structure schematic diagram of the utility model mobile platform;

[0024] Figure 4 It is the structure schematic diagram of the utility model supporting leg structure;

[0025] Figure 5 It is the structure schematic diagram of the first bearing mechanism of the utility model embodiment 2;

[0026] Figure 6 It is the structure schematic diagram of the utility model mobile end target / fixed end target;

[0027] Figure 7 It is the structure schematic diagram of the vision information acquisition mechanism of the utility model embodiment 2;

[0028] Figure 8 It is the structure schematic diagram of the vision information acquisition mechanism of the utility model embodiment 3;

[0029] The mark in the drawing is:

[0030] 1, profile frame;2, mobile platform;2-1, static plane;2-2, dynamic plane;2-3, lower end hooke joint;2-4, servo motor;2-5, electric cylinder;2-6, upper end hooke joint;3, fixed platform;4, mobile end target;5, fixed end target;6, support;7, first docking seat;8, long optical axis;9, X-axis connecting piece;10, short optical axis;11, camera connecting piece;12, binocular vision camera module;13, profile connecting piece;14, light filling diaphragm;15, diaphragm connecting piece;16, camera;17, L-shaped fixed plate;18, driving motor;19, cross bar;20, tow chain;21, tow chain slot. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme of the embodiments of the utility model will be described clearly and completely in combination with the drawings in the embodiments of the utility model below. Obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the utility model.

[0032] Embodiment 1

[0033] The utility model embodiment provides a kind of visual guidance-based parallel robot assembly system, including section bar frame 1, mobile platform 2, fixed platform 3 and visual information acquisition mechanism, mobile platform 2 is arranged in section bar frame 1 inside, fixed platform 3 is arranged in section bar frame 1 outside.

[0034] Specifically, with reference to Figures 1-8 The mobile platform 2 is a six-degree-of-freedom mobile platform, and a first bearing mechanism is fixedly installed on the mobile platform 2. A first workpiece to be assembled is detachably and fixedly installed on the first bearing mechanism. A second bearing mechanism is fixedly installed on the fixed platform 3, and a second workpiece to be assembled is detachably and fixedly installed on the second bearing mechanism. The visual information acquisition mechanism is installed on the section bar frame 1, and is distributed above the first workpiece to be assembled and the second workpiece to be assembled, for acquiring position information of the first workpiece to be assembled relative to the second workpiece to be assembled.

[0035] In this embodiment, a mobile end target 4 is arranged on the first bearing mechanism, and a fixed end target 5 is arranged on the second bearing mechanism. The mobile end target 4 and the fixed end target 5 are the same in structure, and each includes a target base and a target ball. The target ball is fixedly installed on the target base.

[0036] In application, the visual information acquisition mechanism is used to acquire the position information of the first workpiece to be assembled relative to the second workpiece to be assembled. The mobile platform 2 can move according to the position information, so that the end faces of the first workpiece to be assembled and the second workpiece to be assembled coincide, and precise and efficient assembly of the workpieces is realized.

[0037] Embodiment 2

[0038] The main structure of this embodiment is the same as that of Embodiment 1, and the difference lies in that the first bearing mechanism and the second bearing mechanism are further described in this embodiment.

[0039] Specifically, with reference to Figure 5, the first bearing mechanism comprises a support frame 6 and a first docking seat 7, the support frame 6 is fixed on the moving platform 2, comprising two groups of parallel lower support rods, the ends of the two groups of lower support rods are connected through connecting rods to form a door-shaped structure; at least one group of upper support rods is fixed on the door-shaped structure, the first docking seat 7 is fixedly installed on the upper support rod; the second bearing mechanism comprises a second docking seat, the second docking seat is fixed on the fixed platform 3, and the second docking seat and the first docking seat 7 are respectively provided with a connecting flange for fixing the workpiece to be assembled.

[0040] In application, two workpieces to be assembled are respectively fixed and installed on the second docking seat and the first docking seat through the connecting flanges, so that the workpieces to be assembled are stably supported, and alignment and assembly operations in the next step are facilitated.

[0041] Embodiment 3

[0042] The main structure of this embodiment is the same as that of embodiment 1, and the difference lies in that the first bearing mechanism and the second bearing mechanism are further described in this embodiment.

[0043] Specifically, referring to Figure 2 , the first bearing mechanism comprises a support frame and two groups of mounting seats, the support frame is fixed on the moving platform 2, the two groups of mounting seats are parallel to each other and are respectively fixed at two ends of the support frame, and the two ends of the first workpiece to be assembled are fixedly connected with the two groups of mounting seats; the second bearing mechanism comprises two groups of mounting seats, the two groups of mounting seats are parallel to each other and are fixed on the fixed platform 3, and the two ends of the second workpiece to be assembled are fixedly connected with the two groups of mounting seats.

[0044] In this embodiment, the mounting seat structures of the first bearing mechanism and the second bearing mechanism are the same, the mounting seat is provided with a circular through hole, a ring plate is detachably fixedly installed in the circular through hole, the workpiece to be assembled is fixed in the center hole of the ring plate, and a buffer layer is arranged on the inner end face of the ring plate. This embodiment is suitable for high-precision automatic assembly of circular long columnar workpieces, different specifications of ring plates can be arranged to adapt to different specifications of workpieces to be assembled, and the application range of the equipment is improved.

[0045] In application, the workpiece to be assembled in the form of a circular long column is passed through the circular through hole of the mounting seat, and the ring plate with a size suitable for the diameter of the workpiece to be assembled is selected, the workpiece to be assembled is passed through the center hole of the ring plate, the ring plate is moved towards the mounting seat and the ring plate is fixedly installed with the mounting seat.

[0046] Embodiment 4

[0047] The main structure of this embodiment is the same as that of embodiment 2, and the difference lies in that the visual information acquisition mechanism is further described in this embodiment.

[0048] Specifically, referring to Figure 7The visual information acquisition mechanism comprises a long optical axis 8, two groups of X-axis connecting pieces 9, two groups of short optical axes 10, two groups of camera connecting pieces 11 and two groups of binocular vision camera modules 12. The long optical axis 8 is horizontally arranged and fixedly connected with the profile frame 1 through profile connecting pieces 13 at both ends. The X-axis connecting pieces 9 are slidingly installed on the long optical axis 8. The two groups of short optical axes 10 are fixedly connected with the two groups of X-axis connecting pieces 9 respectively. The two groups of camera connecting pieces 11 are fixedly connected with the two groups of short optical axes 10 respectively, and the camera connecting pieces 11 are distributed above the X-axis connecting pieces 9. The two groups of binocular vision camera modules 12 are fixedly installed on the two groups of camera connecting pieces 11 respectively. In addition, the visual information acquisition mechanism further comprises two groups of light supplement apertures 14, which are fixedly connected with the two groups of short optical axes 10 through aperture connecting pieces 15 respectively, and the light supplement apertures 14 are distributed below the binocular vision camera modules 12.

[0049] In the embodiment, the binocular vision camera module 12 can be measured and positioned through the target ball on the target, can detect the target image, obtain the target space coordinate and position through an algorithm, and control the mobile platform to move to align the flanges on both sides.

[0050] Embodiment 5

[0051] The main structure of the embodiment is the same as that of embodiment 3, and the difference lies in that the visual information acquisition mechanism is further described in the embodiment.

[0052] Specifically, referring to Figure 8 The visual information acquisition mechanism comprises a camera 16 (3D industrial camera), an L-shaped fixed plate 17, a driving motor 18, a cross rod 19, a tow chain 20 and a tow chain groove 21. The cross rod 19 and the tow chain groove 21 are fixed on the profile frame 1, and the L-shaped fixed plate 17 is slidingly connected with the cross rod 19. The output end of the driving motor 18 is drivingly connected with the L-shaped fixed plate 17, so as to drive the L-shaped fixed plate 17 to slide along the cross rod 19. One end of the tow chain groove 21 is fixed in the tow chain groove 21, and the other end is fixedly connected with the L-shaped fixed plate 17. The camera 16 is fixedly installed on the L-shaped fixed plate 17.

[0053] In the embodiment, the camera can be used to scan the target fixed on the first bearing mechanism to extract the feature points of the target and solve the corresponding space coordinate system. Then the camera can be used to scan the static part of the workpiece to be assembled to scan the space point cloud information of the static part of the workpiece to be assembled, fit the axis and solve the space equation of the axis. Then the camera can be used to scan the moving part of the workpiece to be assembled to capture the point cloud information of the moving part of the workpiece to be assembled. According to the captured point cloud information, the space shape of the moving part of the workpiece to be assembled is fitted, the space equation of the axis is calculated, the movement trajectory of the moving platform is calculated through matrix operation, the space pose of the moving part of the workpiece to be assembled is adjusted through the movement of the moving platform electric cylinder, and the axes of the two workpieces are overlapped. After the axes of the two workpieces are overlapped, the end faces of the two workpieces are overlapped through the moving platform to achieve the purpose of accurate assembly.

[0054] Embodiment 6

[0055] The main structure of the embodiment is the same as that of embodiment 4 or 5, and the difference lies in that the moving platform 2 is further described in the embodiment.

[0056] Specifically, referring to Figures 3-4 , the moving platform 2 includes a static plane 2-1, a dynamic plane 2-2 and six groups of leg structures which are the same in structure, and six legs are connected with the static plane 2-1 and the dynamic plane 2-2 in a "W" shape in two groups; the upper and lower ends of the leg structure are movably connected with the static plane 2-1 and the dynamic plane 2-2, respectively; the leg structure includes a servo motor 2-4 and an electric cylinder 2-5, the electric cylinder 2-5 is hinged with the dynamic plane 2-2 through an upper end hooke joint 2-6, and the electric cylinder 2-5 is hinged with the static plane 2-1 through a lower end hooke joint 2-3; the servo motor 2-4 is fixed on the electric cylinder 2-5 through a mounting piece to control the extension and contraction of the electric cylinder 2-5. The static plane 2-1 realizes the translational movement along X, Y and Z and the rotational movement around X, Y and Z through the extension and contraction of the electric cylinder 2-5, and the translational movement of the static plane 2-1 in space is completed through the extension and contraction movement of the six electric cylinders 2-5, so that various space movement postures can be simulated.

[0057] The preferred embodiments of the utility model are described above, the protection scope of the utility model is not limited to the above-mentioned embodiments only, any technical scheme belonging to the utility model idea is within the protection scope of the utility model, it should be pointed out that some improvements and decorations without departing from the principle of the utility model for the ordinary skilled in the art are regarded as the protection scope of the utility model.

Claims

1. A vision-guided parallel robot assembly system, characterized in that, it comprises a profile frame (1), a moving platform (2), a fixed platform (3) and a vision information acquisition mechanism; the moving platform (2) is a six-degree-of-freedom moving platform, a first bearing mechanism is fixedly installed on the moving platform (2), and a first workpiece to be assembled is detachably and fixedly installed on the first bearing mechanism; the fixed platform (3) is fixedly installed with a second bearing mechanism, and a second workpiece to be assembled is detachably and fixedly installed on the second bearing mechanism; the vision information acquisition mechanism is installed on the profile frame (1), and is distributed above the first workpiece to be assembled and the second workpiece to be assembled, and is used to acquire position information of the first workpiece to be assembled relative to the second workpiece to be assembled, and the moving platform (2) can move according to the position information so that the end faces of the first workpiece to be assembled and the second workpiece to be assembled coincide.

2. The vision-guided parallel robot assembly system according to claim 1, characterized in that, a moving end target (4) is arranged on the first bearing mechanism, and a fixed end target (5) is arranged on the second bearing mechanism; the moving end target (4) and the fixed end target (5) are the same structure, and each comprises a target base and a target ball, and the target ball is fixedly installed on the target base.

3. The vision-guided parallel robot assembly system according to claim 1, characterized in that, the first bearing mechanism comprises a support (6) and a first docking seat (7), the support (6) is fixed on the moving platform (2) and comprises two groups of parallel lower support rods, the ends of the two groups of lower support rods are connected by a connecting rod to form a door-shaped structure, at least one group of upper support rods is fixed on the door-shaped structure, and the first docking seat (7) is fixedly installed on the upper support rods; the second bearing mechanism comprises a second docking seat, the second docking seat is fixed on the fixed platform (3), and the second docking seat and the first docking seat (7) are respectively provided with a connecting flange for fixing the workpiece to be assembled.

4. The vision-guided parallel robot assembly system according to claim 1, characterized in that, the first bearing mechanism comprises a support frame and two groups of mounting seats, the support frame is fixed on the moving platform (2), the two groups of mounting seats are parallel to each other and are fixed on the two ends of the support frame, and the two ends of the first workpiece to be assembled are fixedly connected with the two groups of mounting seats respectively; the second bearing mechanism comprises two groups of mounting seats, the two groups of mounting seats are parallel to each other and are fixed on the fixed platform (3), and the two ends of the second workpiece to be assembled are fixedly connected with the two groups of mounting seats respectively.

5. The vision-guided parallel robot assembly system according to claim 4, characterized in that, the mounting seats of the first bearing mechanism and the second bearing mechanism are the same structure, the mounting seat is provided with a circular through hole, a ring plate is detachably and fixedly installed in the circular through hole, the workpiece to be assembled is fixed in the center hole of the ring plate, and a buffer layer is arranged on the inner end face of the ring plate.

6. The vision-guided parallel robot assembly system according to claim 1, characterized in that, The visual information acquisition mechanism comprises a long optical axis (8), two groups of X-axis connectors (9), two groups of short optical axes (10), two groups of camera connectors (11) and two groups of binocular vision camera modules (12); The long optical axis (8) is horizontally arranged and fixedly connected with the profile frame (1) through profile connectors (13) at both ends; the X-axis connectors (9) are slidingly installed on the long optical axis (8), the two groups of short optical axes (10) are fixedly connected with the two groups of X-axis connectors (9) respectively, the two groups of camera connectors (11) are fixedly connected with the two groups of short optical axes (10) respectively, and the camera connectors (11) are distributed above the X-axis connectors (9); and the two groups of binocular vision camera modules (12) are fixedly installed on the two groups of camera connectors (11) respectively.

7. The vision-guided parallel robot assembly system according to claim 6, wherein The visual information acquisition mechanism further comprises two groups of light supplement apertures (14), the two groups of light supplement apertures (14) are fixedly connected with the two groups of short optical axes (10) through aperture connectors (15) respectively, and the light supplement apertures (14) are distributed below the binocular vision camera modules (12).

8. The vision-guided parallel robot assembly system according to claim 1, wherein The visual information acquisition mechanism comprises a camera (16), an L-shaped fixed plate (17), a driving motor (18), a crossbar (19), a drag chain (20) and a drag chain slot (21); The crossbar (19) and the drag chain slot (21) are fixed on the profile frame (1), and the L-shaped fixed plate (17) is slidingly connected with the crossbar (19); the output end of the driving motor (18) is drivingly connected with the L-shaped fixed plate (17) to drive the L-shaped fixed plate (17) to slide along the crossbar (19); one end of the drag chain slot (21) is fixed in the drag chain slot (21), and the other end is fixedly connected with the L-shaped fixed plate (17); and the camera (16) is fixedly installed on the L-shaped fixed plate (17).

9. The vision-guided parallel robot assembly system according to claim 1, wherein The mobile platform (2) comprises a static plane (2-1), a dynamic plane (2-2) and six groups of leg structures which are the same in structure; The upper and lower ends of the leg structure are movably connected with the static plane (2-1) and the dynamic plane (2-2) respectively; The leg structure comprises a servo motor (2-4) and an electric cylinder (2-5), the electric cylinder (2-5) is hingedly connected with the dynamic plane (2-2) through an upper end hooke joint (2-6), and the electric cylinder (2-5) is hingedly connected with the static plane (2-1) through a lower end hooke joint (2-3); the servo motor (2-4) is fixed on the electric cylinder (2-5) through a mounting piece to control the extension and contraction of the electric cylinder (2-5).

10. The vision-guided parallel robot assembly system according to claim 1, wherein The mobile platform (2) is arranged inside the profile frame (1), and the fixed platform (3) is arranged outside the profile frame (1).

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