A gravity unloading attitude adjusting device and method suitable for heavy load assembly

Abstract

The application provides a gravity unloading attitude adjusting device and method suitable for heavy load assembly, four gravity unloading units are arranged on a carrying vehicle, a single gravity unloading unit comprises a plane air floating support mechanism, a support column, a vertical hydraulic cylinder and a spherical air floating support mechanism; a load platform is supported by the four gravity unloading units, the load platform is driven by an attitude adjusting driving unit to carry out six-degree-of-freedom position adjustment, so that the assembly body reaches a target assembly position. In the position adjustment process, the plane air floating support mechanism provides translational freedom and rotation freedom around the vertical direction, the four vertical hydraulic cylinders and the spherical air floating support mechanisms thereon jointly provide tilting freedom in any direction and vertical movement freedom, and support force is provided to offset the gravity of the load platform and its load, gravity unloading is realized, the driving load of the attitude adjusting driving unit is greatly reduced, the accuracy and feedback speed of the attitude adjusting process are provided, and oscillation is effectively avoided or reduced.

Description

Technical Field

[0001] This invention relates to the field of heavy-duty attitude adjustment and assembly technology, specifically to a gravity unloading attitude adjustment device and method suitable for heavy-duty assembly. Background Technology

[0002] Aerospace technology plays a crucial role in international technological competition. Faced with increasingly complex space missions such as close-range detection of extraterrestrial objects, space defense and attack, and diversified on-orbit services, spacecraft are trending towards larger size, heavier payloads, and greater complexity. To avoid collisions due to excessive inertia, significant amounts of time are required for manual marking, and the assembly process is extremely slow, severely impacting the assembly efficiency of large products. For example, the first-stage assembly of the Long March 5B core takes a month; replacing an engine on the C919 passenger jet requires 48 hours. The low assembly efficiency caused by the large weight and high rigidity of products is a bottleneck and pain point for the industry.

[0003] Most existing solutions focus on unloading the product's weight through compliant control of heavy-duty robotic arms. However, this method of unloading weight through robotic arms is difficult to withstand "ton-level" loads. For large products with heavy loads, the compliant control of robotic arms is limited by control accuracy and feedback speed, and the system is prone to oscillation. Therefore, the method of unloading and adjusting the posture of "ton-level" heavy loads through compliant control of robotic arms is unreliable.

[0004] In addition, there is a method of gravity unloading using a six-degree-of-freedom (DOF) attitude adjustment assembly table. Such devices typically achieve high-precision attitude adjustment through complex electromechanical structures, supporting large products for assembly and docking. However, the high requirements of compliant control algorithms for force feedback accuracy and system feedback speed conflict with the high inertia and high output load of large products, making the robustness of heavy-duty compliant control systems insufficient for application requirements. Therefore, conventional six-DOF attitude adjustment assembly tables employ rigid position control, resulting in slow motion cycles. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a gravity unloading and attitude adjustment device and method suitable for heavy-duty assembly.

[0006] This invention is achieved through the following technical solution: A gravity unloading and attitude adjustment device suitable for heavy-duty assembly includes: a transport vehicle and a gravity unloading unit, an attitude adjustment drive unit and a loading platform installed on the transport vehicle; The gravity unloading units are four in number and are arranged in a rectangular shape on the transport vehicle. The cargo platform is installed on these four gravity unloading units. Each gravity unloading unit includes a planar air-float support mechanism, a support column, a vertical hydraulic cylinder, and a spherical air-float support mechanism. The planar air-float support mechanism is installed on the transport vehicle, the support column is fixedly installed on the planar air-float movable platform of the planar air-float support mechanism, the vertical hydraulic cylinder is fixedly installed on the top of the support column, the spherical air-float support mechanism is located on the top of the actuating end of the vertical hydraulic cylinder, and the cargo platform is installed on the top of the spherical air-float support mechanism. The attitude adjustment drive unit is located below the loading platform and is used to drive the loading platform to perform six degrees of freedom attitude adjustment. During the attitude adjustment process, since the planar air-bearing support mechanism provides translational and rotational degrees of freedom around the vertical axis, the combined action of the four vertical hydraulic cylinders and the spherical air-bearing support mechanism above them provides the loading platform with tilting freedom in any direction and vertical movement freedom, while providing support force to counteract the gravity of the loading platform and its load, thereby achieving gravity unloading.

[0007] In the above technical solution, the transport vehicle is an AGV.

[0008] In the above technical solution, four mounting bases are set on the transport vehicle. These four mounting bases are arranged in a rectangular array and are used to install the gravity unloading unit.

[0009] In the above technical solution, the planar air-float support mechanism includes a planar air-float movable platform, a planar air-float base, a limiting baffle, and an elastic element. The planar air-float movable platform is set on the planar air-float base, the limiting baffle is fixedly set around the periphery of the planar air-float movable platform, and the elastic element is set between the limiting baffle and the planar air-float movable platform. Through the setting of the limiting baffle and the elastic element, a translational constraint force is provided for the planar air-float movable platform, ensuring the stability of the translational movement of the planar air-float movable platform and reducing its oscillation.

[0010] In the above technical solution, the spherical air-bearing support mechanism includes an air-bearing base, an air-bearing ball, and a movable support platform. The air-bearing base is installed on the top of the actuating end of the vertical hydraulic cylinder, the air-bearing ball is installed on the air-bearing base, and the movable support platform is fixedly connected to the air-bearing ball. The loading platform is supported by four movable support platforms. When the loading platform is subjected to external force (driven by the attitude adjustment drive unit), its tilt angle changes, and the extension and retraction lengths of the four vertical hydraulic cylinders change accordingly. At the same time, the tilt angles of the four movable support platforms are adaptively adjusted according to the loading platform.

[0011] In the above technical solution, the attitude adjustment drive unit adopts three serially connected seven-degree-of-freedom light-load robotic arms.

[0012] In the above technical solution, the loading platform is provided with tooling units for installing the assembly to be assembled.

[0013] In the above technical solution, the tooling unit includes a clamp and two arc-shaped bases. The clamp is located in the middle of the two arc-shaped bases, and the cylindrical assembly is installed between the clamp and the two arc-shaped bases.

[0014] In the above technical solution, rollers are arranged on the clamp and two arc-shaped bases. The rollers are driven by a motor, thereby realizing the adjustment of the axial rotation angle of the cylindrical assembly.

[0015] The specific implementation steps for transferring and assembling large products using this device are as follows: Step 1: With the four vertical hydraulic cylinders in the closed state, the assembly is installed on the loading platform from the ground using a lifting device; Step 2: Transfer the assembly to the designated assembly location using a transport vehicle, and then lock the current position of the transport vehicle; Step 3: Set the three tandem seven-DOF light-load robotic arms of the attitude adjustment drive unit to follow-up mode, and simultaneously control the four vertical hydraulic cylinders to lift the loading platform to the set height. Step 4: Switch the attitude adjustment drive unit to active drive mode and put the four vertical hydraulic cylinders into constant force support control mode. Drive the load platform to perform six-degree-of-freedom attitude adjustment through the attitude adjustment drive unit so that the assembly can reach the target assembly posture. Step 5: After assembly, disconnect the assembly from the platform, clear the end force of the attitude adjustment drive unit, and then activate the follow-up mode; then close the four vertical hydraulic cylinders, unlock the wheels of the transport vehicle, and transfer it to the initial position.

[0016] The advantages and beneficial effects of this invention are as follows: This invention incorporates four gravity unloading units on a transport vehicle. Each gravity unloading unit includes a planar air-bearing support mechanism, a support column, a vertical hydraulic cylinder, and a spherical air-bearing support mechanism. These four gravity unloading units support the loading platform. During operation, the assembly to be assembled is mounted on the loading platform. The platform is then driven by an attitude adjustment drive unit to perform six-degree-of-freedom attitude adjustment, bringing the assembly to the target assembly posture. During attitude adjustment, the planar air-bearing support mechanism provides translational and rotational degrees of freedom around the vertical axis. The combined action of the four vertical hydraulic cylinders and the spherical air-bearing support mechanism provides the loading platform with tilting freedom in any direction and vertical movement freedom, while simultaneously providing support force to counteract the gravity of the loading platform and its load, thus achieving gravity unloading. This significantly reduces the driving load on the attitude adjustment drive unit, thereby improving the accuracy and feedback speed of the attitude adjustment process, effectively avoiding or reducing oscillations, achieving high-precision compliant attitude adjustment for "ton-level" loads, reducing the difficulty of heavy-duty assembly operations, improving assembly efficiency and safety, and providing solutions for the precise and efficient manufacturing of large components in high-end equipment fields such as aerospace, marine vessels, and heavy machinery.

[0017] In addition, a tooling unit for mounting the assembly to be assembled is set on the loading platform. The tooling unit includes a clamp and two arc-shaped bases, on which rollers are arranged. The rollers can be driven by a motor, thereby adjusting the axial rotation angle of the cylindrical assembly. Then, in the assembly scenario of the cylindrical assembly, the position and attitude adjustment mechanism is used to adjust the loading platform and the axial rotation angle of the cylindrical assembly to align the bolt holes on the flange of the cylindrical assembly with the bolt holes on the flange of the target assembly. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a structural schematic diagram of the gravity unloading and attitude adjustment device of the present invention, which is suitable for heavy-duty assembly.

[0020] Figure 2 This is a schematic diagram of the structure of the transport vehicle in this invention.

[0021] Figure 3 This is a schematic diagram of the gravity unloading unit in this invention.

[0022] Figure 4 This is a schematic diagram of the attitude adjustment drive unit in this invention.

[0023] Figure 5 This is a schematic diagram of the cargo platform in this invention. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present invention, the technical solution of the present invention will be further described below with reference to specific embodiments.

[0025] This invention provides a gravity unloading and attitude adjustment device suitable for heavy-duty assembly, see attached document. Figure 1 The device includes: a transport vehicle 1, a gravity unloading unit 2, an attitude adjustment drive unit 3, and a cargo platform 4 mounted on the transport vehicle 1.

[0026] See appendix Figure 2 The transport vehicle 1 is preferably an AGV (Automated Guided Vehicle). Four mounting bases 11 are provided on the transport vehicle 1, and these four mounting bases 11 are arranged in a rectangular array.

[0027] Four gravity unloading units 2 are respectively installed on four mounting bases 11 on the transport vehicle 1; the cargo platform 4 is installed on these four gravity unloading units 2. These four gravity unloading units 2 are used to support the cargo platform 4, providing the cargo platform 4 with four vertical degrees of freedom of movement (degrees of freedom of movement along the Z-axis), while providing a constant force to counteract the gravity of the cargo platform 4 and its load, while providing the cargo platform 4 with tilting degrees of freedom (degrees of freedom of rotation about the X and Y axes), while providing the cargo platform 4 with translational degrees of freedom (degrees of freedom of movement along the X and Y axes), and while providing the cargo platform 4 with a vertical rotational degree of freedom (degrees of freedom of rotation about the Z-axis).

[0028] For details, please see the appendix. Figure 3 The gravity unloading unit 2 includes a planar air-floating support mechanism 21, a support column 22, a vertical hydraulic cylinder 23, and a spherical air-floating support mechanism 24.

[0029] The planar air-bearing support mechanism 21 is mounted on the mounting base 11 of the carrier vehicle 1, providing translational degrees of freedom (movement degrees of freedom along the X and Y axes) and rotational degrees of freedom about the vertical axis (rotational degrees of freedom about the Z axis). Further, as a preferred embodiment, the planar air-bearing support mechanism 21 includes a planar air-bearing movable platform 211, a planar air-bearing base 212, a limiting baffle 213, and an elastic element 214. The planar air-bearing movable platform 211 is disposed on the planar air-bearing base 212. Preferably, the planar air-bearing movable platform 211 is circular, and its bottom is provided with micro-holes that can eject compressed air to create a gap between it and the planar air-bearing base 212. An air film is used to achieve micro-friction or even zero-friction support for the planar air-floating movable platform 211. A limiting baffle 213 is fixedly installed around the planar air-floating movable platform 211, and an elastic element 214 is installed between the limiting baffle 213 and the planar air-floating movable platform 211 (one end of the elastic element 214 is connected to the inner wall of the limiting baffle 213, and the other end is connected to the outer wall of the planar air-floating movable platform 211). Preferably, there are four elastic elements 214, which are evenly distributed. Through the setting of the limiting baffle 213 and the elastic element 214, a certain translational constraint force is provided for the planar air-floating movable platform 211, ensuring the stability of the translational movement of the planar air-floating movable platform 211 and reducing its oscillation.

[0030] The support column 22 is fixedly installed on the planar air-floating movable platform 211 of the planar air-floating support mechanism 21, and moves synchronously with it in the plane. The support column 22 provides sufficient support height for the cargo platform 4.

[0031] The vertical hydraulic cylinder 23 is fixedly installed on the top of the support column 22, providing the vertical movement degree of freedom (movement degree of freedom along the Z-axis) for the loading platform 4, while providing a constant force to counteract the gravity of the loading platform 4 and its load.

[0032] The spherical air-float support mechanism 24 is located at the top of the actuating end of the vertical hydraulic cylinder 23. The loading platform 4 is mounted on top of the spherical air-float support mechanism 24. The spherical air-float support mechanism 24 provides the loading platform 4 with tilting freedom in any direction (rotational freedom about the X and Y axes). Under the action of air float, it can achieve micro-friction or even zero-friction support for the loading platform 4. For further details, see the appendix. Figure 3The spherical air-bearing support mechanism 24 includes an air-bearing seat 241, an air-bearing ball 242, and a movable support platform 243. The air-bearing seat 241 is installed on the top of the actuating end of the vertical hydraulic cylinder 23, the air-bearing ball 242 is installed on the air-bearing seat 241, and the movable support platform 243 is fixedly connected to the air-bearing ball 242. Under the action of air buoyancy, the air-bearing ball 242 can perform micro-friction or even zero-friction tilting motion in any direction on the air-bearing seat 241. The movable support platform 243 moves synchronously with the air-bearing ball 242. The loading platform 4 is supported by four movable support platforms 243 (that is, the loading platform 4 is supported by four movable support platforms 243 of the gravity unloading unit 2). When the loading platform 4 is subjected to external force (driven by the attitude adjustment drive unit 3), its tilt angle changes. The extension and retraction length of the four vertical hydraulic cylinders 23 changes accordingly to maintain a constant supporting force. At the same time, the tilt angle of the four movable support platforms 243 is adaptively adjusted with the loading platform 4.

[0033] The attitude adjustment drive unit 3 is located below the loading platform 4 and is used to drive the loading platform 4 to perform six degrees of freedom attitude adjustment (including: movement along the X, Y, and Z directions, and rotation around the X, Y, and Z directions). The assembly 5 to be assembled is installed on the loading platform 4. During attitude adjustment, the assembly 5 moves synchronously with the loading platform 4 to achieve attitude adjustment of the assembly 5. During the attitude adjustment process, the planar air-bearing support mechanism 21 provides translational degrees of freedom (movement freedom along the X and Y axes) and rotational degrees of freedom around the vertical axis (rotational degrees of freedom around the Z axis). The combined action of the four vertical hydraulic cylinders 23 and the spherical air-bearing support mechanism 24 on them provides the loading platform 4 with tilting degrees of freedom in any direction (rotational degrees of freedom around the X and Y axes) and vertical movement degrees of freedom (movement freedom along the Z axis). At the same time, it can provide a "ton-level" stable support force to counteract the gravity of the loading platform 4 and its load (the load refers to the assembly 5), thereby achieving gravity unloading. This greatly reduces the driving load of the attitude adjustment drive unit 3, thereby improving the accuracy and feedback speed of the attitude adjustment process and effectively avoiding or reducing oscillations.

[0034] For further details, please refer to the appendix. Figure 4 For example, the attitude adjustment drive unit 3 employs three tandem seven-DOF light-load robotic arms. These three robotic arms communicate with the control system and adjust the attitude of the loading platform 4 using light load force.

[0035] Alternatively, the posture adjustment drive unit 3 can also be a Stewart motion platform.

[0036] Furthermore, by incorporating position-based admittance control into the control system loop, the robotic arm gains flexibility, enabling it to avoid rigid collisions when encountering external disturbances. Specifically: Step 1: The admittance relationship for location-based admittance control can be expressed as:

[0037] The desired inertia matrix for admittance control. Let be the desired damping matrix. Let be the desired stiffness matrix. This represents the desired position of the robotic arm's end effector. This represents the actual position of the robotic arm's end effector. and These represent the actual contact force and the expected contact force between the robotic arm's end effector and the environment, respectively.

[0038] Step 2: Decouple the above equation into the admittance relationship of the robot arm force potential data in a single direction:

[0039] Here are the inertial parameters, damping parameters, and stiffness parameters in this degree of freedom direction. These are the actual and expected values ​​of the robotic arm's end effector in that degree of freedom direction, respectively. These are the actual and expected values ​​of the end effector force of the robotic arm in that degree of freedom direction, respectively. Based on the input expected position information... The motion angles of each joint of the robotic arm are calculated through inverse kinematics. After passing through the position loop, the deviation between the actual end force and the expected end force is calculated. The position offset in the direction of that degree of freedom is calculated through the admittance model to achieve a compliant effect and avoid interference such as scratches and collisions.

[0040] The specific implementation steps for transferring and assembling large products using this device are as follows: Step 1: With the four vertical hydraulic cylinders 23 in the closed state, the assembly 5 is installed onto the loading platform 4 from the ground using a lifting device. Preferably, the center of gravity of the assembly 5 is located on the central axis of the loading platform 4.

[0041] Step 2: Transfer assembly 5 to the designated assembly position using transport vehicle 1, and then lock the current position of transport vehicle 1 (i.e. lock the wheels of transport vehicle 1).

[0042] Step 3: Set the three tandem seven-DOF light-load robotic arms of the attitude adjustment drive unit 3 to follow-up mode, and simultaneously control the four vertical hydraulic cylinders 23 to lift the loading platform 4 to the set height.

[0043] Step 4: Switch the attitude adjustment drive unit 3 to active drive mode and put the four vertical hydraulic cylinders 23 into constant force support control mode. Drive the load platform 4 to perform six-degree-of-freedom attitude adjustment through the attitude adjustment drive unit 3 so that the assembly 5 can reach the target assembly posture.

[0044] During posture adjustment, in constant force support control mode, the piston rod positions of the four vertical hydraulic cylinders 23 are not fixed. They automatically adjust the extension and retraction length of the piston rods based on the force applied to the hydraulic cylinders (detected in real-time by force sensors on the cylinders). For example, when the pressure on the hydraulic cylinder exceeds the set constant force support threshold (i.e., during posture adjustment, the posture adjustment drive unit 3 drives the platform 4 to tilt, so the pressure on the hydraulic cylinder on the downward tilting side of the platform 4 exceeds the set constant force support threshold), the extension and retraction length of the hydraulic cylinder piston rod decreases; when the pressure on the hydraulic cylinder is less than the set constant force support threshold (i.e., during posture adjustment, the posture adjustment drive unit 3 drives the platform 4 to tilt, so the pressure on the hydraulic cylinder on the upward tilting side of the platform 4 is less than the set constant force support threshold), the extension and retraction length of the hydraulic cylinder piston rod increases.

[0045] Step 5: After assembly, disconnect assembly 5 from the loading platform 4, clear the end force of the attitude adjustment drive unit 3 and start the follow-up mode; then close the four vertical hydraulic cylinders 23, unlock the wheels of the transport vehicle 1 and transfer it to the initial position.

[0046] Furthermore, the loading platform 4 is equipped with tooling units for mounting the assemblies 5 to be assembled. See Appendix. Figure 1 For the cylindrical assembly 5, the tooling unit includes a clamp 41 and two arc-shaped bases 42. The clamp 41 is located in the middle of the two arc-shaped bases 42, and the cylindrical assembly 5 is installed between the clamp 41 and the two arc-shaped bases 42.

[0047] To elaborate further, see the appendix. Figure 5 Rollers 43 are arranged on the clamp 41 and the two arc-shaped bases 42. The rollers 43 can be driven by a motor to adjust the axial rotation angle of the cylindrical assembly 5.

[0048] See appendix Figure 1 An assembly scenario for a cylindrical assembly 5 is presented, wherein a flange is provided at the end of the assembly 5. During the attitude adjustment process, the attitude adjustment drive unit 3 adjusts the position and attitude of the loading platform 4 and the axial rotation angle of the cylindrical assembly 5 itself, so as to align the bolt holes on the flange of the cylindrical assembly 5 with the bolt holes on the flange of the target assembly 7 on the mounting bracket 6.

[0049] For ease of explanation, spatial relative terms such as “up,” “down,” “left,” and “right” are used in the embodiments to describe the relationship of one element or feature shown in the figures relative to another element or feature. It should be understood that, in addition to the orientations shown in the figures, spatial terms are intended to include different orientations of the device in use or operation. For example, if the device in the figures is inverted, an element described as being “down” of other elements or features would be positioned “up” of those other elements or features. Therefore, the exemplary term “down” can encompass both up and down orientations. The device may be positioned in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0050] Moreover, relational terms such as “first” and “second” are used merely to distinguish one component from another that has the same name, without necessarily requiring or implying any such actual relationship or order between the components.

[0051] The above description is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A gravity unloading and attitude adjustment device suitable for heavy-duty assembly, characterized in that: It includes a transport vehicle and a gravity unloading unit, an attitude adjustment drive unit, and a cargo platform mounted on the transport vehicle; The gravity unloading units are four in number and are arranged in a rectangular shape on the transport vehicle. The cargo platform is installed on these four gravity unloading units. Each gravity unloading unit includes a planar air-float support mechanism, a support column, a vertical hydraulic cylinder, and a spherical air-float support mechanism. The planar air-float support mechanism is installed on the transport vehicle, the support column is fixedly installed on the planar air-float movable platform of the planar air-float support mechanism, the vertical hydraulic cylinder is fixedly installed on the top of the support column, the spherical air-float support mechanism is located on the top of the actuating end of the vertical hydraulic cylinder, and the cargo platform is installed on the top of the spherical air-float support mechanism. The attitude adjustment drive unit is located below the loading platform and is used to drive the loading platform to perform six degrees of freedom attitude adjustment. During the attitude adjustment process, since the planar air-bearing support mechanism provides translational and rotational degrees of freedom around the vertical axis, the combined action of the four vertical hydraulic cylinders and the spherical air-bearing support mechanism above them provides the loading platform with tilting degrees of freedom in any direction and vertical movement degrees of freedom, while providing support force to counteract the gravity of the loading platform and its load.

2. The gravity unloading and attitude adjustment device suitable for heavy-duty assembly according to claim 1, characterized in that: The transport vehicle is an AGV (Automated Guided Vehicle).

3. The gravity unloading and attitude adjustment device suitable for heavy-duty assembly according to claim 1, characterized in that: Four mounting bases are set on the transport vehicle, and these four mounting bases are arranged in a rectangular array for mounting the gravity unloading unit.

4. The gravity unloading and attitude adjustment device suitable for heavy-duty assembly according to claim 1, characterized in that: The planar air-float support mechanism includes a planar air-float movable platform, a planar air-float base, a limiting baffle, and an elastic element. The planar air-float movable platform is mounted on the planar air-float base, the limiting baffle is fixedly mounted around the planar air-float movable platform, and the elastic element is positioned between the limiting baffle and the planar air-float movable platform. The limiting baffle and the elastic element provide translational constraint force to the planar air-float movable platform, ensuring the stability of its translational movement and reducing its oscillation.

5. The gravity unloading and attitude adjustment device suitable for heavy-duty assembly according to claim 1, characterized in that: The spherical air-bearing support mechanism includes an air-bearing base, an air-bearing ball, and a movable support platform. The air-bearing base is installed on the top of the actuating end of the vertical hydraulic cylinder, the air-bearing ball is installed on the air-bearing base, and the movable support platform is fixedly connected to the air-bearing ball. The loading platform is supported by four movable support platforms. When the loading platform is subjected to external force and its tilt angle changes, the extension and retraction lengths of the four vertical hydraulic cylinders change accordingly. At the same time, the tilt angles of the four movable support platforms are adaptively adjusted according to the loading platform.

6. The gravity unloading and attitude adjustment device suitable for heavy-duty assembly according to claim 1, characterized in that: The attitude adjustment drive unit uses three tandem seven-degree-of-freedom light-load robotic arms.

7. The gravity unloading and attitude adjustment device suitable for heavy-duty assembly according to claim 1, characterized in that: The platform is equipped with tooling units for installing the assemblies to be assembled.

8. The gravity unloading and attitude adjustment device suitable for heavy-duty assembly according to claim 7, characterized in that: The tooling unit includes a clamp and two arc-shaped bases. The clamp is located in the middle of the two arc-shaped bases, and the cylindrical assembly is installed between the clamp and the two arc-shaped bases.

9. The gravity unloading and attitude adjustment device suitable for heavy-duty assembly according to claim 8, characterized in that: Rollers are arranged on the clamp and two arc-shaped bases. The rollers are driven by a motor and are used to adjust the axial rotation angle of the cylindrical assembly.

10. The method for transferring and assembling a gravity unloading attitude adjustment device suitable for heavy-duty assembly according to claim 1, characterized in that, Includes the following steps: Step 1: With the four vertical hydraulic cylinders in the closed state, the assembly is installed on the loading platform from the ground using a lifting device; Step 2: Transfer the assembly to the designated assembly location using a transport vehicle, and then lock the current position of the transport vehicle; Step 3: Set the three tandem seven-DOF light-load robotic arms of the attitude adjustment drive unit to follow-up mode, and simultaneously control the four vertical hydraulic cylinders to lift the loading platform to the set height. Step 4: Switch the attitude adjustment drive unit to active drive mode and put the four vertical hydraulic cylinders into constant force support control mode. Drive the load platform to perform six-degree-of-freedom attitude adjustment through the attitude adjustment drive unit so that the assembly can reach the target assembly posture. Step 5: After assembly, disconnect the assembly from the platform, clear the end force of the attitude adjustment drive unit, and then activate the follow-up mode; then close the four vertical hydraulic cylinders, unlock the wheels of the transport vehicle, and transfer it to the initial position.

Images