Five-degree-of-freedom positioning device for heavy long component

Abstract

The invention belongs to the related technical field of positioning devices, and discloses a five-degree-of-freedom positioning device for a heavy long component, the positioning device comprises a lower-layer supporting platform, an upper-layer load platform, a center positioning assembly and a posture adjusting electric cylinder assembly, and the lower-layer supporting platform and the upper-layer load platform are arranged at an interval; the center positioning assembly and the posture adjusting electric cylinder assembly are both located between the lower layer supporting platform and the upper layer load platform. One end of the center positioning assembly is fixedly connected with the upper-layer load platform, and the other end of the center positioning assembly is hinged to the lower-layer supporting platform. One ends of the two posture adjusting electric cylinder assemblies are hinged to the two opposite ends of the upper-layer load platform respectively, and the other ends of the two posture adjusting electric cylinder assemblies are hinged to the two opposite ends of the lower-layer supporting platform respectively. According to the invention, five-degree-of-freedom accurate positioning and adjustment of the posture of the heavy long component can be realized.

Description

Technical Field

[0001] The present invention belongs to the technical field related to positioning devices, and more specifically, relates to a five-degree-of-freedom positioning device for heavy long components. Background Art

[0002] In the positioning and adjustment of heavy long components, due to the characteristics of the long components themselves, in addition to the translational adjustment along the length direction, multiple degrees of freedom adjustment capabilities are often required. At the same time, in order to facilitate subsequent operations after the component is positioned, the height of the adjustment platform is required to be within a certain range and it is required to have sufficient rigidity to resist the deformation of the component.

[0003] At present, the multi-degree-of-freedom positioning devices widely used in the prior art are mostly serial-parallel hybrid structures with four to six degrees of freedom adjustment capabilities, but this platform has many components and a high height, and due to the series connection between the degree-of-freedom adjustment components, the rigidity of the device is poor; another solution is a six-degree-of-freedom parallel adjustment platform. For long components, there is one more degree of adjustment freedom, and the mechanism is completely parallel, which requires decoupling of the movement, making it difficult to control. For example, patent CN108332941 discloses a serial-parallel hybrid multi-degree-of-freedom test device, which can achieve a maximum of six degrees of freedom for the component by superimposing adjustment modules with different degrees of freedom, but the overall height of the device is high, the rigidity is poor, and the control process is extremely complicated; patent CN205451654 discloses a six-degree-of-freedom adjustment platform, which can achieve six-degree-of-freedom movement, but its aspect ratio is relatively small, it is not suitable for the adjustment of heavy long components, and the end precision is difficult to control. Summary of the invention

[0004] In view of the above defects or improvement needs of the prior art, the present invention provides a five-degree-of-freedom positioning device for heavy long components, which aims to solve the problem of low positioning accuracy of the existing positioning devices.

[0005] To achieve the above-mentioned purpose, according to one aspect of the present invention, a five-degree-of-freedom positioning device for heavy-duty long components is provided, wherein the positioning device comprises a lower support platform, an upper load platform, a center positioning assembly and a posture adjustment electric cylinder assembly, wherein the lower support platform and the upper load platform are spaced apart; the center positioning assembly and the posture adjustment electric cylinder assembly are both located between the lower support platform and the upper load platform; one end of the center positioning assembly is fixedly connected to the upper load platform, and the other end is hinged to the lower support platform. One end of two posture adjustment electric cylinder assemblies are respectively hinged to the opposite ends of the upper load platform, and the other ends are respectively hinged to the opposite ends of the lower support platform;

[0006] The center positioning assembly is used to drive the upper load platform to move up and down in the vertical plane and to translate in the horizontal plane, and the posture adjustment electric cylinder assembly is used to drive the upper load platform to rotate in the vertical plane and to rotate in the horizontal plane.

[0007] Furthermore, the center positioning assembly includes a fixed plate, a ball joint, a connecting plate and two center positioning electric cylinders, one end of the two center positioning electric cylinders are spaced apart and are both hinged to the lower support platform, and the other end is hinged to the connecting plate; the two ends of the ball joint are respectively connected to the surface of the connecting plate away from the lower support platform and the fixed plate, and the fixed plate is connected to the upper load platform.

[0008] Furthermore, the geometric center of the ball joint and the geometric center of the upper load platform are located on the same straight line.

[0009] Furthermore, the posture adjustment electric cylinder assembly includes two electric cylinders arranged at intervals, and two ends of the electric cylinders are respectively hinged to the upper load platform and the lower support platform.

[0010] Furthermore, the two posture adjustment electric cylinder assemblies are respectively located at two ends of the lower support platform and the upper load platform.

[0011] Furthermore, the center positioning assembly is located in the middle of the storage space formed by the lower support platform and the upper load platform.

[0012] Furthermore, the posture adjustment electric cylinder assembly and the center positioning electric cylinder are both powered by servo motors and are controlled by servo motor drivers.

[0013] Furthermore, the servo motors connected to the posture adjustment electric cylinder assembly and the center positioning electric cylinder are both equipped with rotary encoders.

[0014] In general, compared with the prior art, the five-degree-of-freedom positioning device for heavy long members provided by the present invention has the following beneficial effects:

[0015] 1. The present invention can realize the up and down movement of the center of the load platform in the vertical plane and the translational movement in the horizontal plane through the telescopic movement of the two center positioning electric cylinders, and can realize the rotational movement of the upper load platform in the vertical plane and the rotational movement in the horizontal plane through the telescopic movement of the posture adjustment electric cylinder assembly. The translational freedom of the center positioning assembly in the length direction of the component is limited by the hinges at both ends of the center positioning electric cylinder. At the same time, a ball joint of the center positioning assembly is provided. While providing support, the ball joint limits the geometric center of the upper load platform according to the positioning position of the center positioning electric cylinder group, which can meet the support requirements of the component center and the requirements of translational motion control accuracy, thereby realizing five-degree-of-freedom positioning and adjustment of the long component.

[0016] 2. The center positioning electric cylinder assembly and the posture adjustment electric cylinder assembly of the present invention both use servo motor driver control to achieve active control. By giving different control signals to the servo motor driver through the controller, they can conveniently perform translational and rotational movements respectively, thereby improving the positioning control accuracy.

[0017] 3. The present invention realizes direct positioning of the geometric center of the upper load platform relative to the geometric center of the lower support platform through the center positioning component, and separates the up and down movement in the vertical plane and the translational movement in the horizontal plane from other rotational movements in control. By adjusting the translational degree of freedom first and then the rotational degree of freedom, its motion analysis and positioning control are simpler than those of the conventional parallel structure, and the positioning control accuracy is improved.

[0018] 4. The positioning device is a series-parallel hybrid structure. On the one hand, by separately controlling the translational degrees of freedom and rotational degrees of freedom of the upper load platform, the singular configuration problem that may be caused by a general multi-degree-of-freedom parallel mechanism is avoided; on the other hand, the series connection of the two parallel mechanisms does not introduce a new moving platform like a general series structure, but still realizes the series connection of the two parallel mechanisms between the original two platforms, so that the rigidity of the positioning device is greater than that of the general series and series-parallel hybrid mechanisms, and the positioning accuracy of the end of the positioning device is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a five-degree-of-freedom positioning device for a heavy long member provided by the present invention;

[0020] Figure 2 yes Figure 1 Schematic diagram of the structure of the center positioning assembly of the five-degree-of-freedom positioning device for heavy and long components.

[0021] In all the drawings, the same reference numerals are used to represent the same elements or structures, wherein: 10 - lower support platform, 20 - upper load platform, 30 - center positioning assembly, 40 - posture adjustment electric cylinder assembly, 31 - center positioning electric cylinder, 32 - connecting plate, 33 - ball joint, 34 - fixing plate. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0023] The present invention provides a five-degree-of-freedom positioning device for heavy-duty long members, the positioning device is a series-parallel hybrid mechanism, wherein the lower support platform and the upper load platform form a two-degree-of-freedom parallel mechanism for horizontally and vertically positioning the center position of the upper load platform through a center positioning component, and after completing the center positioning of the upper load platform, the lower support platform and the upper load platform form a three-degree-of-freedom parallel mechanism through a posture adjustment electric cylinder component to adjust the posture of the upper load platform. The positioning device is a series-parallel hybrid mechanism formed by connecting these two parallel mechanisms in series. This series-parallel hybrid mechanism avoids the singular configurations that may be generated by general six-degree-of-freedom parallel mechanisms in structural design, and avoids the danger of losing control of the adjustment of the applicable heavy-duty long members due to encountering singular configurations.

[0024] Among them, the fixed and moving platforms of the two parallel mechanisms are the same. The series connection of the two parallel mechanisms is different from the general stacking form. No moving platform is added. When there is only one moving platform, the upper load platform, the stiffness of the positioning device is greater than that of the general series and series-parallel mixed mechanisms. The posture adjustment electric cylinder directly adjusts the posture of the two ends of the upper load platform. The elongation of the electric cylinder is read by the rotary encoder and closed-loop control is performed to ensure the positioning accuracy of the positioning device.

[0025] See also Figure 1 and Figure 2, the positioning device includes a lower support platform, an upper load platform, a center positioning assembly and a posture adjustment electric cylinder assembly, and the lower support platform and the upper load platform are spaced apart. The center positioning assembly and the posture adjustment electric cylinder assembly are both located between the lower support platform and the upper load platform. One end of the center positioning assembly is fixedly connected to the upper load platform, and the other end is hinged to the lower support platform. One end of the two posture adjustment electric cylinder assemblies are respectively hinged to the opposite ends of the upper load platform, and the other ends are respectively hinged to the opposite ends of the lower support platform. The center positioning assembly is used to drive the upper load platform to move up and down in the vertical plane and to translate in the horizontal plane, and the posture adjustment electric cylinder assembly is used to drive the upper load platform to rotate in the vertical plane and to rotate in the horizontal plane.

[0026] The center positioning assembly includes a fixed plate, a ball joint, a connecting plate and two center positioning electric cylinders, one end of the two center positioning electric cylinders is spaced apart and both are hinged to the lower support platform, and the other end is hinged to the connecting plate. The two ends of the ball joint are respectively connected to the surface of the connecting plate away from the lower support platform and the fixed plate, and the fixed plate is connected to the upper load platform. In this embodiment, the geometric center of the ball joint and the geometric center of the upper load platform are located on the same straight line.

[0027] The two ends of the two center positioning electric cylinders are respectively hinged to limit the translational freedom of the center positioning assembly in the length direction of the component. At the same time, the ball joint limits the geometric center of the upper load platform according to the positioning position of the center positioning electric cylinder while providing support. This can meet the support requirements of the component center and the requirements of translational motion control accuracy, thereby realizing five-degree-of-freedom positioning adjustment of long components.

[0028] The posture adjustment electric cylinder assembly includes two electric cylinders arranged at intervals, the two ends of the electric cylinders are respectively hinged to the upper load platform and the lower support platform, and the two posture adjustment electric cylinder assemblies are respectively located at the two ends of the lower support platform and the upper load platform.

[0029] The center positioning assembly is located in the middle of the storage space formed by the lower support platform and the upper load platform.

[0030] The posture adjustment electric cylinder assembly and the center positioning electric cylinder are both powered by servo motors and controlled by servo motor drivers. The posture adjustment electric cylinder assembly and the center positioning electric cylinder both use the brake of the servo motor to control the locking and releasing of the electric cylinder.

[0031] In one embodiment, the servo motors connected to the posture adjustment electric cylinder assembly and the center positioning electric cylinder are both equipped with rotary encoders.

[0032] The center positioning electric cylinder is controlled by a servo motor driver, and the position of the connecting plate is controlled by the telescopic movement of the two electric cylinders. The upper load platform can move up and down in the vertical plane and translate in the horizontal plane by relying on the fixed connection between the ball joint, the fixed plate and the upper load platform. When the two electric cylinders extend or retract in the same direction, the upper load platform can move up and down in the vertical plane. When the two electric cylinders extend or retract in opposite directions, the upper load platform can translate in the horizontal plane. When the upper load platform's up and down movement in the vertical plane and its translate in the horizontal plane are controlled by the center positioning assembly, the electric cylinder in the posture adjustment electric cylinder assembly moves according to the corresponding control to provide support for the upper load platform.

[0033] The ball joint is preferably a gap-free ball joint to ensure the positioning accuracy of the upper load platform.

[0034] The posture adjustment electric cylinder assembly is controlled by a servo motor driver. When the upper load platform moves up and down in the vertical plane and translates in the horizontal plane under the control of the center positioning electric cylinder, the electric cylinder in the posture adjustment electric cylinder assembly moves according to the corresponding control to provide support for the upper load platform.

[0035] After completing the up and down movement of the upper load platform in the vertical plane and the translational movement in the horizontal plane, the two electric cylinders in each of the posture adjusting electric cylinder assemblies move in the same direction, the electric cylinders of the two posture adjusting electric cylinder assemblies move in the same direction, and when the motion states of the electric cylinders of the two posture adjusting electric cylinder assemblies are symmetrical about the center plane of the upper load platform, the upper load platform rotates in another direction around the geometric center of the ball joint in the vertical plane, and when the electric cylinders of each of the posture adjusting electric cylinder assemblies move in the opposite direction, and when the motion states of the electric cylinders of the two posture adjusting electric cylinder assemblies are symmetrical about the geometric center of the upper load platform, the upper load platform rotates around the geometric center of the ball joint in the horizontal plane.

[0036] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A five-degree-of-freedom positioning device for heavy and long components, characterized in that: The positioning device comprises a lower support platform, an upper load platform, a center positioning assembly and a posture adjustment electric cylinder assembly, wherein the lower support platform and the upper load platform are spaced apart; the center positioning assembly and the posture adjustment electric cylinder assembly are both located between the lower support platform and the upper load platform; one end of the center positioning assembly is fixedly connected to the upper load platform, and the other end is hinged to the lower support platform; one end of two posture adjustment electric cylinder assemblies are respectively hinged to the two opposite ends of the upper load platform, and the other ends are respectively hinged to the two opposite ends of the lower support platform; The center positioning assembly is used to drive the upper load platform to move up and down in the vertical plane and to translate in the horizontal plane, and the posture adjustment electric cylinder assembly is used to drive the upper load platform to rotate in the vertical plane and to rotate in the horizontal plane.

2. The five-degree-of-freedom positioning device for heavy and long components according to claim 1, characterized in that: The center positioning assembly includes a fixed plate, a ball joint, a connecting plate and two center positioning electric cylinders. One end of the two center positioning electric cylinders are spaced apart and are both hinged to the lower support platform, and the other end is hinged to the connecting plate; the two ends of the ball joint are respectively connected to the surface of the connecting plate away from the lower support platform and the fixed plate, and the fixed plate is connected to the upper load platform.

3. The five-degree-of-freedom positioning device for heavy and long components according to claim 2, characterized in that: The geometric center of the ball joint and the geometric center of the upper load platform are located on the same straight line.

4. The five-degree-of-freedom positioning device for heavy long components according to claim 1, characterized in that: The posture adjustment electric cylinder assembly includes two electric cylinders arranged at intervals, and two ends of the electric cylinders are respectively hinged to the upper load platform and the lower support platform.

5. The five-degree-of-freedom positioning device for heavy long members according to claim 4, characterized in that: The two posture adjustment electric cylinder assemblies are respectively located at two ends of the lower support platform and the upper load platform.

6. The five-degree-of-freedom positioning device for heavy long members according to claim 5, characterized in that: The center positioning assembly is located in the middle of the storage space formed by the lower support platform and the upper load platform.

7. The five-degree-of-freedom positioning device for heavy long members according to claim 2, characterized in that: The posture adjustment electric cylinder assembly and the center positioning electric cylinder are both powered by servo motors and are controlled by servo motor drivers.

8. The five-degree-of-freedom positioning device for a heavy long member according to claim 7, characterized in that: The servo motors connected to the posture adjustment electric cylinder assembly and the center positioning electric cylinder are both equipped with rotary encoders.

Images