Parallel type six-degree-of-freedom moving in-place milling and grinding robot

Abstract

The invention relates to a parallel type six-degree-of-freedom moving in-place milling and grinding robot which comprises a working platform and a moving platform which are connected through three identical moving branch chains and have two operation modes of a milling and grinding working state and an in-place moving state. In a milling and grinding working state, the movable platform is a static platform, and the working platform is a movable platform; in the in-place moving state, the moving platform is a movable platform, and the working platform is a static platform. The robot is simple in structure, and the six-degree-of-freedom effect of the end effector can be achieved through the three movement branch chains. And the method has relatively high flexibility and relatively high precision, and can meet operation requirements in a complex environment. Compared with a traditional six-degree-of-freedom parallel robot such as a Stewart platform, the six-degree-of-freedom parallel robot has better kinematics analysis capability and better stability, and is suitable for various application scenes with high precision and dynamic performance requirements.

Description

Technical Field

[0001] The invention relates to the technical field of robot operation, in particular to a parallel six-degree-of-freedom mobile in-situ milling robot. Background Art

[0002] In modern manufacturing, the processing requirements for large structural parts are getting higher and higher, especially in the fields of aerospace, automobile manufacturing, shipbuilding, etc. These structural parts are usually large in size, complex in shape, and have strict requirements on processing accuracy and efficiency. Therefore, how to choose a suitable robot system for efficient processing has become an urgent problem to be solved in the industry.

[0003] As two common industrial robots, parallel robots and serial robots each have their own advantages and disadvantages in the processing of large structural parts. Although parallel robots have advantages in precision and speed, they are often difficult to handle in the processing of oversized or heavy structural parts due to their limited workspace, complex structure and low flexibility. Although serial robots have a larger workspace and stronger flexibility, they lack rigidity and have a greater impact of error accumulation. They are easily affected by vibration and deformation during high-precision processing. Especially when processing large-sized structural parts, the carrying capacity of serial robots will also be challenged. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a parallel six-degree-of-freedom mobile in-situ milling robot, which not only simplifies the complex structure of the traditional six-degree-of-freedom robot and reduces the manufacturing cost, but also has strong flexibility and high precision, and can meet the operation requirements in complex environments. Compared with traditional six-degree-of-freedom parallel robots such as Stewart platforms, the present invention has better kinematic analysis capabilities and better stability, and is suitable for a variety of application scenarios with high precision and dynamic performance requirements.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical scheme: a parallel six-degree-of-freedom mobile in-situ milling and grinding robot, including a working platform, a mobile platform, a milling and grinding head, and three PUPU motion branches connecting the working platform and the mobile platform, including a milling and grinding working state and an in-situ moving state; in the milling and grinding working state, the mobile platform is a static platform and the working platform is a dynamic platform; in the in-situ moving state, the mobile platform is a dynamic platform and the working platform is a static platform.

[0006] In a preferred embodiment: in the milling working state, the mobile platform is adsorbed on the surface of the part to be processed by the branch chain and remains stationary, and the working platform drives the milling head to work; in the in-place moving state, the working platform is adsorbed on the surface of the part to be processed and remains stationary, and the mobile platform drives the branch chain to adjust the position of the robot, thereby realizing the switching between the robot milling working state and the in-place moving state.

[0007] In a preferred embodiment: in the milling working state, the working platform and the milling head have the ability to move in space with 6 degrees of freedom, and can complete the milling operations of complex surfaces of large structural parts in situ; in the on-site moving state, the mobile platform has the ability to move in space with 6 degrees of freedom, and the relative position of the parallel six-degree-of-freedom mobile on-site milling robot on the large structural parts can be changed by adjusting the three PUPU motion branches.

[0008] In a preferred embodiment: three PUPU motion branches are successively distributed with a first moving pair, a first Hooke's joint, a second moving pair and a second Hooke's joint from the moving platform to the working platform.

[0009] In a preferred embodiment: the axis of the first movable pair is perpendicular to the first axis of the first Hooke's joint; the second axis of the first Hooke's joint is perpendicular to the axis of the second movable pair; the axis of the second movable pair is perpendicular to the first axis of the second Hooke's joint; the second axis of the first Hooke's joint is perpendicular to the second axis of the second Hooke's joint.

[0010] In a preferred embodiment: when the robot is in working state, the mobile platform is a static platform, and the mobile platform contacts the surface of the part to be processed through three support arms evenly distributed around the circumference. The lower end of the support arm is installed with a first adsorption device. When in the milling working state, the first adsorption device is adsorbed on the surface of the part to be processed, so that the support arm is fastened to the surface of the part to be processed.

[0011] In a preferred embodiment: in the milling working state, the working platform is a moving platform with six degrees of freedom, and the milling head is installed in the middle position of the working platform.

[0012] In a preferred embodiment: the working platform is equipped with three telescopic devices with the same structure and symmetrical arrangement, and a second adsorption device is installed at the bottom of the telescopic device.

[0013] In a preferred embodiment: when the robot switches from the milling working state to the on-site moving state, the telescopic device on the working platform extends downward, and after the bottom of the telescopic device contacts the surface of the part to be processed, the telescopic device is adsorbed on the surface of the part to be processed through the second adsorption device, and then the first adsorption devices on the three PUPU motion branches stop adsorbing on the surface of the part to be processed, and the telescopic device continues to extend, so that the three PUPU motion branches leave the working part to be processed, and after adjusting the moving platform to reach the specified position, the telescopic device is lowered, and the first adsorption devices on the three PUPU motion branches are adsorbed on the surface of the part to be processed again, and the second adsorption device of the telescopic device stops adsorbing on the working surface of the part to be processed, and the telescopic device leaves the surface of the part to be processed, and the robot moves to the specified processing position by repeating the above steps.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1) The novel parallel six-degree-of-freedom mobile in-situ milling robot of the present invention only needs three motion branches to realize the six-degree-of-freedom motion of the terminal mechanism, which effectively simplifies the complex structure of the current six-degree-of-freedom robot and greatly reduces the manufacturing difficulty and manufacturing cost of the six-degree-of-freedom parallel robot.

[0015] 2) The novel parallel six-degree-of-freedom mobile in-situ milling robot of the present invention can switch the in-situ mobile state. The robot can walk on the surface to be processed of large structural parts, thereby overcoming the problem of small working space of the parallel robot and effectively expanding the working space of the parallel robot.

[0016] 3) The structure of each branch chain of the novel parallel six-degree-of-freedom mobile in-situ milling and grinding robot of the present invention is relatively simple. Due to its special configuration, the traditional six-degree-of-freedom parallel structure Stewart platform has not yet solved the analytical solution of its kinematic solution, and the singular position is very complex; the novel parallel six-degree-of-freedom mobile in-situ milling and grinding robot proposed in the present invention can accurately solve the analytical solution of its motion kinematic solution, and the motion stability of the mechanism can achieve the expected motion effect.

[0017] 4) The novel parallel six-degree-of-freedom mobile in-situ milling and grinding robot of the present invention not only has the advantages of high rigidity, high precision and high dynamic performance of the parallel robot, but also has the advantage of high flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of a preferred embodiment of the present invention; Figure 2 A schematic diagram of a kinematic branch chain according to a preferred embodiment of the present invention; Figure 3 A schematic diagram of a hydraulic cylinder telescope according to a preferred embodiment of the present invention; Figure 4 A schematic diagram of an electric retractor according to a preferred embodiment of the present invention; In the figure, 1-mobile platform, 2-support arm, 3-support foot, 4-milling head, 5-working platform, 6-electric telescopic rod, 7-mobile slider, 8-stepping motor, 9-support arm electromagnet, 10-hydraulic cylinder telescope, 11-support foot electromagnet, 12-screw, 13-push rod motor, 14-hydraulic upper push rod, 15-hydraulic lower push rod, 16-electric upper push rod, 17-electric lower push rod, P1-first mobile pair, P2-second mobile pair, U1-first Hooke's hinge, U2-second Hooke's hinge, L1-first motion branch chain, L2-second motion branch chain, L3-third motion branch chain. DETAILED DESCRIPTION

[0019] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0020] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0021] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

[0022] like Figure 1-4 As shown, the novel parallel six-degree-of-freedom mobile in-situ milling robot comprises a mobile platform 1 and a working platform 5, wherein the mobile platform 1 and the working platform 5 are connected via a first motion branch chain L1, a second motion branch chain L2 and a third motion branch chain L3.

[0023] The first motion branch chain L1, the second motion branch chain L2 and the third motion branch chain L3 are evenly distributed around the circumference, and the circumferential distribution of the three motion branches makes the forces balanced in the working state, ensuring the stability of the new parallel six-degree-of-freedom mobile in-situ milling robot during operation. The three motion branches are also respectively connected to the electric telescopic rod 6, and the structures of the three motion branches are exactly the same, that is, each motion branch between the working platform and the mobile platform is connected in sequence by the first mobile pair P1, the first Hooke's joint U1, the second mobile pair P2, and the second Hooke's joint U2.

[0024] Specifically, the new parallel six-degree-of-freedom mobile in-situ milling and grinding robot has six drive inputs, namely three first moving pairs P1 and three second moving pairs P2. The first moving pair P1 is composed of a lead screw 12 and a moving slider 7, wherein the lead screw 12 is driven by a stepper motor 8; the second moving pair P2 is composed of an electric upper push rod 16 and an electric lower push rod 17, which are driven by a push rod motor 13.

[0025] Specifically, when the parallel robot is in the milling working state, the mobile platform 1 is a static platform and the working platform 5 is a dynamic platform. The mobile platform 1 contacts the working surface through three support arms 2 evenly distributed around the circumference. The support arm electromagnet 9 is installed at the lower end of the support arm 2. When the support arm electromagnet 9 is energized during operation, the support arm electromagnet 9 generates a magnetic field, which generates an attractive force with the iron working plane, so that the support arm 2 is fastened to the working surface to ensure the stability of the processing; in the milling working state, the working platform 5 is a dynamic platform with six degrees of freedom, and the milling head 4 is installed in the middle position of the working platform. The milling head 4 can perform stable operations in this state.

[0026] Specifically, when the parallel robot is in the in-place moving state, the mobile platform 1 is a moving platform, and the working platform 5 is a static platform. Three hydraulic cylinder telescopes 10 are installed on the working platform 5, and the three hydraulic cylinder telescopes 10 are evenly distributed along the circumference. The lower ends of the hydraulic cylinder telescopes 10 are connected to the support feet 3 through the hydraulic upper push rod 14 and the hydraulic lower push rod 15, and the support foot electromagnet 11 is installed inside the support foot 3. When the parallel robot needs to switch from the milling working state to the in-position moving state, the support foot electromagnet 11 is energized, and the hydraulic cylinder telescope 10 extends downward. When the support foot 3 contacts the plane, the magnetic field force generated between the support foot electromagnet 11 and the iron working surface makes the support foot 3 tightly fit the working surface. At this time, the support arm electromagnet 9 is powered off. Through the extension of the hydraulic cylinder telescope 10, the mobile platform 1 and the three support arms 2 are lifted off the working surface. At this time, the working platform 5 is a static platform, and the mobile platform 1 is a dynamic platform with six degrees of freedom. After the mobile platform 1 reaches the position by adjusting, the hydraulic cylinder telescope 10 is lowered, the support arm electromagnet 9 is energized, and the support arm 2 contacts the working surface again. The support foot electromagnet 11 is powered off, and the support foot 3 leaves the working surface. By repeating the above steps, the robot moves to the specified processing position. In addition, the electromagnets on the above support arm 2 and the support foot 3 can be replaced with other adsorption devices, and other adsorption devices that can complete the fastening connection with the surface to be processed also belong to the protection scope of the present invention.

[0027] Specifically, the axis of the first movable pair P1 of each moving branch is perpendicular to the first axis of the first Hooke's joint U1; the second axis of the first Hooke's joint U1 is perpendicular to the axis of the second movable pair P2; the axis of the second movable pair P2 is perpendicular to the first axis of the second Hooke's joint U2; the second axis of the first Hooke's joint U1 is perpendicular to the first axis of the second Hooke's joint U2.

[0028] The present invention is a dual-mode six-degree-of-freedom robot with three motion branches connected in parallel and an end effector having six degrees of freedom. The robot has the advantages of large overall rigidity, walkability, good flexibility, low manufacturing difficulty and low manufacturing cost.

[0029] The above-mentioned preferred embodiments further explain the purpose, technical solutions and advantages of the present invention in detail. It should be understood 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, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. Parallel six-degree-of-freedom mobile in-situ milling robot, characterized by: It includes a working platform, a mobile platform, a milling head and three PUPU motion branches connecting the working platform and the mobile platform, including a milling working state and an in-situ moving state; in the milling working state, the mobile platform is a static platform and the working platform is a dynamic platform; in the in-situ moving state, the mobile platform is a dynamic platform and the working platform is a static platform.

2. The parallel six-degree-of-freedom mobile in-situ milling robot according to claim 1, characterized in that: In the milling working state, its mobile platform is adsorbed on the surface of the part to be processed through the branch chain and remains stationary, and the working platform drives the milling head to work; in the in-place moving state, its working platform is adsorbed on the surface of the part to be processed and remains stationary, and the mobile platform drives the branch chain to adjust the position of the robot, thereby realizing the switching of the robot's milling working state and the in-place moving state.

3. The parallel six-degree-of-freedom mobile in-situ milling robot according to claim 1, characterized in that: In the milling working state, the working platform and the milling head have the ability to move in space with 6 degrees of freedom, and can complete the milling operations of complex surfaces of large structural parts in place; in the on-site moving state, the mobile platform has the ability to move in space with 6 degrees of freedom, and the relative position of the parallel six-degree-of-freedom mobile on-site milling robot on large structural parts can be changed by adjusting the three PUPU motion branches.

4. The parallel six-degree-of-freedom mobile in-situ milling robot according to claim 1, characterized in that: The three PUPU motion branches are successively distributed with a first moving pair, a first Hooke's joint, a second moving pair and a second Hooke's joint from the moving platform to the working platform.

5. The parallel six-degree-of-freedom mobile in-situ milling robot according to claim 4, characterized in that: The axis of the first movable pair is perpendicular to the first axis of the first Hooke's joint; the second axis of the first Hooke's joint is perpendicular to the axis of the second movable pair; the axis of the second movable pair is perpendicular to the first axis of the second Hooke's joint; the second axis of the first Hooke's joint is perpendicular to the second axis of the second Hooke's joint.

6. The parallel six-degree-of-freedom mobile in-situ milling robot according to claim 1, characterized in that: When the robot is in working state, the mobile platform is a static platform. The mobile platform contacts the surface of the part to be processed through three support arms evenly distributed around the circumference. The lower end of the support arm is installed with a first adsorption device. When in the milling working state, the first adsorption device is adsorbed on the surface of the part to be processed, so that the support arm is fastened to the surface of the part to be processed.

7. The parallel six-degree-of-freedom mobile in-situ milling robot according to claim 6, characterized in that: In the milling working state, the working platform is a moving platform with six degrees of freedom, and the milling head is installed in the middle position of the working platform.

8. The parallel six-degree-of-freedom mobile in-situ milling robot according to claim 6, characterized in that: The working platform is equipped with three telescopic devices with the same structure and symmetrical arrangement, and a second adsorption device is installed at the bottom of the telescopic device.

9. The parallel six-degree-of-freedom mobile in-situ milling robot according to claim 8, characterized in that: When the robot switches from the milling working state to the on-site moving state, the telescopic device on the working platform extends downward, and after the bottom of the telescopic device contacts the surface of the part to be processed, the telescopic device is adsorbed on the surface of the part to be processed through the second adsorption device, and then the first adsorption device on the three PUPU motion branches stops adsorbing on the surface of the part to be processed, and the telescopic device continues to extend, so that the three PUPU motion branches leave the working part to be processed, and after adjusting the moving platform to reach the specified position, the telescopic device is lowered, and the first adsorption device on the three PUPU motion branches is adsorbed on the surface of the part to be processed again, and the second adsorption device of the telescopic device stops adsorbing on the working surface of the part to be processed, and the telescopic device leaves the surface of the part to be processed, and the robot moves to the specified processing position by repeating the above steps.

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