A force control based automatic scriber robot system

Abstract

This invention discloses a force-controlled automated scraping robot system, comprising: a camera bracket, a vision camera, a six-degree-of-freedom (6DOF) industrial robot, a worktable, a workpiece, an end effector, a force sensor, and an integrated control system. The vision camera is mounted on top of the camera bracket; the end effector is connected to the 6DOF industrial robot via a six-dimensional force sensor; the workpiece is placed on the worktable, located below the vision camera; the integrated control system is connected to the vision camera, the 6DOF industrial robot, and the end effector. The integrated control system performs regional analysis on images captured by the vision camera to obtain regional coordinates, plans the robot's motion trajectory based on these coordinates, and controls the end effector and the 6DOF industrial robot to coordinate their movements to scrape the workpiece. This invention replaces manual scraping, enabling precision machining of various high-precision structural components on spacecraft surfaces.

Description

Technical Field

[0001] This invention belongs to the field of ultra-precision machining technology, and in particular relates to an automatic scraping robot system based on force control. Background Technology

[0002] In the development of aerospace optical remote sensors, in order to reduce the impact of sensor assembly stress on system accuracy and achieve precise optical path transmission, the connection surfaces of precision parts such as remote sensor optical element frames, main load-bearing structural components, traditional mechanism parts, and space pointing structural components have high precision, generally at the micrometer level.

[0003] To achieve the high surface accuracy of the aforementioned parts, manual scraping is generally used in production. Traditional manual scraping involves first cleaning the part surface, applying red lead powder to the end face, then grinding the end face against a standard plane to identify high points. These high points are then removed using a scraping tool, and the surface accuracy is achieved through repeated processes. Therefore, traditional manual scraping is inefficient, unsuitable for large structural parts, and highly dependent on manual skill and physical strength. Prolonged manual scraping can easily lead to occupational diseases for workers. Furthermore, due to inconsistent scraping skill levels, the quality of the scraped parts is unstable.

[0004] With the development of remote sensing technology, optical remote sensors are becoming larger, lighter, and more stable, leading to increasingly larger, more complex, and more precise structural components. Traditional manual scraping methods for precision machining of large structural components have limitations, such as difficulties in identifying high and low points, self-inspection, and removing high points, making it impossible to perform scraping on large structural components. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide an automatic scraping robot system based on force control to replace manual scraping and realize precision machining of the surface of various high-precision structural parts of spacecraft.

[0006] The objective of this invention is achieved through the following technical solution: an automatic scraping robot system based on force control, comprising: a camera bracket, a vision camera, a six-degree-of-freedom industrial robot, a worktable, a workpiece, an end effector, a force sensor, and an integrated control system; wherein, the vision camera is disposed on the top of the camera bracket; the end effector is connected to the six-degree-of-freedom industrial robot through the six-dimensional force sensor; the workpiece is disposed on the worktable; the workpiece is located below the vision camera; the integrated control system is connected to the vision camera, the six-degree-of-freedom industrial robot, and the end effector respectively; the integrated control system performs regional analysis on the images captured by the vision camera to obtain regional coordinates, obtains robot motion trajectory planning based on the regional coordinates, and controls the end effector and the six-degree-of-freedom industrial robot to move collaboratively to scrape the workpiece according to the robot motion trajectory planning.

[0007] In the aforementioned force-controlled automatic scraping robot system, the integrated control system includes a scraping area analysis module, a scraping trajectory planning module, and a cooperative motion control module. The scraping area analysis module analyzes images captured by a vision camera, identifies area coordinates, and transmits these coordinates to the scraping trajectory planning module. The scraping trajectory planning module receives the area coordinates, generates a robot motion trajectory plan based on these coordinates, and transmits the robot motion trajectory plan to the cooperative motion control module. The cooperative motion control module receives the robot motion trajectory plan and controls the end effector to coordinate with the six-degree-of-freedom industrial robot to scrape the workpiece.

[0008] In the aforementioned force-controlled automatic scraping robot system, the vision camera takes pictures of the workpiece after it has been coated with red lead powder and is now being scraped.

[0009] In the aforementioned force-controlled automatic scraping robot system, the six-degree-of-freedom industrial robot is used to fix the end effector and move in coordination with the end effector to scrape the area of ​​the workpiece to be scraped.

[0010] In the above-mentioned force-controlled automatic scraping robot system, the worktable is equipped with a positioning device, which can extract the coordinate position of the workpiece.

[0011] In the aforementioned force-controlled automatic scraping robot system, the end effector is equipped with a scraper.

[0012] In the aforementioned force-controlled automatic scraping robot system, the force loading device and angle adjustment device of the end effector drive the scraper to load the workpiece surface at a preset angle. When the loading force reaches the set value, it drives the six-degree-of-freedom industrial robot to perform scraping action.

[0013] In the aforementioned force-controlled automatic scraping robot system, the force sensor monitors the applied force on the scraper.

[0014] A method for automatic scraping using a force-controlled automatic scraping robot system includes: clamping a workpiece onto a worktable; uniformly applying red lead powder to the surface of the workpiece; using a reference plate to scrape the surface of the workpiece, wherein the area where the red lead powder is removed by grinding is a high-point area; taking pictures of the workpiece surface with a vision camera and transmitting the pictures to an integrated control system; the scraping area analysis module of the integrated control system performing area analysis on the pictures taken by the vision camera, identifying high-point areas, and extracting the coordinate values ​​of the high-point areas; the scraping trajectory planning module of the integrated control system generating a robot motion trajectory plan based on the scraping trajectory planning module; and the cooperative motion control module of the integrated control system controlling the end effector and the six-degree-of-freedom industrial robot to perform cooperative motion to scrape the workpiece based on the robot motion trajectory plan.

[0015] In the aforementioned automatic scraping method, the collaborative motion control module of the integrated control system controls the end effector and the six-degree-of-freedom industrial robot to perform collaborative motion scraping on the workpiece according to the robot motion trajectory planning. This includes: placing the scraper at the starting point of the scraping program; setting the angle between the scraper and the workpiece, the single scraping speed of the scraper, and the pressure value between the scraper and the workpiece according to the robot motion trajectory planning; adjusting the contact angle between the scraper and the workpiece and applying a downward displacement through the drive device in the end effector according to the angle between the scraper and the workpiece until the scraper contacts the workpiece; after the force sensor collects the scraper loading force and reaches the pressure value between the scraper and the workpiece, issuing a motion command to the six-degree-of-freedom industrial robot; the six-degree-of-freedom robot executes all single scraping segments according to the robot motion trajectory planning at the single scraping speed of the scraper, and all single scraping segments are connected in series to form the robot motion trajectory. The six-degree-of-freedom robot needs to be lifted after completing a single scraping segment.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] (1) This invention is used to realize parameterized control of the scraping process, replace manual scraping, and realize precision machining of the surface of various high-precision structural parts of spacecraft;

[0018] (2) The present invention solves the process limitations of traditional manual scraping, such as difficulty in identifying high and low points, difficulty in self-inspection, and difficulty in removing high points. Attached Figure Description

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0020] Figure 1 This is a structural schematic diagram of the force-controlled automatic scraping robot system provided in an embodiment of the present invention;

[0021] Figure 2 This is a flowchart of the automatic scraping method of the automatic scraping robot system provided in the embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the workpiece grinding process provided in an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the robot's motion trajectory provided in an embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of the single-cycle scraper robot blade movement trajectory provided in an embodiment of the present invention. Detailed Implementation

[0025] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] Figure 1 This is a structural schematic diagram of the force-controlled automatic scraping robot system provided in an embodiment of the present invention. Figure 1 As shown, the force-controlled automatic scraping robot system includes: a camera bracket 1, a vision camera 2, a six-degree-of-freedom industrial robot 3, a worktable 4, a workpiece 5, an end effector 6, a force sensor 7, and an integrated control system. The vision camera 2 is mounted on top of the camera bracket 1. The end effector 6 is connected to the six-degree-of-freedom industrial robot 3 via the six-dimensional force sensor 7. The workpiece 5 is placed on the worktable 4, located below the vision camera 2. The integrated control system is connected to the vision camera 2, the six-degree-of-freedom industrial robot 3, and the end effector 6. The integrated control system performs regional analysis on the images captured by the vision camera to obtain regional coordinates, plans the robot's motion trajectory based on the regional coordinates, and controls the end effector and the six-degree-of-freedom industrial robot to move collaboratively to scrape the workpiece 5.

[0027] The integrated control system includes a scraping area analysis module, a scraping trajectory planning module, and a cooperative motion control module. The scraping area analysis module analyzes images captured by a vision camera, identifies the area coordinates, and transmits these coordinates to the scraping trajectory planning module. The scraping trajectory planning module receives the area coordinates, generates a robot motion trajectory plan based on these coordinates, and transmits the robot motion trajectory plan to the cooperative motion control module. The cooperative motion control module receives the robot motion trajectory plan and controls the end effector to coordinate with the six-degree-of-freedom industrial robot to scrape the workpiece 5.

[0028] Camera mount 1: Provides stable support for the vision camera system.

[0029] Vision camera 2: Takes pictures of the workpiece after grinding following the application of red lead powder, and collects data.

[0030] Six-DOF industrial robot 3: Used to fix the end effector and move in coordination with the end effector to scrape the area of ​​the workpiece to be scraped.

[0031] Worktable 5: Used for workpiece clamping. A positioning device is installed on the worktable to assist in the conversion of workpiece coordinates to the coordinates of the robotic scraping equipment.

[0032] End effector 7: The end effector is equipped with a scraper. The scraper is driven by the force loading device and angle adjustment device in the end effector to load the surface of the part at a certain angle. When the loading force reaches the set value, the robot is driven to perform a scraping action.

[0033] Force sensor 8: Monitors the loading force on the robot's scraper blade.

[0034] like Figure 2 As shown in the figure, this embodiment also provides a method for automatic scraping using a force-controlled automatic scraping robot system, the method comprising:

[0035] Clamp workpiece 5 onto worktable 4;

[0036] Apply red lead powder evenly to the surface of workpiece 5, and use a reference plate to grind the surface of workpiece 5 to be scraped. The area where the red lead powder is removed by grinding is the high point area.

[0037] The vision camera 2 takes pictures of the workpiece surface and transmits the pictures to the integrated control system;

[0038] The scraping area analysis module of the integrated control system performs area analysis on the photos taken by the vision camera, identifies high point areas, and extracts the coordinate values ​​of the high point areas;

[0039] The scraping trajectory planning module of the integrated control system generates the robot motion trajectory plan based on the scraping trajectory planning module.

[0040] The integrated control system's collaborative motion control module plans and controls the end effector to coordinate motion with the six-degree-of-freedom industrial robot based on the robot's motion trajectory, and scrapes the workpiece 5.

[0041] The integrated control system's collaborative motion control module plans and controls the end effector to coordinate motion with the six-degree-of-freedom industrial robot based on the robot's motion trajectory, performing scraping on workpiece 5, including:

[0042] Place the scraper at the starting point of the scraping process, and set the angle between the scraper and the workpiece, the single scraping speed of the scraper, and the pressure value between the scraper and the workpiece according to the robot's motion trajectory.

[0043] The drive unit in the end effector adjusts the contact angle between the scraper and the workpiece according to the angle between the scraper and the workpiece, and applies downward displacement until the scraper contacts the workpiece.

[0044] Once the force sensor detects the applied force on the scraper and reaches the pressure value between the scraper and the workpiece, it sends motion commands to the six-degree-of-freedom industrial robot.

[0045] The six-degree-of-freedom robot executes all single-scraping segments at the speed of a single scraping motion of the scraper according to the robot's motion trajectory planning. All single scraping segments are connected in series to form the robot's motion trajectory. The six-degree-of-freedom robot needs to be lifted after completing a single scraping segment.

[0046] Specifically, the method includes the following steps:

[0047] Step 1, workpiece clamping: Clamp the part to be scraped onto the worktable, and take measures such as raising it to control the distance between the surface of the part and the vision camera within a certain range, so that the vision camera can focus and take pictures.

[0048] Step 2, apply red lead powder: as follows Figure 3 As shown, red lead powder is evenly applied to the surface of the workpiece, and the surface to be scraped is evenly and completely covered.

[0049] Step 3, workpiece grinding: such as Figure 3 As shown, a reference plate is used to grind the surface to be scraped. The area where the red lead powder is removed by grinding is the high point area.

[0050] Step 4, Visual Photography: The vision system takes pictures of the workpiece surface;

[0051] Step 5, Analysis of the area to be scraped: Using the scraping area analysis module in the control system, the photos are compared and analyzed based on the color database to identify high point areas and extract the coordinate values ​​of the high point areas;

[0052] Step 6, Robot scraping trajectory planning: The scraping trajectory planning module in the control system analyzes the coordinate values ​​obtained in Step 5 for high-point areas and automatically generates the robot's motion trajectory, such as... Figure 4 As shown, the robot's scraping motion trajectory consists of several single scraping segments.

[0053] Step 7, Tool Positioning: Execute the tool positioning program in the robot scraping process, place the scraping tool at the starting point of the scraping program, and simultaneously set the robot scraping process parameters, including the angle between the scraper and the workpiece, the single scraping speed of the scraper, and the pressure value between the scraper and the workpiece.

[0054] Step 8, end effector pressing down: Adjust the contact angle between the scraping tool and the workpiece by the drive device in the end effector and apply the pressing section displacement until the tool contacts the workpiece;

[0055] Step 9, the scraper blade is subjected to a set force: after the six-dimensional force sensor collects the applied force and the set value is reached, a motion command is sent to the robot;

[0056] Step 10, Robotic Scraping: The six-degree-of-freedom robot performs a single scraping segment motion until the scraping segment is completed and the robot is lifted. The single-point scraping trajectory is as follows: Figure 5 All single scraping sections are connected in series to form an attached... Figure 4 The robot's movement trajectory is shown in the image; once the entire trajectory is completed, the scraping operation is finished.

[0057] Then repeat steps 2-5 to check if the requirements are met. If not, continue scraping until the requirements are met, then end the scraping work.

[0058] This embodiment establishes an integrated robotic scraping system that includes detection, high and low point identification, scraping pressure control, automatic trajectory planning, and execution of the scraping process, thereby achieving full automation of the scraping process.

[0059] This embodiment enables rapid identification of high-point areas by setting up an online visual inspection system.

[0060] This embodiment integrates an end effector, which allows setting process parameters such as scraper angle, scraper movement speed, and scraper pressure, thus realizing parametric control of the scraping process and eliminating the influence of the inherent cumulative error of the multi-joint motion of the six-degree-of-freedom process robot on the accuracy of the scraping process.

[0061] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A force-controlled automated scraping robot system, characterized in that... include: Camera bracket (1), vision camera (2), six-degree-of-freedom industrial robot (3), worktable (4), workpiece (5), end effector (6), six-dimensional force sensor (7), and integrated control system; among which, The visual camera (2) is mounted on top of the camera bracket (1); The end effector (6) is connected to the six-degree-of-freedom industrial robot (3) via the six-dimensional force sensor (7); The workpiece (5) is placed on the worktable (4); The workpiece (5) is located below the vision camera (2); The integrated control system is connected to the vision camera (2), the six-degree-of-freedom industrial robot (3), and the end effector (6), respectively; The integrated control system performs regional analysis on the photos taken by the vision camera to obtain regional coordinates, and obtains robot motion trajectory planning based on the regional coordinates. Based on the robot motion trajectory planning, it controls the end effector to coordinate with the six-degree-of-freedom industrial robot to scrape the workpiece (5). The integrated control system includes a scraping area analysis module, a scraping trajectory planning module, and a cooperative motion control module; wherein... The scraping area analysis module performs area analysis on the photos taken by the visual camera, identifies the area coordinates, and transmits the area coordinates to the scraping trajectory planning module. The scraping trajectory planning module receives the area coordinates, generates the robot motion trajectory plan based on the area coordinates, and transmits the robot motion trajectory plan to the cooperative motion control module. The collaborative motion control module receives the robot's motion trajectory plan and controls the end effector to coordinate with the six-degree-of-freedom industrial robot to scrape the workpiece (5) according to the robot's motion trajectory plan. The vision camera (2) takes pictures of the workpiece after it has been coated with red lead powder and is being polished. The worktable is equipped with a positioning device, which is capable of extracting the coordinate position of the workpiece; The end effector is provided with a scraper at its end; The force loading device and angle adjustment device of the end effector drive the scraper to load the workpiece surface at a preset angle. When the loading force reaches the set value, it drives the six-degree-of-freedom industrial robot to perform scraping action.

2. The force-controlled automatic scraping robot system according to claim 1, characterized in that: The six-degree-of-freedom industrial robot (3) is used to fix the end effector and move in coordination with the end effector to scrape the area of ​​the workpiece to be scraped.

3. The force-controlled automatic scraping robot system according to claim 1, characterized in that: The six-dimensional force sensor (7) monitors the loading force of the scraper.

4. A method for automatic scraping using a force-controlled automatic scraping robot system according to any one of claims 1-3, characterized in that... include: Clamp the workpiece (5) onto the worktable (4); Apply red lead powder evenly to the surface of the workpiece (5), and use a reference plate to grind the surface of the workpiece (5) to be scraped. The area where the red lead powder is removed by grinding is the high point area. The vision camera (2) takes pictures of the workpiece surface and transmits the pictures to the integrated control system; The scraping area analysis module of the integrated control system performs area analysis on the photos taken by the vision camera, identifies high point areas, and extracts the coordinate values ​​of the high point areas; The scraping trajectory planning module of the integrated control system generates the robot motion trajectory plan based on the scraping trajectory planning module. The integrated control system’s collaborative motion control module plans and controls the end effector to coordinate motion with the six-degree-of-freedom industrial robot according to the robot’s motion trajectory, and scrapes the workpiece (5).

5. The automatic scraping method according to claim 4, characterized in that: The integrated control system's collaborative motion control module plans and controls the end effector to coordinate motion with the six-degree-of-freedom industrial robot based on the robot's motion trajectory, performing scraping on the workpiece (5) including: Place the scraper at the starting point of the scraping process, and set the angle between the scraper and the workpiece, the single scraping speed of the scraper, and the pressure value between the scraper and the workpiece according to the robot's motion trajectory. The drive unit in the end effector adjusts the contact angle between the scraper and the workpiece according to the angle between the scraper and the workpiece, and applies downward displacement until the scraper contacts the workpiece. Once the force sensor detects the applied force on the scraper and reaches the pressure value between the scraper and the workpiece, it sends motion commands to the six-degree-of-freedom industrial robot. The six-degree-of-freedom robot executes all single-scraping segments at the speed of a single scraping motion of the scraper according to the robot's motion trajectory planning. All single scraping segments are connected in series to form the robot's motion trajectory. The six-degree-of-freedom robot needs to be lifted after completing a single scraping segment.

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