Trajectory reproduction device and reproduction method

Abstract

The application discloses a track reproduction device and a reproduction method, which comprise a mounting frame, a polishing head, a handle, a six-dimensional force sensor, a six-axis sensor and a wire position acquisition mechanism; the mounting frame, the polishing head and the handle are arranged, and track data is generated by cooperating with offline programming software, so that when the track is reproduced, manual dragging of a teaching robot is not needed, and the polishing process can be completed only by manually dragging the polishing head on the mounting frame, the polishing method is more free during track reproduction, and the track reproduction is more accurate; and the six-dimensional force sensor, the six-axis sensor and the wire position acquisition mechanism are cooperated, the posture and the track during the polishing process can be read, the force and the torque in different directions can be read by the six-dimensional force sensor, the accuracy of the polishing process of the robot can be ensured by combining the force during the track reproduction process, and the polishing effect of the robot is better.

Description

Technical Field

[0001] The present invention relates to the field of robot automated processing technology, and in particular to a trajectory reproduction device and reproduction method. Background Art

[0002] Grinding is a surface modification technique that generally involves using a rough object (such as sandpaper containing high-hardness particles) to change the physical properties of a material's surface through friction. The primary goal is to achieve a specific surface roughness. In processes like grinding and spraying, manual labor and a robotic arm must first replicate the machining path, followed by the robot independently completing the subsequent processing.

[0003] The existing trajectory reproduction method involves manually dragging a teaching robot through a machining process and having the teaching robot record the trajectory. This requires human-machine coordination when dragging the teaching robot, and the robot's six-axis motors generate torque coupling, which is inconsistent with human perception. Therefore, the force used to drag the robot cannot be controlled, resulting in a limited freedom in the dragging of the teaching robot during grinding. Furthermore, the existing teaching robot can only record the route and cannot read the grinding force. This means that during grinding, only the grinding trajectory can be reproduced, not the grinding force, which affects the robot's grinding effect. Therefore, it is necessary to further improve the existing trajectory reproduction method. Summary of the Invention

[0004] In view of this, the present invention aims to address the deficiencies in the prior art, and its main purpose is to provide a trajectory reproduction device and a reproduction method, which can effectively solve the problems of the existing trajectory reproduction method, such as the uncontrollable force of dragging the teaching robot, the inability to read the magnitude of the grinding force, and the impact on the robot's grinding effect.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A trajectory reproduction device includes a mounting frame, a grinding head, a handle, a six-dimensional force sensor, a six-axis sensor and a wire position acquisition mechanism; the grinding head is arranged at one end of the mounting frame; the handle is arranged at the other end of the mounting frame; the six-dimensional force sensor and the six-axis sensor are clamped in sequence between the mounting frame and the handle; the wire position acquisition mechanism is arranged on the handle, and the wire position acquisition mechanism includes a wire distance sensor assembly, a first encoder and a second encoder, one end of the wire distance sensor assembly is connected to the handle through an elastically retractable wire and hangs below the handle; the first encoder and the second encoder are both arranged on the wire distance sensor assembly and sense its rotation angle in different directions.

[0007] As a preferred solution, the first encoder is extended vertically, and the second encoder is extended horizontally.

[0008] As a preferred solution, the pull-wire distance sensor assembly includes a pull-wire box and a distance sensor. One end of the pull-wire box is connected to the handle through a pull wire and hangs below the handle. The distance sensor is arranged on the pull-wire box.

[0009] As a preferred solution, the handle is provided with a button that connects the six-dimensional force sensor, the six-axis sensor and the wire position acquisition mechanism.

[0010] A reproduction method using a trajectory reproduction device comprises the following steps:

[0011] (1) Manually hold the handle and use the grinding head to grind the existing shape of the product on the grinder as needed;

[0012] (2) Data is collected during the grinding process through a six-dimensional force sensor, a six-axis sensor, a wire-drawing distance sensor assembly, a first encoder, and a second encoder, wherein the six-dimensional force sensor is used to measure forces in three directions (Fx, Fy, Fz) and moments in three directions (Mx, My, Mz); the first encoder is used to read the rotation angle, and the second encoder is used to read the pitch angle; the wire-drawing distance sensor assembly is used to read the length of the wire; thereby calculating the coordinates in space; the six-axis sensor is used to measure the linear acceleration and angular velocity during the grinding process, thereby sensing the overall posture changes;

[0013] (3) Importing the generated trajectory data into the offline programming software;

[0014] (4) Import the trajectory data generated by the offline programming software into the robot.

[0015] As a preferred solution, before starting step (1), the six-dimensional force sensor, the six-axis sensor, the wire-type distance sensor assembly, the first encoder and the second encoder need to be zeroed.

[0016] As a priority solution, when programming in step (3), the trajectories that are usable without interference and non-singular points are checked and retained, and the unusable ones are eliminated.

[0017] As a preferred solution, after step (4) is completed, the collected force value is used for force calibration: guided by the force, the robot reproduces the trajectory, and the manual grinding times, force, and posture are slightly adjusted to adapt to and approach the grinding force value at the same position.

[0018] As a priority solution, the complete parameters of multiple force calibrations are used to ensure that the robot can quickly adjust the grinding force during the grinding process and make corresponding adjustments to the force based on existing data.

[0019] Compared with the prior art, the present application has obvious advantages and beneficial effects, specifically, from the above technical solution, it can be known that:

[0020] By setting the mounting rack, polishing head and handle, and cooperating with the use of offline programming software to generate trajectory data, when the polishing trajectory is reproduced, manual dragging of the teaching robot is not required, and only the polishing head on the mounting rack needs to be manually dragged to complete the polishing process, so that the polishing method during trajectory reproduction is more free, and the reproduction of the polishing trajectory is also more accurate; and cooperating with the six-dimensional force sensor, six-axis sensor and wire position acquisition mechanism, not only the posture and trajectory during the polishing process can be read, but also the force and torque in different directions can be read through the six-dimensional force sensor, so that the accuracy of the robot polishing process can be ensured during the trajectory reproduction process by combining the force, and the polishing effect of the robot is also better.

[0021] To more clearly set forth the structural features and effects of the present application, the present application will be described in detail below in combination with the drawings and specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0022] Fig. 1 is a schematic diagram of the three-dimensional structure of the trajectory reproduction device in the preferred embodiment of the present application;

[0023] Fig. 2 is a flowchart of the trajectory reproduction method in the preferred embodiment of the present application.

[0024] BRIEF DESCRIPTION OF DRAWINGS

[0025] 10, mounting rack 20, polishing head

[0026] 30, handle 40, six-dimensional force sensor

[0027] 50, six-axis sensor 60, wire position acquisition mechanism

[0028] 61, wire distance sensor assembly 611, wire

[0029] 612, wire box 613, distance sensor

[0030] 62, first encoder 63, second encoder DETAILED DESCRIPTION

[0031] Please refer to Figs. 1-2 , which shows the specific structure of the preferred embodiment of the present application, which includes mounting rack 10, polishing head 20, handle 30, six-dimensional force sensor 40, six-axis sensor 50 and wire position acquisition mechanism 60.

[0032] The polishing head 20 is arranged at one end of the mounting rack 10.

[0033] The handle 30 is arranged at the other end of the mounting frame 10, and the human hand holds the handle 30 to drive the polishing head 20 to complete the polishing process when polishing.

[0034] The six-dimensional force sensor 40 and the six-axis sensor 50 are sequentially clamped between the mounting frame 10 and the handle 30; the six-axis sensor 50, also known as a 6 degree of freedom (6DoF) sensor or an inertial measurement unit (IMU), generally includes three accelerometers and three gyroscopes. The accelerometer is used to measure the linear acceleration of the object in three-dimensional space, and the gyroscope is used to measure the angular velocity of the object in three-dimensional space. By combining the data of the two sensors, the attitude position and velocity information of the object in three-dimensional space can be obtained. The six-dimensional force sensor 40 mainly measures the force and torque of the object in three-dimensional space through the deformation of the internal elastic body under force, and converts the force / torque signal into an electrical signal output.

[0035] The pull wire position acquisition mechanism 60 is arranged on the handle 30, and the pull wire position acquisition mechanism 60 includes a pull wire distance sensor assembly 61, a first encoder 62, and a second encoder 63. One end of the pull wire distance sensor assembly 61 is connected to the handle 30 through an elastically recoverable pull wire 611 and is perpendicular below the handle 30, wherein the pull wire 611 on the pull wire distance sensor assembly 61 is in a tension state; the first encoder 62 and the second encoder 63 are both arranged on the pull wire distance sensor assembly 61 and sense the rotation angles in different directions. In this embodiment, the first encoder 62 is arranged vertically, and the second encoder 63 is arranged horizontally; the first encoder 62 is used to sense the rotation angle in the horizontal direction during polishing, and the second encoder 63 is used to sense the pitch angle in the vertical direction during polishing. The pull wire distance sensor assembly 61 includes a pull wire box 612 and a distance sensor 613. One end of the pull wire box 612 is connected to the handle 30 through the pull wire 611 and is perpendicular below the handle 30. The distance sensor 613 is arranged on the pull wire box 612, and the distance sensor 613 is used to sense the distance of the pull wire 611. The handle 30 is provided with a button connected to the six-dimensional force sensor 40, the six-axis sensor 50, and the pull wire position acquisition mechanism 60, which facilitates the calibration and recording of data during manual polishing.

[0036] The steps of the reproduction method in this embodiment are as follows:

[0037] (1) The human hand holds the handle, and the existing shape of the product on the polisher is polished as needed by the polishing head; in this embodiment, the six-dimensional force sensor, the six-axis sensor, the pull wire distance sensor assembly, the first encoder, and the second encoder need to be zeroed before the step (1) starts.

[0038] (2) Data is collected during the grinding process through a six-dimensional force sensor, a six-axis sensor, a wire-drawing distance sensor assembly, a first encoder, and a second encoder, wherein the six-dimensional force sensor is used to measure forces in three directions (Fx, Fy, Fz) and moments in three directions (Mx, My, Mz); the first encoder is used to read the rotation angle, and the second encoder is used to read the pitch angle; the wire-drawing distance sensor assembly is used to read the length of the wire; thereby calculating the coordinates in space; the six-axis sensor is used to measure the linear acceleration and angular velocity during the grinding process, thereby sensing the overall posture changes;

[0039] (3) Importing the generated trajectory data into the offline programming software; in this embodiment, when programming in step (3), the usable trajectories that do not interfere with or have non-singular points are checked and retained, while the unusable ones are eliminated. This prevents the subsequent robot from interfering with the outside world during the execution of the reproduced trajectory.

[0040] (4) Import the trajectory data generated by the offline programming software into the robot. In this embodiment, after step (4) is completed, the collected force value is used to perform force calibration: guided by the force, the trajectory is reproduced by the robot, and the number of manual grindings, force, posture, and polishing posture are slightly adjusted to adapt to and approach the grinding force value at the same position. Through the complete parameters of multiple force calibrations, it is ensured that the robot can quickly adjust the grinding force during the grinding process, and make corresponding adjustments to the force with reference to the existing data. During calibration, compensation processing is performed through the six-dimensional force sensor in the robot. Through multiple force calibrations, the accuracy of the robot grinding is made higher.

[0041] The design focus of the present invention is that by providing a mounting frame, a grinding head, and a handle, and using offline programming software to generate trajectory data, there is no need to manually drag the teaching robot when reproducing the grinding trajectory. The grinding process can be completed by manually dragging the grinding head on the mounting frame, so that the grinding method during trajectory reproduction is more free and the reproduction of the grinding trajectory is more accurate; and in conjunction with a six-dimensional force sensor, a six-axis sensor and a wire position acquisition mechanism, not only can the posture and trajectory during the grinding process be read, but also the force and torque in different directions can be read through the six-dimensional force sensor, so that the force can be combined in the trajectory reproduction process to ensure the accuracy of the robot grinding process, so that the robot's grinding effect is also better.

[0042] The above description is merely a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any minor modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A trajectory reproduction device, characterized in that: It includes a mounting frame, a grinding head, a handle, a six-dimensional force sensor, a six-axis sensor and a wire position acquisition mechanism; the grinding head is arranged at one end of the mounting frame; the handle is arranged at the other end of the mounting frame; the six-dimensional force sensor is used to measure forces in three directions (Fx, Fy, Fz) and moments in three directions (Mx, My, Mz), and the six-axis sensor is used to measure linear acceleration and angular velocity during the grinding process, and the six-dimensional force sensor and the six-axis sensor are clamped between the mounting frame and the handle in sequence; the wire position acquisition mechanism is arranged on the handle, and the wire position acquisition mechanism includes a wire distance sensor assembly, a first encoder and a second encoder, the wire distance sensor assembly is used to read the length of the wire, and one end of the wire distance sensor assembly is connected to the handle through an elastically retractable wire and hangs below the handle; the first encoder and the second encoder are both arranged on the wire distance sensor assembly and sense its rotation angle in different directions.

2. The trajectory reproduction device according to claim 1, characterized in that: The first encoder is extended vertically, and the second encoder is extended horizontally.

3. The trajectory reproduction device according to claim 1, characterized in that: The pull-wire type distance sensor assembly includes a pull-wire box and a distance sensor. One end of the pull-wire box is connected to the handle through a pull wire and hangs below the handle. The distance sensor is arranged on the pull-wire box.

4. The trajectory reproduction device according to claim 1, characterized in that: The handle is provided with a button which is connected to the six-dimensional force sensor, the six-axis sensor and the wire position acquisition mechanism.

5. A reproduction method using the trajectory reproduction device according to any one of claims 1 to 4, characterized in that: The following steps are included: (1) Manually hold the handle and use the grinding head to grind the existing shape of the product on the grinder as needed; (2) Data is collected during the grinding process through a six-dimensional force sensor, a six-axis sensor, a wire-drawn distance sensor assembly, a first encoder, and a second encoder. The six-dimensional force sensor is used to measure forces in three directions (Fx, Fy, Fz) and moments in three directions (Mx, My, Mz); the first encoder is used to read the rotation angle, and the second encoder is used to read the pitch angle; the wire-drawn distance sensor assembly is used to read the length of the wire; thereby calculating the coordinates in space; the six-axis sensor is used to measure the linear acceleration and angular velocity during the grinding process, thereby sensing the overall posture changes; (3) Import the generated trajectory data into the offline programming software; (4) Import the trajectory data generated by the offline programming software into the robot.

6. The reproduction method according to claim 5, wherein: Before starting step (1), the six-dimensional force sensor, the six-axis sensor, the wire-type distance sensor assembly, the first encoder, and the second encoder need to be zeroed.

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