Six-degree-of-freedom parallel robot dragging teaching system based on three-dimensional mouse

Abstract

The invention discloses a dragging teaching system of a six-degree-of-freedom parallel robot. The wireless three-dimensional mouse is connected with a computer through a wireless receiver, the computer is connected with a robot control system, and the robot control system is connected with joint motors. The implementation method of the system comprises the steps that an operator applies force and torque on the wireless three-dimensional mouse, and an upper computer system in a computer reads data of the wireless three-dimensional mouse, processes the data into control signals of the six-degree-of-freedom parallel robot and sends the control signals to a robot control system; therefore, the moving platform of the six-degree-of-freedom parallel robot is controlled to move according to the control intention of an operator, dragging of the moving platform of the six-degree-of-freedom parallel robot is achieved, and after dragging is completed, a track reproduction file can be generated and used for reproducing a teaching track. According to the dragging teaching system, the control process of the six-degree-of-freedom parallel robot can be more visual, operation is more convenient, and the teaching efficiency is high.

Description

Technical Field

[0001] The present invention relates to the technical field of robot control, and particularly relates to a teaching-by-dragging control system for a six-degree-of-freedom parallel robot. Background Art

[0002] With the rapid development of industrial automation and robot technology, six-degree-of-freedom parallel robots are increasingly widely used in fields such as precision manufacturing, assembly, and operation. To enable industrial robots to complete various operation tasks as required, the teaching process is essential. Traditional teaching techniques are generally divided into teaching by a teach pendant and off-line programming teaching. Teaching by a teach pendant usually relies on dedicated hardware devices. The operator manually guides the robot to each coordinate point through the control device for teaching, which is suitable for static scenarios but has poor flexibility in dynamic environments. Off-line teaching is to perform robot path planning and task setting through a simulation system in a computer environment. Although it has high flexibility, it also relies on fixed devices and has high technical requirements for the operator. No matter which method is used, it poses high requirements for the technical level of the operator and the configuration of the device, and the operation process is complex, with poor flexibility and difficulty in adapting to changing working environments.

[0003] With the development of technology, the teaching-by-dragging technique has gradually become an effective means to overcome the limitations of traditional teaching methods. Through the interaction between humans and robots, the operator can more intuitively convey their intentions, and the robot makes real-time adjustments according to the actions and instructions of the operator. This human-robot collaboration mode not only improves the flexibility of operation, reduces the requirements for the technical level of the operator, but also demonstrates remarkable real-time performance and high precision when performing complex trajectories and coping with dynamically changing tasks, greatly improving work efficiency.

[0004] In the method of teaching a robot by dragging in human-robot interaction, existing methods mainly include a fast teaching method based on a force sensor and a teaching-by-dragging method without a force sensor based on dynamics. For the fast teaching method based on a force sensor, the operator controls the robot's actions by applying forces and torques to a six-axis force sensor installed on the robot flange to achieve real-time and precise teaching by dragging. However, due to the high cost of the six-axis force sensor and the limitations of close-range operation, the flexibility and scalability of this method are limited in actual application scenarios.

[0005] In contrast, the dynamic-based powerless sensor dragging teaching method realizes robot control by establishing an accurate dynamic model, friction model of the robot, and estimating external torque. The advantage of this method lies in its low hardware cost, avoiding the use of expensive force sensors. However, it is very difficult to construct an accurate dynamic model of a parallel robot and establish an accurate friction model. It has poor versatility and high requirements for computing power and control accuracy, requiring a higher controller authority and efficient real-time computing ability, which poses certain challenges in the application process of this method. Summary of the Invention

[0006] Aiming at the deficiencies of the above technologies, the purpose of the present invention is to overcome the shortcomings of the prior art and provide a parallel robot dragging teaching system with low operation threshold, simple implementation, low cost, intuitive control effect, and safe and remote control.

[0007] To achieve the above purpose, the technical solution adopted by the present invention is: a dragging teaching system for a six-degree-of-freedom parallel robot, including a six-degree-of-freedom parallel robot, a robot control system, a wireless 3D mouse, a computer, and a host computer system; the six-degree-of-freedom parallel robot includes a static platform, a moving platform, and six motion chains connecting the two, and each chain is driven by a joint servo motor; the robot control system communicates with the computer through the real-time Ethernet protocol (EtherCAT), receives control instructions, and drives the joint servo motors to make the moving platform move according to the operation intention; the wireless 3D mouse is connected to the computer through a wireless receiver and is used to collect six-degree-of-freedom force / torque signals applied by the operator. Its coordinate system is dynamically mapped to the coordinate system of the center of the moving platform, and the mapping relationship is: the +X axis of the moving platform corresponds to its +Y axis, the +Y axis of the moving platform corresponds to its +X axis, and the +Z axis of the moving platform corresponds to its -Z axis; the computer and the host computer system are used to read the six-dimensional data of the wireless 3D mouse in real time to generate control instructions, record the information of the moving platform, and generate a reproduction trajectory program.

[0008] Furthermore, the wireless 3D mouse is fixed on the moving platform of the six-degree-of-freedom parallel robot to intuitively drag the robot for teaching, or it can be detached from the parallel robot and placed on the desktop for remote dragging teaching.

[0009] Furthermore, the host computer system in the computer includes an interaction function area, a data processing module, and a trajectory generation module; the interaction function area includes buttons for turning on and off the data processing module, buttons for turning on and off the trajectory generation module, a slider for adjusting the robot dragging speed at any time, and other buttons for interacting with the control system; the data processing module calls functions in the hidapi library to read the six-dimensional data of the wireless 3D mouse in real time, calibrates the data into force information, maps it into motion control instructions through the admittance model, communicates with the lower computer, and sends control instructions; the trajectory generation module is used to communicate with the lower computer, receive and record the pose, speed, and acceleration data information transmitted by the control system, re-plan and interpolate based on the recorded path points, and automatically generate a motion program for reproducing the teaching trajectory.

[0010] The beneficial effects of the present invention are as follows:

[0011] The dragging teaching system of the present invention can realize the dragging of the six-degree-of-freedom parallel robot by applying force and torque to the wireless 3D mouse, without using expensive force sensors, and has a low usage cost; it can be based on the existing control system, without establishing complex dynamic models and friction models, has a low usage threshold, and has universality.

[0012] The host computer system of the present invention can read the data information of the wireless 3D mouse in real time, communicate with the robot control system, send control instructions and record teaching points, automatically smooth the teaching trajectory, has a good teaching trajectory reproduction effect, and can adjust the dragging speed at any time, can move at high speed when fast movement is required, and move slowly when high-precision operation is required, with high integration and convenient operation.

[0013] The wireless 3D mouse used in the present invention has a flexible installation method, can be fixedly installed on the moving platform of the six-degree-of-freedom parallel robot to obtain an intuitive teaching experience, or can be detached from the robot and placed on the desktop to drag the robot remotely, with high flexibility, intuitive teaching effect, and greatly improved teaching efficiency. Description of the Drawings

[0014] Figure 1 is a schematic diagram of the hardware connection of a six-degree-of-freedom parallel robot dragging teaching system based on a 3D mouse according to the present invention;

[0015] Figure 2 is a schematic diagram of the coordinate system of the six-degree-of-freedom parallel robot and the center of the moving platform according to the present invention;

[0016] Figure 3 is a schematic diagram of the wireless 3D mouse component and its coordinate system adopted by the present invention;

[0017] Figure 4 is a block diagram of the working principle of the dragging teaching system of the present invention.

[0018] Wherein: 1. Six-degree-of-freedom parallel robot; 2. Robot control system; 3. Wireless 3D mouse; 4. Computer; 11. Static platform; 12. Moving branch chain; 13. Moving platform; 31. Programmable button 1; 32. Keycap; 33. Programmable button 2; 34. Wireless receiver Detailed implementation mode

[0019] The present invention will be elaborated in detail below in conjunction with the accompanying drawings and the implementation mode:

[0020] As Figures 1 to 3 shown, a six-degree-of-freedom parallel robot drag teaching system based on a 3D mouse includes a six-degree-of-freedom parallel robot 1, a robot control system 2, a wireless 3D mouse 3, a computer 4 and a host computer system. The wireless receiver 34 of the wireless 3D mouse 3 is connected to the computer 4, the computer 4 is connected to the robot control system 2 through a network cable, and the parallel robot control system 2 is connected to each joint motor through a cable. The wireless 3D mouse 3 collects the force and torque data applied by the operator. The host computer system in the computer 4 reads the data of the wireless 3D mouse 3, processes it into a control signal for the six-degree-of-freedom parallel robot 1 and sends it to the robot control system 2. The control system 2 converts the control signal into joint variables through kinematics and drives the motor to rotate, so as to control the moving platform 13 of the six-degree-of-freedom parallel robot to move according to the control intention applied by the operator on the wireless 3D mouse 3, realizing the dragging of the moving platform 13 of the six-degree-of-freedom parallel robot. During the dragging movement of the moving platform 13 of the six-degree-of-freedom parallel robot, the host computer system records the pose, speed and acceleration information of the moving platform 13 of the six-degree-of-freedom parallel robot at a certain frequency, and automatically generates a motion program for reproducing the teaching trajectory after analysis and processing, realizing the reproduction of the dragged teaching trajectory.

[0021] The six-degree-of-freedom parallel robot 1 is as Figure 2 shown, including three main parts: a static platform 11, a moving branch chain 12, and a moving platform 13. The coordinate system direction fixed at the center of the moving platform 13 is as shown in the figure.

[0022] The robot control system 2 can adopt a Pmac control system or other control systems.

[0023] The wireless 3D mouse 3 is as Figure 3 shown, connected to the computer 4 through the wireless receiver 34, capable of obtaining six-dimensional data through the keycap 32, including three translational data and three rotational data, and including two programmable buttons, programmable button 1 31 and programmable button 2 33, which can be used to adjust the robot dragging speed; its coordinate system direction is as shown in the figure.

[0024] As Figure 2 、Figure 3 As shown in the figure, the corresponding relationship between the coordinate system at the center of the moving platform 13 of the six-degree-of-freedom parallel robot and the coordinate system of the wireless 3D mouse 3 is as follows: the +X axis of the moving platform 13 corresponds to the +Y axis of the wireless 3D mouse 3, the +Y axis of the moving platform 13 corresponds to the +X axis of the wireless 3D mouse 3, and the +Z axis of the moving platform 13 corresponds to the -Z axis of the wireless 3D mouse 3.

[0025] As Figure 1 shown in the figure, in an embodiment of the present invention, the wireless 3D mouse 3 and the computer 4 are placed on the desktop, that is, the wireless 3D mouse 3 is separated from the six-degree-of-freedom parallel robot 1, and the robot can be dragged over a long distance. In addition, the wireless 3D mouse 3 can also be fixedly installed on the moving platform 13 of the six-degree-of-freedom parallel robot 1, so as to obtain a more direct drag teaching experience.

[0026] As Figure 4 shown in the figure, the implementation method of the drag teaching system of the present invention is as follows:

[0027] Step 1: Open the upper computer system in the computer 4, establish communication with the lower computer by clicking the button in the interaction function area. After establishing communication, start the motor power supply through the interaction function area, and click the start teaching button to start the data processing module.

[0028] Step 2: If it is necessary to reproduce the drag trajectory, the trajectory generation module can be started by clicking the record trajectory button in the interaction function area, and the pose, speed, and acceleration information of the moving platform 13 of the robot sent by the robot control system 2 in real time will be recorded by the upper computer system. If the reproduction function is not required, step 3 can be directly performed.

[0029] Step 3: After starting the data processing module, the operator can apply a drag force or torque to the wireless 3D mouse 3 according to the control intention of the six-degree-of-freedom parallel robot 1. The wireless 3D mouse 3 will detect six-dimensional data and transmit the data to the upper computer system through the wireless receiver 34. After the data processing module in the upper computer system reads the six-dimensional data, it processes it into a control signal for the robot and sends it to the robot control system 2. The robot control system 2 will control the moving platform 13 of the parallel robot to execute corresponding movements according to the control signal, realizing the operator's dragging of the moving platform 13. During the drag control process, the operator can pull the slider for controlling the robot drag speed in the upper computer interaction function area at any time to adjust the robot to drag quickly or precisely. After completing the drag teaching, if the trajectory generation module is in the on state, the operator can click the complete teaching button in the interaction function area, and the upper computer will automatically generate a trajectory reproduction file for the trajectory recorded during the dragging process; or it can be optimized, and an optimized trajectory can be generated by B-spline curve fitting and S-shaped speed planning or other methods. After the teaching is completed, close the data processing module and the trajectory generation module.

[0030] Step 4: Upload the trajectory reproduction file generated by the host computer system in the computer 4 to the robot control system 2 and run the file to complete the reproduction of the taught trajectory.

[0031] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit of the present invention and the scope protected by the claims. All of these fall within the protection scope of the present invention.

Claims

1. A teaching-by-dragging system for a six-degree-of-freedom parallel robot, characterized in that: It includes a six-degree-of-freedom parallel robot, a robot control system, a wireless 3D mouse, a computer, and a host computer system; the six-degree-of-freedom parallel robot includes a stationary platform, a moving platform, and six kinematic chains connecting the two, and each kinematic chain is driven by a joint servo motor; the robot control system communicates with the computer through the real-time Ethernet protocol, receives control instructions and drives the joint servo motors to make the moving platform move according to the operation intention; the wireless 3D mouse is connected to the computer through a wireless receiver and is used to collect the six-degree-of-freedom force and torque signals applied by the operator. The coordinate system of the wireless 3D mouse is dynamically mapped to the center coordinate system of the moving platform, and the mapping relationship is: the +X axis of the moving platform corresponds to its +Y axis, the +Y axis of the moving platform corresponds to its +X axis, and the +Z axis of the moving platform corresponds to its -Z axis; the computer and the host computer system are used to read the six-dimensional data of the wireless 3D mouse in real time to generate control instructions, record the information of the moving platform, and generate a reproduction trajectory program.

2. The drag teaching system of the six-degree-of-freedom parallel robot according to claim 1, characterized in that: The wireless 3D mouse is fixed on the moving platform of the six-degree-of-freedom parallel robot and is used to intuitively drag the robot for teaching, or detach the parallel robot from the wireless 3D mouse and place it on the desktop for remote dragging teaching.

3. The drag teaching system of the six-degree-of-freedom parallel robot according to claim 1, characterized in that: The host computer system of the computer includes an interaction function area, a data processing module, and a trajectory generation module; the interaction function area includes buttons for turning on and off the data processing module, buttons for turning on and off the trajectory generation module, a slider for adjusting the robot dragging speed at any time, and other interactions with the control system; the data processing module calls functions in the hidapi library to read the six-dimensional data of the wireless 3D mouse in real time, calibrates the data as force information, maps it to motion control instructions through an admittance model, communicates with the lower computer, and sends control instructions; the trajectory generation module is used to communicate with the lower computer, receive and record the pose, speed, and acceleration data information transmitted by the control system, and automatically generate a motion program for reproducing the teaching trajectory based on the recorded path points.

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