Research On Industrial Robots Laser Cutting Application Of Trajectory Planning And System Calibration

As an advanced process technology, laser cutting is widely used in industrial fields such as automobiles, electronics, electrical equipments, aviation, metallurgy and machinofacture. It is playing a more and more important role in improving the quality of products and labor productivity and reducing finished cost and materials consumption.As high-power fiber laser of optical fiber transmission comes out and the positioning accuracy of industrial robots improves, to carry out laser cutting by using industrial robots is a hot spot for the current robot application field and laser cutting field.This paper mainly studies the application of industrial robots with laser cutting. It sets up hardware and software platforms for laser cutting, studies the key technology of off-line programming, utilizes off-line programming software to cut the workpieces whose tracks are complex via laser. The main work summary is listed as follows:1) It sets up experimental cutting platform of laser and develops robotics software with functions of System calibration, motion control and signal control via Robot Language VAL3. It also develops Industrial Personal Computer software with functions of long-range control, product management, condition monitoring and process database management via High-level Language C#.2) Conduct the analysis of descriptive approach to position and orientation of spatial coordinate system, and derive the formula of reciprocal transformation between attitude matrix and X-Y-Z Euler angle. Link parameter is adopted to derive forward kinematics solution, analysis method to derive inverse kinematics solution. Arm morphological parameter is introduced to figure out the multi-solution of inverse kinematics.Use differential transformation and calculate the Jacobian matrix.3) Study robot trajectory planning in the joint space and Cartesian space, and put forward the method of planning arc trajectory through the establishment of the coordinate system, which will simplify the interpolation algorithm. Quadratic Bezier curve is adopted to design trajectory planning at motion convergence so as to actualize robot motion process without pausing. A detecting method is brought up according to workspace overrun and singular point prone to arise from the trajectory planning in Cartesian space.The regular figures of cut-in and cut-out path are designed and it is equipped with the inscribed and outscribed function.4) Study robot system calibration. Adopt three-point method and right-handed rule to actualize the calibration of workpiece coordinate. Put forward the method of teaching four-point arm position and orientation, and actualize the calibration of tool center frame. Propose an error correction algorithm based on error in tool calibration. Write the program of calibration and correction algorithm, and the final positional error prove to be less than0.5mm through experiment.5) Use of the teach programming and off-line programming on the laser cutting experiment. Conduct workpiece modeling by means of the three-dimensional modeling software SolidWorks, and the offline programming software PEPS is adopted to get operation trajectory from workpiece. Study data formats of offline trajectory file, and realize the conversion of robots instruction by means of post processing, and finally carry out laser cutting experiment in carbon steel plate.