| As a process of changing physical materials via gathering of high-energy light spots,laser cutting is a non-stress means of processing that has found application in multiple fields.Particularly in the field of aerospace crafts,precision instruments,and biomedical engineering,laser cutting has been playing an indispensable role.The traditional laser cutting is expected to maintain the overlapping between the high-pressure draft and the laser beam axis so as to realize cutting of materials.Research has suggested that to separate the high pressure draft direction from the laser beam axis can effectively improve the quality and efficiency of laser cutting.In this thesis,a high-precision,high-durability,low-friction five degree of freedom maglev laser light path controller is proposed as the execution mechanism of laser cutting.The PID control and the active-disturbance-rejection control are used to control the maglev laser light path controller,then drive the multiple degree of freedom orienteering,thus improving the laser cutting quality and efficiency.In order to realize the compact structure and quick response of the magnetic levitation laser light path controller,an active magnetic levitation bearing structure is adopted and a differential electromagnet is used to drive it.Additionally,electromagnet parameters that can ensure stable suspense and multiple degree of freedom maglev platform are given by the single unit electromagnet so as to improve the control precision of the maglev platform motion position.The maglev platform motion control is realized of the maglev laser light path controller.The Lagrangian equation is used to establish the maglev platform dynamic model.Meanwhile,the state-space equation is built to verify the system controllability and observability.According to the maglev platform dynamic model,the five degree of freedom maglev laser light path control system is established for the maglev platform multiple degree of freedom motion control.Translation and overturn control of the maglev platform based on the conventional PID control are conducted to verify that the maglev laser light path controller can realize rapid response and multiple degree of freedom driving of the maglev platform.Because of special note that the output displacement of the maglev platform under the PID control will be faced with significant overshoot when system settings are changed.Therefore,the integral separation PID control is proposed,which sets the integral action to act according to the variation range of the system error.After parameters are adjusted,simulation analysis is conducted on tracking performance and anti-jamming performance of the maglev platform under MATLAB/Simulink.The displacement output results of the suspension platform in all directions prove that the integral separation PID is better than the conventional PID in suppressing the overshoot.Aiming at the deficiencies of the PID controller in the system dynamic response characteristics and anti-interference performance,the expansion status observer is introduced for online estimation of the system output and status variables as well as system disturbances.Besides,combining the error compensation link,the second-order LADRC controller is designed.In order to verify the superiority of the second-order LADRC controller,the pole configuration method is used to tune the parameters and the characteristics of the LADRC controller are analyzed,MATLAB/Simulink is used for a simulation analysis.At the same time,the tracking performance and dynamic characteristics of the suspension platform motion control are experimentally analyzed.According to the simulation and the experimental results,the second-order LADRC is superior to the PID control in the overshoot and response speed of the magnetic levitation laser light path controller to drive the motion of the magnetic levitation platform. |
