Research And Application Of Control Method For Medical Flexible Manipulator Based On Active Vibration Suppression

The medical flexible mechanical arm is an important part of the heavy ion cancer treatment device.Its main role is to complete the operations of patient support,positioning and treatment.In this paper,the medical flexible manipulator independently designed by the research group is taken as the research object.For the problem of the elastic vibration generated by the end of the manipulator during the positioning of the arm due to the flexibility of the arm Shaping is used as feed-forward control,and fuzzy PID is used as the active vibration suppression control algorithm of feedback control.A fuzzy PID controller based on optimal input shaping is established to achieve smooth motion and accurate positioning during the positioning process.Joint simulation and practical application verify the rationality and effectiveness of the designed active vibration suppression controller.The main research contents and results of this article are as follows:(1)According to the structural characteristics of the small arm of the medical flexible mechanical arm,it is simplified to Euler-Bernoulli beam,its deformation is described by the hypothetical modal method,and the Lagrangian method is used for dynamic analysis to derive the state space The equation lays the foundation for the design of active vibration suppression controller and joint simulation.At the same time,the natural frequency of the finite element modal analysis and numerical calculation are compared to verify the correctness of the deformation description.(2)Analyze the advantages and disadvantages of PID control and fuzzy control,combine the two control methods,and take into account the slow system response and the impact of residual vibration,combined with the optimal control theory,put forward the optimal input shaping control strategy,and in MATLAB / Simulink builds the corresponding control module,and then designs a fuzzy PID controller based on optimal input shaping.(3)Establish a three-dimensional model of the medical flexible manipulator arm through ADAMS,and perform joint simulation with the control model built by Simulink.Firstly,Simulink is used for numerical simulation,and the control effects of the three controllers on angular displacement tracking,terminal vibration speed and vibration displacement are analyzed,and the control effects are compared to verify the effectiveness of the optimal input shaping fuzzy PID controller.Finally,the results of joint simulation and numerical simulation are compared to further verify the correctness of the combined control.(4)Build an experimental platform for medical flexible arms,import the control module built by MATLAB / Simulink into TwinCAT3 of Beckhoff,write the corresponding motioncontrol program,and control the mechanical arm for rotary movement through configuration and configuration.Test the vibration speed and vibration displacement of the end of the manipulator under uncontrolled and three kinds of controllers,compare their vibration suppression effects,and verify the effectiveness of the designed controller in engineering practice.In this thesis,by studying the active vibration suppression control method of medical flexible manipulator,a fuzzy PID controller based on optimal input shaping is designed to provide effective guarantee for the precise positioning of the manipulator and rapid radiotherapy.At the same time,the research in this paper also has important theoretical value and engineering application value in other fields.