End-trajectory Planning And Tracking Control Of Robotic Arm On Scissor Platform

China is currently the world ’ s most highways,tunnels,culverts and other countries.In recent years,China ’ s highways and tunnels are developing from large-scale construction period to operation and management period.At present,the disassembly,maintenance and cleaning tasks of tunnel lighting lamps and lanterns are mostly used scaffolding or overhead vehicles and manual operation devices to complete the maintenance,cleaning and replacement of lamps and lanterns.The maintenance efficiency is low,and there are hidden dangers in the manual operation process.The maintenance process is long,resulting in longterm traffic congestion.The installation of mechanical arm on the scissors platform instead of manual operation can effectively solve the above problems.Therefore,the trajectory planning and control analysis of the mechanical arm on the scissors mechanism should be put on the agenda.In this paper,the manipulator on the scissors platform is taken as the research object,and the trajectory planning and control on the flexible platform are of great significance for carrying the manipulator on the flexible body.Due to the flexibility of the scissor platform,the establishment of the dynamic model of the manipulator on the scissor platform becomes complex,and the trajectory planning and control analysis of the manipulator will also be affected.In this paper,the manipulator on the scissor platform is taken as the research object,and the following research is carried out from the model simplification,dynamic modeling,trajectory planning and vibration control analysis :(1)The dynamic model of the manipulator on the scissor platform is studied.The model of the manipulator on the scissor platform is simplified.The dynamic model of the manipulator on the scissor platform is established by using the Lagrange principle,and the dynamic equation of the manipulator on the scissor platform is derived.The model is established on MATLAB /Simulink,and the established manipulator model on the scissor platform is verified by the input torque method.(2)The trajectory planning of the manipulator end-effector on the scissor platform is studied.The cubic and quintic polynomial interpolation methods in the trajectory planning,the plane linear arc interpolation and the spatial plane arc interpolation methods in the Cartesian coordinate system are introduced.The cubic polynomial interpolation and quintic polynomial interpolation formulas are derived.The manipulator joints on the scissor platform are planned,and the angle,angular velocity and angular acceleration curves of the manipulator joints on the scissor platform are analyzed.(3)Aiming at the control problem of the manipulator on the scissor platform,based on the original sliding mode control strategy,a new exponential reaching law is designed to improve the tracking speed of the end trajectory of the manipulator.The RBF neural network adaptive control is used to approximate the uncertainty of the manipulator on the scissor platform,and the stability of the manipulator control system on the scissor platform is proved.The simulation results by MATLAB / Simulink show that the control strategy can effectively reduce the trajectory tracking error of the manipulator end on the scissor platform,and significantly accelerate the tracking response speed of the manipulator end actuator on the scissor platform,and effectively reduce the chattering.(4)Aiming at the problems of slow tracking speed and low accuracy of the end trajectory of the manipulator on the scissor platform,the dynamic equation of the joint angle of the manipulator is transformed into the dynamic equation of the end point of the manipulator.On this basis,an improved sliding surface is designed.In order to reduce the chattering of the system,the super helix algorithm is used to design the control law.The modeling uncertainty of the manipulator on the scissor platform is approximated,and the stability of the manipulator control system on the scissor platform is proved.The simulation results show that the control strategy can effectively improve the convergence speed of the manipulator end trajectory on the scissor platform,and effectively reduce the chattering.The research contents of this paper can provide some theoretical basis and technical support for the dynamic modeling,trajectory planning and tracking control of the manipulator on flexible body,and provide very important practical significance for the expansion of the manipulator.