Track Cable-Parallel Tracking Control

Parallel Wire Driven Robot (PWDRs) is a new type of robot, which usesthe flexible cable instead of the traditional rigid rod of parallel robot as driveelements, locating and orientating its end-effector at the desired working space.It has high research values because of its simple structure, small error, strongbearing capacity, larger than the small, balanced work space, manufacturing andlower maintenance costs, so it is gradually applied to all kinds of industrial field.But from the view of the control point，parallel wire driven robots are highlynonlinear， large delay, multivariable coupling and extremely complextime-varying control systems, the traditional control methods can’t meet theirhigh quality control requirements. Therefore, there is always a big challenge toseek a good control theory and method of high reliability, robustness，andintelligence to meet the need of such complex control system of parallel wiredriven robots. The research on the control strategy in this paper has an importanttheoretical and practical significance. The main works are as follows:(1) Combining with the study of this subject LT50m parallel wire drivenrobot, the kinematics description is carried out by the method of matrix, theinverse kinematics problem is solved, and simulations on the system are madebased on the inverse kinematics analysis. Results of simulation validates theeffectiveness of the kinematics analysis.(2) Based on the summary of several dynamic analysis methods, thedynamic analysis is carried out on the LT50m parallel wire driven robot, and thedynamic model is constructed by using Lagrange’s Equations. At the same time,writing the parameterized program, then the simulation experiment is carried out,verifying the rationality of dynamics analysis. which lays a foundation for thetrajectory tracking control of robot.(3) Based on the theory of the controlling, this paper researches thetrajectory tracking control method, targeting to the features of the LT50mparallel wire driven robot. Combining their respective advantages of adaptivefuzzy control and disturbance observer, an adaptive fuzzy controller withdisturbance observer (AFCWDO) is presented to realize the trajectory tracking of the robot. This control strategy estimates and compensates the outsideinterference through the disturbance observer; At the same time, on this basis, inorder to suppress the influence of the internal uncertainty on the system, anadaptive fuzzy controller is introduced. And the MATLAB simulation showsthat the robot can effectively track the given targets with the proposed controlstrategy, meet the accuracy requirement, at the same time, the control strategyalso has a certain robustness and a capacity of resisting disturbance, which cansatisfy the practical requirement.The results of this subject provide a certain idea for cable-class robot,especially parallel wire driven robot control system, which lay a theoreticalfoundation for the research of control system，contributing a force for the wideapplication of parallel wire driven robots.