Tracking Control Of PUMA 560 Under Random Disturbance

PUMA 560 is widely used because of its human-like arm.For the PUMA 560 in random working environment,the tracking control problem is considered in this thesis.Firstly,an appropriate stochastic model of PUMA 560 is established.Then,based on the established model,two kinds of controllers are designed for different situations to achieve the desired performance of the closed-loop system.Finally,a real physical component model of PUMA 560 is built based on Simscape,and the simulation results showed the effectiveness of control strategies.The main work is as follows:(1)Random modelingThe 6 degrees of freedom of the system and the existence of random noise increase the difficulty of modeling.Firstly,the random noise is not considered and with the aid of the coordinate frames established by D-H method,the deterministic model is established by the Lagrangian mechanics.Then,according to the dynamic and static method and the principle of relative motion,the influence of random noise is transformed into the system along the links of the manipulator,which is regarded as the disturbance to the torque.Thus,the stochastic model of PUMA 560 is obtained.(2)Random adaptive controlWhen the mass of the grabbed object is uncertain,the unknown parameters are separated from the coupling items by the parameter separation method.By using adaptive law to estimate unknown parameters and noise separation technology to deal with random noise,a random adaptive controller is designed such that the closed-loop system is noise-to-state practically stable in probability,and the tracking error can be made sufficiently small by adjusting parameters.(3)Random switch controlIn order to achieve better grasp,the desired grasp trajectory is designed through path planning.The sudden change of quality and the existence of random noise in the process of grasp increase the difficulty of grasp control.Based on the established model,by using common Lyapunov function and noise separation technology,a random switching controller is designed to make the PUMA 560 grab the object along the desired trajectory as far as possible,while ensuring that all the signals of the closed-loop system are bounded in probability.