Partially decentralized sliding mode control of two flexible-link robots to reduce transient responses

The use of slender and light flexible structures has increased in many applications, due to the requirement of more efficient structures. One objective of this work is to generate approximated models of two flexible-link robots for control purposes, which include rotational actuators, piezoelectric actuators, and different kinds of sensors (acceleration and deformation). The models are obtained under a classical mechanics approach: Lagrange Euler energy balance. Some parts of the resulting model involving integral terms are calculated using symbolic programming software, whereas other parts are implemented and calculated dynamically during simulation. One model is for one flexible-link robot and the second model for a two flexible-link robot. The latter is a simplification for the controller calculation. The resulting models are simulated in Matlab/Simulink. The second objective is to develop a Lyapunov based controller for joint tracking and active vibration suppression with sliding mode add-on for the one flexible-link case, then an extension is performed for the two flexible-link case. The required parameter values for the implementation of the controllers are obtained from the simulation of the formulated models. Experimental results show the effectiveness of the proposed controllers.