Adaptive Control for the Four-Bar Linkage Mechanism Based on Differential Evolution

Position tracking in the four-bar linkage mechanism is an important task in several high precision automation processes in the industry. Accuracy may decrease due to uncertainties, but an adaptive control approach can handle them. In this work, an adaptive control strategy for the trajectory tracking of the four-bar linkage mechanism is presented. This strategy includes an adaptive mechanism based on a dynamic optimization process. In this process, a dynamic optimization problem is stated and solved on-line using a meta-heuristic optimizer to find the best set of control parameters which are used in a PID-computed-torque controller. Differential Evolution is chosen as the optimizer and a variant with an optimum tracking mechanism which allows to maintain the diversity of solutions is proposed in order to handle the changing best solution of the dynamic optimization problem. A full statistical analysis is used to prove the effectiveness of the proposed strategy.