Hierarchical fuzzy logic control of a manipulator with slewing and deployable links

The advantages of combining a conventional controller and a knowledge-based approach are addressed in the specific context of regulating a robotic manipulator with deployable and slewing links. A hierarchical structure having a high-speed crisp-algorithmic controller at the bottom layer and an intelligent tuner at an upper layer is developed. The top-level intelligent tuner uses a valid set of linguistic rules for adjusting proportional-integral-derivative servos, based on the theory of fuzzy logic. The behavior of the system is evaluated on the basis of the numerical simulation results as well as experiments with a prototype manipulator system. Results suggest significant improvement in the system performance through the fuzzy logic-based hierarchical control structure.