A fuzzy PD-like scheme for two underactuated planar mechanisms

In this paper, a two-rule-based fuzzy PD-like scheme is applied to swinging-up and then stabilize mechanisms at unstable open-loop equilibrium states. The mechanisms considered are the so-called pole-cart system and the Pendubot. In both cases the fuzzy PD-like scheme is derived from non-complete sets of linguistic rules that links some mechanism states to the sign of a single control action. A simplified Tsukamoto's reasoning method and quasi-linear-mean aggregating operators are used to derive and analyze the controller input-output mappings. Simulations (pole-cart) and hardware experiments (Pendubot) illustrate the applicability of the proposed scheme. The new fuzzy PD-like scheme design and its applications are the main contribution of the paper.