The main contribution of this paper is to examine, via experimental investigations of a
Type 2 servomechanism, the engineering feasibility of a sliding mode based control design,
in which a discontinuous estimator is used in feedback compensation of uncertainties and
exogenous disturbances. Experimental results of a transputer controlled single-degree-of-
freedom motion control system are presented. The experimental system consists of a
conventional DC servo gear motor with encoder feedback and variable inertia load coupled
by a relatively rigid shaft