Adaptive output feedback control of uncertain gear transmission system with dead zone nonlinearity

In this paper, a backstepping based adaptive output feedback control scheme is presented for a gear transmission servo system with an uncertain sandwiched dead-zone nonlinearity and uncertain motor parameters. To handle the issue that only the angular position of driven gear is measurable, state estimation filters are designed. By introducing a nonlinear damping term in the virtual control design of each recursive step and adding robust terms in the parameter update laws, the effects due to dead-zone nonlinearity are effectively compensated. It is shown that all the closed-loop signals are ensured bounded and the output regulation error converges to a compact set. Simulation results are provided to show the effectiveness of the proposed adaptive control scheme.