A design of adaptive H∞ control for positioning mechanism system with input nonlinearities

An adaptive H
^∞
control for positioning mechanism with input nonlinearity is proposed in this paper. It is assumed that the input nonlinearity can be described as unknown parameters term and bounded disturbance term, an adaptive H
^∞
control method is given. Proposed control strategy does not include a discontinuous function, therefore, it can avoid to cause the chattering phenomena. Moreover, in the closed-loop control system, the L
₂
gains from the disturbance to generalized outputs are made less than prescribed positive constants. The effectiveness of the proposed method is demonstrated by experimental results.