Adaptive robust constraint-following control for mechanical systems with leakage and dead-zone

The paper proposes an adaptive robust control to let mechanical systems to approximately follow the designed constraint with uncertainty. The uncertainty considered in the system is time-varying and bounded. It is bounded, but the exact bound is unknown. A novel leakage and dead-zone type adaptive law is constructed, which emulates a parameter vector relevant to the uncertainty bound. With the adaptive parameter, the robust control can guarantee the system performance as uniform boundedness and uniform ultimate boundedness regardless of the uncertainty through the theoretically and the illustration of an example.