Nonlinear Compensation of a Second-and Third-Order System with Dry Friction

Systems having dry friction nonlinearity can be stabilized by introducing intentional nonlinear passive compesation. For small ramp inputs it is necessary to increase the damping by a derivative control which becomes saturated for high ramp rates. To decrease the steady-state error at high ramp rates and achieve stability, a dead zone before the integrator is used. A scheme for an input adaptive system is also presented in this paper.