Performance analysis of a soft tip robotic finger controlled by a parallel force/position regulator under kinematic uncertainties

The performance of a modified parallel control scheme is examined under surface kinematic uncertainties using nonlinear stability analysis. The controlled system is a robotic finger with a soft hemispherical fingertip of significant radius in contact with an unknown surface. Analysis of the control system performance shows that force converges to the desired value, whereas position errors stay close to zero and in some cases can even vanish despite uncertainties. Simulation results support the theoretical findings and illustrate the performance of the proposed controller.