A Method for Selecting Velocity Filter Cut Off Frequency for Maximizing Impedance Width Performance in Haptic Interfaces

Abstract

This paper analyzes the effect of velocity filtering cutoff frequency on the Zwidth performance of haptic interfaces. Finite difference method (FDM) cascaded with a low pass filter is the most commonly used technique for estimating velocity from position data in haptic interfaces. So far, there is no prescribed method for obtaining the FDM + filter cutoff frequency that will maximize Zwidth performance. We present a simulation based method to demonstrate that there exists such an ideal FDM + filter cutoff frequency, and that it can be predicted by numerical simulation based on an identified model of a haptic interface. Experiments are conducted on a single degreeoffreedom (DOF) linear haptic interface to validate the simulation results.