Identification of Joint Stiffness with Bandpass Filtering

This paper proposes a method to identify the joint sti ness of a robot using a bandpass lter. It is based on moving one axis at a time. The dynamic model reduces to a model which is linear in relation to a minimum set of dynamical parameters which have to be identi ed. These parameters are estimated using the least squares solution of an over determined linear system obtained from the sampling of the dynamic model along a closed loop tracking trajectory. Conditions for a good data processing before identi cation are exhibited through practical aspects concerning data sampling and data ltering. An experimental study shows the efciency of the method with two sets of data depending on motor and joint position measurements.