Gravity Compensation Algorithms for Parallel Haptic Interface

This paper presents an experimental comparison of different algorithms for the gravity compensation of parallel mechanisms, with special reference to a 5DOF haptic interface that has been realized at PERCRO. Two methods for the static balancing of this mechanism have been investigated: a classical method, based on Lagrange's approach and an algorithm that adopts the screw theory. This last method allows solving the problem in a more intuitive way. Some experimental results are reported in order to confirm this approach