Accurate multi-DOF kinesthetic haptic display using instantaneous restriction space

This paper proposes an accurate kinesthetic haptic display method for a multi-DOF haptic interface. Position-position (p-p) architecture plays an important role in a haptic interface like four channel architecture since force reflection using only force sensor information induces a serious problem if a slave manipulator is constrained by unexpected obstacles the force sensor cannot detect. However, the conventional p-p architecture in literature has limitations to apply to a multi-DOF haptic interface. This paper indicates the limitation through an example and proposes a novel haptic display method using instantaneous restriction space (IRS). IRS can be calculated using Jacobian and joint angle error of a slave manipulator. Since the proposed method has the form of impedance two port architecture in the sense of data flow, it can be easily combined with the previous results of two-port haptic display framework in literature. The method is compared to the conventional p-p architecture through experiments.