Passivity analysis of a 1-DOF haptic system with consideration of human arm impedance

A new passivity condition for designing a 1-DOF haptic system is derived with consideration of human arm impedance. The method includes a human arm impedance model of a newly defined ideal mass-spring system. The developed passivity condition guarantees that the virtual wall requires more work than the ideal mass-spring system to compress. The condition guarantees that extractable energy from the virtual wall is less than the ideal system during the release phase. Eventually, the total energy of the haptic system is guaranteed to be less than or equal to that of an ideal mass-spring system whose passivity is guaranteed for all the possible user movements. The developed condition is also shown to be necessary and sufficient for the passivity of the haptic system.