Patent ID: 7420539

Claim:
A method of stabilizing a haptic interface of a haptic system in which an interaction between a control system including a virtual environment and a haptic device is supported, the method comprising: detecting a value of a physical parameter related to a motion generated by a human operator's action in an actual element included in the haptic device at each predetermined time interval; calculating a force to respond to the human operator reversely through the haptic device in the virtual environment in response to the value of the physical parameter; calculating a bounding parameter that satisfies first stabilization conditions in which energy generated during sampling and holding is to be dissipated by the haptic device and second stabilization conditions in which energy generated by the control system is to be passive, from the calculated force and the calculated value of the physical parameter; if the calculated bounding parameter is out of a predetermined bounding range, adjusting the calculated bounding parameter in the predetermined bounding range; adjusting a force to be applied to the actual element included in the haptic device using the adjusted bounding parameter; applying the adjusted force to the actual element included in the haptic device; and repeatedly performing the detecting of the value of the physical parameter through the applying of the adjusted force at each predetermined time interval, wherein the bounding parameter β(k) is calculated by β ⁡ ( k ) = F e ⁡ ( k ) - F d ⁡ ( k - 1 ) v d , k ⁢ ⁢ or ⁢ ⁢ β ⁡ ( k ) = T ⁢ F e ⁡ ( k ) - F d ⁡ ( k - 1 ) x d , k - x d , k - 1 , where T is the predetermined time interval, F e (k) is a force to respond to the human operator in the virtual environment in response to the physical parameter detected at a k-th time interval, F d (k-1) is a force applied to an actual element of the haptic device 41 at a (k-1)-th time interval, and V d,k and X d,k is velocity or position detected by the haptic device by human operator's manipulation.