Handle apparatus for a power-assist device

Abstract

A handle apparatus is for use with a device which has a movable component and a variable speed motor system which is responsive to an error signal for driving the movable component to desired positions corresponding to the error signal. The handle apparatus includes a central stationary support member which can be mounted to the movable component. The support member is adapted to receive a miniature force sensor which includes a linear variable differential transformer having an operative axis. The member receives one force sensor for each axis in which power-assist is desired; with the axis of each force sensor positioned corresponding to each axis of power-assist. Each force sensor is electrically connected to an input signal and has an actuator translatable along the operative axis connected to a central core and has a base containing the transformer wherein movement of the actuator translates the core within the transformer to produce the error signal corresponding to the magnitude and direction of the translation of the core. A generally hollow, cylindrical sleeve encloses the support member and the force sensors to form a manually engageable surface. The sleeve is adapted to independently engage each actuator of the force sensors. Each actuator of the force sensors operates through a spring diaphragm which positions and returns the sleeve to a stable position and provides elastic resistance to force in any direction. Any manual force applied to the sleeve translates the corresponding actuator to thus produce the error signal which is proportional to the magnitude and direction of the force.