Force reflecting haptic interface

摘要

A connection element such as a thimble connects to a user's body member and, through a linkage, to a ground reference. The apparatus physically exchanges a force with a user in an environment local to the user. The linkage powers at least three independent freedoms of the connection element relative to the reference. It also maintains at least one independent freedom of the connection element relative to the reference free of power. Up to three independent freedoms of the connection element may be maintained free of power, and up to five independent freedoms may be powered. A gimbal connects the gimbal to the linkage. Zero, one or two of the gimbal axes may be powered. A five bar linkage connects the connection element to a counter-balance that also includes two actuators. A third actuator connects the five bar linkage to the reference. The two actuators of the counterbalance may be connected to the next link in the chain to the reference through a single cable. Signal processing equipment powers the actuators to deliver a signal at the connection element that represents a virtual situation generated by a programmed computer, or physical conditions in a remote environment. A virtual switch presents to the user the force and displacement relationship of a spring switch. A virtual bristled brush presents the force and displacement relationship of such a brush, while also changing the virtual environment to reflect the user's changes in location.