The PHI system is a master-slave type haptic interface with two major components: 1) the master arm, 2) computer-generated slave manipulator and the remote environment. The system provides force-reflecting interaction between the human arm and a computer-generated world. It accepts the motion of the human arm with minimal resistance, communicates it to the virtual environment, and applies the virtual interaction forces to the arm of the human operator. The sensory feedback is implemented in the form of joint moments that result from a force vector at a "Hot Spot" located at the middle finger knuckle of the virtual hand. Specifically, the human operator feels the interaction only when the "Hot Spot" of the slave manipulator comes to a contact with an external virtual object.

 Punching a ball      Yoyo        Tablet drawing  Video (830Kb, MPEG)