Pedrosa, R., MacLean, K. E. (2008). "Using Haptic Feedback to Share Control with a Smart System", in Proceedings of Poster in Graphics Interface (GI 2008), Windsor, Ontario, Canada, May 2008.
Industrial environments are often saturated with visual and audio stimuli; however, intelligent systems typically assist a user/operator to reach a control goal using visual or audio cues. We posit that haptic interfaces could be used to provide such assistance with less interference, but only if the guidance is provided in an intuitive and non-disruptive way. Using haptic feedback for guidance is not a new concept . For example, force feedback has been most used for providing continuous trajectory guidance directly to the motor control channel . Our example derives from the metaphor of a haptically rendered elastic string anchored at both ends, which represents the intelligent system’s proposed control path. The elasticity constant of the string defines the safe region around this path, which the user moves along as if pulling a bead along a slightly stretchy string. The possible divergence from the “system” path becomes increasingly limited as one moves from the center of the string towards one of the anchoring points. A more complex system-suggested control trajectory could be divided into a reasonable number (n) of serially connected string segments, with joints anchored, each with its own defined elastic behavior.