ONR Annual Review 1997. Tactile Sensing and Information Processing for Man andMachine Systems

摘要

Haptic interfaces, that apply forces to the fingertips of a human operator, canbe classified as grounded or ungrounded. Grounded devices, such as SensAble Devices' Phantom or Immersion's Impulse Engine, are attached to a stationary object such as a desk. When the operator touches a virtual wall, a contact force is applied through the interface, inhibiting further motion. For ungrounded devices, a contact force is felt but there is no impediment to motion of the arm. Experiments were conducted at Stanford to compare how accurately subjects could identify contacts with virtual walls using ungrounded versus grounded feedback. Two haptic interfaces were constructed and operated in three modes: with grounded force feedback applied to the wrist, with ungrounded forces applied to the fingertips, and with grounded wrist forces in addition to fingertip forces. Tests were conducted to see how quickly subjects could arrest motion upon sensing contact (measured as virtual boundary penetration) and how accurately they could distinguish among objects of different size.