Preliminary two dimensional haptic thresholds and task performance enhancements

Abstract

Many tasks may be performed with greater efficiency and speed with haptic assistance. Using the Penbased Haptic Display, a low-power, low-friction, and high-precision device, we performed two separate experiments to measure two properties of human/haptic interactions. In the first experiment, we measured the level of force at which a subject may detect the presence of haptic feedback at a 71% accuracy level using a converging adaptive threshold algorithm. The average haptic threshold of eleven subjects was 20.8 milliNewtons. The second experiment quantifies changes in task performance using Fitts' Law. We measured improvements at three force levels compared to no force.