Perception of and Response to a Haptic Device as a Function of Signal Complexity.

Haptics devices have been developed in a wide range of form factors, actuation methods, and degrees of freedom, often with the goal of communicating information. While work has investigated the maximum rate and quantity of information that can be transferred through haptics, these measures often do not inform how humans will use the devices. In this work, we measure the differences between perception and use as it relates to signal complexity. Using an inflatable soft haptic display with four independently actuated pouches, we provide navigation directions to participants. The haptic device operates in three modalities, in increasing order of signal complexity: Cardinal, Ordinal, and Continuous. We first measure participants’ accuracy in perceiving continuous signals generated by the device, showing average errors below $5 ^{o}$. Participants then used the haptic device in each operating mode to guide an object towards a target in a 2-dimensional plane. Our results indicate that human’s use of haptic signals often lags significantly behind the displayed signal and is less accurate than their static perception. Additionally signal complexity was correlated with path efficiency but inversely correlated with movement speed, showing that even simple design changes create complex tradeoffs.