Passive exploration and static skin might be more useful than previously assumed

Which is the better of active and passive haptic exploration? This question has been hard to answer primarily because too many confounding factors have varied along with the variable of interest – presence or absence of control over movement. Similar control-related difficulties have obscured the contribution of touch and kinsthesis to haptic processes, yet these issues are important for both theoretical and practical reasons. Here we describe some experiments in which a device was used to achieve the level of control needed to determine the relative importance of touch and kinesthesis, and to compare active and passive haptic perception in two dimensions. The active passive comparison was then extended to threedimensional virtual objects. Information delivered via static skin was found to be more useful than expected, and passive exploration was sometimes better than active. However, the role of cognitive factors needs clarification.