The role of visual haptic delay in tele-operation protocols

Abstract

In tele-operation protocols developed for robot assisted surgery one of main challenges is the introduction of force-feedback, adding the possibility of manipulating delays between haptic and visual signals. In these conditions it is relevant to understand how the human performance is influenced by visual- haptic delays. In the present research, we study the role of temporal visual-haptic delays between a haptic and a visual rendering using a haptic device in a virtual environment. In a full factorial randomized design participants were asked to judge if they first perceived the haptic or the visual rendering. The delay levels (±1250, 650, 250ms) and the stiffness values of the pliable haptic wall (83, 207, 331N/m) have been randomly presented. Log-linear analysis shows that performance is strongly affected by delay (higher is the delay better is the judgment). Moreover, an interaction between delay and stiffness have been observed. Results will discuss in light of the weighted summation model.