Detection of Real and Virtual Fine Surface Features With a Haptic Interface and Stylus

Abstract

Abstract In this paper we discuss the results of displaying fine surface features using a haptic interface. A stylus was connected to a haptic interface and configured so that users could explore real and virtual surfaces using the same apparatus. The surfaces consisted of sinusoidal profiles with amplitudes of 0.01–10 mm and with frequencies of 1–20 cycles over a length of 85 mm. Subjects were asked to explore the surfaces at will and count the number of waves detected. When exploring physical profiles, tests were conducted using a stylus with friction and a “frictionless” stylus with a roller. For comparison, tests were also conducted using the subjects’ fingertips instead of a stylus for physical surface exploration. Our results show that subjects’ perceptions of sinusoidal features on virtual and physical walls are qualitatively similar. At spatial frequencies of 0.24 cycles/mm and greater, the ability of humans to accurately count virtual and physical waves was also similar, despite the limited stiffness and bandwidth of the haptic interface. The results provide insight for the display of fine features such as ridges or grooves on a virtual wall.