Image map based haptic rendering of surface textures on 3-D virtual objects.

Computer haptics deals with the problem of computing the correct forces to be sent to the user through a haptic device so as to simulate a virtual object. Most haptic rendering algorithms rely only on the 3-D geometries of the virtual objects to generate the forces. Details in the surface textures increase the visual and haptic realism of objects. Therefore, the goal of this thesis is to develop a method for the haptic rendering of detailed surfaces of 3-D virtual objects. The methodology consists in the analysis of normal and height maps, and the information they provide when applied to a surface. The god-object haptic rendering algorithm was implemented and combined with image based haptic rendering techniques. The method allows the change of strength of each of the maps to control the effect of each one. Because the method is efficient and simple, image maps may be changed quickly and seamlessly and can be used in real time applications. A haptic rendering system architecture was designed and implemented in a haptic device. Tests were done in a completely virtual world with 3-D objects, to validate the method. The method was also tested in a vehicle navigation application: a live video feed from a depth sensor was implemented as a depth image and used for the haptic rendering. The real time capabilities of the method where validated and navigation tests were conducted. A tele-operated vehicle was able to avoid obstacles and navigate through a narrow passageway.