ABSTRACT

The use of haptic interfaces makes it possible to enhance the interaction between the user and a virtual environment, by developing it on the sense of touch. Such interfaces can be seen not only in professional applications, but also in consumer applications. However, controlling these devices from a virtual environment still remains an open problem. In fact, haptic interfaces do not necessarily come with a programming library that helps controlling these interfaces in a simple manner. Some libraries available (for example GHOST by Sensable1) are specific to the devices of a given brand and to certain virtual environments. They often prove to be unsuitable for applications that use complex scenarios. Therefore, the VR application designers often have to program the haptic interfaces that they use. Similar to computer graphics that work on the synthesis of images that the user has to see (graphic rendering), computer haptics that we are going to discuss in this chapter, aim at calculating haptic sensations that the user has to feel (haptic rendering). More specifically, we will see how to calculate the set point to be sent to the control loop described in chapter 9 “Control of a Force Feedback Interface’’ of this book. We will also discuss various problems related to the simulation/device coupling.