Abstract
Adding physicality to virtual environments is considered a prerequisite to achieve natural interaction behavior. While physical properties and laws can be built into virtual environments by means of physical engines, providing haptic feedback to the user requires appropriately designed and controlled haptic devices, as well as sophisticated haptic rendering algorithms. While in the past a variety of haptic rendering algorithms for the simulation of human-object interactions were developed, haptic interactions with a virtual character are still underinvestigated. Such kind of interactions, however, pose a number of new challenges compared to the rendering of human-object interactions as the human expects to interact with a character that shows human-like behavior, i.e., it should be able to estimate human intentions, to communicate intentions, and to adapt its behavior to its partner. On this account, algorithms for intention recognition, interactive path planning, control, and adaptation are required when implementing such interactive characters. In this chapter two different approaches for the design of interactive behavior are reviewed, an engineering-driven and a human-centred approach. Following the latter approach virtual haptic interaction partners are realized following the workflow record-replay-recreate. To demonstrate the validity of this approach it is applied to two prototypical application scenarios, handshaking and dancing.