Haptic Technology
1.1 What is *Haptics*? Haptics refers to sensing and manipulation through touch. The word comes from the Greek ‘haptesthai’, meaning ‘to touch’. The history of the haptic interface dates back to the 1950s, when a master-slave system was proposed by Goertz (1952). Haptic interfaces were established out of the field of tele- operation, which was then employed in the remote manipulation of radioactive materials. The ultimate goal of the tele-operation system was "transparency". That is, an user interacting with the master device in a master-slave pair should not be able to distinguish between using the master controller and manipulating the actual tool itself. Early haptic interface systems were therefore developed purely for telerobotic applications. {draw:frame} {draw:frame} Fig.2.1Basic architecture for a virtual reality application incorporating visual, auditory, and haptic feedback. • Simulation engine: • Visual, auditory, and haptic rendering algorithms: Compute the virtual environment’s graphic, sound, and force responses toward the user. • Transducers: Convert visual, audio, and force signals from the computer into a form the operator can perceive. The human operator typically holds or wears the haptic interface device and perceives audiovisual feedback from audio (computer speakers, headphones, and so on) and visual displays (a computer screen or head-mounted display, for example). 2.2 System architecture for *haptic* rendering: {draw:rect} {draw:rect} {draw:rect} {draw:frame} {draw:frame} Fig 2.2Haptic rendering divided into main three blocks *S- contacts* occurring between an avatar at position X and objects in the virtual environment. Fd- *return* the ideal interaction force between avatar and virtual objects. Fr- Force to the user 1.Collision-detection algorithms detect collisions between objects and avatars in the virtual environment and yield information about where, when, and ideally
References: http://www.sensable.com/products/datafiles/phantom_ghost/Salisbury_Haptics95.pdf http://www.wam.umd.edu/~prmartin/3degrees/HAPTIC%20TECHNOLOGY1.doc http://www.sensable.com http://www.logitech.com http://www.technologyreview.com