InTouch consists of a pair of synchronized distributed rollers that each consists of three cylindrical rollers mounted on a base. Two people can roll their hands over the devices which afford unbounded rotary motion between two people who can twist the rollers back and forth. As a consequence, there is a force feedback circuit. When one of the rollers is rotated, the corresponding roller on the remote object rotates in the same way. This behavior can be achieved using haptic (force-feedback) technology with sensors to monitor the physical states of the rollers and internal motors to synchronize these states.
Source: Brave, S. and Dahley, A. 1997. inTouch. In Extended Abstracts on Human Factors in Computing Systems Looking to the Future (CHI’97). ACM Press, 363–364.
Brave, S., Ishii, H., Dahley, A. 1998. Tangible Interfaces for Remote Collaboration and Communication. In Proceedings of CSCW '98
http://tangible.media.mit.edu/project/intouch/
