Synchronization and control of supermedia transmission via the Internet

The growth of the Internet has been accompanied by an increase in its application. Many new Internet based applications have been introduced during the past decade. One of the most interesting of these is teleoperation, where the Internet is used as a bridge between operators and machines. The operator sends commands and receives visual and haptic feedback. Collectively, we refer to all those streams as supermedia. Teleoperation over the Internet comes with several problems: delay, lost packets and disconnection. All of these limitations may cause instability and desynchronization in teleoperation systems especially if those systems include haptic feedback. Most of the previous work in Internet based teleoperation rests on many limiting assumptions: for example, time delay is constant or has an upper bound, control is not in real-time. This paper presents a new real-time haptic feedback system that deals with these limitations and difficulties without any assumptions made regarding the time delay. The approach is based on event based control, which has been implemented on a mobile robot and a mobile manipulator over the Internet.