Concurrent bilateral teleoperation over the Internet

This paper presents a concurrent bilateral teleoperation over the Internet, which addresses the concurrency between the local and the remote site operations. The most widely used scheme to overcome time-varying communication delay over the Internet is utilizing predictive displays, which basically insulates the operator from the communication delay by providing simulated or predictive feedback. However this loses the concurrency between the operations at the local and the remote sites. As the result, the remote site should be sufficiently intelligent to react the unexpected events immediately. In addition this, it also requires error detection and recovery routines which handle unexpected and/or malfunctioning operations, even though a human operator is supervising the operation at the remote site. To resolve this problem, the communication delay is estimated and incorporated into the predictive displays to convert the predictive to the estimative displays. The communication delay is estimated recursively using the local command, remote outputs sent back to the local site and the remote robot model.