CONTROL SCHEMES FOR STABILIZATION OF COMMUNICATION DELAY FORCE-REFLECTING TELEOPERATORS WITH

We present a general approach to stabilization of bilaterally controlled teleoperators in presence of delay in the communication channel. A standard teleoperatdon system consists of two manipulators called master and slave, and a communication chanel between them. The master is moved by.the human operator, and the information about master's trajectory is sent through the communication chanel to the remotely located slave. The slave is controlled to follow the motion of the master. In force-reflecting (or bilateral) teleoperator systems, a contact force due to the environment is measured on the slave side and sent back to the motors of the master. In the presence of time delay an the communication channel such a force feedback makes a telerobotic system unstable. The general idea of OUT approach is to make both the master and the slave manipulators input-to-state stable, so that stability of the overall telerobotic system can be guaranteed for any communication delay by using an appropriate version of the ISS small gain theorem. We discuss several versions of the stabilization algorithm pmposed, in particular, an adaptive version as well as a version which does not utilize velocity measurements.