As automatic manufacturing systems become more sophisticated, there is an increasing need for advanced robots which can be easily integrated into the overall system. These robots need to interact with both a supervisory control network and with various sensory devices. VAL-II is a new robot control system and programming language which addresses these needs by supporting network communications, general sensory interfaces, real-time trajectory modification, and concurrent user-program execution. In addition, VAL-II includes high-level computer programming facilities that allow professional programmers to develop special-purpose application programs which simplify the operator interface.

This paper describes an approach to programming and controlling robot manipulators which facilitates the use of sensory information. Robot actions are specified by declaring software servo processes which control the robot's various degrees of freedom. These servo processes can involve position, orientation, force, and torque information from the robot itself, or data from external sensors. Robot tasks are programmed by dynamically modifying the servo processes or by changing set points to these processes. Condition monitors, which have access to program and sensory information, detect the completion of program steps.