VAL: a versatile robot programming and control system

VAL is a computer based control system and programming language which has been designed specifically for use with industrial robots. In this paper, VAL is described as it is implemented as an integral part of the Unimation PUMA robot. First, the general capabilities of VAL are presented. These include the ability to interactively edit, interpret, debug, execute, and store user programs in an environment that supports concurrent console communication and program execution. Then, the system hardware is described. Next, the various methods of tool point trajectory control which are available in VAL are described. This is followed by a brief description of the VAL language. Special instructions for dynamically modifying position data are described along with instructions for automatically adapting programs based upon sensory information.