Abstract :
Describes the design and implementation of a hierarchical control system for flexible assembly cells. The system is innovative for two reasons: it is implemented using object-oriented programming (OOP) techniques and it uses a product-centred control strategy. conventional robot control systems are either equipment oriented, where programs are sequences of commands to robots and grippers, or task based, in which the program represents a sequence of parameterised processes. The focus of attention is the product being assembled. it is argued that this leads to a simpler, more flexible and more intelligent control system. Finally, a prototype system implemented in KEF, an AI toolkit, on a symbolics Lisp machine is described