A branch and bound algorithm based process-planning system for plastic injection mould bases

This paper describes the use of artificial intelligence in the process planning of plastic injection mould bases. The computer-aided process-planning system, developed for IMOLD(R) will extract and identify the operations required for machining. These operations are considered together with their precedence constraints and the available machines before the process plan for the mould base plate is generated. The process plan is optimised by a branch and bound based algorithm. Overall machining time has been proposed as the objective function for optimisation. The ability of this algorithm to search intelligently for a feasible optimised solution is illustrated by an industrial case study. A brief comparison with a genetic algorithm based process planning system is also made. The result of this development will allow users to optimise process plans easily for any given mould base, with options to suit dynamic changes on the manufacturing shop floor.