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 plan ning of plastic injection mould bases. The computer-aided process-planning system, developed for IMOLD(R) will extract and identify the operations req uired for machining. These operations are considered together with their pr ecedence constraints and the available machines before the process plan for the mould base plate is generated. The process plan is optimised by a bran ch and bound based algorithm. Overall machining time has been proposed as t he objective function for optimisation. The ability of this algorithm to se arch intelligently for a feasible optimised solution is illustrated by an i ndustrial case study. A brief comparison with a genetic algorithm based pro cess planning system is also made. The result of this development will allo w users to optimise process plans easily for any given mould base, with opt ions to suit dynamic changes on the manufacturing shop floor.