The application of multi-agent systems for STEP-NC computer aided process planning of prismatic components

Abstract

For many years, manufacturing firms have been seeking more efficient ways of manufacturing components with CNC machines. The emerging standards ISO 14649 and ISO 10303 (AP238) present an opportunity to revolutionize the way CNC machines are traditionally programmed. These standards better known as STEP-NC replace the traditional tool movement description languages with hierarchical data structures that allow a new breed of CNC to store part geometry together with the working steps of the operations required to manufacture the part. STEP-NC provides the ability to store and utilise high level and detailed information from the CAD system to the intelligent STEP compliant CNC controller. With the advent of STEP-NC, computer aided process planning has become a critical link in the CAx process chain with the major requirement to generate interoperable process plans. The authors therefore believe it is necessary to redefine CAPP to reflect the change from the traditional tool movement based programming to STEP-NC based programming. This paper examines the application of distributed artificial intelligence methods, namely collaborative multi-agent systems in designing an object-oriented process planning system for prismatic components in a STEP-NC compliant environment. The specification and design of a prototype system entitled the Multi-Agent System for Computer Aided Process Planning (MASCAPP) is outlined. Two test components have been designed, process planned, simulated on the machine controller and finally machined, to demonstrate the capabilities of the system and illustrate the activities required to implement STEP compliant manufacturing.