Utilising dynamic factory simulation to improve unit cost estimation and aid design decisions

Utilising dynamic simulation methods to estimate manufacturing resources, can improve unit cost estimation and aid design decisions. This paper introduces a framework specification that combines Computer Aided Design (CAD), Computer Aided Process Planning (CAPP) and Discrete Event Simulation (DES) technologies. The framework is used to aid a design team in understanding the consequences of design decisions in terms of cost and manufacturing resources, by returning unit cost and manufacturing based results, directly to the design team, within the design environment. Dynamic Resource Estimation System (DRES) is a system being developed to implement the framework and is presented in this paper.

A Product Development Process (PDP) represent the life cycle of a product from conception of the initial idea, through design, manufacture, operation and finally disposal. A PDP typically contains a number of stages that can be classified into categories. The Rolls-Royce PDP (Rolls-Royce Plc, 2005), illustrated in Figure 1, contains seven stages and three categories. This paper will focus specifically on stage 1, developing the preliminary design of a product that fulfils a business opportunity.

Rolls-Royce product development process

The preliminary system incorporates five tools: a CAD tool (Unigraphics NX (UGS NX)), a GUI written in C#, a database (Microsoft Access), a simulation tool (Anylogic) and a static cost modelling tool (Vanguard studio). Figure 4 shows which tools are used by each framework section.  

DRES sections and associated tools

This paper presents a framework specification that combines CAD, CAPP, CAM technologies with a knowledge database, to provide data for conducting manufacturing simulations and improve cost estimation. By combining these technologies with a knowledge database and a GUI, feedback of unit cost estimation and manufacturing resources can be given directly to a design team within their design environment. This feedback should aid a design team to understand the consequences of design decisions in terms of cost and manufacturing resources.