EMULATION OF MODULAR MANUFACTURING MACHINES USING CAD MODELING

Designing, testing and debugging a machine control system which contro ls mechatronic hardware elements can be a complex, time consuming and costly procedure. It is often extremely difficult for the system build er to envisage in advance the effects of small changes to the control system logic, with potentially dangerous results if the hardware consi sts of heavy machinery. It is also rare that a system builder will arr ive at a working prototype on the first attempt and discovering the re asons for incorrect operation without a suitable means of comprehendin g the problems can be an arduous task. This paper describes an approac h which supports the designing, testing and debugging of modular manuf acturing machines using 3D graphical models of the machine hardware. T he paper emphasises the underlying methodology of the approach, which involves collecting timing data from the executing control system unde r development, then emulating the operation of the machine by using th is data to drive a graphical model of the hardware. The term ''emulati on'' is used to mean modelling using data captured from the real machi ne as opposed to ''simulation'' which synthesises data. The work build s on previous research at the MSI Research Institute concerned with th e control of modular machines. Two new extensions to this work are des cribed here, which form the basis of the emulation capability. The fir st is the addition of the ability to execute the control system withou t the mechatronic hardware elements present whilst still retaining the operational behaviour of the application. The second is the mechanism for collecting the run-time data which defines these operational char acteristics, to drive the machine emulation. The features of the custo m 3D modeller are presented and its use for machine emulation is descr ibed. An example of a real control system under development is given t o illustrate the complete process. The research objectives of the work described here are concerned with the fundamental problems designers encounter when trying to prototype the control systems of modular mach ines. The research has shown that the ability to execute the control s ystem with or without the mechatronic hardware elements present can be a considerable advantage if supported by a CAD-based emulation system .