A Study on the Formulation of CAD Data Exchange System Using STEP.

An implementation method of STEP data exchange system is proposed based on a program generation method.Firstly, a formal specification of the data exchange process is derived from examining the data integrity during the data conversion.Using EXPRESS, the specification can be described in the form of a STEP application protocol, CAD data schema definition and data conversion functions, which is then translated to generate most of the system.In the system, STEP data input and output programs are prepared as generic.Only CAD data input and output programs are CAD system dependent and prepared separately.The data to be exchanged are input into data repository, then data integrity checking is performed.Data conversion is done for the data in the data repository and stored again after the data integrity checking after the conversion.The proposed method is an exact implementation of STEP standard and provides a system with high portability and flexibility.