Research On A Component Based Approach To Virtual Instrument Software Development

With special design of hardware and software, Virtual Instrument (VI) could make full use of existing computer resource and realize all the function of ordinary instrument, as well as some of function that ordinary instrument can not realize. The thinking of "The software is the instrument" achieves a great breakthrough for the concept of the traditional instrument, the VI has been widely applied in test, measurement, automation and other fields. But Virtual Instrument Software (VIS) design greater dependence on hardware structure and tested target, the minor differences of latter will affect software structure and process, and make it difficult to software reuse.In order to solve the problem of software reuse, this paper presents a component based approach of VIS development, and basically realized the process reuse and design reuse.This paper first introduces the development process and research status, VIS's software architecture, component model and assembly methods of VI. VIS is divided into four relatively independent software architecture, which are UI level, testing level, I/O level and hardware level. Every level is independent in logic and interact each other by interface and each level interior is assembly of software components which is related; VI component model defines interface stipulation of the components and internal structure etc, primarily realizes design reuse and process reuse of virtual instruments.This paper also discusses the VIS component building methodology, presents component building approach in C++ language and according with component model, and proposed the solution method of the problem of component heterogeneity, parking is used to solve the interface heterogeneity , and data dictionary used by data heterogeneity is to unify the data format. Finally, two examples are given, which prove that the method presented is feasible and effective.