A Study On Component-based Human Machine Interface (hmi)

With the development of industrial control technology, the demand of HMI (Human-Machine Interface) is increasing quickly, but its development methodology is used to provide a dedicated HMI for the specific application. This method of development is inefficient, and the maintenance is costly, so it has become unsuited to today's embedded software development. The component technology is efficient and trustworthy; it has been widely used in the traditional software development, and has started to be used in the embedded field. By analyzing some generic component models and embedded component models, and combining the characteristics of HMI, the paper designed an embedded component model called CCS Model.The article describes the HMI's working principle, characteristics and composition methods of hardware and software, lists three kinds of current generic component models, including COBRA, COM/DCOM, EJB, and pointes out the reasons of that the generic component models are inappropriate in the embedded systems. And analyses the excellent embedded component models, including Koala, PECOS, CCOM, discusses the advantages and disadvantages of these component models, and shows the reasons of that they cannot be applied to HMI directly, according to the characteristics of HMI. By analyzing the above component models, presents an embedded component model for HMI, called CCS. The definition of the CCS is forming the following aspects:(1) The method of defining the model elements. The CCS is divided into five elements: Component Body, In Port, Out Port, Connection Bridge and Function. The paper introduces the method of how to define the 5 elements and their characteristic, and gives the relationship of them.(2) The defining ways based on the nature of language-independent. Designs three kinds of definition languages which are nothing to do with Programming Language, including Interface Language, Connection Bridge Language, Component Language, and then to achieve the independent platform.(3) The combination method based on Data Stream. Describes the method of components combination based on Data Stream, and gives 4 kinds of combination method: the Sequential Combination, the Using Combination, the Choosing Combination, the Cooperation Combination.(4) The reusing method based on source code. Describes the two ways of reusing method based on source code, and improves them in the CCS.Finally, shows the methods of that the CCS used in the HMI, including the following aspects:(1) Introduced the five parts of the CCS's HMI, including: The Graphical Interface Design System, The Engine System, The HMI Data, The Boot Loader, and The Engine Component Configuration System.(2) Introduced the method of the engine reconfiguring, for example, design the communication protocol components.(3) Introduces the three steps of designing HMI by The Graphical Interface Design System: The Needs Analysis, The Interface Design and Validate the Design Results.(4) Develop the Text Display with the method.