Design of Man-Machine-Interface System for the Central Control System in LHD

A n1an-n1achine-interface (MMIF) system which is a primary component of the central control system for LHD has been specified. The MMIF system, here, involves a variety of intelligent functions needed in the LHD experin1ents as well as a scheme of graphical user interface in a narrow sense. The MMIF system provides a variety of information transmission through LAN. While LHD is a plasma physics experimental device, it has a specific feature of a large-scale plant due to a steady-state capability and cryogenic systen1s. The control system of LHD is, therefore, required to cooperate a number of component devices/facilities and should be reliable, flexible and extensible. Composition of conservative hard-wired logic control with a progranm1able logic controller and the MMIF system with a client/server system fulfills these requirements complementarily. The central control system has been designed to operate LHD safely without help of the MMIF system and hard-wired logic has priority over information transmitted through LAN, however, the MMIF system greatly facilitates procedures of experimental set-up, supervision of facility condition and sequence control. It also contributes to prevent operational human errors and consequent accidents. Major functions of the MMIF system are (I) Control of experimental sequence, (2) Conduction of experimental set-up on component devices/facilities, (3) Supervision of status of con1ponent devices/facilities. The architecture of platform of the MMIF system is shown in Fig. 1. All manipulation and indication are conducted in human friendly graphical environment on client