MAN-MACHINE INTERFACE SYSTEMSFOR LHD EXPERIMENTAL OPERATION
K.Y. Watanabe, H. Yamada, H. Ogawa, N. Yamamoto, N. Taniguchi, K. Yamazaki,NIFS, Toki, Japan

Abstract
A man-machine-interface system, we call LMS (LHD
Man-machine-interface System), is a primary componentof the central control system for LHD (Large HelicalDevice). LMS involves a variety of intelligent functions.
LMS consists of 3 Layer model, Presentation,Transmission and data house, and Device Control Layers,which correspond to LMS clients, LMS servers and Subsystems. At the end of 1998, 8 LMS clients, 2 LMS
servers and 6 Sub-systems are running.

1 INTRODUCTION
The large helical device (LHD) [1] is a superconducting toroidal facility with a mission to steady-state
operation of high temperature plasmas to magnetic
fusion research. The major radius, the minor radius ofplasmas, and the designed toroidal field are 3.9m, 0.65m,and 4T, respectively. While LHD is a plasma physics
experimental device, it has a specific feature of a largescale plant due to a steady-state capability and cryogenicsystems. The facilities composing LHD are arranged into30 sub-systems, e.g., a vacuum pumping unit, a power
supply for super-conducting coils and ECRF heatingunits, etc. Major sub-systems have their own control
computers, and can be operated independently andprotect themselves.
The control system of LHD [2,3] is required to cooperate a number of plant component devices/facilities(sub-systems) as well as manage flexible plasma
experiments. Also safety protection against all expectedoccasion and easy extension for up-grade are key issues.
The control system of LHD should be, therefore, reliable,
flexible and extensible. Composition of conservative
hard-wired logic control with a programmable logic
controller and the man-machine interface (MMIF)
system with a client/server system fulfils theserequirements complementarily (see Fig.1). The central
control system has been designed to operate LHD reliably
without help of the MMIF system and hard-wired logic
has priority over information transmitter through LAN,
however, the MMIF system has various intelligent
functions, which leads to flexible and extensible system,
and contributes to prevent operational human errors andCentral Control System

Man-Machine- Interface SystemLMSCentral Control Device
PLC,VME
Relay circuit

Safty
Flexible
ExtensiveReliable

Control of exp. setup

Client/Server
systemSupervision

Opticalfiber

RelaysignalInformation retrieval

Protective interlock
Exp. sequence

LANIndication

Timing/Trigger

Timing/trigerHard-wired Mode management
logic
operation consoleExp. sequence
Timing/Trigger

Remotemanipulation

Mode management

computer terminals

30 sub-systems
Figure 1 Position and role of LMS in central control system

TCP/IPGUI terminals
WindowsNT
VisualBasic

Presentation Layer
Ethernet

SQL*netTCP/IP

LHD Operational Information
Cluster
Transmission andData House Layer
Database ServerWindowsNT
Oracle 7

TCP/IP

LHD Device Control Cluster
Ethernetsupervision dataparameter setting

Device ControlLayer

sub-system

sub-system

sub-system

UNIXVXWorks

MS Windows

Figure 2 Architecture of LMS.
consequent accidents by human friendly graphical userinterface (GUI).

2 MAN-MACHINE-INTERFACE SYSTEM

The numbers of subsystem and parameters to becontrolled are 30 and more than 300, respectively. Heremajor parameters have physical meanings andsubstantial set-up of each device conducted by anindividual control computer based on transmittedcondition. Set-up procedure should be done within 90 sec.
While users can write out candidates of experimental
condition sets and store them. The set-up data sets aremanaged with database systems. Scheduling candidatesof experimental condition sets is also done.
(3)
Supervision
ofstatus
ofcomponent
devices/facilities.
This system does not have own data acquisition systembut integrate monitoring data from a number of subsystems through data transmission. Although the data areprimarily representing ones to watch status of whole
LHD system, the number reaches 3000 in total. When an
accident is detected by the central PLC, information
related to the cause of the accident is accumulated indetail with this function.
The architecture of platform of the MMIF system isshown in Fig.2. In LMS, 3 layers model is applied. All
manipulation and indication are conducted in humanfriendly graphical environment on client terminals (apresentation layer). A server manages information
between client terminals and control computers forcomponent devices/facilities with a relational database (atransmission and data house layer). It should be here
noted that LMS does not directly control component
devices/facilities, but conduct them through each controlsystem for component (a device control layer).
We have organised LMS on so-called de facto standard
so that it can develop along with rapid progress incomputer application fields. The network OS, relational
database managing system (RDBMS) and GUI
development environment in LMS are WindowsNT,
ORACLE 7, and VisualBasic.

A man-machine-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 theLHD experiments as well as a scheme of GUI in anarrow sense. The MMIF system provides a variety ofinformation transmissions through LAN.
Major functions of the MMIF system are the following
three:LHD Experimental LAN(1) Manipulation of experimental
MMIF Client
sequence and operational mode
Router/Fire Wallmanagement.
Operational Information LAN
The duration of discharge, theTCP/IP,NetBEUI,interval of each pulsed discharge andMMIF
Router Apple Talk
Routeroperational mode transition are set from Peripheral Device
ServerTorus Device
the graphical terminal by a permitted Control LANControl LANoperator. Sequential procedure ofTCP/IP
TCP/IP
ECH
experimental set-up is also managed.
NBIDiag.Dev.
Cryogenic Coil Power Torus
Contr.
Contr. Contr./etc.
Contr.
Usual users can check the status of
Supply Contr. Supervision
Subetc.
etc.
LHD experiment on client computers.
systems
In LHD, Physical acquisition data is
managed with an experimental index,
Diagnostics
so-called Shot Number. It is also
devicesFDDI
NBI Device
managed.
LHD
Ehernet(2) Management of experimental set- ECH Device
up on component devices/facilities,
Figure 3 Schematic draw of LHD operation LANTransmission between GUI terminal and a server isdone by a database access protocol (SQL*net) to promote
efficiency in database access. A socket transmission onTCP/IP is also used for event-driven action andsynchronisation of sequential procedures. The
transmission protocol between the server machine andthe sub-system is limited to TCP/IP, since a variety ofcomputers are utilised for the sub-systems.
The information data in LMS is transmitted throughLHD operation LAN. The LHD operation LAN is one
component of the LHD experimental LAN, on which theinformation of LHD experiment is transmitted. TheLHD experimental LAN consists of three sub-networks(clusters), i.e., operation, analysis and plasma dataacquisition clusters. The LHD experimental LAN is
designed based on a concept that the data with different
purposes are transmitted on a independent cluster inorder to transmit the network data reliably and safely,
and to control network traffic. The LHD operation clustercomposes an operational information LAN. Torus device
and peripheral devices control LAN’s. Informationexchanges for operation and discharge condition,
management of the sequence of experiments and plasma
discharges are conducted on these LAN. In order to keep
security of the whole LHD operation LAN clusters, thefirewall system which controls security in the level ofnetwork application software carefully is employed on
the upper network streamside.

3 SUMMARY
Reliable protection of super-conducting coils andflexibility for plasma physics experiments are
simultaneously prerequisite to the central control systemfor LHD. In order to fulfil the requisite, we have applied
the composition of conservative hard-wired logic andinformation transmission by client/server system with
LAN, so-called LMS to the central control system.
The planning of LMS started at F.Y.1995. It took
about 3 years to fix the specification, to examine theperformance of basic architecture by prototype systems
and make an application code. LHD experiment started
at March of 1998. LMS have been applied since thebeginning of LHD experiment.
In 1st experimental period (1998/3-5), 2 clients, 1
server and 3 controllers of sub-system were running. The
following functions were running; (1) presentation ofstatus of experimental condition, sequence and events,(2) writing-up and setting-up of experimental condition,(3) supervision of plant data from sub-systems. 2 clients,
1 server and 3 controllers of sub-system were running.
The following functions were running; (1) presentationof status of experimental condition, sequence and events,(2) writing-up and setting-up of experimental condition,(3) supervision of plant data from sub-systems.
In 2nd experimental period (1998/9-12), 8 clients, 2servers and 6 controllers of sub-system were running.

The following functions were running additionally; (1)management and presentation of experimental condition,(2) management of shot number (experimental index).
The development is in progress. There are thefollowing future subjects; (1) addition of connection withmore sub-systems, (2) manipulation function ofexperimental mode transition and experimental sequence,(3) retrieval function of experimental condition, (4)improvement of presentation of status of experiment, (5)improvement of experimental condition management
function.

REFERENCES[1] O.Motojima et al., Fusion Engr. and Design 20(1993) 3.
[2] K.Yamazaki et al., Nucl. Instr. and Meth. in Phys.
Res. A 352 (1994) 3.
[3] H.Yamada et al., Fusion Tech. 96 (Proc. 19th Symp.
on Fusion Tech. 1996) p.945 (1997)