There are many navigation instruments available to provide increased safety and economy for ocean voyage. Especially in recent years the rapid advances in semiconductor and microprocessor technology have made possible the development of dedicated and automated equipment for commercial shipping.
Initially, individual unit such as Loran C, Omega, Satnav and Decca receivers were developed. Other equipment including ARPAs, loading computers, stand-by sequencers and computer loggers were also introduced separately.
Presently, these instruments are being combined into integrated systems, taking advantage of graphics displays and improved control theory. One such system, the Total Nabigation System is introduced here. This system will concentrate a number of functions at the bridge and facilitate safe and economical navigation. The system consists of following functions: Optimum planning aids, Automatic position fixing, Route tracking, ARPA, Engine performance display and Hull motion display.
For a Total navigation system, accurate ship's position information is necessary and important. However, nowadays there is no navigation system which provides worldwide, 24 hour coverage with precise position.
GPS, the Global Positioning System is being developed by the U. S.. This satellite system will be the ideal position fixing system. It will have various applications for marine use as well as for land and aircraft. The GPS receiver for marine use is also introduced in this paper.

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“Hakuho Maru” was delivered to the Ocean Research Institute of the University of Tokyo in May, 1989. She is a sophisticated “multi-purpose” oceanographic research vessel, and her tasks are varied in many fields; geology, geophysics, meteorology, physical oceanography, chemistry, biology, and fishery science. In order to achieve these tasks, she is equipped with the following special systems.
(1) Electric Propulsion System
(2) Machinery Part One Man Control System
(3) Joystick Control System
(4) Integrated Navigation System
(5) Optical Data Network
(6) Data Processing System
These systems are introduced in this treatice.

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Many ideas to diagnose the propulsion plant have been proposed so far. Among them, expert system using AI (Artificial Intelligence) technique has become a great interest lately. The diagnosis by pre-assumed scenario of phenomena has been dominantly applied to expert system, however, this application of expert system has its limit in applicability due to the following disadvantages.
(1) As the knowledge base in the system becomes larger, the process time becomes longer and the maintenance of the knowlege base extremely difficult.
(2) It is practically imppossible to clarify all possibilities of case-result combinations in the knowledge base.
Our ideas to solve these disadvantages in the above application are:
(a) To express the inference of expert (Dynamic Knowledge) by a production rules,
(b) To express the knowledge concerning structure and function (Static Knowledge) of the system by an object model,
(c) To create fault set in the object model dynamically.
We, hereafter, would like to explain our expert system for failure diagnosis of marine diesel engine start-up.

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Mitsui-B&W L-MC type engines were, at first, delivered with Woodward type mechanical-hydraulic governor. But when S-MC type, much longer stroke version of L-MC type, was developed, Mitsui decided to use the electronic governor instead of the conventional ones because high possibilities of “hunting” problem and “jiggling” problem were anticipated.
In a way to choose the electronic governor type, the high cost of the electronic governor was one of the major factors to be considered. By comparing the prices of various governors Mitsui realized that it would be better to develop a governor by himself.
The electronic governor consists of “controller” part and “actuator” part. A microprocessor is used in the controller and it gives many additional features to its basic function of speed control of the engine. Compared with the conventional mechanical-hydraulic governor, one advantage of the electronic governor is such additional features, and the other advantage is easy adjustment. The Mitsui type actuator has a unique configuration among those of the other electronic governor suppliers. It consists of a hydraulic cylinder, a solenoid value, a flow control valve, and 2 potentio meters. In order to make the hydraulic pressure, 2 air driven booster pumps are used.
Since the first S-MC engine, many Mitsui type electronic governors have been delivered and lately L-MC engines are also equipped with this governor.

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