The limits imposed by oil reserves, global warming, road space and air pollution are a great challenge for mass transportation in densely populated cities. A compact two seat electric vehicle, only 1.7 m long and 1.2 m wide, with an empty weight of only 45 kg without batteries is possible through a revolutionary structure. The innovation consists of a light but strong sandwich plate with a foam core, to which the 4 wheels and two seats are attached. The cabin has the function and shape of a large safety helmet and is made of EPP foam with exterior reinforcing. Instead of doors the entire cabin is lifted up from the platform and swings back. The brushless DC motor with permanent magnets has a mechanical power of 1250 W. On a flat road only 360 W electrical are needed at a top speed of 24 km⁄h. Steering is with a mechanical “joystick” equipped with a lever for braking and a sliding sleeve for power control. Safety, also for pedestrians and cyclists, is assured by the foam cabin and fast braking with the hand.

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Electric wheelchairs that are in use have heavy weight and are difficult to maneuver in the home. Therefore, a study to establish simple movement in the home of people who have difficulty with walking because of advanced age was designed and developed. In this study, the following points were examined with 5 physically unimpaired people: (1) levels of back and arm muscle activity at the time of sitting⁄standing movement with various seat heights, and (2) a comparison of the muscle load of the arms during the operation of a manual wheelchair and an electric wheelchair. In the results, for the ergonomic design of a wheelchair for people having difficulty walking and who cannot use the muscular strength of lower limbs, the height of the seat of the wheelchair should be set to around 42-44cm without lowering it. Also, the useful support of the arms at the time of sitting⁄standing from the wheelchair should be given attention.

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The main objective of the project is to initiate activities connected with hydrogen utilisation in transport. Advanced technologies are utilised in order to optimise energy flows - the main energy source is electricity generated by fuel cells (50 kW). Other parts are accumulator and an ultracapacitor used for recuperation. About 20 kg of pressurized hydrogen (35 MPa) will be stored in pressure vessels, which will be mounted on the bus roof. The hydrogen bus as well as the first hydrogen filling station in central Europe is going to start in spring 2009.

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Recently, there have been many proposals and countermeasures for the purpose of the global environmental protection. Solar cell, windmill and fuel cell using clean energies are actively applied to home generation of electricity instead of using fossil fuel. However, teaching materials that are easy to understand regarding the use of clean energies are not generally used in elementary schools. Handicrafts and experiments using clean energies are especially required at early time of schoolchildren. This paper proposes handicrafts using solar cell, windmill and fuel cell suitable to address schoolchildren's needs. This paper deals with solar cells operated chain tower and merry-go-round, and wind power operated propeller type and signboard type windmills and Ferris wheel powered by a fuel cell.

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A DC-DC converter is designed according to the request of the electric propulsion system for a fuel cell sightseeing car. The converter adopts a simple topography - full bridge circuit. The main switch transistors are driven by the module TL494, based on pulse-width modulation method. A high accuracy linear optical coupler is used to isolate analogy signal in order to guarantee the stabilization of the converter. Experiments show that the converter can satisfy the requirements of the power match between the fuel cell and the motor under the ordinary operation conditions.

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Energetic Macroscopic Representation (EMR) is an energy-based graphical modelling tool to describe complex electromechanical systems. It is based on the action-reaction principle to organize the interconnection of sub-systems according to the physical causality (i.e. integral causality). Moreover, an inversion-based control can be systematically deduced from EMR using specific inversion rules. The aim of this paper is to introduce the basics of EMR approach and its inversion-based control. An Electric Vehicle with an electrical differential is studied as a simple example.

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New flux-switching permanent magnet (FSPM) brushless machine topologies with different stator and rotor pole combinations (N_s⁄N_r) are developed, with potentially reduced stator and rotor pole numbers without introducing the unbalanced magnetic force. The relative merits of FSPM and flux reversal permanent magnet (FRPM) brushless machines are evaluated. The electromagnetic performance, including back-emf, static torque, cogging torque, stator and rotor iron losses and magnet eddy current loss, and unbalanced magnetic force, etc. of new FSPM machines having N_s⁄N_r =12⁄16 and 6⁄8 is also compared with that of existing FSPM machines having N_s⁄N_r =12⁄10 and 6⁄5 by finite element analyses and experiments.

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1st report describes the educational activities using small-sized three-wheels and compact four-wheels vehicles. The latter was converted from gasoline engine to electric. The extracurricular activities using such vehicles were the Eco-power race conducted in Kochi prefecture in 1997 and the Electric Vehicle Rallies in Shikoku Island in 1997-2000. After such extracurricular activities, our laboratory has conducted the design education considering experiences in the real world. One of the most promising experiences as mechanical engineers is a creation of thought to design and produce products such as vehicles. Vehicles produced were small-sized hand-made four-wheels electric vehicles, electric motorcycle, tricycles, and motor-powered tillers. Since design is of great importance to produce products such as vehicles, 3D-CAD learning is firstly recommended in our laboratory before starting the design and manufacturing of products. In this report, the latter half regarding the laboratory activities is described.

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Liquid Cooled High Power Braking Resistors - LCHP Series, 5 kW to 150 kW. This range of resistors has been aimed for as break resistors for fuel cell and hybrid vehicles but has the capability to be used in various industrial high-power applications whereever liquid cooling is available. The resistor and termination enclosure is made of in thermal plastic and is protected according to IP65 allowing the resistor to be mounted externally as well as internally. The LCHP series offers a very compact (sandwich) design and weight much less as conventional metal constructions. The enclosure is inherently an electrical insulator providing increased safety. The construction will also overcome the problem of capacitance, which is a problem in metal assemblies. Power handling capability is related to the coolant medium and the temperature as well as to the flow rate provided.

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