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TECHNOLOGY ROADMAP: TRANSPORTATION

order to break this barrier, development happened trains essentially float on a cushion of air at very
in the field of magnetic levitation, in which, the high speed; it moves between two electromagnetic
driving force of the train is not transmitted fields, without physically touching the rail track and
through friction, but through electro-magnetic doesn’t use any fossil fuel to run. Since Maglev
force available through linear motors, and the train train does not carry engines and the equipments
floats on guides while in motion. As the force and such as transformers, inverters and wheels thus
power requirements are quite large, needing huge make light weight and hence no adhesion or
currents, superconductivity is needed for reducing friction problems. In addition, superconducting
the losses. The pioneering work was done by magnets makes it capable of harnessing large
Japan and experimental models with tests speeds propulsive power. Images of Maglev trains are
of close to 500 km/h were achieved. However, given in Fig 2.2.
due to exorbitant cost of track, rolling stock and
associated technologies, maglev technology has Maglev technology has received the most
not proliferated as a mode of rail transportation attention, particularly in North America, as a result
commercially. This could be the reason for many of its ability to greatly reduce its environmental
countries in Europe and also Japan, to do further impact on surrounding communities. Germany
research in the rail-wheel friction technology, and Japan are the pioneer nations in utilizing
which resulted in increasing the speeds beyond Maglev technology. Japan has developed the High
the earlier barriers and reaching 250, 300 and 350 Speed Surface Transport (HSST), while Germany
km/h, and France (TGV) ultimately achieving the has developed the Transrapid system. Recently,
record test speed of 574.80 km/h in 2007. Japan has been promoting a newer version of the
Maglev known as the superconducting Maglev
In view of the above developments, in the technology[10].
Indian context, at least for the present and near
future, rail-wheel friction technology would be 2.1.2 Riding Comfort and Tilting Technology
the feasible solution for high speed commercial The tilting technology has now become a
operation, though, this too is quite expensive. Use requirement for high speed operation. When
of lightweight materials, designs providing low the train travels at high speed curved tracks,
aerodynamic drag, tracks with very low curvatures, particularly on existing railroad tracks, the coach
use of onboard mechatronics to reduce the senses the curves and tilts itself suitably to nullify
forces while train negotiates curves (like tilting the effect of centrifugal force. The advantage of
technology, self steering bogies etc) in order to tilting trains is that they can negotiate curves faster
keep the passenger comfort and derailment than ordinary trains, thus reducing the level of
coefficient within acceptable limits are some of the discomfort that passengers normally experience
mandatory requirements for high speed trains. otherwise. At the same time, this method reduces
the track forces which in turn improves the vehicle
2.1.1 Maglev stability at high speeds on curved tracks.
A detailed discussion on Maglev is not within the
scope of this report; however, for the sake of basic Switzerland and Great Britain are the latest among
appreciation, it is to be understood that Maglev the European countries to introduce tilting train

FIG 2.2(a): MAGLEV TRAIN FIG 2.2(b): COMPONENTS OF MAGLEV TRAIN

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