Why bother transferring between a bus and a train, if you could just stay in one vehicle that travels on both roads and tracks? That's the thinking behind a new dual-mode vehicle (DMV), which is slated to begin operations in Japan on December 25.
In development since 2002, the DMV system is now being run by Japan's Asa Coast Railway company. It currently incorporates three vehicles, which will travel approximately 123 km (76 miles) between the Awa Kainan Bunka Mura cultural facility in Tokushima prefecture to the Umi no Eki Toromu marina in Kochi prefecture.
Each DMV is a modified diesel-powered bus that can carry 23 passengers (18 seated, four standing) along with the driver. When on the road, it simply moves along on its tires like any other bus. Once it straddles the rails of its DMV-specific track, however, the push of a button causes front and rear sets of steel rail wheels to deploy from its underside.
The vehicle's front tires are lifted entirely clear of the track, while the rear set stay in contact with the rails to provide propulsion. It can then manage a top rail-mode speed of 80 km/h (50 mph), although in practice it will stay at a cruising speed of 60 km/h (37 mph).
Along its seaside route – which is intended largely to cater to tourists – the DMV will change modes twice. The whole mode-changing process reportedly takes just 15 seconds. For safety reasons, the vehicle won't be utilizing existing rail lines that are currently used by trains.
According to Asa Coast Railway, the DMV's ability to run much of its route on tracks should make it considerably more fuel-efficient and less polluting than traditional buses. It should also require less maintenance, plus it could conceivably help transport people in the event of an earthquake or other disaster, in which either the highways or the rail lines were impassible.
The company additionally claims that the DMV will be the world's first dual-mode bus to enter public use. While this may be true, railroad maintenance trucks have been utilizing the same technology for decades. Additionally, both Unimog and BladeRunner have been developing dual-mode passenger- and cargo-hauling vehicles.
Source: Asa Seaside Railway
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There were train rule problems, because there was incompatibility between trains and buses crash safety.