Computer-controlled Vehicle System

The Computer-controlled Vehicle System, almost universally referred to as CVS, was a personal rapid transit (PRT) system developed by a Japanese industrial consortium during the 1970s. Like most PRT systems under design at the same time, CVS was based around a small four-person electric vehicle similar to a small minivan that could be requested on demand and drive directly to the user's destination. Unlike other PRT systems, however, CVS also offered cargo vehicles, included "dual-use" designs that could be manually driven off the PRT network, and included the ability to stop at intersections in a conventional road-like network.

Work on CVS started in the late 1960s as a demonstration system for a "traffic game" at Expo '70. This demonstration was successful and led to a further development project in 1970, which expanded several times and eventually produced a large test track outside of Tokyo. However, in 1978, the Ministry of Land, Infrastructure and Transport declined to grant CVS a license under existing safety regulations, citing issues with the short headway distances. As other proposed CVS deployments also dried up, work on the project ended some time that year.

The concept of personal rapid transit (PRT) developed in the 1950s as a solution to the problem of providing mass transit in smaller urban areas and the suburbs of larger cities. Existing systems, heavy rail and subways, required major infrastructure and had high capital costs that limited their use to only the densest urban areas. Buses could run on existing roadways, but were thus subject to traffic problems and could not offer the high-speed services that made subways so attractive to riders. Modern PRT really began around 1953 when Donn Fichter, a city transportation planner, began research on PRT and alternative transportation methods. In 1964, Fichter published a book, which proposed an automated public transit system for areas of medium to low population density.

The solution appeared to be a "mini-subway", one that was small enough that the routes did not require the same sort of capital costs as a conventional system. However, using traditional technology to implement such a system would not work, as the required distance between vehicles on a subway system, known as headway, was often several minutes. This would mean a low vehicle density, and, if this was combined with a small number of passengers per vehicle, a very low overall passenger capacity. If such a system was to be practical, the distance between the vehicles had to be reduced, something that the emerging computer market appeared able to address.

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