Automated People Mover (APM)
[ 18 cities presented here ] (most recent entries: Feb, 19th, 2017)
The recent tendency in dedicated urban transports (e.g. airport connections, amusement parks internal connections, etc) is going towards the so-called "automated people movers" (APM), characterized by short rolling stock (and, consequently, short stations), high frequencies and driverless operations.
These systems don't require any driver on board, an, generally, any permanent workers at the stations (except, in certain cases, for security and hospitality services) or along the track. The system supervision is managed by a central control place, often located in the maintenance area.
The automation system is based on the classical ATO, ATP, ATS architecture managed automatically by a specific software that works on the information provided by a signaling system located along the track (track circuits, transponders); this allows the train detection on the track and the speed control in order to warrant the safety conditions and the precise respect of the planned timetables.
As previously said, generally no permanent workers operate in the stations or along the line; safety and communications (on board and at the stops) are provided by video and audio systems that allow to exchange information between passengers and the central control place at all times. Platform doors are one of the peculiar elements of most of the APM systems; platform doors are opened only during the boarding phases, segregating passengers from the track.
Driverless monorails are a particular type of APM. The monorail is a transport system based on a single track (mostly on viaduct, with possible ground level or underground applications), which supports straddle or suspended vehicles, wider than the monorail beam. These systems offer remarkable cinematic performances (low horizontal radius, high vertical gradient) with low environmental impacts, thanks to the adoption of light infrastructures: for all these reasons monorails have many applications in amusement centers, parks, zoo and tertiary high tech districts. In the latest years, thanks to the success of some applications and to the continuous technological improvement, monorails have been often used also as urban transport systems.
Driverless cable-system are another particular kind of APM. The track of the modern cable systems is constituted by a series of stations, each one connected the to next one by a cable ring. These systems have many analogies with the classical funiculars; they are constituted by the following main elements: cable, motorized station, return station, tensioning station, vehicles.
The cable is moved by an electric winch and it's set from a return to a tensioning station; intermediate stations are located between these terminals, along a route that allows different types of sections (straight, curved, inclined), thanks to specific mechanical rollers (straight rollers for straight or vertically convex segments, inclined rollers for horizontal curved segments, other rollers for vertically concave segments). The winch generates the cable motion, which is transmitted to the vehicles by some pliers which lock them to the cable.
In the return station (mostly coinciding with the motorized station), a pulley keeps the cable in the correct configuration. The possible imbalances of the cable in the tensioning station at the opposite side of the track are recovered by an hydraulic system.
The vehicles are linked to the cable by a fixed or temporary grip, and they are guided by horizontal wheels which runs along horizontal guide beams, on each side of the running platform; thanks to the absence of on-board engines, vehicles have low noise emissions and a low weigth. The latter factor, combined with the cable traction, allows to overtake strong vertical gradients (in same cases more than 15%). In "temporary grip" cable systems a turning platform allows the vehicle inversion at the terminals, so that they can return in the opposite direction with the doors located in the external part of the track. Single track option (if adopted) needs some vehicle crossing sections (double track by-passes).