Thrill Rides
In 1991 Force Engineering designed and supplied Linear Induction Motors to Disneyland Paris for The Big Thunder Mountain Railroad roller coaster ride. The LIMs are used for braking the train during and at the end of the ride but also move trains in and around the storage area. These motors were hermetically sealed and have required little or no maintenance since installation.
In 1996 Force Engineering changed the future of the industry by developing a Linear Induction Motor catapult launch system to replace mechanical drives in conjunction with a leading and innovative US based ride manufacturer.
Alternative launch systems accelerate the train by a rope haul or tyre drive system. The rope is either connected to a massive falling weight or to a massive flywheel and clutch. Tyre drives use a large number of tyres set in motion and then brought in contact with the ride vehicle to propel it forward. These are both high maintenance systems.
LIM launches are instant via contactless drive on the ride train itself. Typically a 80m (250ft) launch track is lined with double sided LIMs and the vehicles carry lightweight aluminium fins acting as motor reaction plates. The LIMs are powered in sequence to accelerate the 13m (40ft), 7 tonne train horizontally to a speed of 55mph in less than 4 seconds. Peak acceleration is more than 1g. This is an exhilarating experience. LIM thrust varies from 8kN (1800lb) per double sided pair at low speed to 2kN (450lb) at high speed. Motors vary in length from 1.2m (3.5ft) to 2m (6.7ft). Acceleration is horizontal so the vehicle gets kinetic energy initially and then converts this to potential energy to gain height in loops on track.
The same technology was later used to launch vehicles to 70mph on 9 rides in USA - and the first LIM catapult system outside USA was opened in 1998 in Japan. The launch technology is exceptionally reliable with no moving parts.
LIMs generate force without contact so additional boost or brake LIMs can be added anywhere on a ride. Certain rides feature inclined or vertical lift sections at the end of the track, where the train is lifted 14m (45ft) vertically to increase its potential energy for a return run. This was a unique ride element and made completely new designs of coasters possible. 15 coaster launchers had been supplied worldwide to the end of 2009.
These catapult systems use up to 5MW electrical power, but only for a very short time. Energy cost is typically less than US $1 per launch.