The term ‘PeopleMover’ needs little explanation – we are dealing with technology that moves people from point A to point B efficiently. However, as usual, the means of transportation is worth studying in greater detail, particularly considering the significant differences between the original, Disneyland version, and the WDW one (now known as the Tomorrowland Transit Authority)

As I mentioned in the OmniMover article, the original PeopleMover was designed for the 1964-65 World´s Fair, much like the majority of early Disney technologies. This early form used continuously rotating wheels or tires to roll the vehicles along the track. However, the problems with inertia I mentioned previously led to a serious rethink of the PeopleMover concept by the time the Magic Kingdom was being constructed. Instead of pacer wheels (which we more suited to roller-coaster design than flat track operation), the new PeopleMover (or WEDWay) would use embedded electric motors, allowing a primitive speed control and the ability to stop and start the vehicle chain without major issue. These motors are known as linear induction motors.

The actual concept of a linear motor stems from research all the way back in the 1840´s by Charles Wheatstone of King´s College, London, England. However, the modern motor is closer in style to that developed by Professor Eric Laithwaite of Imperial College, London, approximately 100 years later. In his model, the motor is continually generating a moving magnetic field in a straight line, rather than the usual circular motion. The vehicle has a metal plate positioned in line with the motor, which is temporarily magnetized by the field. The two fields oppose one another, and as a result the vehicle is pushed along the track, away from the motor. If studied carefully, the vehicle will be seen to levitate over the motor, hence the alternative name for the propulsion system, Magnetic Levitation (or MagLev).

By altering the strength and speed of the magnetic field changes, the speed of the vehicle can also be changed. The vehicles can also be made to stop suddenly if necessary, by setting the motors to attract the metal plate. As a consequence, this technology is now also used as an alternative to chain lifts on roller coasters, such as California Adventure´s California Screamin´, as well as acting as an alternative to the contact braking device on such rides.

For reasons of simplicity, I have omitted a lot of detail about linear induction, but if you want to find out more, many textbooks on physics and electromagnetism will include some detail on the subject, or alternatively you can visit http://en.wikipedia.org/wiki/Linear_motor, which acts as a jumping off point to more information on electric motors as a whole, as well as some other non-Disney applications of the technology.

Photos by Tim Devine, courtesy TheMagicInPixels.com. Used with permission.