Enhanced motion vehicle

An enhanced motion vehicle, or EMV, is a ride vehicle developed by Walt Disney Imagineering, a component of The Walt Disney Company, for use in amusement park rides located at Disney's theme parks. Riders are seated on a modified motion simulator base that is mounted on a wheeled chassis. As the vehicle travels through the attraction, the motion base simulates movement, such as driving over rough terrain or leaning through a turn, that makes the ride experience appear more realistic.

Disney filed for patent on the Enhanced Motion Vehicle ride system on November 16, 1995.

This ride system was developed for the Indiana Jones Adventure. Four such systems were built (in chronological order):

The Enhanced Motion Vehicles (EMV) are intended to appear as a battered military troop transport or "Time Rover". EMVs are driven less than 14 miles per hour (23 km/h) by air filled tractor trailer tires atop the surface of a slotted roadbed. Beneath the slot, a tubular guiderail guides the front wheelset and is responsible for supplying power to the vehicle, which is 480 volts in three phase, with a capacity of 200 Amps. The power is divided among the communications, control, safety, audio systems and the two motion systems - propulsion and hydraulics. Each transport can accommodate twelve guests with three rows of seats, four across, with the front left seat behind non-operational steering wheel. In addition to the three bus bars for power, there are three additional bus bars, one for a "GO" signal, one for a "NOGO" signal, and one for ground.

Each EMV is a motion simulator, or technically a 'full-motion chassis' because it is not under the control of the occupants, and it travels through a show building instead of enclosing occupants in a moving theater room, as in the case of Star Tours. The EMV motion base is attached by three hydraulic actuators to the frame of the chassis carrying the bulk of unsprung weight, allowing the low-mass body shell to articulate independently and rapidly with micrometer precision by incorporating a position feedback system. Three actuators are used on the chassis motion platform to position the motion base in six degrees of freedom: three thrust planes (x, y & z) with three rotational axes (pitch, roll, and yaw). A guest's physically intense experience is programmed to achieve the illusion of greater speed and catastrophic mechanical failure using the enhanced-motion vehicle's ability to add several feet of lift then rapidly descend, shudder and tremble, and intensify cornering with counter-bank and twist.

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