ALWEG - Suspension
ALWEG-style monorails all have the same basic suspension. They have two suspension bogies, one at the front of each car and one at the rear. These bogies consist of pneumatic rubber tires on top for load and propulsion, and horizontal stabilizing rubber tires. These typically are at the top and bottom of the vertical portion of the beam. ALWEG and Hitachi monorails have the load tires either below or extending into the passenger cabins. This affords the "standard transit" methodology of being able to walk between the cars. The Disney/Bombardier design puts the load wheels in front of and behind the passenger cabin, so each car is isolated from the others.
The Seattle ALWEG monorail trains ride on dual pneumatic rubber
tires 39.5" in diameter and have horizontal pneumatic rubber
tires 25" in diameter for stability and guiding. The Seattle
trains have four sections each for a total of 8 load wheel pairs
and 8 stabilizing sets for a total of 64 wheels per train. The
tire were originally nylon tubleless. The bogies are self-contained
units consisting of load carrying and stabilizing components.
"Airspring" suspension smoothes the ride. The load-carrying
wheels are steered (for curves) by the stabilizing wheels to prevent
excessive tire treadwear.