Brennan monorail car

Brennan monorail car

[¦bren·ən ′män·ə‚rāl ‚kär]
(mechanical engineering)
A type of car balanced on a single rail so that when the car starts to tip, a force automatically applied at the axle end is converted gyroscopically into a strong righting moment which forces the car back into a position of lateral equilibrium.