Two-Wheel Self-Balancing of a Four-Wheeled Vehicle [Applications of Control]

Cars and trucks are susceptible to accidents due to rollover. In the United States in 2005, 21.1% of a total of 54,718 deaths in vehicle crashes were caused by rollover [1]. Significant research has therefore been de voted to detecting and preventing rollover through active control. Numerous approaches attempt to detect or pre dict wheel liftoff using onboard sensing and a combina tion of automatic steering and braking to keep the wheels on the ground [2]-[4]. Rather than focusing on how to keep the wheels on the ground, it is also useful to under stand how to control a vehicle while two wheels are in the air. This understanding may enable the design of control laws that can safely return the vehicle to the ground after inadvertent tip-up.