Dynamic stability and control of tripped and untripped vehicle rollover 4. Stability of tripped vehicle rollover 4.1. Roll index of tripped vehicle rollover 4.2. Energy methods 4.3. Summary 6. Rollover control strategies and algorithms 6.1. Proportional integral derivative control method 6.2. H infinity control method 6.3. Model prediction control method 6.4. Linear quadratic regulator control method 6.5. Sliding mode control method 6.6. Summary 7. Conclusions. 3. Stability of untripped vehicle rollover 3.1. Roll index of untripped vehicle rollover 3.2. Rollover warning 3.3. Summary 2. Dynamic model of vehicle rollover 2.1. Roll plane model 2.2. Yaw roll model 2.3. Lateral yaw roll model 2.4. Yaw roll vertical model 2.5. Multi freedom model 2.6. Multi body dynamic model 2.7. Summary 1. Introduction 1.1. What is vehicle rollover 1.2. Risk of vehicle rollover accidents 1.3. Factors affecting vehicle rollover 1.4. Summary Vehicle rollover accidents have been a serious safety problem for the last three decades. Although rollovers are a small percentage of all traffic accidents they do account for a large proportion of severe and fatal injuries. Specifically some large passenger vehicles such as large vans pickup trucks and sport utility vehicles are more prone to rollover accidents with a high center of gravity (CG) and narrow track width. Vehicle rollover accidents may be grouped into two categories: tripped and untripped rollovers. A tripped rollover commonly occurs when a vehicle skids and digs its tires into soft soil or hits a tripping mechanism such as a curb with a sufficiently large lateral velocity. On the other hand the untripped rollover is induced by extreme maneuvers during critical driving situations such as excessive speed during cornering obstacle avoidance and severe lane change maneuver. In these situations the forces at the tire road contact point are large enough to cause the vehicle to roll over. Furthermore vehicle rollover may occur due to external disturbances such as side wind and steering excitation. Therefore it is necessary to investigate the dynamic stability and control of tripped and untripped vehicle rollover so as to avoid vehicle rollover accidents. In this book different dynamic models are used to describe the vehicle rollover under both untripped and special tripped situations. From the vehicle dynamics theory rollover indices are deduced and the dynamic stabilities of vehicle rollover are analyzed. In addition some active control strategies are discussed to improve the anti rollover performance of the vehicle 5. Active control for vehicle rollover avoidance 5.1. Anti roll bar system 5.2. Active suspension system 5.3. Active steering system 5.4. Active braking system 5.5. Integrated chassis system 5.6. Summary