Body roll is the axial rotation of avehicle’sbody towards the outside of a turn. Body roll occurs because thecompliance invehicle suspension allows the vehicle body, which sits upon the suspension, to lean in the direction of the perceivedcentrifugal force acting upon the vehicle.^[1]

Vehicle suspension allows a vehicle’swheels to move independently of its body. This smooths the ride for occupants and cargo while allowing the wheels to stay in contact with the ground over bumps.^[2] In a corner, therange of motion in the suspension allows the vehicle body to lean over toward the outside of the turn as the body tries to continue in a linetangential to the corner. Softer suspension with more travel will allow more body roll than harder suspension with less travel.^[3]

Body roll allows a vehicle’scentre of mass to move towards the outside of the turn, increasing theload transfer to the outside wheels. This can causeundersteer oroversteer to occur more easily than if body roll was not a factor. Body roll can also be uncomfortable for passengers and cause damage to cargo.

Anti-roll bars are suspension components designed to mitigate body roll. They do this by connecting the wheels at either end of anaxle with a torsion bar attached to the vehicle body. Body roll can also be reduced by lowering centre of mass of the vehicle body, fittingstiffer suspension springs and reducing thesprung mass of the vehicle.^[4]

• Weight transfer
• Vehicle rollover