thumb|upright=1.4|Finding the roll center of a [[MacPherson strut]]
The roll center of a vehicle is the notional point at which the cornering forces in the suspension are reacted to the vehicle body.
There are two definitions of roll center. The most commonly used is the geometric (or kinematic) roll center, whereas the Society of Automotive Engineers uses a force-based definition.
Definition
- Geometric roll center is solely dictated by the suspension geometry, and can be found using principles of the instant center of rotation.
- Force based roll center, according to the US Society of Automotive Engineers, is "The point in the transverse vertical plane through any pair of wheel centers at which lateral forces may be applied to the sprung mass without producing suspension roll".