11.8  Suspension and steering geometry

The double wishbone suspension and the steering linkage of a car, as linkages. The wishbones as a four-bar linkage seen from the front: camber gain, roll centre and the path of the wheel as it moves up and down. The motion ratio between wheel and shock absorber, which sets the wheel rate \(k\,\mathrm{MR}^2\) and wheel damping \(c\,\mathrm{MR}^2\) used in Springs and dampers. Steering: the Ackermann condition that the inner wheel turns more than the outer so that both roll about one centre, the trapezoid linkage that approximates it, and bump steer. Example: the front corner of the RC car, measured, modelled in Python and checked in the motion solver of Simulating mechanisms in Python.