Optimization and cost-effectiveness for estimating shock absorber states

The role of the hydraulic shock absorber is to damp oscillations and
absorb energy which has a direct impact on the driving. Öhlins Racing
has succeeded to produce a sophisticated semiactive technique; CES
(Continuously Controlled Electronic Suspension), where the damper is
controllable and therefore adaptable for various driving situations.

With the knowledge of difficulties in detecting useful information about
the damper-velocity at high frequencies, the aim of the thesis is to find a
method which can improve the estimated velocity of a damper mounted
on a motorcycle. Sensor fusion is a method which takes multiple measurements
into account in an effort to reach an optimal estimate.

The results showed that a Kalman filter which estimated the dampervelocity
generated useful information about the sprung and the unsprung
mass of the motorcycle. By measuring the position and acceleration
of the sprung and the unsprung mass, time delays that are
retarding the system could be reduced.