Embedded electronic control system for continuous self-tuning of motorcycle suspension preload

Comfort and safety of vehicles significantly depends on the behavior of the suspension system. This is particularly true in two-wheel vehicles where the equilibrium is fundamental. Variations of the static load on the vehicle determine a compression of the suspension spring that modifies the static equilibrium point with respect to the optimal value. The system we describe is capable of continuously correcting the suspension preload of a motorcycle without user intervention, in order to compensate the load variations. The electronic system is based on a microcontroller and a linear position sensor that measures the suspension stroke. It executes a closed-loop control algorithm that adjusts the preload and maintains the average value of the suspension stroke constant. The experimental results coming from road tests performed on a scooter are reported and discussed.