Progetto di un ammortizzatore di sterzo per motocicli basato su fluidi magneto-reologici

The steering damper of a motorcycle has the function of reacting, with an adequate torque, to the uncontrolled oscillations that could be generated on the steering around the axis of rotation by a phenomenon of instability called wobble. The wobble is very critical for the safety of the motorcycle. On the other hand during normal use an high steering torque is extremely negative and causes tiredness and safety problems for the driver. The use of active and semi-active dampers with a variable damping characteristic can solve this trade-off problem. In this paper the design of a semi-active steering damper based on MR fluid and integrated in the sleeve of the steering block is presented. The proposed damper is able to generate torque values extremely low during normal use and besides to control the wobble phenomenon. The integration of the damper in the sleeve of the steering block also leads to a significant reduction in size.