Semi-Active Suspension Control on Bicycles: Anti-Dive during Road Excitation

摘要

Suspension systems on bicycles have a tendency to severe brake-induced dive-in, caused by the small wheelbase in combination with a high center of gravity. Semi-active dampers allow the implementation of anti-dive functionality, preventing this behavior. Experimental analysis has shown that this yields significant advantages during brake control on level surfaces. In the presence of additional road excitation, however, a strong conflict arises. A specific test case is a bump occurring while braking, when the damping is set to the hardest value in order to mitigate dive-in. A simulative analysis illustrates that especially the dynamic wheel load is affected, which during braking is safety critical. By simulation and experimental implementation it is shown that using a simple semi-active control rule a decent trade-off can be found. Finally, the influence of the actuator response time is evaluated.