Stability Behaviour Based on Simulation and Testing

Two-wheeled vehicles, such as motorcycles and bicycles, tend to lateral instability of their characteristic modes (weave and wobble) at certain longitudinal speeds. These instabilities may pose a critical safety risk for (bicycle and) motorcycle riders.

Weave is a low-frequency oscillation (up to 4 Hz) of the entire motorcycle (or bicycle) and tends to be unstable at low and (potentially) high speeds. Wobble is a higher frequency oscillation (4 to 10 Hz) of the front assembly around the steering axis and may occur when riding hands-free at intermediate speed at motorcycles (or even hands-on at racing bicycles).

The aim of the project is to derive

• guidelines for the design, testing and evaluation to enhance the stability behaviour of motorcycles without sacrificing the handling and agility properties of the motorcycle
• to implement and compare different passive and new (semi-)active measures/devices  

Figure 1: Measured steering angle oscillations and limit cycle at initiated wobble mode of a motorcycle

References

Edelmann, J., Haudum, M., & Plöchl, M. (2015). Coordination of guidance and stabilization tasks for bicycle rider modelling, opens an external URL in a new window. Proceedings in Applied Mathematics and Mechanics, 15(1), 627–628.

Klinger, F., Nusime, J., Edelmann, J., & Plöchl, M. (2014). Wobble of a racing bicycle with a rider hands on and hands off the handlebar, opens an external URL in a new window. Vehicle System Dynamics, 52, 51–68.

Plöchl, M., Edelmann, J., Angrosch, B., & Ott, C. (2012). On the wobble mode of a bicycle, opens an external URL in a new window. Vehicle System Dynamics, 50(3), 415–429.

Klinger, F., Nusime, J., Edelmann, J., Magnani, G., & Plöchl, M. (2013). Wobble of a bicycle with rider hands-on and hands-off, opens an external URL in a new window. In 23rd International Symposium on Dynamics of Vehicles on Roads and Tracks (p. 7).

Researchers

• Christoph Ott
• Agnes Poks

Project Funding

Industrial