Parametric analysis of the stability of a bicycle taking into account geometrical, mass and compliance properties

Sergio Roa, Alberto Doria, Luca Taraborrelli, Valerio Favaron
2018 International Journal of Vehicle Design  
Some studies of bicycle stability have applied the Whipple Carvallo Bicycle Model (WCBM), which describes the roll and steer behaviour of a bicycle, allowing analysis of its characteristics of stability and in particular self-stability. One of the limitations of this model is that all structural elements are assumed to be rigid bodies. In this paper, the WCBM is extended to include the effect of front assembly lateral compliance, and analysis focuses on study of the open loop stability of a
more » ... stability of a benchmark bicycle. Experimental tests to identify fork and wheel properties are presented and discussed. Stability analysis is carried out by a MATLAB numerical code, and specific stability indexes are calculated from plots of eigenvalues against speed. In order to rank the influence of design parameters on stability, numerical calculations are carried out in a full factorial experiment with two levels of eight design parameters. The results show that introducing front assembly compliance generates a wobble mode, but this has little effect on the range of selfstability. The forward displacement of the centre of mass of the rear frame and the increment in trail lead to large increments in the self-stability range, whereas increments in front wheel radius and wheelbase cause reduced stability.
doi:10.1504/ijvd.2018.10011996 fatcat:o34t42g2srdazgc4qk23nqz5rq