Abstract
The objective of this study was to identify the dynamic response of the bicycle rider’s body during translational perturbations, in an effort to improve two-wheeler safety and comfort. A bicycle mock-up was equipped with sensors measuring three-dimensional seat and trunk accelerations and rider’s force responses at the seat, handlebars, and footpegs. The bicycle mock-up was driven by a hexapod motion platform that generated random noise perturbations in the range of 0–10 Hz. Twenty-four healthy male adults participated in this study. Responses are represented as frequency response functions capturing three-dimensional force interactions of the rider’s body at the seat, handlebars and footpegs in terms of apparent mass, and rider’s trunk motion (one-dimensional) as function of seat motion as seat-to-sternum transmissibility. Results showed that the vertical and longitudinal apparent mass for most of the bicycle interfaces followed the resonance of the seat-to-sternum transmissibility. A twice as high magnitude was observed at the resonance, although a more heavily damped system was apparent in the seat-to-sternum transmissibility. Resonant frequencies were considerably higher in the vertical direction compared to the longitudinal direction. Different dynamics were observed for the lateral measurements, where all magnitudes decreased after the base frequency, and no resonance was observed.
Highlights
In cycling, the rider’s mass is much larger than the vehicle mass
The aim of this study is to identify the dynamic response of the rider’s body at all interfaces and in all three translational directions
There were no differences between the groups in the sternum transmissibility (STST) and apparent mass (APMS)
Summary
The rider’s mass is much larger than the vehicle mass. the rider can contribute considerably to the dynamic behavior of the bicycle, by means of voluntary control actions and by means of the passive biomechanics of his or her body. The rider’s body consists of inertial and visco-elastic properties that interact with the bicycle and affect the dynamic response of the combined system. A biomechanical model with human-like properties needs to be included to study the dynamic behavior of the combined bicyclerider system. The biodynamic response of seated subjects exposed to whole-body vibration (WBV) has been extensively reported in terms of the apparent mass (APMS). Rakheja et al.[5] and Toward and Griffin[6] measured the APMS of seated humans under automotive postures hands-in-lap (e.g. passengers) and hands-on-steering wheel (e.g. drivers) in the vertical direction. Toward and Griffin[7] measured the vertical APMS of seated humans for four different backrest conditions. A simple two-mass-lumped model was adopted to BioMechanical Engineering, Delft University of Technology, Delft, The Netherlands
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
