Dynamic modeling, simulation and experimental investigation on cycling-trainers equipped with suspensions considering human biomechanical characteristics

Abstract

At present, to meet the innervation and the comfort of cycling-trainers, the trend of deploying suspension system is still upwards. However, there is no reliable dynamic model for cycling-trainers equipped with suspension systems, and the influence of the suspension damping on the dynamic responses needs to be explored. In this paper, based on a commercially available cycling-trainer with suspension systems, a non-linear dynamic model of trainer-human coupled system was established. According to the bench test, the damping coefficient of suspension dampers was measured. By the cycling test, the dynamic model was validated. The test values of the vertical acceleration of the human lower trunk are in agreement with the simulation values, in which the maximum deviation is less than 15.0 % and the root mean square deviation is less than 8.0 %. Based on the model, the influences of the damper damping on the dynamic responses were analyzed. The results show that the influence laws of the suspension damping characteristics on the human body responses vary greatly under the different riding frequencies, and an optimal damping exists to avoid excessive fatigue caused by vibration under the medium and low frequency riding conditions. The established model and the revealed rules can provide useful reference for the suspension design and optimization of cycling-trainers.