A laboratory technique to compare road bike dynamic comfort

Abstract

Comfort is an important characteristic in road bikes, and a major source of discomfort is the vibration transmitted to the cyclist. Since human memory tends to forget the perceived vibration stimulus strength soon after the perception is no longer present, a comparison between two situations must be done rapidly. Laboratory testing is therefore frequently used to investigate and document perception. This paper presents a laboratory technique enabling us to subject the cyclist to various types of bike vibration stimuli. The technique is based on the use of a bicycle simulator that generates vertical displacement under both wheels of a bike. A commercial bicycle is used to replicate vibration outputs at the saddle and the stem of different bikes. The strategy to determine the appropriate driving signals of each simulator actuator is presented in this paper. This requires solving an inverse problem. The results indicate that the measured and the reproduced PSD spectrum shapes are very similar. The main factor influencing the quality of reproduction is cyclist intervariability. © The Society for Experimental Mechanics, Inc. 2013.