Biomechanical evaluation of the comfort of automobile clutch pedal operation

The objective of the present study is to investigate not only the subjective comfort perception of clutch pedal operation, but also possible correlations between subjective rating and biomechanical parameters such as joint angle, moment and work for a better understanding of discomfort. The influence of four main design parameters of clutch pedal (seat height, pedal travel, pedal travel inclination, pedal resistance) was studied using a multi-adjustable experimental driving package. Fifteen subjects participated in the experiment. They were five short females, five average-height males and five tall males. Comfort was evaluated using a general comfort rating scale. The relationship between comfort rating and biomechanical parameters was explored. Globally, the results from the biornechanical evaluation of comfort/discomfort are consistent with those from the subjective evaluation. Both agree with the principle of minimum work, observed in biomechanical analysis of leg movements. This is characterized by the preference of not raising the leg during the approach phase, and the preference of low joint work at the knee and hip during the depression phase. Practical recommendations of clutch pedal design are discussed and suggested. Relevance to industry The results of the present study can aid ergonomists in understanding the discomfort caused by foot control operations as well as in the design of pedal controls. (C) 2004 Elsevier B.V. All rights reserved.