Abstract
In this study, evaluation method of joint torques during cycling were investigated. Newly designed cleat-sized biaxial load cells and an analytical system using a link model and a free body diagram of the lower limbs were developed. The biaxial load cells, which are made with stainless steel, were attached to the bottom of cycling shoes in place of plastic cleats. Any cyclists were able to use their own bicycle, cycling shoes and bicycle pedals with the load cells which were almost same size to plastic cleats (Shimano Corp). The load cells measure the magnitude and direction of right and left pedal force using a total of 16 strain gauges (8 gauges for vertical load and 8 gauges for horizontal load) in each load cell. This analytical system uses the link model of human limbs to identify the positions and angles of each segment of the lower limbs. The free body diagram of the lower limbs consists of 3 segments: thigh, shank and foot. The positions of each lower limb segment, joint torques and forces can be calculated using this system. Here, the relationship between ankle angle and crank angle were analyzed with this system using image-analysis software (TEMA 3D) with a high-speed camera (Photron FASTCAM SA4). This cycling power analysis and optimization system was applied to beginner and well-trained cyclists to investigate the applicability of our system.
