Calibration of a measurement system for the evaluation of efficiency indexes in bicycle training

Abstract

Every athlete aims to establish the best performances in his sport activities. This can be reached by means of indications to the athlete on specific parameters to check during his training and so optimizing the effectiveness of the athletic gesture. The present study is developed within a research project on the evaluation, validation and application of efficiency indexes of the athletic gesture in cycling, by means of the measurements of the effective force to the pedal carried on by an Instrumented Pedal (iPed) and displaying measurement results in real time: the final aim is to provide a feedback to the athlete, on the basis of some efficiency indexes, in order to improve the efficiency of the sport performance. The specific goal of this contribution deals with the set-up of the measurement chain and with the implementation of the system calibration. In particular, calibration was performed with known dead weights. During calibration the crosstalk effects between measurement channels have been evaluated and modeled with a cross sensitivity matrix. Accuracy on force measurement is between 3% and 5%. Also angle and power measurements underwent a calibration procedure with a relative uncertainty between 8% and 15% of the measured value. The obtained results validate the iPed and the measurement chain and open wide scenarios for the system applicability. A cycloergometer embedded with an aerodynamic brake has been used for some tests on the efficiency indexes as obtained by athletes during different training sessions. Preliminary evaluations of efficiency indices under controlled conditions are encouraging and seem to confirm the validity of the method.