Experimental Assessment of Bobsleigh Dynamics and Ice-Skate Contact Forces

Abstract

Bobsleigh is a winter sport in which teams make timed runs down narrow, twisting, banked, iced tracks in gravity-powered sleds. Up to now, the optimization of bobsleighs has been carried out on the basis of athletes feedback. This has led to small modifications of the sled without univocal guidelines. This paper presents the results of an experimental campaign carried out at Cesana Pariol Olympic track with an instrumented two man bobsleigh. Aim of the experimental campaign was to assess the bobsleigh dynamics in order to objectively evaluate its performances and to set up a numerical model suitable for structural optimization purposes. During the tests, the bobsleigh was instrumented with an inertial gyroscopic platform to measure the vehicle dynamics, one optical sensor to measure the bobsleigh speed and sideslip angle, one potentiometer to measure the steer angle imposed by the driver. Moreover in order to estimate ice-skate contact forces, dynamometric axles have been designed and used during the tests. In particular forces have been reconstructed on the basis of the deformations measured by strain gauges placed on the axles connecting the sled with the skates.