Author: Pascal Arnold

Sponsors: Sika & ETH Zurich Foundation, sia Abrasives, Indrohag, Georg Kaufmann, Quadrant, Bucher, AUDI, Promec Estech, Ruag, V-Zug, Franz Marty, and Swiss Bobsleigh and Skeleton Federation (SBSV)

The joint project CITIUS (latin for "faster") aims to design and produce very fast bobsleds (2-Man and 4-Man) for the Olympic Wintergames in Vancouver 2010. Research is done in the fields of aerodynamics, steel-to-ice friction (design of sliders), damping materials between chassis and cowling and bodywork manufacturing by several institutes at the ETH Zurich, whereas our work at the Center of Mechanics is concerned with the kinematics of the chassis and suspension.

                         The Citius 2-Man Bobsled in Action (Worldcup Cesana 2009)

Measurements of relevant degrees of freedom of the multibody system “bobsled” as well as detailed mechanical studies of state-of-the-art sleds are carried out to understand the characteristics of a bobsleigh run and to find hints to the energy dissipating effects. Kinematic analyses of subassemblies lead to unusual solutions with enhanced adjustability. It is a requirement to handle a large span of different track traits and weather conditions as they have a substantial effect on the performance, so a detailed knowledge of the possibilities of the chassis setup is needed.

These ideas have been realised in six 2-Man and three 4-Man sleds that are currently used on the 2009/2010 bobsleigh world cup tour.

                           Measurements of Swivel Joints during a Bobsleigh Run