Bontaz R&D Team and HBK solutions support French Bobsleigh for Beijin

#INNOVATION #BOBSLEIGH #PERFORMANCE #RD

BONTAZ R&D engineers, HBK solutions and the French bobsleigh teams share a single goal: Beijing Games!

The Bontaz industrial group, a leading automotive supplier based in Haute-Savoie, supports the French Ice Sports Federation (FFSG) via a French bobsleigh partnership by providing financial, technological and human support to French bobsleigh.

Bontaz R&D teams work closely with technical staff and bobsleighers to improve equipment and optimize performance during training…. With the goal of reaching Beijing!

Since 2020, Sébastien CHATEL, Development Team Leader for Bontaz has been supervising the project – design, analysis and validation of tests in real conditions – and has chosen Hottinger Bruel&Kjaer to supply the strain gauges used. Here he answers some questions!

The partnership with the French Ice Sports Federation (FFSG), which focuses on bobsleigh, was set up in 2015, at the initiative of our founder Yves Bontaz. It is a global partnership, covering financial, technical & material, media and human issues.

The skills sponsorship targeted a continuous improvement process for the bobsleigh developed by R&D engineers to optimize technical performance. For BONTAZ, whose DNA is technological innovation, this was a great opportunity to apply our industrial know-how while helping to give new impetus to French bobsleigh.

This strong commitment has resulted in:

• • • The development of a push car 2.0 aimed at measuring and analysing the performance of athletes to help them improve performance
    • Around 10 engineers from the Bontaz R&D department working part-time on the project
    • Support from the Auvergne-Rhône-Alpes region and cross-border partners, including Hottinger Bruel & Kjaer and Astrym
    • The production of a web series #EnglisseversPekin (available on YouTube in French and English) making it possible to follow the preparation for Beijing on video
    • Numerous employees being involved on an ad hoc basis within various Group entities

Initially, the aim was to supply a BONTAZ-made bobsled for the chassis, as this was a purely mechanical matter – a subject in which the BONTAZ project team has great expertise. Only the fibreglass hull was purchased. A lot of work went into dismantling an existing bob to scan all the parts and reproduce them in 3D using design software.

The Official French Teams also gave advice or ideas for improvements on different parts so that they could be integrated into the first ‘prototype’. Once the assembly of the Bobsleigh was finalised on the computer and checked to ensure that everything could be fitted together without collision, the manufacture of the parts began. Once the assembly was completed, the pilot wanted to test the bobsled on the track and give his first impressions of the bobsled he was using in competition.

Several passes were made in order to improve the behaviour of the bobsleigh(s), as it was possible to interchange some of the independent elements of the welded part. Tests were carried out on each part of the bob, such as the pads with a dedicated trolley, the design of the brake to make it more ergonomic, the tensioners that allow the rider to obtain better steering sensations…

HBK had already worked with the FFS (French Ski Federation) on the start gate handles to find the best technique to propel oneself ahead of everyone else at the beginning of the race, thus increasing the chances of success at the finish. With the bobsleigh, the logic is the same because the push corresponds to 1/3 of the final performance (in additionto the piloting and the bobsleigh) and the complexity which has to be addressed is that it is necessary to coordinate 4 pushers simultaneously with successive boarding phases.

Moreover, there are 3 different types of handles and each one has its specificity: the pilot handle which allows to follow the flexion created by the lever arm, the side handles where we play on the torsion of the axis attached to the hull and finally the 2 back handles where we come to observe a compression of the material.
Strain gauges are therefore ideal for all these measurements.

The installation of the gauges was easy because all the handle systems were designed to be removable and therefore easily deliverable, unlike the bobsleigh which measures around 3m80. Once the gauges were in position on the bobsleigh, calibration using a dynamometer was carried out in the BONTAZ premises with the support of Astrym as all the measurements were recovered by a data acquisition system developed by this company.
This operation is one of the most important if reliable and exploitable results are to be obtained. Using the Catman software, the French Teams could graphically represent the efforts experienced by each handle and correlate them with a video to improve the athletes’ technique.

In addition to the bobsleigh instrumentation, BONTAZ supplied “wheel” kits to allow training in summer on the La Plagne athletics track with equipment as close as possible to that used in competition. For example, the handles are the same as those on the bobsled used for the World Cup runs, as well as the height in relation to the track, so that the technique can be transposed from one season to another.

Before, they used a weighted cart with handles in the form of simple tubes and sitting in the cart was not possiblewere able to sit in them. Now all four athletes can board, so all the steps of the push are worked on and improved. During the preparation races, the bobsledders made several descents which were recorded via the central acquisition system and filmed while modifying the pushing techniques (horizontal or with an angle, hands clenched or spread out…). In the evening, the whole thing was analysed by the staff to see what was a plus and what absolutely had to be avoided in order not to slow down the bobsleigh during this phase of the race.