Going Downhill Faster with SolidWorks: The Bo-Dyn Bobsled Project’s “Night Train 2” (Part 2)


Image Courtesy of Bo-Dyn Bobsled Project Inc.
Image Courtesy of Bo-Dyn Bobsled Project Inc.

In yesterday’s post I discussed the challenge the Bo-Dyn team faced when they started building a new bobsled for the 2014 games in Sochi. Today, I’ll talk about the actual design process.

Designing a Better Bobsled

The Bo-Dyn Bobsled Project team was facing a dilemma – they needed to design a better sled, for a different mission, in less time and for less money. They had already decided on their strategy, which focused on:

1. Staying with the basic aerodynamic shape of the original, gold medal-winning Night Train

2. Improve the steering

3. Improve the chassis and provide optimized weight distribution for best handling

To accomplish these goals, the team decided to use SolidWorks.


SolidWorks – The Secret Weapon

On the original Night Train, engineer Bob Cuneo mainly used 2D design tools. This time around he was advised by team member Hans Debot to try SolidWorks. Jim Garde, the team’s chassis fabricator, also got up to speed quickly on SolidWorks with support from ModernTech, the local SolidWorks reseller in his area. The advantages became evident very quickly:

  • Better collaboration between the team members
  • Faster design and better visualization of all geometry in the design
  • Ability to manufacture directly from the 3D models
  • Eliminated interferences and collisions
  • Better control over the tolerances and aerodynamic geometry of the sled
  • Ability to see center of mass real-time and play with sled weight distribution
  • Ability to make changes and optimize chassis and steering geometry quickly in 3D
Image Courtesy of Bo-Dyn Bobsled Project Inc.
Image Courtesy of Bo-Dyn Bobsled Project Inc.


How They Designed and Built the Night Train 2

The original Night Train aerodynamics had been optimized over the last four years, so the team decided to start with this as the base shape for their design. They were able to reverse engineer the sled shape from the original Night Train using 3D laser scanning, and then use that data to reconstruct (and even tweak) the shape for Night Train 2.

Hans Debot, an expert in carbon fiber design and manufacturing, used this basic shape to flesh out a new carbon fiber body shell and the molds needed to manufacture the shell. Bob and Jim focused their efforts mainly on the chassis, steering and weight distribution. Even though the three designers were in different locations, they were able to share the design so that any changes made to the shell or the chassis were instantly available to all team members.

Using functions in SolidWorks like center-of-mass calculation and visualization, the team was able to tweak the design to balance the sled weight exactly where they wanted it. They were also able to optimize the steering mechanism, eliminate collisions, and test different design scenarios in SolidWorks, saving them time and money by not having to build physical prototypes. All of the components, including the molds for the sled, could be CNC machined directly from the SolidWorks 3D models, thereby ensuring 100% accuracy between the machined parts and the designed parts.

The Initial Tests and the Crash!

Night Train 2 performed perfectly right out of the box, requiring very few tweaks or even steering alignments–even in the first test runs.  Amazingly, the four-man bobsled team of Steve Holcomb (driver), Chris Fogt, Steve Langton and Curtis Tomasevicz turned in significantly faster times in Night Train 2 than the original Night Train, and that was without any practice or tuning required.

After winning their first three World Cup races of the season, the Night Train 2 suffered a serious crash in Winterberg, Germany.  No team members were seriously hurt, but the sled was significantly damaged. Normally this would have kept the team from competing for a few weeks while the sled was sent home for repairs to the carbon fiber body–usually requiring re-molding.

But even with a crash, the team found success success–the design and manufacturing team that is!  Jim, who had been traveling with the team as an all-around mechanic and tuner, assessed the damaged area of the sled and was able to communicate the problems caused by the crash through SolidWorks 3D CAD models and digital photos. Hans was able to design and mold a repair section in SolidWorks, complete with work instructions and repair templates to clean up the damaged area. The turn-around on the repair–which included shipping the repair kit to Germany–was a bit over two days. The team was back on the track.

The 4-Man Bobsled World Cup Season Results

Steve Holcomb, his crew and the Night Train 2 ended up winning 4 of the 8 World Cup races this year and finished in 2nd place for the 2013-2014 World Cup season – amazing considering the major crash they suffered in Winterberg. The final race in Konigsee, Germany resulted in a win, giving the team momentum toward the games in Sochi.

On to Sochi

You can watch the US Four-Man Bobsled Team and the Night Train 2 make a run for the gold on Saturday February 22nd (heats 1 and 2) and Sunday, February 23rd (heats 3 and 4).

bobsledsnippetLearn more about what goes into building Team USA’s bobsled on our website, where you can see the Bo-Dyn team present on stage at SolidWorks World 2014, as well as download our new infographic on bobsled design.

Want to see how SolidWorks can help you win new business and get to market faster? Request an in-person SolidWorks demo today.

Craig Therrien

Craig Therrien

Craig Therrien is a 3DEXPERIENCE WORKS Senior Portfolio Manager with over 30 years of CAD and industry experience - engineer, consultant, CAD product manager, CAD company co-founder. Currently, serving as Senior Product Manager for SOLIDWORKS and 3D Mold Creator. Craig has a B.S.M.E. from WPI and is a Graduate of General Electric's Manufacturing Development Program.