Electric Racecar!

[Hondahero10]

Fellow NSX fans,

I am the Technical director and Lead Designer for the Drivetrain on the Western Washington University Formula SAE team. Formula SAE is an intercollegiate competition for students to work together to design, build, and race a formula style racing car. This is a great way for engineering, business, computer science, and other students to obtain real world experience. My school has a very rich history of innovation in the FSAE series. To name a few, we are well known for our in house machined 556cc V8 motor with a composite transaxle, we were the first team to use 4 wheel steering, and one of the first teams to use a composite chassis.


This year my team is trying to fund an electric race car in addition to an internal combustion car which will be powered by a CBR600 power-plant. These cars will be using the same carbon fiber composite chassis with a rear steel subframe along with a pushrod suspension. In order to make this happen we need as much funding as we can get! Please check out the link below to learn more about our racing team and what we do. Any bit of help is much appreciated and will go a long way. Thanks everyone!

https://www.microryza.com/projects/formula-electric-powertrain-research

 

[syam]

Best of luck from a fellow ex-FSAE-er

 

[Hondahero10]

Thanks! From reading your signature it looks like you own one of the cars you worked on?? What school did you go to?

 

[syam]

I went to The Cooper Union. Small school, small and new team. We formed the team sometime in 2006, and I was on the team for the 2007 and 2008 builds. I have the 2008 car now, with the smaller passanger compartment design before they made everything huge. Simple car really, tube frame, composite body, minimal electronics.

I worked on pretty much everything, team management, sponsorship, project planning, machining, intake/exhaust/engine deisgn, chassis design, suspension design, ergonomics and electronics design, cut and welded 95% of everything, made the plugs for the bodywork...Was a very fun 2-3 years of non-stop work.

 

[docjohn]

I went to The Cooper Union. Small school, small and new team. We formed the team sometime in 2006, and I was on the team for the 2007 and 2008 builds. I have the 2008 car now, with the smaller passanger compartment design before they made everything huge. Simple car really, tube frame, composite body, minimal electronics.

I worked on pretty much everything, team management, sponsorship, project planning, machining, intake/exhaust/engine deisgn, chassis design, suspension design, ergonomics and electronics design, cut and welded 95% of everything, made the plugs for the bodywork...Was a very fun 2-3 years of non-stop work.

interresting your car is a pullrod susp......In layterms can you tell us why Ferrari went with this in F1 vs the typical pushrod that every other team uses?

 

[syam]

interresting your car is a pullrod susp......In layterms can you tell us why Ferrari went with this in F1 vs the typical pushrod that every other team uses?

Pullrod suspension design is a real PITA. The main reason for going with pullrods over pushrods is lowering the center of gravity, having the shocks/canisters/rocker arms/mounts all as low as possible.

The problem with going with the pullrod design over a pushrod design is geometry. To maintain correct geometry of the suspension, taking into account camber curves, bump steer/caster, etc, you have to have a very high acting pullrod point on the upper A-arm and mate that to a relatively high-ratio rocker-arm. This, then has to be matched correctly with the shock used in the suspension design, as well as matching the spring force to allow for the correct and designed suspension feedback when cornering at certain speeds (lateral accelleration).

Now add into that the fact that most F1 cars of today's designs have the drivers in a position with their legs quite a bit above the bottom of their seat (in a recliner bed-like position), packaging becomes a nightmayer. With our design, we had our knees directly over the shock/spring/rockerarm/mount area so it worked out, and we did not have to raise the floor for aero reasons, but packaging was still probably the hardest parts of the car design.

That's a brief summery of it. I believe, with a pull-rod design, you can get better camber curves from the geometry, but as to how much better, I cannot say since we were more concerned with proper design and getting the car to the finish line rather than focusing on those last couple of tenths of a second.

 

[docjohn]

thanks ,very helpful info.