Quote Originally Posted by NHPhil View Post
Hey fellow engineers,

Our team switched over to a PE3 ECU this year (which has been a fantastic decision at every step). However, we are pretty confused where to start with setting up traction and launch control. A couple specific questions and some open-ended ones below:
  1. What types of switches do your teams use for the TC Arm and LC Arm/Start buttons? We aren't sure if toggle or momentary are appropriate.
  2. Do you use TC and or LC in any of the FSAE events? If you're willing to share, which ones?
  3. Tips/suggestions/good resources (not necessarily PE specific) for tuning traction control tables?
  4. How much do you use these tools during test driving?
Would love any help you can provide.
Phil
1. PE3 don't have the traction control bit described in their manual, you have to email them direct for that, they know about FSAE so mention it: info@pe-ltd.com
Switches are not expensive so buy a few.
2. We have a Motec M400, and have used LC in the Acceleration event with good results after very minimal setup.
3. Some traction control setups maynot have a very big table to input. You may only have to enter 2 numbers, probably the wheel slip allowed compared to road speed.
4. We have not used this enough in testing. FSAE teams rarely have enough testing time.

With our Motec,we have a dash switch to turn it on, however probably had the laptop hooked to it everytime anyway to make sure whats happening. We have 2 input signals, rear wheel speed, front wheel speed. The Motec can be setup in 2 ways, you can compare
rear wheel speed to front wheel (road) speed and select the slip allowed.
Or you can have no wheel speed sensors and just limit the engine rpm ramp rate.

I wouldn't be scared of a bit of wheel spin. A warm racing tyre still produces forwards tractive effort even when it's slipping with the road. A guy on this forum from University of Queensland posted a really nice scatter plot of velocity or acceleration vs tyre slip.
But you can test this yourself. Just don't have it in your mind you have to limit it to zero slip.