solenoid shifter

[Richard Lewis]

We're going with a seperately actuated foot clutch with our pneumatic shifting. We were considering clutch by wire, but are not entirely convinced of its advantages. Also, launch control to use a clutch by wire system scares me a bit after watching F1 struggle so badly with it last year. I'm sure it can be done, and has been done... the question is if the gains are worth the costs.

-------------------------
UVIC Formula SAE Team

http://fsae.uvic.ca

[Dan B]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Andres:
Are everyone using a clutching system that is operated manually, or anyone has incorporated the clutch to the electric actuator, or anything similar?? any thoughts on this??<HR></BLOCKQUOTE>

We use a pneumatic cylinder for the clutch to down shift as well as the up/down shift cylinder. We also use a hand clutch for starting and stopping.

[Duke of URL]

Clutch by wire is one of those things that requires a few years to develop properly.

Ideally, it would be developed using a previous vehicle to test it on.

Once that's done to everyone's satisfaction, then it can be grafted onto the current car.

Problem is, everyone wants to work on the new car (at least here anyways).

Also need to make sure that the previous car is left intact to play with.


As for the clutch, we are also using a manual clutch. Mostly to shorten the development time (we're very impatient).


One thought about the clutch by wire is to use an analog clutch control.

In that, the there would still be a clutch pedal, but it would send a proportional control signal to some kind of actuator on the clutch.

All that does is simplify the clutch cable routing. Simple is good.

DC

[EliseS2]

We ran a soleniod shifting mechanism on a previous year car. It was heavy and drained power from the engine. With our new rear end we do not have room of a large soleniod. Our pneumatic system seems to working alot better.

[Duke of URL]

I can't quite figure out why people keep using solenoids if they have so many problems.
Everybody that I've talked to complains about weight for the power you get.
Leave solenoids for power door locks.

Pneumatics and hydraulics are good, but full electronic motion control is better. Servos are the way to go.

DC

[Travis R]

This is the same thing I posted in the other thread.
We used a kliktronic with our f4i in 2002. I like it, but finding neutral was a little tricky at first. It's become a lot easier as the tranny got broken in (sloppy) and we got better with the buttons.
The other problem is grabbing neutral on your way to second. But if you hold the button down just a hair longer it isn't a problem. Our ECU will do ignition cut for shifting, but I like it better turned off. But that's just me.
We're also looking into servo actuation.

Travis Rouse - Test Pilot - The University of Texas (Austin)

[Christopher Chow]

Ok, this may seem off topic but...
My Mini-Baja team uses a manual trany. The tranny is from a atc 200 from 1981 and has an automatic clutch. Ie. the shifter is linked to the clutch so that when you shift (up. or down) the clutch is disengaged. Heres the interesting part, Im trying to go with an "electronic" shifting system that can comply with the Baja rules, and i belive that this rules out pnumatics. So the system must be totally electronic. Where can I find servos that are powerful enought to shift and disengage a clutch? I figure is about 30 lbs of force over 1.75 inches of travel.

Thanks!

Chris

[Duke of URL]

Is the 1.75 inches travel or lever arm?
The servos that I've been looking at are spec'd in torque, not force.
What is the peak value for the torque to execute a shift?