Shifting level behind wheel

[N Dheeraj Chowdary]

Hi. We are planning to implement a hand-clutch paddle placed behind the steering wheel, on the driver's left side. For gear shifting, the inital idea of placing paddles was scrapped because having the clutch would lead to the creation of smaller paddles.

Instead, we are planning to place a spring-loaded lever on the right side. Pushing the lever up would shift up. After shifting, the lever comes back to its original position (similar to a motorcycle's shifting) and pushing down would mean shifting down. The lever is to be designed to rotate along with the wheel, so that it stays in the same angular position with respect to the wheel. We are using a pneumatic cylinder for shifting, so it's electronic.

Our drivers seem to like the idea, but is it any good? I would appreciate suggestions on how to set up this system and alternatives if any.

Thank you so much.

[JulianH]

Try it.

Build it from Wood or Aluminum or what ever. Give it to your drivers and ask them if the like it. If they do -> build it.

[Owen Thomas]

What you are describing sounds like a turn signal switch on a production car - is this accurate? If so, it is certainly a tried and true method of driver control, however I am not certain it will have the effect you are looking for. The driver may tend to "hover" thier hand over the shifter mid-corner instead of being able to grip the wheel, and it might not be very easy to shift mid-corner either. Although, (and I have often thought about this) for driver training purposes it is probably a good idea to have a system which is difficult to shift in the middle of a turn, so the driver is forced to quickly learn to be in the right gear. Trade off between expecting high performance from the driver and allowing for them to correct mistakes, I guess.

I would also back up Julians opinion. For ergo stuff, it always seems best to just mock something up and have your people sit in the chassis with it. Don't forget that they MUST make wicked racecar noises with thier mouth while pretend driving - otherwise it does not count and thier opinion becomes invalid.

[Dunk Mckay]

What are you using for you clutch? Is that also electronic control? We've used a servo clutch in the past and kept two shifter paddles, one on each side (although they are physically connected so pushing one does the same as pulling the other, just for those one handed drivers out there). But we then had a small level for the clutch below the "up" shifter (right hand), which actuated the clutch, this worked really well, the fact that you're sat but a few inches in front of the engine means you can still feel the clutch biting if even if not through your hand. This is of course for clutchless shifts so was only used for starting and stopping, not sure how practical it would be for clutched shifting.

As for having a lever that you have to push down or up to shift, I'm not sure how quickly you'll be able to shift, quite important when braking for a hairpin at the end of a straight. Fingers don't bend that way so you'll have to mostly let go of the wheel to slide/wiggle your hand up and down to hit it (as with side signals), and because you'll be turning the wheel in the same direction you'll need to have it travel fairly far to stop you accidentally knocking it up or down when you turn which means even more awkward hand movement and releasing of the wheel required and slow shift times along with non-firm grip on the wheel. On top of all that I don't think it will be very intuitive for your drivers, with limited driver training hours I'd try to make things as simple for them as possible, don't want them clambering around desperately trying to shift during in endurance because they've accidentally shifted up twice while entering a tight left hander.

Will it work? Mechanically, yes. Will it work well? Ergonomically, in my opinion, no. But that is up to you and your drivers to decide. As Julian said, build a mock-up and test it.

[JulianH]

Originally posted by Owen Thomas:
Don't forget that they MUST make wicked racecar noises with thier mouth while pretend driving - otherwise it does not count and thier opinion becomes invalid.

That is brilliant, Ergonomics can be fun http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Owen Thomas]

That is brilliant, Ergonomics can be fun
And fun can be productive! Not only is it super awesome to pretend you're a racecar, it also provides a valuable distraction. While driving there are more than enough things to keep your mind busy. People have different postures and tendencies when under pressure or when multitasking, so having someone sit down with no distractions and focus on how they hold the steering wheel isn't really a good approximation. It just feels funny focusing on a specific piece of ergonomics or driving without all the other stuff happening anyways, so at the very least I like to try to strike up a conversation or have music or make engine noises.

[Racer-X]

See if your drivers like it.

If it is like a turn signal, which it sounds like, I personally wouldn't like it. I feel like I would be hitting it if I was driving, I do that all the time with my turn signal I actually broke one that way... Then again I have to hand over hand in a car.

You could put it on the column just to say you have column shift, maybe even make it an H pattern like a 3 on the tree.

[Matthew Newman]

We normally run a column sequential shifter to the left of the driver, approximately in line with the driver's hip. We sift up by pushing it forward, and shift down by pulling the shifter back. The clutch handle in mounted to the front of the shifter column. This allows the driver the grab the clutch and pull the entire assembly back to change down. We continue to run with the design most years since it is very simple to design and build, and it seems to work for majority of our drivers from an ergo point of view.

[N Dheeraj Chowdary]

Owen: Yes, it is similar to a turn signal. I will keep your inputs in mind.

Dunk: I was thinking the same thing. Even if the accidental shifting doesn't happen during a tight left hander, shifting down would require an clockwise movement of the fingers while the steering wheel is being rotated anti-clockwise. This might be counter-intuitive and confusing, because both are rotary motions. Am I correct?

Matthew: That is what we went with last year with a four-bar mechanism, but we want more hand-on-wheel time, so we have moved away from the column sequential shifter.