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Brake pedal pressure?
novacaine - 26/8/08 at 08:36 PM

evening everyone,

just having a play around with solidworks,

how much pressure do you thing you could put on a brake pedal?

maximum pressure, as in wedge yourself against the seat and press that middle pedal as hard as you can

i remember reading in autosport that an F1 driver presses the brake pedal with 140kg of force in hockenheim,

as far as i know, no F1 driver has made a haynes roadster so no one is likley to press a pedal that hard

do you think it would be a good figure to work with as a design maximum?

the brake pedal isnt something that you really want to be borderline on its design capacity

cheers everyone

Matt


edit to correct my horrendous spelling

[Edited on 26/8/08 by novacaine]

indykid - 26/8/08 at 08:39 PM

if you have some analogue scales, sit on the floor with the scales against the wall and your foot on them. press as hard as you can and see.

tom

Paul TigerB6 - 26/8/08 at 08:42 PM

But to design one i'd be looking a lot higher than you could ever push. As you say its not the pedal you want to take a risk with. I'm sure if i was doing 70mph towards a brick wall i'd press a lot harder than 140kg!!!

novacaine - 26/8/08 at 09:02 PM

quote:
Originally posted by indykid
if you have some analogue scales, sit on the floor with the scales against the wall and your foot on them. press as hard as you can and see.

tom



ingenious, even if it did make me look a bit odd

i put 90kg with my right leg, but with the scales at a dodgy angle,

maybe i should use 150kg as a design pressure

Bigheppy - 26/8/08 at 09:17 PM

Well, when I used to go weight training I would squat 150 kg in order to keep fit light weights lots of reps,never did go to my maximum cos I was only keeping fit. Going by my user name you can appreciate I am well big 6' 3" and twenty some stone [back then 19 stone]. I once lifted the front of a mini two foot in the air, after having the bonnet fly up due to not being secured properly, in an effort to make sure the bonnet was secure. So I would think that double your weight should be a minimum for your calculations. what i'm getting at is that you can exert alot more force in a panic situation than you can in a simple experiment.
But also consider if you sell the car someone larger than you may buy it and as you designed the pedal you could be held responsible if he exerted more force than your design pressure, and it failed causing death or injury.

novacaine - 26/8/08 at 09:27 PM

I've posted the results of the solidworks FEA

HERE

Ive used 150 kg as a design force on the old pedal design (the one outlined in the book)

150kg is about the maximum that the pedal will take in its current design state, but with the alterations i have made (see post) it will take well over 450 kg with no problems

Dusty - 26/8/08 at 09:37 PM

quote:

I once lifted the front of a mini two foot in the air, after having the bonnet fly up due to not being secured properly, in an effort to make sure the bonnet was secure.

Rather than slam the car up to the bonnet to close it did you try slamming the bonnet down to the car. Or is that just for wee, non-hairy chested southern wimps.

Bigheppy - 26/8/08 at 09:50 PM

Tee Hee I slammed the bonnet down then lifted the car. I didnt realise what I had done until my passenger asked to be put down. When I tried to recreate the lift I couldn't. I could lift the back end and had much fun draging a friends mini round a corner making him think it had been stolen.

Liam - 26/8/08 at 10:14 PM

edit - oops in wrong thread

[Edited on 26/8/08 by Liam]