Help on coeffs of friction

[olionel]

OK, not sure if Ive posted it on the right bit of the forum but here it goes,

as part of my 2nd year project, I need to build a robot buggy that detects walls and goes up a ramp bla bla bla... well the course that the buggy will run on is wood, but painted with some greyish woodpaint, then my tryes are rubber, and I need the coefficient of friction between rubber and wood to do my gearbox ratio calculations, and canne find it anywwhere, all I could find was standard stuff like wood on wood, wood on metal, tyre on tarmac etc... Can I calculate an estimate if I find say, wood on metal and metal on rubber and go from there, relate them somehow.. Im not sure.. probably need to be posting this on a robotics forum or summit... argh.. im confused....
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1989 CG125 - Childhood Sweetheart (she got kidnapped by baddies)
1998 ZXR400 - Teenage Love (lasted three years, then she turned lesbian and left me)
2001 XRV750 - Wife Material (still getting to know her but head over heels in love)

[colin1]

not all wood is the same, not all rubber is the same

find coefficient of friction by experiment

fix wheels, and put on a slope and find at what angle they slip, from this you can find the coefficient of friction
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colin1 is officially faster than god

[olionel]

yep, I think Im going to have to do that gets some wights and a force gauge, might only measure it for the static coeeficient as that wil be the worst case scenario, going up the slope from halt. Cheers
____________________
1989 CG125 - Childhood Sweetheart (she got kidnapped by baddies)
1998 ZXR400 - Teenage Love (lasted three years, then she turned lesbian and left me)
2001 XRV750 - Wife Material (still getting to know her but head over heels in love)

[Suzuki]

If you measure the force required to break static friction (the point when it starts sliding) that peak is static friction.

Next pull the thing along at a constant speed and record what force is required, and there you have your sliding friction.



BTW, coef. of friction = kinetic friction / normal force.

ie, divide the force required to pull the block at a constant speed by the force exerted upon the block by gravity.

For static friction, divide the max force you recorded just before it started sliding by it's normal force.

Easy.
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Ride: 1999 Suzuki GSXR600 (yellow/black) IRC: Stats - Relationship Map

[lllN30lll]

let me be the first person to say
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Turbo R1
CRF450R

[olionel]

[Ork12]

F = "Mu" x R
Where f = force, mu = friction coefficient and R = reaction force (mg==mass x gravity)

[ncrn]

[Ork12]

Yeah, it rocks, or are you saying its completly wrong as its a very simplified formula which assumes everything is in a "perfect world"?
Alex

[ncrn]

[Ork12]

LOL, yeah, a smooth plane may be a slight problem when trying to accelerate, unless it was a jetbike of some description
Alex

[olionel]

Hello again... well I dunno if anyones interested at all but done all the work and finally built the thing, I thing we spent more time writing reports rather than building it.. heres a quick clip from the test track... the buggy is autonomous and totally self navigaty..woohoop

sorry for the shit quality video..

https://i4.photobucket.com/albums/y113/mr-scientist/th_MOV00002.jpg
____________________
1989 CG125 - Childhood Sweetheart (she got kidnapped by baddies)
1998 ZXR400 - Teenage Love (lasted three years, then she turned lesbian and left me)
2001 XRV750 - Wife Material (still getting to know her but head over heels in love)

[ncrn]

Now thats cool, I'm doing a robotics course next year (hopefully) so I guess I'm going to get to do similar things
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Past: 55 Sym Jet, 91 ZZR250, 03 NSR125R. Present: 97 ER-5.
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