mouse feet-coefficient of drag vs. surface area

[typo]

it would seem to me that mouse feet with less surface area,ie smaller would create less friction with the mousepad. even if they are ptfe. i have found the opposite to be ture. larger feet on a mouse glide much more smoothly and make for faster mouse movement with less effort. this seems to go against science. any one have an explanation for this?

[J888www]

No offense intended, but this seems a little too technical for a monkey. I usually just use what works and not have to waste time contemplating why it works......

[NKRO]

Perhaps because your hand is on the mouse applying pressure, and so the pressure is greater if there is a smaller area of contact with the pad?

The weight will be better distributed over the area of the mouse as well, rather than just the edge of it, and I am sure that having a larger area will also lessen the impact of dust/debris getting in the way.

I'm sure there is probably a perfect balance between having too much surface in contact with the mouse pad, and not enough contact to spread the weight/pressure out sufficiently.

[manfaux]

Perhaps because your hand is on the mouse applying pressure, and so the pressure is greater if there is a smaller area of contact with the pad?

The weight will be better distributed over the area of the mouse as well, rather than just the edge of it, and I am sure that having a larger area will also lessen the impact of dust/debris getting in the way.

I'm sure there is probably a perfect balance between having too much surface in contact with the mouse pad, and not enough contact to spread the weight/pressure out sufficiently.

that, along with the weight of the mouse itself, will result more friction on most mousepads, especially cloth ones.

If you try a aluminum pad( eg Steelseries SX) or icemat, smaller feet usually equates less friction, pretty straightforward there.

[manfaux]

Uh.  No Classical Mechanics 101 grads here?

Show Image

So next trick question.

Why are thicker tires better at giving traction if the Friction formulas do not depend on surface area of contact?

when the tires are running normally on tarmac, we are talking static friction, once the tire starts slipping, kinetic f kicks in and thats where the contact area matters.

[manfaux]

I don't see A (for Area) in either equation.

It's in the miu I believe, I could be wrong though, high school physics is a while ago

[manfaux]

bu ya going back to your tire question, snow/winter tires are really just softer to provide a bigger coef. of friction. The real reason why they are wider/thicker is because the tires still need to be strong enough to hold up given softer material.

now my physics is so rusty, I'm disappointed in myself about the fact that now I know more about cars than I do about physics. Sad sad sad

[Soarer]

It's a trick question; wider tyres don't always get better traction, it depends a lot on the surface. On warm dry tarmac they would, but that's due to differences in how they deform under load, and nothing to do with a difference in friction.

[typo]

ok, so nkro explained it. ripster gave the formula that is in use. job well done.
glad to see other people actually think about this stuff.

now, back to the discussion of tires.

[Azuremen]

Uh.  No Classical Mechanics 101 grads here?

Show Image

So next trick question.

Why are thicker tires better at giving traction if the Friction formulas do not depend on surface area of contact?

Because tires are inflated and thus not actually smooth on the bottom. This combined with cornering loads leads to different parts of the tire being in contact with the road surface. Wider tires also tend to have less sidewall to width, which reduces tire squirm.

But yeah, tires are a huge ***** as far as modeling and design go. Compound is generally the most important aspect though.

[typo]

tidbit: if you look closely at the drag car pic posted you can see the tire is actually screwed to the rim with multiple screws! you have do do this because those super soft squishy tires when you spin the sh.. out of them they will literally role off the rim!

how about a discussion of "torque and recoil"? lol.

[killy]

A more instructive way to teach him would be a thought experiment:

Imagine you had three feet on your mouse. Each was a pyramid with the point facing the mouse pad. This is the limiting case of smallest pad size. What do you think would happen?

Now imagine the entire bottom of the mouse is coated in teflon. What do you think will happen now?

[killy]

****! J'accuse!

[TheSoulhunter]

Someone should invent a frictionless mouse/pad combo,
a hover mouse, perhaps via magnetic force...

[manfaux]

Someone should invent a frictionless mouse/pad combo,
a hover mouse, perhaps via magnetic force...

try a really light mouse(salmosa pro gaming edition) on a aluminum pad

[TheSoulhunter]

try a really light mouse(salmosa pro gaming edition) on a aluminum pad

MX518/Lachesis on a glass-pad (Icemat) here!

[Arc'xer]

Someone should invent a frictionless mouse/pad combo,
a hover mouse, perhaps via magnetic force...

They should start offering more mice with ceramic feet. It might not be good for most mousepads though as the harder ceramic would wear down cloth, plastic, and metal more so over time. But at least you don't have to worry about mice feet wearing down and always have the same consistent glide as long as the ceramic is clean and not damaged. The only issue would be making ceramic feet in a proper shape(eliminate the need for a plastic lip around the feet to avoid crude traps), contour, and size to maximize usefulness; though it's hard to have a proper agreement as some like smaller mice feet and some prefer larger.

In a way similar to the consistency and lasting power of the icemat. Who's only flaw is well besides size and wearing down mice feet is breaking or getting the surface/paint scratched. I guess you can count the surface as a negative if your not a fan of smooth pads.

And as for the icemat(glass) it might cause more noise I guess though I can't find any information on anyone using a ceramic footed mouse with glass. Hard to find info as only two or three mice on the market(eSports Nova, Ozone Smog, and I think one more) use them.

[JinDesu]

They should make a mousepad that is like an ice-hockey table, and the mouse would just float on a cushion of air.

[kill will]

that is an incredible idea.  i bet it could sell for 100$ bux and would be cheap to make.

[HaiiYaa]

Thats an horrible idea. I had many mousepads and steelseries S&S was the most frictionless by far and constantly missed my target because it was too frictionless. The perfect mousepad is the one that gives you low friction but still control

[typo]

i agree. i like high quality tightly woven cloth pads. i do not know if that is best for the sensor in my g500 but it gives the right amount of resistance. so i am not sliding past where i need to be. plus i find using a cloth pad without an armrest is most comfortable for me. just cushy enough. many times you can find good cloth pads free or cheap as promo items. most promo pads are crap though. the ones with the rubber back are better than the open cell foam by far.

[Lenny_Nero]

i agree. i like high quality tightly woven cloth pads.
[...]

Could not agree more.
For years I just used the cheapo basic 3 for a quid mouse mats,
or something free off the reps.

But a while back I saw a deal for a SteelSeries mouse and mat for an ok price.
After getting them was not too impressed with the mouse (was just the same as all the other laser mice I have used from £2 up ...a waste)
but the mat was something else and have not stopped using them since.

The only problems IMO are them getting dirty and the front edge wares  under your arm, which are not big deals.

[NimbleRabit]

i agree. i like high quality tightly woven cloth pads.

Same here, cloth pads rock!  I couldn't love my Ripper XXL more , most awesome mousepad ever.