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Disclosure: non-builder here.
Under most circumstances, the static coefficient of friction between your tires and any surface is going to be less than 1 (I know it doesn't have to be, but I don't understand this well. I assume that to be over 1 it has to be adhesive in some way), so the amount of force you can actually put down before slipping should be less than the normal force (which will be your weight here; how many robots have spoilers or create more downforce in any way?), so therefore the maximum possible acceleration should be 9.83m/s^2 no matter how absurdly powerful your robot is... right? This is why there is a ceiling for road cars in 0-60 times below 3 seconds. (Bugatti Veyron 2.46 seconds, Porsche 918 Spyder 2.2 seconds, blah blah, but that's aerodynamic downforce magic again).
I was looking through the old Storm II diary though, and I found a citation of 20mph in about 1.5 meter of space. That's a rough guess I assume, but it seems a little high... though it's the sort of thing that's hard to eyeball.
20mph = 8.9408m/s top speed
accelerates to in 1.5m
therefore minimum average acceleration is:
a = v^2/(2x distance)
a = (8.94^2) / (2 x 1.5)
(8.94^2) / (3) = a = 26.64m/s^2
Implies a coefficient of traction between the tires and arena of a whopping 2.7
Where did I go wrong? Am I just nitpicking a really old guess?
Or are really sticky tires in play? Tiny spikes?
How can you get a coefficient of friction higher than 1 between your tires and the arena? What is the perfect tire for robotic combat? The motors and batteries are up to scratch, but tires hold everything back.
Under most circumstances, the static coefficient of friction between your tires and any surface is going to be less than 1 (I know it doesn't have to be, but I don't understand this well. I assume that to be over 1 it has to be adhesive in some way), so the amount of force you can actually put down before slipping should be less than the normal force (which will be your weight here; how many robots have spoilers or create more downforce in any way?), so therefore the maximum possible acceleration should be 9.83m/s^2 no matter how absurdly powerful your robot is... right? This is why there is a ceiling for road cars in 0-60 times below 3 seconds. (Bugatti Veyron 2.46 seconds, Porsche 918 Spyder 2.2 seconds, blah blah, but that's aerodynamic downforce magic again).
I was looking through the old Storm II diary though, and I found a citation of 20mph in about 1.5 meter of space. That's a rough guess I assume, but it seems a little high... though it's the sort of thing that's hard to eyeball.
20mph = 8.9408m/s top speed
accelerates to in 1.5m
therefore minimum average acceleration is:
a = v^2/(2x distance)
a = (8.94^2) / (2 x 1.5)
(8.94^2) / (3) = a = 26.64m/s^2
Implies a coefficient of traction between the tires and arena of a whopping 2.7
Where did I go wrong? Am I just nitpicking a really old guess?
Or are really sticky tires in play? Tiny spikes?How can you get a coefficient of friction higher than 1 between your tires and the arena? What is the perfect tire for robotic combat? The motors and batteries are up to scratch, but tires hold everything back.
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