paper: MINIBOT acceleration solution

[Ether]

Here's another idea for measuring MINIBOT rolling friction.

Release the bot from the top of the pole and time (with a stopwatch) how fast it takes to fall a distance X. Do this several times and average the results, throwing away any outliers. Make sure the motor leads are open-circuit, not shorted.

Then use this formula to calculate the friction force:

f = w - 2*X*M/(t^2)


f is friction force in Newtons

w is MINIBOT weight in Newtons

M is the mass of the MINIBOT in kilograms

t is the average time in seconds

X is the distance it fell in meters

For beginning physics students:

The above formula comes directly from F=M*a, assuming constant applied force:

F = M*a

(w-f) = M*a

a = (w-f)/M

v = integral(a*dt) = a*t = (w-f)/M*t  (assuming V = 0 at start)

x = integral(v*dt) = integral(a*t*dt) = (1/2)*a*t^2 (assuming x=0 at start)

x= (1/2)*[(w-f)/M]*t^2

solve for f to get the formula