We are not measuring it directly.
4 Newtons is something like 450 grams of force (or am I wrong yet again?), about a pound.
We have a plunger-type limit switch that requires about 4 N to push it closed, and it does that and more. And just looking at it, it gives a nice thunk when hitting the top plate.
The minibot is moving at roughly 1 meter per second, and weighs maybe 2 kg (probably more), the force to stop it in a few centimeters (I assume the plate moves at competition) is well above 4 N just from an inertia point of view.
Back-of-the-envelope:
F=ma, m=2kg, a=((1m/s)/0.1s)=10m/s^2 (I assume 0.1 sec to stop)
20 kg-m/sec^2 (
= 20 N).
If it stops faster, force goes up.
Or do I fail Physics yet again??
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