There are trundle wheels whose drive wheels have circumferences of exactly 1 metre so that a simple counter that counts each whole revolution. I used one in my teaching. The wheel simply had a small "clicker" that clicked each time the wheel rotated once, so the counter was the "carbon-based life form" that pushed the wheel along the ground. My classes and I used it to measure distances up to 7.25 km! (That maximum value was the ditance between two towns measured along the highway.) Over the years, I wore out several of those trundle wheels and had to buy new ones from educational equipment suppliers.
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