this post was submitted on 28 Apr 2024
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What is this thing?
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I don't know for sure, but I think theoretically you could calculate the time it takes between a tire driving over each line to determine the vehicle speed. I imagine that's why there are two lines and not just one.
For sure can do speed if you know how far apart the lines are.
Probably work if distance between front and rear axle was a standardised measurement, but since it isn’t this wouldn’t be very inaccurate.
For counting or for speed? You can't really measure speed with one because of that issue, but you easily can with two. For counting it's probably good enough to count pulses and divide by two. Sure, some trucks have more than one axle, but it might not matter. Plus I'm guessing with enough data they have a signature of what multi-axle vehicles look like.