Make a non-powered road tube senor

I was wondering if anyone has a idea where I can put a rubber hose (small) in my garage and somehow without power, have the pressure change trip a magnetic reed switch, or more simply, close or open a contact on the pressure change of a tire rolling over it. Thanks

Perhaps if the hose is sealed at one end and filled with water.
Then have the other end open but “up high” and have a fairly tight fit magnet in there between where the tire rolls over and the open end.

In theory the magnet should move about as much as the width of the tire.

But that is what I can think of with what you want.
But that is of course not a sure method.
I would probably try and go for something else.

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Excellent. I can take the magnet that comes in a Wyze reed switch, shave down a wine cork and hollow it out, shove the magnet in, then mount the hose upon the wall, have the 433Mhz receiver further up the hose and when the cork reaches it, the switch communicates to HA. I realize it this requires power, but I have many of these Wyze button battery sensors. Very nice thanks. I gave up on trying to detect when my iphone leaves the house. In a quiet state, it can not respond to an arp/udp ping for 19 minutes before it wakes up. I like this analog (initially) method.

I recently started looking in to LoRa devices.
Have one in the car with a battery charged while the car is on, and a receiver in house.
Because the long range you can even do stuff prior to arriving home and use the rissi signal to see how far out.

But it’s yet untested, and just in my sketchbook in my head.

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How about something like this https://shop.pimoroni.com/products/adafruit-mprls-ported-pressure-sensor-breakout-0-to-25-psi ? There are many more variants out there.

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I like this idea better than mine.