Proximity sensor? (NOT contact sensor or arrival sensor)

I can be absent-minded about taking the trash to the curb the night before garbage day, so I thought ST might be able to help.

What I’m thinking is some kind of proximity sensor that can detect when Thing A (garbage can) is a certain distance from Thing B (Mailbox post - the curb, basically).

A contact sensor would be too close, as making sure the garbage can touches the mailbox in the right spot seems finicky. An “arrival” or “presence” sensor would be too far, since the garbage would have to move about a block away to register any difference.

Are there any devices that just measure proximity/distance, such that I can tell when the garbage can is a few feet from the curb/mailbox and when it’s a few yards from the curb/mailbox?


There are lots of these. Most of them are Bluetooth. They are the same as the devices that remind you if you leave your keys behind. IBeacons can also work well.

In order to get one that works with SmartThings, you almost always have to go through IFTTT through their maker channel. But setting up the rule can be a little complicated to keep from getting a continual or repeated reminders.

However, before getting into all that, a far easier way is to use a contact sensor or a pressure mat, but use it at the usual place for the trashcan, not at the curb. The place that you take the can from when you take it out to the curb.

Then you just need a onetime rule to check at a specific time to see if the can is still parked at the usual place. :sunglasses:

Forgot to mention I also like putting the sensor at the parking place because then you don’t have to worry about the sensor getting damaged by the trash company. At worst, you use a magnet piece on the can which is easily replaced. Or if you use a pressure mat at the parking spot, you don’t have to add anything to the can at all, and you don’t have to worry about orienting the can perfectly when you bring it back. :sunglasses: