Short range presence detection?

I am trying to solve a problem but it is taxing my brain a bit!

My lovely neighbour comes into my house at least once a day to look after my cat while I go to work. This is absolutely fine and much appreciated - but opening the back door triggers the “Smart Home Monitor” that I have set up since it believes there is no-one home.

I have just tried putting a Smartthings Presence Sensor on the keyring but, unfortunately, she only lives over the road and it appears that her house is within the range of the sensor!

She does not own a mobile phone, and I would not want to force her to load anything on it if she did.

I was wondering if anyone else had found a solution to such a problem? I have heard of iBeacons being used - but that requires that I have a receiver somewhere(presumably) near the back door and I don’t have anything spare that I can dedicate to that task. I might be able to spare a RaspberryPi as I have two of them but that seems overkill for such an application.

So - any ideas out there for me to look at?

Any help appreciated.


Rather than trying to use presence detection, I would use a keypad at the back door. There are two that work well with SmartThings, one Zigbee and 1 zwave. The Z wave device also comes with an NFC tag that you can just touch to the keypad if you don’t want your neighbor to have to remember a code.

If your weather is severe, you may want to put the keypad inside a plastic box to shelter it.

Both these options are discussed in the following thread. ( this is a clickable link)

The zwave model runs around $59, but also includes the key tag. ( shop around, price on this one varies a lot.) Home Controls and NewEgg usually have it at a lower price than Amazon.

The zigbee model lists for around $45, but is often on sale at Lowe’s.

If it’s a normal hinges door, you could use a smart lock. Or you could get the iris key fob (assuming you’re in the USA).

Unfortunately it really needs to be something with no action required. Just walk up to the house and it detects its presence. The neighbour already has a key so does not need any other door lock.

Then you probably have to go to an iBeacon or a facial recognition camera. Or a smart lock like August with Bluetooth recognition.

If your neighbor has an iPhone, it’s pretty easy: you can put an app on her phone and just use one IBeacon at your house and her phone coming close to the Beacon can then trigger an action that will disarm your system.

The August lock works the same way and as long as you have the pro 3 model you could also use the lock unlocking to trigger other smartthings events.

Put a mult-sensor inside a can that sits by the back door, flip the can before entering the back door :slight_smile: , temporarily disable SHM, enable it when the door opens and closes again.

Ha, i was just going suggest wrapping the fob in Aluminum foil to reduce the RF range.
Just find a aesthetically pleasing way to shield the fob a bit.

1 Like

That’s a good idea. If your neighbor can remember to be consistent about it, you can just store the fob in a faraday bag And take it out when she’s on her way over to your house. That’s what a lot of Airbnb hosts do, they just tell the renter to put the keys with the key fob back in the bag when they leave.

Here’s a typical one, but there are a lot of different brands and styles under $10:

1 Like

I’m impressed with the lateral thinking there!

1 Like

Poking around in my “unfinished/unstarted projects” box, I found a pi zero and some assorted Bluetooth tags so I might have a mess round and see if I can come up with something.

1 Like

If the precence key fob is in range at your neighbors house, chances are that a cheap 8$ Xiaomi button could be in range too… Just program that to arm and disarm SHM… :grin:

I suspect BT has a wider or equivalent range as the ST presence sensors. In my experience at least.

The point about using Bluetooth devices, and specifically Ibeacons, is that you can “range” them, so that you choose to act on the signal only at a certain level of signal strength. The ibeacon specification defined these as “immediate” (just a few centimeters), “near” ( up to about 3 meters) and “far” (around 12 to 15 m depending on local conditions).

I have mine set to detect in the “near” range, which is much smaller than a SmartThings presence fob. :sunglasses: