I am living in a housing complex where we have the mailbox at the entrance. So I would like get a notification when I get mail. The problem is that I have no power available, i.e it needs to run on battery… and that there are 4 mailboxes with a common lid that the mailman opens, so it hard for me to use a door sensor since this will trigger when the mailman has been there no matter which of the 4 mailboxes he filled up!
So I am thinking about using a wifi camera instead that could make a snapshot every day at 14.00 then send the image to a script that check if there is a change in pixels since yesterday and if it so then send me an email with picture attached. Is this feasible, and if so which camera to get and how to implement it?
Sure it is, what if the mailman arrives at 14:01? At least in Denmark the mailman doesn’t come that precisely, actually it is hard enough predicting if they come in the neighbourhood at all…
I see some problems.
You need to implement some algorithm to analyze images
You need to analyze images more or less constantly
You will probaply get false positives when the lid is opened
You might consider to build your own sensor, MySensor seems to work in openHAB (I am using it myself). Some inspiration might be found here:
I guess you need to find a good way to sense if something is in the mailbox. Maybe you could put ultrasonic distance sensor inside the mailbox and measure changes in distance?
i also don’t get the idea… Unless you can see, there’s mail in your Mailbox from the outside and you’d like to compare an “empty Mailbox” with a “full Mailbox”? That would be technically speaking feasible - but you have to be sure, noone from your neighbours has an issue with you filming everything.
I personally would go with a sensor in the Mailbox - depending on the Kind of Mailbox a simple reed-contact telling you the lid from your Mailbox has been opened could be enough already. Those reed-contacts don’t Need much battery (Webcams do!) and with a simple ESP8266 you can send the reed-contact state via MQTT to openHAB.
Or an Arduino with RFM69HW which would be perhaps a little more work but last way longer on battery and potentially have greater range because it can be put to sleep much more easily. I think that is what the MySenors use.
My soil moisture sensor for my DIY sprinkler system uses an ESP8266 powered by a single 18650 2400mah battery trickle charged by a diy solar panel through a TP4056. It has yet to ever run out of juice. The trick is to keep the ESP on deep sleep, not connected to WiFi and only wake it up on interrupt and send the data. Then it goes back to sleep. The ESP can be woken up using GPIO16 or an RTC.
As I said before, when the mailman arrives he opens the big lid, for all 4 mailboxes. This means that a reed switch will detect when any of me and my neighbors get mail. What might be possible is to place a ultrasonic sensor or pir sensor on the top part of my mailbox and then it detects if something obstructs the path to the bottom of my mailbox. I am just unsure if this is reliable or highly dependent on size and placement of items inside the mailbox. The other thing is that it would be nice to get an image of what inside the mailbox, lf its packages or bills…
What I have planned to do, but never found time for it, is “load cell” based solution, which I think works with every kind of mailboxes. Basically you measure weight of the “mail”.
I think your idea for a WiFi camera is brilliant and easier to implement than others might believe. I purchased a cheap ezVIS WiFi camera which runs on USB power, a small hobby solar cell and a rechargeable battery. The battery and camera are in the mailbox. It detects motion and sends an alert. I can then look at the camera through my phone or computer and with the night vision on the camera, actually see if there is anything in the box whenever I want to.
1 Like
MDAR
(Stuart Hanlon, UK importer of Velbus hardware)
11
Have you considered a “trail camera” or “nest box” type thingy? It does nothing until it senses movement, then wakes up and videos a bit. Infrared too.
No idea if you can configure to post segment or stills upon “incident”, but you would hope so.
Depends also on the type of Mailbox you use. I have one with a big lid. And on that lid I glued a motion sensor (Xiaomi Aqara Vibration Sensor => see https://www.openhab.org/addons/bindings/mihome/#supported-devices) and everytime the lid is opened, I know there’s mail in there. Vibration Sensor works for years - but you’ll need the gateway of course.
Other option would be to use window sensor (there’s plenty of them out there), which also indicate an opening of the lid.
or as MDAR suggested, you built a second floor and weigh the content…
