Wireless sensor networks are nothing new to Hackaday, but [Felix]’s wireless PIR sensor node is something else entirely. Rarely do we see something so well put together that’s also so well designed for mass production.
For his sensor, [Felix] is using a Moteino, a very tiny Arduino compatible board with solder pads for an RFM12B and RFM69 radio transceivers. These very inexpensive radios – about $4 each – are able to transmit about half a kilometer at 38.4 kbps, an impressive amount of bandwidth and an exceptional range for a very inexpensive system.
The important bit on this wireless sensor, the PIR sensor, connects with three pins – power, ground, and out. When the PIR sensor sees something it transmits a code the base station where the ‘motion’ alert message is displayed.
The entire device is powered by a 9V battery and stuffed inside a beautiful acrylic case. With everything, each sensor node should cost about $15; very cheap for something that if built by a proper security system company would cost much, much more.
[Kolumkilli] loves his Keurig coffee maker, as it makes him an excellent cup of coffee, but he doesn’t like waiting for it to brew. So he set out to make it wirelessly controlled via his computer… with the press of a button, he can have his coffee ready and waiting for him when he gets up.
After carefully dismantling his Keurig, he set to locating the main buttons on the PCB, and proceeded to wire in relays in parallel to the ones he wanted to control. Throw in a Moteino and add the notification LEDs as inputs as well and now he can control and monitor almost all the coffee maker’s functions via a web browser at his desk. Now if only he could remember to put a new coffee cup in…
There’s a great writeup on the forum post, so if you want to see a more detailed build log, check it out! And if you’re looking to add even more functionality to your Keurig, why not run a waterline to it?
[Felix Rusu’s] mailbox is on the other side of the street and he’s got a pretty big front yard. This means checking for mail is not just a pop your head out of the door type of activity. This becomes especially noticeable during the winter months when he has to bundle up and trudge through the snow to see if his letter carrier has been there yet. But he’s made pointless trips a thing of the past by building a notifier that monitors the mailbox for him.
He’s using a Moteino, which is an Arduino clone of his own making. It’s tiny and features an RF module on the underside of the board which takes care of communicating with a base station inside the house. The module seen above rolls the microcontroller board up along with a 9V battery and a hall effect sensor which can tell if the mailbox door is open or closed. When the Arduino detects a change to that sensor it pushes some data back to the base station which then relays the info to a computer or Raspberry Pi in order to send him a text message. All of this is shown off in the video after the break.
Continue reading “Mailbox Notifier Texts When The Letter Carrier Arrives”