A Cheap DIY Smoke Detector that Can Save Lives

2014-07-19-16.33.53 A faulty wire, a discarded burning cigarette, or a left-on curling iron can trigger sparks of fire to engulf everything nearby until all that’s left is brittle mounds of smoldering ash. Which is why smoke detectors are so important. They are life saving devices that can wake people up sleeping inside, well before the silent, but deadly carbon monoxide starts to kick in. But what happens if no one is home, and the alarm begins to blare? The place burns down into the ground without the owners knowing.

So when [Martin] purchased a battery-powered smoke detector and rigged it up to notify him exactly when the piezo siren is activated, the evolution of the automatic fire alarm continued into the realm of wireless internet-connected things.

His home automation system (a Raspberry Pi running Node-Red) links to a Funky ATTiny84-based sensor and transmits the data wirelessly, redirecting the information to his phone. SMS messages can be sent, as well as emails and pushbullet notifications. Once the piezo siren starts to sing, the system alerts him that smoke has been detected and that he should check on it as soon as possible.

The electronics fit perfectly inside the case waiting for any smoky disturbance in the room to light up. And what makes this project even better, besides the life saving capabilities and the instant push notifications, is that it was hooked up for the cheap. No need to buy a brand-new, expensive Nest protect, when all it takes it a sensor or two and a Raspberry Pi to hack the fire alarm that already sits in the house.

This video coming up after the break shows how simple it is to make. [Read more...]

Zero-Dollar AC System Looks Funny But Works Well

Basement-cooled AC

Summer is here and with summer comes hot days. You probably know that us humans get uncomfortable if the temperature rises too much. Sure, we could turn on the loud and inefficient window AC unit and try to stay mildly comfortable while the electric company pick-pockets pennies from our change purse, but what is the fun in that? [Fran] had a better idea.

He noticed that his basement was always in the upper 50°F range regardless of how hot it was outside. He wanted the cool basement air to reside upstairs in the living area. After thinking long and hard about it he decided that a box fan and two long, skinny cardboard boxes assembled together would be enough to move the required amount of air. Both the fan and boxes were kicking around the house so was no cost and no risk to try this out. [Read more...]

THP Entry: Cut Energy Consumption by 30 percent with this WiFi XBee Setup

5277901405891974757

Let’s be honest. Paying electricity bills sucks. The amount paid is always too much, and the temperatures in the building are rarely set at a comfortable level. But now, with the help of this DIY Climate Control system, power-users can finally rejoice knowing that the heating and cooling process of their home (or commercial space) can be easily controlled through the utilization of an XBee Remote Kit and a process called zoning.

The team behind the project is [Doug], [Benjamin] and [Lucas]. They hope to solve the inconsistent temperature problems, which are caused by a moving sun, by open-sourcing their work into the community.

Their XBee system runs on a mesh network making it a perfect tool for sensing and communicating which areas in the house are too hot or too cold. Once the data is collected, XBee modules route the information wirelessly to each other until it reaches a central Arduino gatekeeper; which then decides if it wants to heat, ventilate, or air condition the room.

Not to mention all the added benefits posted below:

[Read more...]

Long Range Wireless Sensors for the Home-Area-Network

7785441404784533190 In the near future, we will all reside in households that contain hundreds of little devices intertwingled together with an easily connectable and controllable network of sensors. For years, projects have been appearing all around the world, like this wireless sensor system that anyone can build.

[Eric] hopes his work will help bring the truly expansive Home-Area-Network (HAN) into fruition by letting developers build cheap, battery-powered, long-range wireless sensors. His method integrates with the pluggable OSGI architecture and home automation platform openHAB along with using an Arduino as the lower power, sensor node that is capable of utilizing many types of cheap sensors found online.

[Eric]’s tutorial depicts a few examples of the possibilities of these open-source platforms. For instance, he shows what he calls a ‘Mailbox Sentinel’ which is a battery-powered mail monitoring device that uses a Raspberry Pi to play the infamous, and ancient AOL sound bite “you’ve got mail.” It will also send an email once the postman cometh.

In addition, he lists other ideas such as a baby monitoring sentinel, a washer/dryer notification system, water leak detectors, and security implementations that blast a loud alarm if someone tries to break in. All of this potential for just around $20.

The key to making this project work, as [Eric] states, is the MQTT binding that ties together the Ardiuno and openHAB platform. This allows for simple messages to be sent over the Ethernet connection which is often found in IoT devices.

So all you developers out there go home and start thinking of what could be connected next! Because with this system, all you need is a couple of ten-spots and an internet plug, and you have yourself a strong foundation to build on top of. The rest is up to you.

This open, connected device is [Eric's] entry for The Hackaday Prize. You can see his video demo after the break. We hope this inspires you to submit your own project to the contest!

[Read more...]

Hamtramck Disneyland

Mike posing near the central part of the build... lots to see here!

With a few hours of down time I convinced [Caleb Kraft] to go to Hamtramck Disneyland with me. You’ve heard of it, right? I certainly hadn’t. I sounded like gibberish when [Chris Thompson] suggested it to us. Just a 10 minute drive away from Recycle Here! (where the Red Bull Creation is being held).

Without a street address we never would have found it. The spectacle is simply a house on a normal looking street in Hamtramck, Michigan. We were just a few doors down, creeping down the street, before we spied a flash of color between the houses. Swinging around the corner and into the alley this marvel opened up to us. The work of [Dmytro Szylak] started about twenty years ago. He built and built and built for years, a produced some backyard art that impossible to view without beaming with joy. You won’t spend much time there, but seeing for yourself is worth a few minutes side trip. For those that will never have a chance, here are the pictures I snapped.

[Read more...]

Android Doorbell Notifier

Breadboarded circuit to detect when doorbell rings

It’s always unfortunate to find a FedEx tag on your door saying you missed a delivery; especially when you were home the whole time. After having this problem a few times [Lee] decided to rig up a doorbell notifier for his Android phone.

[Lee]‘s doorbell uses a 10 VAC supply to ring a chime. To reduce modifications to the doorbell, he added an integrated rectifier and a PNP transistor. The rectifier drives the transistor when the bell rings, and pulls a line to ground.

An old Netgear router running OpenWRT senses this on a GPIO pin. Hotplugd is used to run a script when the button push is detected.

The software is discussed in a separate post. The router runs a simple UDP server written in C. The phone polls this server periodically using SL4A: a Python scripting layer for the Android platform. To put it all together, hotplugd sends a UNIX signal to the UDP server when the doorbell is pushed. Once the phone polls the server a notification will appear, and [Lee] can pick up his package without delay.

Fingerprint Scanner Both Simplifies And Complicates Opening Garage Door

Fringer Print Scanner Garage Door Opener

Opening a garage door by hand is a lot of work and a hassle, hence the advent of the garage door opener. Nowadays, some people may even say just pushing the button of a remote control requires too much effort. [nodcah] is one of those people so he came up with a fingerprint scanner that controls a pre-installed garage door opener. All kidding aside, it is a cool project that lets you into your garaage, keeps unknown people out and doesn’t require you to remember to carry a key or remote.

In the center of this project is an ATmega328 that runs a custom Arduino code. This ATmega328 is responsible for controlling a 16 character, 2 line LCD screen as well as communicate with an off the shelf fingerprint scanner from Sparkfun. The fingerprint scanner has a built in CPU, can store up to 20 fingerprints and does all its own processing of fingerprint scans. It then communicates to the ATmega328 with simple commands over serial Tx and Rx lines.

The ATmega328, LCD and fingerprint scanner are all mounted outside the garage in a 3D printed enclosure. If the wires for the internal-garage open/close button were just run straight into this outdoor module, anyone could open it up, short the wires and get into the garage. To prevent this, if the ATmega328 gets the ‘OK’ from the fingerprint scanner, then it sends a signal to an ATtiny85 that is inside the garage. If the ATtiny85 receives the correct signal, it will then actuate the garage door opener by shorting the open/close button contacts. This prevents anyone from sneaking into the garage.

[nodcah] did a great service to the community by making all of the part list, schematics, instructions and Arduino code available so anyone can easily put this project together.

[Read more...]