[RagingComputer] built this 1-wire attic cooling fan. He’s using an Ubuntu server loaded with OWFS to control everything. The 1-wire temperature sensor is interfaced using USB while a serial x10 module sends out commands to be received by another x10 module near the fan. Back in the day we had covered a linux home automation project. We also covered HVAC hacks such as the smart attic fan and a 1-Wire HVAC monitoring system.
The 1-Wire HVAC monitoring system is for residential Geothermal HVAC systems. This project utilizes the so called 1-wire temperature sensor. A single board computer handles the brunt of the work including web accessible trend data. With access to the underling temperatures, the over all system performance may be gauged. Earlier this year we covered a HVAC web enabled monitor that adds an element of control. As the industry adopts modern control architectures, we hope to see more HVAC hacks around.
The silicon hacker behind the Chumby, [bunnie huang], was browsing through the Mobile Phone Megamarket in Shenzhen, China and stumbled upon an unusual repair book. It turns out the book had the schematics to hundreds of Nokia phones. It’s hard to tell if they are legitimate, but the amount of information makes them seem so. [bunnie] claims that the book is a learning experience because it shows how some sub-circuits are implemented. Also, it can be a good reference for sourcing parts. Since Nokia buys millions of each component, the supply of parts they use are stable. There are also editions for other brands, such as Motorola and Samsung.
[Vince Briel] has created an embedded device based on the Parallax Propeller chip that acts as a serial terminal. It takes input from a standard PS/2 keyboard and outputs color VGA. It also has a second serial port to connect to a PC for debugging or programming. He is selling kits and has the schematics available. The board has a lot of hacking potential and it could easily be made into a video game or a Wikipedia browser.
[via RetroThing]
Flex sensors, like the ones used in the Nintendo Power Glove, are generally expensive and hard to find. However, [jiovine] demonstrates that they are easy enough to make from spare parts. He sandwiched a strip of plastic from ESD bags between pieces of copper foil, and wrapped the whole thing in heat shrink tubing. The sensor is able to detect bends in either direction, unlike the original power glove sensors. His version had a nominal resistance of about 20k ohms, but by choosing a different resistive layer you could create sensors that are more or less resistive.
Related: 5-cent tilt sensor
Sometimes, pets need to be trained to stay away from certain things. Over at sump.org, his cats needed to be kept out of his room. He used their natural fear of water by creating the waterwall, a motion-sensing device that sprays water. The project is incredibly simple and uses very few components. It is based around an IR intrusion detector and a windshield washer pump. Although that worked well enough, he also hooked it up to his computer via the parallel port so that he could take pictures as the cats (or people) are sprayed. Although the project is old, it shows how few components are really needed to achieve this kind of behavior.
Related: Motion detecting cat toy
[thanks todd]
[Seth King] sent in his latest hack where he used an Arduino to regulate various aspects of a greenhouse. He has sensors for soil and air temperature as well as light and moisture. He built a custom circuit that uses relays to power fans, lights, and heaters. Using timers and the sensor data, the devices can be triggered to create the perfect environment for sprouts. He hopes to make the whole thing wireless by integrating XBees, but for now he ran a USB cord to his computer.
Related: Automatic grow light
