Python powered sprinkler system wastes no water

rain-gauge

One thing that annoyed [Jashua] to no end was hearing his automated sprinkler system kick on in the middle of the night, when it had rained earlier in the day. He wished that his sprinklers were a bit smarter, so he decided to give the system an upgrade.

Rather than pay hundreds of dollars for a more sophisticated automation system, he spent about $45 on supplies and scrounged together some items he had sitting around the house to make a rain-sensing module of his own.

The resulting project, Pysprinklers, uses Python along with a handful of components to better manage his water usage. He got his hands on a cheap rain gauge, and modified it with a game controller and a set of magnetic surface contacts. If there has been a significant amount of rain in the last 24 hours, his system will prevent the sprinklers from turning on. Additionally, if there is rain in the forecast, the sprinklers will be delayed a bit to see if rain makes its way into the area.

We’re all for saving money (and water), so we think [Jashua’s] system looks great, especially because he ended up using a handful of things he already had on hand.

DIY servo activated door lock with capacitive touch keypad

diy_servo_activated_door_lock_capacitive_touch

Since he was a kid [Giorgos Lazaridis] has always loved the idea of having an electronic door locking mechanism, and now that he has the means, he’s decided to construct one for securing the door to his apartment. He calls the project “simple and cheap”, though we’re not sure about the first part. Taking a look at his very detailed build log, you can see that he has invested quite a bit of time and effort into this impressive project.

Buying an off the shelf product was expensive and not a whole lot of fun, so [Giorgos] disassembled his door’s locking mechanism to see how he might be able to actuate the lock electronically himself. With minimal modifications to the lock, he was able to add a servo which reliably opens the it when triggered.

With the mechanical portion of the project out of the way, he spent a great deal of time working on the door’s electronic components, including the PIC-based controller and capacitive keypad. The keypad proved to be a bit of a problem, but after a few revisions he found a design that was both reliable and pleasing to the eye.

The locking mechanism works pretty well, as you can see in the video below, and [Giorgos] is quite pleased with the results.

[Read more...]

Simple household status system

The-Household-Informer

[BrianH] decided that he no longer wanted to venture outside on cold or rainy days just to check if the mail had come, so he built himself a notification system that would alert him if the postman had stopped by. Additionally, he admits to being forgetful on occasion and wanted a way to monitor whether or not he forgot to close the garage door. His Instructable details how he accomplished both of these tasks with the household monitor he built around an ATmega168. His project uses a mailbox mounted photoresistor to determine when the mailbox has been opened, and a reed switch that is triggered when the garage door has been opened. If either of these things occur, a beep is emitted from his notifier, and the appropriate status LED is lit. Simply monitoring whether the garage door has been opened is not all that helpful, so he programmed his notifier to beep persistently at 10-minute intervals if the garage has been left open for more than an hour.

His hack is pretty useful, but he does mention that there is an inordinate amount of wiring that needs to be laid, citing his driveway repaving as a great opportunity to do so.

Making Nixie tubes at home

[Aleksander Zawada] makes vacuum tubes in his home. One of the most challenging builds he has taken on is to produce a working Nixie tube. He describes the process in a PDF, covering his success and failure. It seems the hardest part is to get the tube filled with the proper gas, at the proper pressure, and firmly seal it. In the end he managed to make a tube with three digits (0, 1, and 2) that worked for about 700 hours before burning out.

[Aleksander] joins [Jeri Ellsworth] on the short list of hackers who can pull off extreme industrial manufacturing at home. Kudos.

[Thanks Duncan]

Jeri makes integrated circuits

[Jeri Ellsworth] made this silicon inverter at home, by hand. It took her two years to get the process figured out and achieve something we didn’t think was possible. The complexity of manufacture, and the wide range of tools and materials needed seem insurmountable but she did it anyway. Her home chip fab Flickr set is well commented and details her work area and part of the processing. If you’re hurting for more check out her 40 minute Metalab talk which we’ve embedded after the break.

If her name sounds familiar but you just can’t place it you may know her from The Fatman and Circuit Girl. We’ve also featured some of her hacks, such as her Pinball challenge against [Ben Heckendorn], and her giant Etch-a-Sketch.

[Read more...]

Firefox CSS hack: change navigation icons

firefox_custom_icons

Why settle for the standard home icon on your browser? If your home button brings you to hackaday.com, why not make the icon reflect that destination? This hack is quick and simple. We’ll take you through it using Firefox 3 and the default theme with standard sized icons. [Read more...]

Home injection molding

injectionmold

[Kenneth Maxon] is a wizard who only does things one way, beautifully. While out of the average hacker’s production capabilities, his injection molding machine is amazing to behold. The machine has all features a commercial model would. It heats and cools the mold, produces over a ton of pressure to inject plastic with, and ejects parts automatically to name a few.