Mobile Chicken Coop Includes Wireless Sensors

January 28, 2013 by Mike Szczys 6 Comments

mobile-chicken-coop-build

In and of itself this mobile chicken coop is a pretty nice build. There are some additional features lurking inside which you don’t find on most coops. [Neuromancer2701] built-in a set of sensors which can be accessed wirelessly. It makes it a snap to check up on the comfort of the hens without leaving the couch.

At the heart of the sensor system is an Arduino along with an Xbee module. The build isn’t quite finished yet, but so far three sensors have been implemented. A thermistor is used to read the temperature inside the coop. To make sure there’s enough water, two sheets of foil tape were applied to the water reservoir. The CapSense library measures the capacitance between these plates which correlates to the water lever (we’ve seen this type of water level sensor before). And finally, there’s a sensor that can tell if the door to the coop is open or shut.

He’s having trouble automating the door itself. This can be pretty tricky, especially if you go for a super complicated locking mechanism like this one.

Vintage Kegerator

January 23, 2013 by Eric Evenchick 25 Comments

[Kerber] got his hands on a classic 1950’s General Electric fridge, and converted it into this classy vintage kegerator.

As his build log shows, it took an intensive restoration process to get this fridge back in shape. He completely stripped it down, scraping off the sixty year old insulation, fibreglass, and glue. Then the chassis was sanded down to a smooth finish and painted black. R-19 insulation was added to replace the old stuff.

Next up was electronics. An Arduino, DS18B20 temperature sensor, and a solid state relay were used to regulate the temperature and prevent frozen beer. There’s also a Guruplug server that reads data from the Arduino every minute. It makes this data accessible through a web page, so the temperature of the kegs can be monitored from anywhere. [Kerber] admits that this is overkill, but leaves room for future expansion.

The kegerator draws about 180 Watts, and runs for about 6 minutes per hour to keep the temperature regulated. This is pretty impressive considering the age of the fridge. The final restoration looks great, and serves up data along with the beer.

Replacement Controllers For Slot Car Racing

January 23, 2013 by Mike Szczys 11 Comments

replacement-controllers-for-slot-car-racing

That blur on the right is a car racing into the frame. But look around the rest of the image and you’ll see the area is littered with extra hardware. [Matthew], [Doug], and [Barry] have been hard at work adding extra functionality and replacing the original controllers on this Scalextric slot car setup. So far it looks like their build log has not caught up with all the work they’ve done. We’re hoping to learn more details as they have time to write about them (this is coursework at University so we’re sure there’s a lot on their plates). But for now there are several videos and a gallery of images to drool over.

The cars are controlled by the voltage level in the track. The team replaced the stock controllers with a Raspberry Pi. It manages that voltage using Pulse-Width Modulation via MOSFETs. This allows the races to be automated but also makes it simple for a human operator to use just about any input device imaginable to control the cars. For good measure they also added a lap counter that uses an IR LED and detector to sense when a car passes the finish line.

After viewing several of their videos we think the goal of the project is to log the fasts times without sending the cars flying off the tracks during the turns.

Brute Force Finds The Lost Password For An Electronic Safe

January 21, 2013 by Mike Szczys 24 Comments

brute-force-an-electronic-safe

[Teatree] tells a sad, sad story about the lost password for his fire safe. The electronic keypad comes with a manufacturer’s code as well as a user selected combination. Somehow he managed to lose both of them, despite storing the user manual safely and sending the passwords to himself via email. He didn’t want to destroy the safe to get it open, and turning to the manufacturer for help seemed like a cop-out. But he did manage to recover the password by brute forcing the electronic keypad.

There is built-in brute force protection, but it has one major flaw. The system works by enforcing a two-minute lockout if a password is entered incorrectly three times in a row. But you can get around this by cutting the power. [Teatree] soldered a relay to each set of keypad contacts, and another to the power line and got to work writing some code so that his Arduino could start trying every possible combination. He even coded a system to send him email updates. Just six days of constant attacking netted him the proper password.

An Arduino Hydrogen Blimp… Oh The Humanity!

January 19, 2013 by Mike Szczys 48 Comments

arduino-hydrogen-balloon

This sort of flying contraption seems more suited for indoor use. Well, except for the fire hazard presented by building an Android controlled hydrogen blimp. The problems we often see with quadcopters come into play when a motor wire comes loose and the thing goes flying off in a random direction. Loosing a motor on this airship will be no big deal by comparison.

Because the build relies on the buoyancy of the gas, light-weight components are the name of the game. The frame of the chassis is built from balsa wood. It supports two tiny DC motors which are almost indistinguishable in the image above. An Arduino nano and wireless receiver monitor commands from the transmitter and drive the propellers accordingly.

You may have noticed that we categorized this one as a chemistry hack. That’s because [Btimar] generated the hydrogen himself. He used an Erlenmeyer flask with a spout for the chemical reaction. After placing several heat sinks and other scraps of solid aluminum in the flask he poured on the lye solution. This generates the H2 but you need to keep things cool using ice to keep the reaction from getting out of control. We’re going to stick with helium filled blimps for the time being!

See this beast flying around [Btimar’s] living room in the clip after the break.

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Hacking Grandfather Clock Accuracy While It’s Still Ticking

January 15, 2013 by Mike Szczys 36 Comments

[Keith] got his hands on a few grandfather clocks. Apparently the price tag is greatly reduced if you are able to get them second-hand. The mechanical timepieces require weekly winding, which is a good thing since you’ll also need to correct the time at least that often. But this drift got [Keith] thinking about improving the accuracy of these clocks. He figured out a high-tech way to adjust the timepiece while it’s ticking.

The first thing he needed was a source of super-accurate time. He could have used a temperature compensated RTC chip, but instead went the more traditional route of using the frequency of mains power as a reference. The next part of the puzzle is to figure out how to both monitor the grandfather clock and make small tweaks to its pendulum.

The answer is magnets. By adding a magnet to the bottom of the pendulum, and adjusting the proximity of a metal plate positioned below it, he can speed up or slow down the ticking. The addition of a hall effect sensor lets the Arduino measure the rate of each swing and calculate the accuracy compared to the high voltage frequency reference.