Turning A Light Off Over The Internet

May 3, 2012 by Brian Benchoff 23 Comments

Because reaching over a few feet to turn off a switch is too much to bear for [Bruce], he connected his desk lamp to the Internet. It’s a pretty cool build that’s the perfect tutorial for connecting just about anything to the internet.

For his build, [Bruce] used an Arduino with a relay attached to an output pin. When the Arduino receives a signal on its serial port, a tiny voltage is applied to the relay, turning on the light.

This could have been done with an Arduino Ethernet, but the PHP script [Bruce] went with is a little more versatile. Whenever someone pulls up this digital light switch web page, they can turn [Bruce]’s desk lamp on and off.

For an introduction to connecting bare bones projects to the Internet, we’re really liking [Bruce]’s build. Just try no to go crazy with that link and leave the failure testing to the professionals. You can check out the demo video after the break.

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Simple Tweak Alerts You When You’ve Left Your Headlights On

April 11, 2012 by Mike Nathan 47 Comments

landrover-headlight-buzzer

[Paul McGuinness] owns a Series III Land Rover, and as the vehicle as formerly used by the British military, it’s lacking some of the modern amenities he was accustomed to. Overlooking the lack of power steering and all-around drum brakes, the one item that [Paul] really missed was a buzzer that let him know when he left the lights running.

On more than one occasion, he’s had to have “The Sarge” jump started after leaving the lights running all day. Explaining the humiliation involved with jump-starting a Land Rover with a Nissan Micra (an unfortunate excuse for a vehicle, known here in the states as the Nissan Versa) in his blog, [Paul] decided that he’d had enough – it was time to build a headlight warning buzzer.

The circuit itself is straightforward, consisting of a normally closed relay connected to his headlights and ignition, along with a buzzer. When the key is in the ignition and the lights are on, the relay is open and the buzzer is silent. However, if the lights are on and the relay is not supplied power from the ignition, it closes and sounds the alarm.

A simple fix for a frustrating problem – we like that.

Monitoring And Controlling Your Garage Door From Afar With An IP Camera

March 1, 2012 by Mike Nathan 41 Comments

remote-control-garage-door

Last year, [Mark Simonelli’s] wife asked him if he could design something that would allow her to remotely check if their garage door had been left open. [Mark] jumped at the chance to tinker with electronics and designed a system around an old TrendNet IP camera. When remotely connected to the camera using IP Cam Viewer Pro for his Android phone, [Mark] could watch the video stream and also trigger the garage door opener via a small relay circuit he built.

His remote opener worked well, but his camera unfortunately lacked any sort of IR vision/low light capabilities. Since his camera wasn’t very useful in the dark, he decided that he needed to add some way to trigger a light when remotely monitoring his garage. He figured the best way to do this would be to control a power strip-connected light using a circuit similar to the one he built to open the garage door itself.

He stopped by the hardware store and picked up a cheap power strip, disassembling it and removing the power toggle once he got home. He fitted it with a small 5v relay, which he connected to the camera’s terminal block. While he admits that it might not be the absolute safest solution, he can easily control both the light and the garage door with a simple swipe of his phone’s screen.

Continue reading to see his remote controlled power strip in action, and be sure to swing by his site to see more details about his camera-controlled garage door opener.

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Auto Power Circuit For An Arcade Machine

March 1, 2012 by Mike Szczys 31 Comments

Some of the pinball machines which [Jeri Ellsworth] has restored have ended up in the break room at her work. We’re sure her coworkers are thankful for this, but sometimes they forget to turn off the power to the machines, and letting them run constantly means more frequent servicing will be necessary. She set out to fix the situation by building a circuit that will automatically power the machines.

We think the solution adds some much needed functionality. Instead of hunting for the power switch, you can now power the machine up by hitting the left flipper, and it will automatically shut off after about five minutes of not having that flipper button pressed. For this she grabbed a 555 timer chip and built a circuit to control the relay switching the mains power.

She added a magnet and reed switch to the left flipper switch assembly to control her add-on circuit. It connects to the base of a PNP transistor which controls a resistor network and capacitor. This part of the circuit (seen to the left of the 555 in the schematic) allows the timer to be re-triggered. That is, every time you press the flipper the 555 will reset the timer. Don’t miss the demo she filmed after the break.

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Arduino Lawn Care Is Web-controlled

February 14, 2012 by Mike Szczys 8 Comments

[Joe Fernandez] is fairly new to the hardware side of the hobby, but he seems to have easily found his way on this project. He wanted to build his own web-bridge for his Toro lawn sprinkler system. He pulled it off with style and shows off the spoils of his work in the clip after the break.

He started with an Android ADK, crafting some web magic to use a REST interface and JSON packets as a communications scheme. This makes it possible to control the system from anywhere as long as you have an Internet connection. The rest of the hardware evolved as his needs became clear. The first hunk was to add an Ethernet shield so that he didn’t need to have his Android phone connected to the system for it to work. From there he needed to control the solenoid valves on the system and grabbed three relay shields from Seeed Studios for this purpose.

As you can see, all of that hardware has a home on a polyethylene cutting board. The terminal blocks at the bottom keep the connections nice and neat as they interface with the sprinkler system. We were happy to hear that the stock controller still works, this add-on doesn’t permanently alter it in any way. That’s going to be important if he ever wants to sell the home.

Still using a traditional sprinkler instead of an in-ground system? Perhaps this variable range hack is for you.

[Jamie Zawinski] Controls His Drapes From The Command Line

January 14, 2012 by Brian Benchoff 20 Comments

As one of the founders of Netscape and the Mozilla Project, [Jamie Zawinski] is no stranger to frustration elicited from syntax errors, terrible implementations, and things that don’t work even though they should. This familiarity of frustration is what makes [jwz]’s command line controlled curtains so great; it’s rare to see someone so technically proficient freaking out over the lack of DHCP on an Arduino Ethernet.

[Jamie]’s project begins as so many do – modifying an existing piece of hardware to connect to the Internet. This is easier said than done, as [Jamie] fried a USB hub, FTDI cable and an Arduino Ethernet all at the same time. Finally turned onto the seeed relay shield, [jwz] got busy writing scripts to power his curtain.

Of course, this level of automation is nothing without a good bit of integration. After [Jamie] realized his projector (a Panasonic PT-D5500U) and receiver (Denon AVR-2805) could talk to his computer, he got busy mashing them together with a Griffin PowerMate. Mashing the button on the PowerMate turns on the projector and closes the drapes. There’s also a cron job running so that [Jamie] is reminded of the glowing orange ball in the sky.

Fixing The Control Scheme For An Aftermarket Headlight Assembly

January 12, 2012 by Mike Szczys 18 Comments

The headlight enclosures on [Bill Porter’s] 2004 Passat had yellowed with age and were not outputting the kind of light they should. He decided to replace them with some aftermarket modules that also incorporated LED strips. When they arrived he was surprised at how easy there were to drop into place. But when testing he was certainly not satisfied with how they worked. The day-driving mode used the HID bulbs at full power, where the factory assembly had dimmed them during the day. He set out to alter the electronics to work as he prefers.

Always the mad scientist, [Bill] started off by making a truth table showing how the lights reacted to the various states of the ignition and headlight switches. What he came up with is an AND gate built from a relay and diode. It allows him to have the LEDs on as the running lights (without the HIDs on at all), and leaves the rest of the functionality unaffected.