Indeed, the gizmo above is meant to be used as a gas pedal. [Grant Skinner] came up with the idea to control slot cars using an Android phone as a gas pedal. He coded the software for the handset and a computer using Adobe AIR. Once connected, the computer is sent the accelerometer data from the phone, relaying the speed control to the slot car track with the aid of a Phidgets motor controller. See it ‘go’ after the break.
Do not put anything in this box that you will need in a rush. You’ll have to successfully guess the word in a game of hangman to gain entry. He’s using an Atmega328 as the brains of this project with a rotary dial and an LCD for input and display. If you win, the box is unlocked and you can open it up to get whatever is inside. There are links to various tutorials along the way to help with each step, including the Arduino source code he used to build it. We think he should bump it up a notch and have the box destroy the contents if you fail. Sounds like fun, right?
[Pablo] likes to buy and repair broken cameras. When he was in need of a way to test the shutter speed, his brother came up with a great idea. Harvest the photo transistor from an old ball mouse. It turned out to be just as easy as it sounds. He plugs the circuit into some sound editing software to get the signal. We think this is pretty slick.
Standard connectors in portable devices would be great for the consumer, but then you wouldn’t purchase separate peripherals for ever portable you buy (lining the pockets of the companies licensing said peripherals). [Thijs] isn’t taking it lying down any longer. Realizing that the shape of the connector is one of the only things standing in the way, he built an adapter to use iPod docks with Droid. The hardware consists of a USB connector, audio jack, iPod connector, and a magnet. After working out the wiring it was just a matter of building a chassis using polymorph material. As you can see above, his expensive dock has no problem playing nicely with Droid because of his handy work.
PVC, wood, and some creativity bring this Stargate duplicate to life. [Mango] and his father started with AutoCad drawings taped together, and ended with the Stargate you see before you. Sure it’s not 22 foot in diameter and not made of Naquadah, but its inner ring rotates and dials like the real thing and it has all 39 symbols – hand carved. Catch a fun and entertaining video with the Stargate after the break.
The idea of the Great Ball Contraption is to take modules from many builders and combine them into one large machine. The modules need to find some way of moving LEGO soccer balls and basketballs from an input point to an exit are that passes them onto the next module. Some of them sort the balls, but in the end the eight-and-a-half-minute video above shows the orbs going around and around. That’s just fine with us, it’s no secret that we love machines that are overly complicated and may be completely useless.
[Colin] has cut his teeth with about fifteen PCB orders. He wrote a tutorial describing the process and sharing his tips on avoiding common problems. You may remember our own How-To prepare designs for manufacture early last year. In that post, [Ian] shared his veteran knowledge by outlining BatchPCB’s board design process. This time, [Colin] is using Advanced Circuits in Colorado as a board house, giving us more insight on how the different companies work. No matter who you choose for manufacturing, make sure you really understand how to properly format and troubleshoot your designs. It’ll end up saving you a lot of time and money.
As the summer heats up an air conditioning system is a necessity in many climates. [Grayson's] system suffered some damage over the winter that caused it to vent its refrigerant, avoiding an explosive situation. Before he can chill out inside he’ll need to recharge it and he’s chosen to use propane in his cooling system. According to our friend Google this is not his original idea, but has been done many times before. [Grayson] makes the point that although propane is flammable it’s not necessarily any more dangerous in a fire than Chlorodiflouromethane, or R22, which is the nasty little gas that fled his system for its new home in the upper atmosphere.
The video above includes a brief explanation of recharging the system and the tools needed. We’d need to mill this over for quite a while before working up the gumption to give it a try. For now we’ll stick to [Grayson's] more pedestrian hacks like making some servo motors sing or easing our yard work woes.