A real car remote controlled with an Arduino… what could go wrong?

[Gilad] tipped us about his latest project, where he adds plenty of pneumatics and electronics into his wife’s car to remote control it.

The brake/throttle pedals are actuated by pistons controlled by electronic valves, and a standard DC motor is in charge of turning the wheel. The Arduino code tells us that the valves will be opened as long as the remote up/down channel is above/under given values. The frame is based on Festo aluminium profiles and we’re not sure where the mains used for the DC/DC converters is coming from.  As the valves use 24V and the motor 12V, standard N-Mosfets and power relays are used for voltage conversion. The remote controller [Gilard] used is actually 20 years old, so the output signal of the receiver isn’t actually really clean.

We do hope to never see this car on the road….

Build your own water rocket launcher

We feel like the days when you want to play in the water are far behind us. But if you can still find a warm afternoon here or there this water rocket launcher build is a fun undertaking. We figure most of the time spent on the project will be in shopping for the parts. They’re all quite common, and once you have them on hand it can be assembled in under an hour.

The concept is simple, but that doesn’t stop people from building rather complicated water rocket rigs. This one which [Lou] devised is rather simple but it does offer connections to a hose and air compressor (the alternative being to fill the bottle with water ahead of time and use a bike pump for air pressure). PVC is used to connect the two inputs to the bottle via a pair of valves. The bottle is held in place while water and air are applied. The launch happens when a pull on that rope  releases the bottle.

Check out the build process and bottle launch after the break. We think that rocket needs a few fins.

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Force carbonating root beer with dry ice

[Paul] is sick and tired of his homemade root beer being flat. He analyzed the problem with his carbonation techniques and ended up with a method of force carbonating beverages using dry ice.

He starts of by discussing the various methods that are used to carbonate beverages. There’s the old yeast and sugar trick that takes place inside of a sealed bottle. But this takes time, and if you don’t calculate the mixture correctly you could have over or under carbonated bottles (or exploding bottles in the case of glass beer bottling). [Paul] himself has tried the dry ice in a cooler full of root beer method. The problem is that the cooler isn’t pressurized so the carbonation level is very low. You need to have cold temperatures, high pressure, and the presence of carbon dioxide all at the same time in order to achieve high levels of carbonation.

His solution is to use a 60 PSI safety valve. He drilled a hole in a plastic bottle cap to receive the valve. He then drops a few chunks of dry ice in and seals it up. The valve will automatically release the gas as the pressure builds past the 60 PSI mark. What he ends up with is a highly carbonated beverage in a matter of minutes.

If you don’t mind spending some cash you can use an adjustable pressure regulator. This way you can carbonate just about anything.

[Thanks Steven]

Valve scoops up bright young electrical engineers

Several bright young engineers have been swiped up to work for Valve. Yes, that Valve, the game company. Amongst them are [Jeff Keyser] aka [Mighty ohm] and [Jeri Ellsworth], both names that we have seen on these pages many times. We’ve heard that Valve is a fun and very unique company to work for. Apparently there’s no solid hierarchy.

What we, and everyone else in the universe wants to know is what they are building! There were rumors and speculation of a game console that were quickly squashed. [Michael Abrash] let out some information in an interview that he was doing R&D into wearable computing. He also points out that he was not making a product.  So, let the speculation begin!

We asked [Jeri] if this meant she couldn’t publish her own hacks anymore due to contractual agreements, but she said that she can still do them and has some cool stuff coming out soon.

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Portal Radio is why Valve needs to build hardware

We’ve seen Portal gun builds, a few cute turret replicas, and even a miniaturized version of GLaDOS, but [John]‘s Portal radio replica is the first physical version of this oft-forgotten Portal item.

Interestingly, the entire radio is made from scrap. The spheroid body shell is made from the foam insulation from a commercial freezer, carefully sculpted, Bondoed, and painted over the course of 300 hours. The radio guts are taken from an upcycled radio, and powered by either an internal battery or a wall wart DC adapter – perfect for carrying around a test chamber with a portal gun.

Right now, there’s an AM/FM receiver inside the radio along with an audio input so an iPod or such can be plugged in. While we would have loved to see a loop of theuptempo version Still Alive, we’re guessing [John] hasn’t found an easy way to do that with junked parts yet.

Check out [John]‘s build video after the break.

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Build your own Portal turret in 150 easy steps

If there were a contest for the most thorough step-by-step project log [Kurt] would the champion. He recently a posted 150 step build log for his fleece-covered Portal turret project. If you can get over the need to click-through 30 pages of steps, there’s a lot to like about this project.

First, what it doesn’t do: The Turret doesn’t split up the middle and fire bullets at you. This is a relief, but the fact that it’s not lethal doesn’t mean it just sits there looking interesting. It can detect movement, it knows when you pick it up, and it can tell when it’s been knocked over. All of these interactive sensory inputs are used to playback various sound bytes from the Portal games, making it a great piece of desk art for those working in geek-centric offices. See for yourself in the video after the break.

The body itself is a food storage container which houses the barebones Arduino and Adafruit Wav shield. As near as we can tell, a PIR sensor detects movement, and leaf switches on the legs tell it when it’s been picked up or tipped over. But we only made a cursor examination of the assembly steps so we might be missing something.

If you’re not into the turrets, maybe this potato is more up your alley.

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This GLaDOS potato is a lie

Why settle for virtual reality when you can make the digital world into reality? [Josh] wanted to have a GLaDOS potato accompany him through life when not playing Portal 2. He set to work to see what kind of replica prop he could come up with. Judging from the image above, and demo video after the break, he nailed it right in the spud.

There’s no worrying about rot. The potato and a few parts were molded from Sculpey and baked in the oven. Since the fake spud is hollow in the center it’s easy to hide the bits that make it talk. An old MP3 player was loaded with quotes from the game, and plays them back via an LM386 audio amplifier circuit and a speaker hidden below the electronic eye. The eye is lit by five yellow LEDs which are also tied into the amplifier to make them blink and fade with the intensity of the audio signal.

A paint job and the nails and wire really make the build look just right. Now [Josh] needs to host a geek-themed Halloween party so he can really show this off.

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