Arduino-Controlled Single-Leaf Shutter

October 23, 2013 by Phillip Ryals 4 Comments

[Kevin] has made an interesting camera shutter mechanism using an Arduino and a solenoid. To keep it extremely simple, he is only controlling a single leaf. In the linked video, you can see him take it through its paces from 1/125 seconds up to infinite. This is, of course, a proof of concept, and [Kevin] mentions using smaller components to make everything fit easily inside a Holga-like body. As he points out in the video’s comments, digitally controlling the flash would be a simple matter as well.

A basic camera is incredibly simple to make, and [Kevin’s] design certainly isn’t complicated. That said, if you look at the big picture, [Kevin] is demonstrating how feasible it could be to build an entirely custom camera with a standard microcontroller as the brain. We can’t help but think of all of the possibilities when you are able to control the entire photo taking process.

Interestingly, [Kevin] is also behind this twin lens reflex Kickstarter project from earlier in the year. It will be interesting to see what other camera-related hacks we will see from him.

Blender CAM – Open Source CAM Software

October 19, 2013 by Phillip Ryals 13 Comments

[Vilem] sent in a tip about a plugin he’s been working on for Blender, called Blender CAM. It allows for exporting directly from Blender to a G-code file. He has been working on it for several months, and releasing regular updates with various tweaks and improvements. While the project isn’t complete, [Vilem] has made some very impressive progress. It currently supports 2D and 3D strategies, various cutter types, simulation of 3D operations, and even automatic bridges.

The image above was made using the plugin, and it shows the level of detail possible. We can’t wait to see the 4 and 5-axis support that he is planning on adding.

A basic tutorial video is embedded after the break. As with anything Blender-related, it isn’t incredibly automatic, but another free tool is definitely a good thing. It looks like [Vilem] is looking for some other developers who could help out. If you have the knowledge, you might consider contributing.

Continue reading “Blender CAM – Open Source CAM Software” →

Going Mobile With Your Air Tools

October 16, 2013 by Phillip Ryals 34 Comments

If you’ve ever worked with air tools outside of a shop setting, you know that lugging the air hose around can get more and more annoying the further away you are from the compressor. [headsplosive] posted a video (embedded after the break) showing how to go mobile with your air tools.

Air tanks made for paintball are high-pressure in a tiny space, and make a very convenient energy source. In this case, [headsplosive] used a 68 cubic inch, carbon fiber wrapped tank rated at 4500psi. The normal regulator only steps that pressure down to 800psi, so he added a second regulator to hit the 120-140psi that air tools need. He then attached a ‘remote line’, or a coiled high-pressure hose, and added a standard air tool coupler at the end.

The yield is pretty impressive. With a half-charge of the tank, he managed to drive 100 two-inch nails. [headsplosive] has a scuba tank handy, and uses that to recharge the paintball tank. He estimates a scuba tank will last you about 2000 shots from a nailer, and only costs about $7.50 to recharge. Not bad at all. We can’t help but wonder how long you’d get out of an air-powered cutoff wheel, or even a hammer drill. While the parts aren’t terribly cheap unless you buy them used, it will still pay for itself in convenience if you have the need.

Continue reading “Going Mobile With Your Air Tools” →

Arduino-based Sieve Of Eratosthenes

October 10, 2013 by Phillip Ryals 25 Comments

[Darkmoonsinger’s] sister is finishing her graduate degree in mathematics, and [Darkmoonsinger] wanted to give her a gift that fit with her achievement. Naturally, building a Sieve of Eratosthenes using an LED matrix and an Arduino made perfect sense. If you’re unfamiliar, a Sieve of Eratosthenes is a simple, but very efficient, technique for finding prime numbers. Starting with a group of numbers, you step through each one in order. If it’s prime, you eliminate any multiples from the list. After a few iterations, the numbers remaining are all primes. After getting the LED matrix and sieve algorithm running, [Darkmoonsinger] designed an enclosure for the project. She made a couple of mistakes with this part, and happily included them for everyone’s benefit.

It only figures primes up to 64, and she lights the LED for 1 because it ‘makes the array look prettier’. Also, we couldn’t help but think that mounting the components a bit differently would have made a cleaner install (here’s a prime number generator with a backlit faceplate). However, that probably doesn’t matter to his sister. As they say, it’s the thought that counts, and we never get tired of seeing people build rather than buy!

Raspberry Pi Media Center On An Apple TV

October 3, 2013 by Phillip Ryals 8 Comments

You may tend to think of the AppleTV as a sort of walled garden, and you would mostly be right. Apple keeps tight control over what runs on their devices. That said, [David] decided to look closer at how the various ‘applications’ work. It turns out, the applications are nothing more than glorified web plugins. Using XML and Javascript, the apps simply define library function calls, giving them a consistent interface. So using fairly simply methods, the options really open up. Unfortunately, the method for adding new sites isn’t enabled by default.

Using a jailbroken AppleTV, [David] was able to do a fair bit of detective work and found a way to enable the ‘Add Site’ option, which allowed him to use his Raspberry Pi as a media server. The good news: you don’t need to jailbreak if you’re running 5.2 or 5.3… you should be able to recreate his success fairly easily. The bad news: things seem to have changed in 6.0. [David] isn’t sure if this was Apple intentionally closing a hole, or just not dotting all of their i’s.

[David] put all of his research up on Github, including the rough code. If you haven’t updated your AppleTV yet, and you have a Raspberry Pi to use as a media server, give it a try and let us know how it goes in the comments.

Restoring An Industrial Tractor

October 2, 2013 by Phillip Ryals 12 Comments

[Nickolas] dropped us a tip about a Youtube channel where [stevewatr] documents the restoration of an Oliver 770 tractor through no less than 133 videos. These videos span the last year, starting with finding the tractor in fairly dense undergrowth. He spends quite a bit of time troubleshooting the engine, explaining his thought process, and showing all of the steps he takes to get the tractor running reliably again. He also delves into fixes for the electrical and hydraulic systems.

In his tip, [Nickolas] said he just couldn’t stop watching, and we agree, this is really a fascinating series. One of the things we love about these videos is that [stevewatr] doesn’t filter out his mistakes. That means we get to see his failures and successes… Everything from how jump starting wasn’t possible with a small jumper wire, to getting the engine to start cold without a primer. That’s the beauty of our fail-of-the-week posts. Absorb it all, and you’ll be prepared when you run into related problems yourself.

[stevewatr’s] last video doesn’t show a completed tractor, so we look forward to seeing what happens as the project progresses. Even if you aren’t interested in having a tractor of your own, you can certainly use some of this information while building your own personal mech. Give it a try!

UTF-8 – “The Most Elegant Hack”

September 27, 2013 by Phillip Ryals 33 Comments

While it may not look like much, the image above is a piece of the original email where [Ken Thompson] described what would become the implementation of UTF-8. At the dawn of the computer age in America, when we were still using teletype machines, encoding the English language was all we worried about. Programmers standardized on the ASCII character set, but there was no room for all of the characters used in other languages. To enable real-time worldwide communication, we needed something better. There were many proposals, but the one submitted by [Ken Thompson] and [Rob ‘Commander’ Pike] was the one accepted, quite possibly because of what a beautiful hack it is.

[Tom Scott] did an excellent job of describing the UTF-8. Why he chose to explain it in the middle of a busy cafe is beyond us, but his enthusiasm was definitely up to the task. In the video (which is embedded after the break) he quickly shows the simplicity and genius of ASCII. He then explains the challenge of supporting so many character sets, and why UTF-8 made so much sense.

We considered making this a Retrotechtacular, but the consensus is that understanding how UTF-8 came about is useful for modern hackers and coders. If you’re interested in learning more, there are tons of links in this Reddit post, including a link to the original email.

Continue reading “UTF-8 – “The Most Elegant Hack”” →