In April 4volt.com turned 10 years old, that’s a whole decade of weird stuff, lots of posts and files. Here’s a picture of me modding a PlayStation in 2001, at the time this site was just getting started and the internet was a relative wild wasteland. I’ve also moved this site to a new server after running it for 2.5 years on a server in my basement. Here are some fun facts about stats over the last couple years: Total hits: 14,286,663 Average hit size: 32.53kb Total Visitors: 907,787 Browsers...
Last weekend I was in a team that entered a short film into the National Film Challenge, under the name a3o Studios.
The film we made was filmed on the Canon t2i / 550d in 1080p 24fps. The quality of the film is so good that it seemed a shame to burn it onto a standard def DVD and loose all that detail, especially when it was going to be shown on a TV that was capable of showing all that detail. Of course I could hook my computer to the TV, but that’s no good for distribution.
That quandary got me...
Trammel Hudson of Magic Lantern fame has started porting the custom Magic Lantern firmware to the cannon t2i / 550D.
So for it seems to be an alpha release, but I suspect that things will start moving more quickly now.
In this first release the only new features appear to be audio monitoring and lens info, but that is a great start.
In my opinion the poor audio quality of the t2i is in my opinion the biggest flaw the camera has right now. With manual audio control and a little skill, I think the t2i could be used to shoot feature...
I’m always happy when I find a new kind of part that is cheap and easy to use with DIY electronics projects or robotics, the more standardized the better.
There’s a whole world of smart electronics and helper things in the hobby and remote control world that are great for robots and other things.
You probably already know that hobby servos are easy to control from any microcontroller like the arduino, but there are a bunch of other things that are just as easy to use. Generic motor controllers, battery systems are also equally as useful, but are sometimes hard to sort...
I got my hands on the Canon T2i and I ran it though it’s paces, the things I was most interested in was the video modes and low-light performance.
To see the HD version downsized to 720p, you have to load the video from vimeo directly: Canon T2i, 550D Practical Video Tests.
T2i Vs. 7D
First a quick word about the T2i vs. the 7D. The T2i does not have that pro-feel that the higher level cameras have. The body is fairly light and it is most defiantly made of plastic, and you can tell when you hold it. For me...
Over the last few years HD video has been getting constantly cheaper, easier and better. I bought a used HD camera in 2001 (JVC HDGR1) for about $2,000 that was one of the first cameras under $10,000 that could do HD, and that it does at 720P, with some other deficiencies. For a while now cheap HD has been available, for instance last year I bought a $150 camera that could also do 720P, but the sensor was small and noisy, that and the audio quality made the footage unusable. However now the latest versions of digital...
Recently, I posted a article about how much computational power it would take to emulate the human brain, and my calculations were off by a factor of 10. I've corrected my estimates and here are the updated sections:
Emulating the Human Brain
The Blue Brain Project has successfully simulated 1 cordical column on the Magerit super computer (100 TeraFLOPS), and human brain has an estimated 1,000,000 columns.
So with 5.2 ExaFlops, one could emulate 52,000 cordial columns. And that’s 1/20th of enough power to emulate a human brain.
To emulate the entire human brain you would need approximately 100 ExaFLOPs
That's a lot of...
As a brain exercise I decided to try and estimate the total processing power of all the computers on the entire internet, and see if that is enough processing power to emulate the human brain.
Since this is an estimate, I will try my best to figure it out with public data.
Here was my process:
Total Number of Computers
No one knows exactly how many people (computers) are connected to the internet since a single IP address can be shared with any number of pc’s, but the best estimate I was able to find was here: Internet World Stats
They use population statistics...
This past week I was at CES doing market research, and I'm sure everyone reading any of the tech/gadget blogs have had a overload of CES related coverage. I’m not going to talk about any of the things that got major coverage, but here’s some general thoughts, and a couple things you probably didn’t see anywhere else.
3D TV is coming at you like a 900lb gorilla
Pretty much every TV/Monitor manufacturer has a 3D version of a product coming out, and with Blue-ray updating it’s standards to...
After having the new Motorola Droid for about a week, I've been very impressed with it’s features, usability, and experience.
Previously I was using a windows mobile phone, and as far as usability goes, Android is leaps and bounds better then even the latest (6.5) version of Windows Mobile.
Although, when I show my phone to an iPhone users, they generally complain about the lack of multitouch, especially in the web browser, and the on-screen keyboard. I think that feature alone will end up being a major sticking point when people talk about switching from the iPhone to the Droid.
Way back in 2002, I ran an experiment with a hard drive to see how durable the inside actually is, mostly curious to see how easy it is to ruin a drive. In the 2nd above photo you can see the drive arm moving, all of these photos were taken while the drive was being used in a live system. We removed the cover of a old IDE hard drive and proceeded to format and install windows. We didn’t make any attempt to protect the drive, and the office we worked in...
Todbot has posted an excellent tutorial on how to setup and use the minimal Arduino, which is the bare minimum you need to run a ATmega chip and the Arduino bootloader. Todd goes into detail about how to get the bootloader onto the chip as well as how to setup the Arduino environment to use it. Even if your not interested in building an Arduino from scratch, It’s a good read if you are interested in the technical aspects of what makes the Arduino work. http://todbot.com/blog/2009/05/26/minimal-arduino-with-atmega8/
I’m starting on a project that I’ll be using stepping motors and belts, and after looking for cheap parts online, I thought I could do better by stripping down some old scanners.
People are excited to get rid of there old computer stuff, the great thing is it doesn't matter if the old scanner works. Even if it doesn't turn on likely the motor and mechanical parts are still good for salvage. I posted a ad on Portland’s craigslist in the wanted section and got several responses, in a week I had a bunch of scanners for free, I only...
It’s no secret that I’m a fan of Theo Jansen’s work, he is the inventor of the Jansen Mechanism that I used as the basis of my recent Jansen Walker project.
Jansen was recently interviewed on the generically named "Robots Podcast" where he spoke about his thoughts on if he was a artist or scientist, if the Strandbeest have thoughts, his building materials, the design of the legs, how he would like the Strandbeest to outlive him, also microcontrollers and commercialism.
Check out the podcast over at Robots Podcast.
I’m officially releasing my Jansen Walker as a beta with the source files and a video!
4volt Jansen Walker Beta 1 Video
Jansen Walker: An openly designed Creative Commons licensed robot.
What you see here is the Beta 1 version of the walker, a laser-cut robot, based on the Jansen Mechanism. It has 8 legs and scuttles similar to a crab walking sideways. The brain is a Arduino, and the legs are powered by 2 micro-servos modified for continuous rotation.
If you would like to buy a kit of just the plastic in its current state, check out the...
There are many ways to power your next project but I’m quite partial to the continuous rotation servo because it’s very easy to hook up to your micro controller, you don’t need to build or buy a separate controller or h-bridge to power the motor. In a servo all that is built in. All you need to do is connect the power directly to your battery and send a low-voltage control signal to tell it what you want it to do.
Servos out of the box are meant to rotate in a fixed range of 180 degrees, but modifying them for...
Update Note: While I'm keeping this post for historical value, this post is not kept up to date with my Jansen Walker, look at the Jansen Walker project page for the latest details and plans.
If you’ve been following my posts lately I’ve been putting a bunch of my time into a robotics project that uses the Jansen mechanism for movement, if your not familiar look below for an animation.
I've spent quite a bit of time on the mechanical design on this robot, maybe more then was strictly necessary since I used this opportunity to learn SolidWorks, and since...
Zignig from Thingiverse posted a python script called "Parametric Papercraft" that will draw boxes of any size based on my folded box design. It’s a cool idea that I highly recommend checking out.
The sony PSP (pay station portable) is a great piece of hardware, a nice big screen with a decent processing power along with a some good controls and a fair amount of software features right out of the box. In my opinion the biggest competitor to the PSP is the iPhone and the iPod touch, though there are not directly equivalent. The problem with the stock firmware is that it’s locked to sony signed apps, running an alternative firmware will let you run homebrew code. There’s a plethora of conflicting info on how to flash the psp, There...
In my current PC I have two power supplies, one for my motherboard and accessories, and one for my raid array.
The problem is, you cant just use a regular ATX PC power supply for dumb power without hooking it up to a motherboard. Fortunately there’s a (fairly) easy way around that. There is a wire in the main 20-24 pin ATX header that tells your power supply to turn on, and is usually the only green one.
Before we get into the details, here are two warnings:
There are dangerous voltages in your power supply, if your not...
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