phoenixgarage.org

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 Personal: TechShop is AMAZING!!!
What happens when you go to Desert Code Camp, then decide to leave early to head over to the Gangplank after-party, but find out they aren't ready for an hour, so while wandering the Chandler Rock-the-Block, you stumble across an odd sign with an arrow pointing down a side-street reading "This Way to TechShop"? Well, I guess you end up becoming a member...
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 Robotics: Low Cost Arduino LIDAR - An Approach
I found this interesting article, via an Arduino Forum thread, on how to hook up a low-cost true laser "tape measure" to an Arduino and read it via serial control...
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 Robotics: Differential Steering Using An Analog Joystick With The Arduino - Redux
A couple of years ago, I wrote an article on how to use an analog joystick (like those found in Playstation controllers) with the Arduino. I presented some code to steer a tank-like vehicle, aka "differential steering". Not too long ago, I posted how to do the same on the Arduino forum, in an updated manner...
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 Robotics: Laser Grid Displacement Experiment
What do you get when you take a laser module, some diffraction gratings, and a post on reddit?
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 Robotics: Low Cost LIDAR and Laser Range Finders: Where Are They?
The truth is, there aren't many options out there for low-cost 2D LIDAR systems. You basically have high-end sensor systems, like ones from the SICK Group and Hokuyo:


SICK 2D Laser Scanner
Questions or Comments?
    

HOKUYO 2D Laser Scanner
Questions or Comments?

...which can easily run into the several thousand (USD) range (if you want to see real expense, check out the laser system the Google Self Driving Car uses). Or, you have lower-end sensors, like the Parallax Laser Range Finder, at about $130.00 (USD), or you have homebrew DIY options. Where's the middle?

There really isn't one. The cost difference is mainly due to a number of reasons. For instance, the expensive sensors you see out there can scan very quickly, spit the data out quickly, work well in a variety of lighting conditions (up to and including daylight), use high-quality optics and lasers (plus IR filters and other systems to remove noise caused by other IR sources that can drown out the laser light), and they also generally use a form of interferometry to calc the distance (basically, you modulate the beam with a wave in the GHz range, and compare the outgoing beam with the reflected version - the difference between the waves is proportional to the distance measured - but you need really high speed timer circuitry for this). Some high-end sensors (so called LIDAR cameras) use time-of-flight and special high-speed optical sensors and timers to measure the time it takes from laser emission to reception of the reflected beam.

All other low-cost methods I've seen use triangulation (parallax) to measure the distance - because it is fairly easy and low-cost to implement (more on this later). The breakdown in costs on these methods, along with the high-end method, are summarized below (from greatest to least costly); What kind of LIDAR sensors can you buy with your hard-earned cash?

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 VR / AR: Oculus Rift Kickstarter: Make a Pledge - Change Gaming Forever...
I'm excited to be a part of this Kickstarter! I made my pledge to get a dev kit; I'm not sure yet what I'm going to do with it, but I might just have to haul out a bunch of my old VR gear and other junk, and take a crack at it once it arrives. Actually, I'll probably do that before it arrives. I had planned on integrating my VR gear into my UGV project, for a telepresence capability. There's also the possibility of pulling out some old Python OpenGL code I have and playing with that, too. Who knows! I am just glad that I could contribute to this project. I encourage you to do so as well!

 
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 General: Just a little change...
You may notice some slight differences here and there with the site. I decided to change things up slightly, to display a running feed of the last ten articles posted, and to not display "all articles" any longer - it was just making the site a mess. It's still possible to get to all articles, new and old (and there's no more archive, it was redundant). I updated the RSS feed to act the same way. I'm hoping this might improve my page rank a bit, but mostly I got tired of seeing only one article every time I posted a new one; my old aging system didn't make any sense. Enjoy!
 Robotics: Pigbot - Err...or another look at my first UGV
My first adventure into the world of unmanned ground vehicles (UGV) began here, with this ugly beast, which I affectionately named "Pigbot":


Pigbot Today (07.11.2012)
Questions or Comments?

I never took it any further, but it does showcase the creation of my first (and so far only) homebrew pan/tilt camera camera mount. A reader recently contacted me asking for some more information about the design of it, so I took some more pictures...

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 Robotics: Udacity CS373 - Programming A Robotic Car - Week 6/Unit 6 and Final
Well, I'm a little late on this for a variety of reasons, so I am going to try to keep this as short as possible. First, I completed Unit 6, which was all about SLAM - essentially taking everything we learned, plus a little more, and bringing it all together to control a robot. Overall, this went well; it was when the final came around that things got hairy, but I managed to get through it, too - and learned what the next class I need to take will be about...
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 Robotics: Udacity CS373 - Programming A Robotic Car: Why not understanding probability sucks...
Alright - this is really a posting, a plea for help, plus to keep a big chunk of stuff out of the discussion forum, as what I am about to post is likely a big fat SPOILER - you've been warned...
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