Recent News Articles
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:
...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?
SICK 2D Laser Scanner
Questions or Comments?
HOKUYO 2D Laser Scanner
Questions or Comments?
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!
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":
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...
Pigbot Today (07.11.2012)
Questions or Comments?
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...
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...
Robotics: Udacity CS373 - Programming A Robotic Car - Week 5/Unit 5
Another unit down, and one final unit to go! This week's unit was surprisingly easy, compared to others (especially last week's). It's focus was on more motion planning, with an emphasis on generating smooth paths, and control using a PID algorithm. For the final homework, we had to make a virtual "car" drive itself around an oval racetrack. While I was doing this, my car managed to kill several spectators before I finally got it under control!
Robotics: Udacity CS373 - Programming A Robotic Car - Week 4/Unit 4
I'm not going to write up a very long article on this unit; it was a real butt-kicker for me. It started off fairly easy, but then got grueling. Somehow I made it through...
Robotics: Udacity CS373 - Programming A Robotic Car - Week 3/Unit 3
Well, another week down, another unit done, and more homework behind me. This week's topic was all about another localization method called "particle filters". Using such a filter and a map with "landmarks", your robot can quickly and easily locate itself within that map. What's more, the amount of code required to implement such a filter isn't much, and what does exist is fairly easy to understand.
Robotics: Udacity CS373 - Programming A Robotic Car - Week 2/Unit 2
Wow! Where to start? This week was a cram week for me. Double ugh, but I didn't have much choice (well, I did - but my personality doesn't allow for it). Almost every day this week I worked late at my employer to implement an IPhone/Android app using PhoneGap and JQuery Mobile (both awesome technologies, btw - when they work). So most nights I had little to no time to concentrate on the class! I managed to get a few videos and such in here and there, but it was on Friday and Saturday that I put in the main time. I wasn't sure I would make it, but somehow I did! So what was this unit about? Kalman filters...