Monday, February 23, 2009, 01:28 PM - Misc TechnoToysThe WRAM show is an R/C modeling trade show that takes place every February at the Westchester county center in White Plains, north of the New York City. The show usually occupies two floor and the booths are filled with manufacturers, importers/distributors, and retailers showing their exotic gear. This year however, the show was rather disappointing and occupied only one floor. Many of the manufacturers that usually have a booth were absent, and many of the big on-line retailers like Hobby Lobby and BP Hobbies were absent. It looks like the economic crisis is having an impact.
- Trace En Poche (which could be translated as "pocket plotter") is an amazing on-line tool geometry, kinematics, and plotting tool. It allows you to enter descriptions of geometric figures using a GUI or a simple description language, and to plot and animate the result. The tool is available in a number of languages (French, English, Spanish, German, and Arabic). Thanks to Bertrand for the pointer.
- Command-line-fu: a bunch of random semi-non-obvious Unix/Linux command-line idioms to do various useful tasks. These simple tricks will occasionally aleviate the need to plow through the man pages of find, awk, egrep, sort, and such.
- Diamonds in the Sky: a collection of scientifically correct astronomy-related science fiction stories (sponsored by NSF).
- GPS homing device: Hammacher-Schlemmer has a simple GPS homing device for $80. Press a button when you are at a particular location, and the device will keep track of the distance and bearing to that location. It's small and simple to use. It integrated a self-calibrating digital compass in addition to a GPS.
Friday, February 20, 2009, 12:28 AM - TechnoPoliticsI went to see Universal Robots, the play by Mac Rogers at the Manhattan Theater Source yesterday. It's a fantastic play, very clever. The play is quite long (about 2.5 hours, or 3 hours including the intermission), but it is riveting from beginning to end. Each little dialogue and detail that seems gratuitous at first turns out to have major consequence for the future of humanity. The play feels like an elaborate scaffolding in which every small part plays an important role in keeping the construction together.
Practically every moral, social, and political issue raised by the possible emergence of intelligent robots is raised during the play: the military funding of scientific research, the political control of a unique and powerful technology, the role of human labor in an automated world, robotic wars, robot pain, robot morals, robot love, robot compassion, robot sex....
Go see the play. It's on until March 7 (and come to the panel discussion on Saturday Feb 21 at 3:00PM).
Tuesday, February 17, 2009, 02:53 AM - RoboticsThanks to Laurent Pinchart, maintainer of the uvcvideo driver, the Minoru stereo webcam now works on Linux.
If you are in a hurry to get it to work, here is the installation process under Ubuntu (or any Linux distro with kernel version 2.6.27-xx):
0. make sure you have installed the linux-headers package, probably called linux-headers-generic.
1. download Laurent's latest driver from linuxtv.org (click on the .gz link near the top of the page).
2. do "tar xvf <the-file-you-just-downloaded>". This will make a directory named "uvcvideo-XXXXXXX" in the current directory. cd to that directory.
3. do "make", and "sudo make install".
4. plug in the Minoru webcam.
The left and right webcams will appear as /dev/video0 and /dev/video1 (unless you already have a video device plugged in). You can grab from both cameras simultaneously at 640x480 at 15 frames per second, or 320x240 at 30 frames per second.
Thanks to Laurent for the quick fix, to Jan Ciger for testing the patches, and to Steve Jamieson and David Holder from Minoru for being supportive.
Friday, February 6, 2009, 11:06 AM - RoboticsThe Manhattan Theater Source in Greenwich Village, just north of Washington Square Park (and two blocks away from my lab at NYU) will host the play Universal Robots, a liberal adapation by Mac Rogers of Karel Capek's classic play R.U.R. ("Rossum Universal Robots", this is where the word "robot" comes from). The play will run from Feb 12 to Mar 7.
A Panel discussion will take place on Feb 21st from 3:00 to 4:00 PM entitled Resistance is Futile: Exploring our Evolving Relationship to Robots in Today’s Wired World. Panel participants will include my friend Michael Littman (from Rutgers), and yours truly, as well as artists and scifi writers.
Sounds like fun.
Saturday, January 31, 2009, 04:29 PM - Misc TechnoToysI just received one these brand new Minoru stereo webcam, which I bought at Amazon from 90 bucks (a steal considering the price of the closest competitor).
Naturally, I'd like to use it under Linux for robot vision, so I was crossing my fingers that one of the webcam drivers on Linux would recognize it.
As soon as I received the camera, I plugged it into my laptop running Ubuntu 8.10 Interpid. There are good news and bads news.
Good news: the device is detected by the uvcvideo driver, and the left and right cameras appear as /dev/video0 and /dev/video1. My video grabbing software was able to grab frames from both camera separately. I tried my own video grabbing test program written in Lush for v4l2.
Now for the bad news: it seems impossible to grab video from the left and right cameras at the same time :-(
It looks like uvcvideo assigns more than half the USB port bandwidth to the first camera, and there is not enough left for the second. I've posted a question about the problem on the uvcvideo developer mailing list. Stay tuned.
UPDATE: Laurent Pinchart, maintainer of the UVC driver is looking into the problem. It looks like the camera reports a higher bandwidth than it needs (at least, that's what how the driver interprets the data). The Minoru people are interested in making their camera work with Linux and are helping out Laurent (sending him a free camera and such).
Sunday, January 25, 2009, 12:10 PM - Misc TechnoToysChina Vasion (not China Vision, oddly enough) has a slew of cheap video gear such as wireless cameras and receivers for $25, and quad-camera systems for $100.
They also have rather unusual widgets, such as this underwater remote camera which comes with an MPEG recorder and costs $250.
The also have this radio-controlled car with a built-in wireless camera and a transmitter-mounted LCD screen. Things like this have been available for some time, but not for $90!
Monday, January 12, 2009, 07:22 PM - ElectronicsThis page (with an interesting domain name) describes a simple MIDI->control voltage converter that can be used to control analog synths from MIDI controllers. The contraption contains an arduino and an Analog Device AD5668 16-bit digital to analog converter chip. this chip has 8 independent analog outputs with 16 bit resolution, and uses an SPI (serial) interface. The chip can be had for $25 from DigiKey.
The most complicated part is to figure out how to talk to DAC chip, but the Arduino sketch source code says it all.
Monday, January 12, 2009, 12:38 AM - RoboticsThe Make Magazine blog has a link to this amazing DIY automatic book scanner from Japan. It's made out of Lego Technics and turns the pages of the book automatically. Very nice indeed.
Monday, January 12, 2009, 12:22 AM - Misc TechnoToysSteve Crandall from Tingilinde pointed me to this 150mW blue laser diode available for $50. An ideal way to fry your retina in the blink of an eye (actually *before* the blink of an eye, and way faster than it).
With proper precaution it might be used to build a CNC laser cutting machine to cut foam (Depron) and such.
Tuesday, January 6, 2009, 11:29 PM - RoboticsArduPilot is a small Arduino-compatible board designed to be the centerpiece of a UAV autopilot. It has servo outputs, a receiver input, a GPS input, and an input for a PIR-based stabilization sensor (such as FMA's Copilot).
Sparkfun has the kit for $25, except that they seem to be out of stock right now. The SMD components are pre-soldered on the PC board.
Monday, December 29, 2008, 04:24 PM - RoboticsThe G-Dog is a new robot dog kit from Japanese company HPI Robots, a division of HPI Racing, which sells R/C models and techno-toys of various kinds.
The G-Dog sells for about 70,000 Yens (about US$800).
This YouTube video shows the speed and agility of the G-Dog. It's much faster than the Aibo ever was. Then again, unlike the Aibo, it doesn't have a nice-looking shell, and has a rather simple on-board computer and few sensors.
It uses 9 custom servos, dubbed RS304MD, which seem to be controled through a TTL-level serial port. The CPU is based on an Atmel AtMega128, and includes a 3-axis accelerometer. It has interfaces for 2 gyros, and a wireless receiver.
The G-Dog weighs 570g, which is quite light, but could be made lighter with the use of LiPo batteries instead of NiMH.
If only this things became available outside of Japan....
Friday, December 26, 2008, 08:06 PM - Misc MusicI've been playing with my new Akai's new EWI USB for a couple of weeks now. I have to say, it's a mixed bag. Compared to the more expensive EWI 4000-S, there are pros and cons.
Let's start with the pros: it's a lot cheaper than the EWI 4000-S ($300 versus about $600), it's lighter (no built-in battery, no built-in synth), it's powered through the USB cable, and the breath, lip, pitch-bend, and key sensors are essentially identical to the 4000's, except that they are self-calibrating. Now for the cons: my main gripe is the absence of portamento sensor. The 4000 has a slider on the right side of the octave rollers that, when touched with the left thumb, turns on the portamento (or glissando). I love that feature, but it's absent from the EWI USB.
Second, since the EWI USB doesn't have a built-in synth, it comes with a software synth that runs on PC/Mac. The sounds provided with the soft synth are few and not so great. Many of them do not even react to the EWI sensors (like the pitch bend or breadth control). So, you will need another soft synth if you want decent sounds. I tried to install the soft synth on Linux under wine. The good news is that it runs. The bad runs is that the latency is so high that it's unusable. I'm not sure where the latency comes from, or whether it's fixable.
Saturday, December 6, 2008, 01:02 AM - Misc MusicAkai has announced the availability of the EWI USB, the latest product in their long line of Electronic Wind Instruments. The EWI USB sells for about $300 at Sam Ash, Sweetwater, and other online music instrument stores. It look similar to the EWI 4000S, but has a USB port instead of a MIDI port, and has no built-in sound module. Instead, the EWI USB relies on software synths on PC or Mac to produce sounds. Getting rid of the built-in analog emulation synth allows Akai to bring down the street price from $700 for the EWI 4000S to $300 for the EWI USB.