Yann's Techno Toys Blog2010-03-12T16:37:40ZYann LeCunCopyright 2010, Yann LeCunSPHPBLOGAerotrain: the documentaryAerotrain was a French R&D project headed by engineer Jean Bertin in the 60's and 70's to build a high speed hovercraft monorail. The first prototypes of the Aerotrain used gas turbines for levitation and propulsion. Later models used a linear motor for propulsion and gas turbines for levitation. There are a few fan sites, that trace the history of the development .
Interestingly, the technology was licensed to an American company in Colorado called Rohr Industries. They developed and tested a prototype, but the project was later abandonned.
The project received a lot of publicity in France in the late 60's and early 70's when I was growing up. A friend of my aunt's was a young engineer at Bertin in the early 70's, working on the Aerotrain. Growing up, I was totally fascinated.]]>http://www.lecun.org/blog/index.php?entry=entry100308-1800532010-03-08T00:00:00Z2010-03-08T00:00:00ZPersonal Electric VTOL aircraft from NASAan article on the Puffin.
The Puffin has two contra-rotating propellers in the front, and four tail booms with tail planes that fold out to turn into a landing gear for vertical landings. The pilot "stands" in the plane (when sitting on its tail), and lie on his belly when the plane flies horizontally.
The 4.1m-wingspan plane is powered by a 45kg lithium-phosphate battery that gives it a range of just 80km at a cruising speed of 240km/h, but progress in battery technology could triple the range over the next 7 years. The motors have an approximate total power of 45kW.
]]>http://www.lecun.org/blog/index.php?entry=entry100121-0035092010-01-21T00:00:00Z2010-01-21T00:00:00ZOperation: No Smoking May 16th, 2010 Plerguer, FranceAero-Modèle Club de la Côte d'émeraude (AMCCE) in Plerguer, near beautiful Saint-Malo, France, is organizing an all-electric fly-in on May 16th 2010. They call the event Operation No Smoking. The website shows pictures of several electric planes from yours truly (I spend some of my summer vacation nearby and fly there on week-ends).
Here is a satellite pic of the flying site:
View Larger Map]]>http://www.lecun.org/blog/index.php?entry=entry100118-1155072010-01-18T00:00:00Z2010-01-18T00:00:00ZParrot AR.Drone: super-duper wifi-enabled, Linux-based quadricopter with visionParrot AR.Drone is a very exciting and very unusual quadricopter: it is Wifi enabled and has two on-board cameras. At first glance, you could think of it as a flying version of the Rovio. Essentially it is a self-stabilized flying wireless webcam. But the AR.Drone has much more to offer to TechnoToy enthusiasts: it comes with a "shared source" API that allows any wifi-enabled device to get video and sensor data from it and to control it. The website has a number of drool-inducing videos of iPhone controlled AR.Drones, and augmented reality games in which AR.Drones appear to fight giant robots or appear to shoot lasers at each other.
The specifications are nothing short of amazing, really a dream come true for anyone interested in tinkering with flying robots: 6 DoF IMU (3 accelerometers, 3 gyros), 468MHz ARM9 CPU running Linux (which should open the door to custom firmware hacks), an ultrasound altimeter/ground detector that allows automated takeoff and landing. Last but not least, there are two cameras: the first one looks down and is used for vision-based stabilization and ground target detection (176x144 resolution, 60fps, 63 degree field of view). The second camera (640x480 resolution, 15fps, 93 degree FoV) looks forward and its output can be streamed through wifi.
There is no price and no release date, but I'm guessing this is not going to be cheap.....
The coolest aspect of the whole thing is that it is hackable. There is a developer website with a Wiki and downloadable source code (registration required). The system is "open" but not open source in the traditional sense (the license of the API is not an open source license).
Even more interesting, the protocol to communicate with the AR.Drone from the ground (e.g. from an iPhone or a Linus box) is documented in the Developer Guide. Apparently, it consists in sending a bunch of "AT"-style command through a Unix socket. Nice.
The puzzling thing is that Parrot is a French company which, until now, was involved in high-end cell phone audio accessories and expensive designer digital photo frames. What prompted this 400-employee company founded by a former journalist to get into the hobbyist/toy business? Perhaps the fact that their CTO used to work at Arianespace?]]>http://www.lecun.org/blog/index.php?entry=entry100107-0255572010-01-07T00:00:00Z2010-01-07T00:00:00ZiPhone vs Droid, XKCD style.
link to more XKCD. ]]>http://www.lecun.org/blog/index.php?entry=entry091225-1122572009-12-25T00:00:00Z2009-12-25T00:00:00Z6 DoF IMU + ArduinoDIY Drones store has a very useful piece of hardware: the ArduIMU+ v2. It's an Arduino-compatible board with a 3-axis accelerometer chip and a 3-axis gyro chip with appropriate filters. It also has a connector for a GPS module (with a 4Hz refresh rate). All of this for $100 (plus $90 for the GPS). Very useful.]]>http://www.lecun.org/blog/index.php?entry=entry091220-1602222009-12-20T00:00:00Z2009-12-20T00:00:00ZModifying an ESC for digital speed controla whole thread about this on RC Groups, as well as a PDF file with detailed instructions, and schematics.
The alternative is to buy an I2C compatible ESC from YGE: 60 Euros (about $90) for the 18A YGE-18i, or 70 Euros ($115) for the 30A YGE-30i. Ouch!
Speaking of which, for you ESC DIYers, Fairchild has a 40V, 20A, Dual N & P channel mosfet pair, the FDD8424H (available at Mouser for $0.86). ]]>http://www.lecun.org/blog/index.php?entry=entry091130-1550412009-11-30T00:00:00Z2009-11-30T00:00:00ZMicro heli and 3D-capable plane from e-FliteBlade mSR ultra-micro helicopter, and the 4-Site ultra-micro 3D airplane.
The Blade mSR comes in an a "bind-and-fly" version for $150 (requires a separate Spektrum 2.4GHz DSM-compatible transmitter), and an RTF version for $180 (which includes a transmitter). The rotor diameter is 180 mm, and the mass is 28 grams. It uses a 120mAh single-cell LiPo battery. It's available from Hobby Lobby, and from Red Rocket Hobby.
According to some reviews, the Blade mSR is the first single-rotor (non-coaxial) micro-heli that flies well. Most single-rotor micro helis have a separate motor for the tail rotor. These motors have relatively long reaction times, which makes the heli rather difficult to fly (they will rotate every time you increase or decrease the throttle). The Blade mSR is so tiny that the inertia of its tail rotor is very small, and the reaction time is very short.
The 4-Site Ultra-Micro comes in 2 version: "bind-and-fly" for $170, and "PNP" for $110. A Spektrum DSM-compatible transmitter is required. The wingspan is 386 mm, and the mass is 35.5 grams, with a single-cell 150mAh LiPo battery. e-Flite has other such small planes, but this is the first 3D capable ultra-micro from them. The plane includes a 5-in-1 P board with a 2.4GHz DSM receiver, a brushed speed controler, and two linear servos. Two additional servos for the ailerons are pre-mounted on the plane. It's also available from Hobby Lobby, and from Red Rocket Hobby.
]]>http://www.lecun.org/blog/index.php?entry=entry091130-1318012009-11-30T00:00:00Z2009-11-30T00:00:00ZShrediquette: an Arduino-based Tri-copterShrediquette is a tri-rotor helicopter built by William Thielike from Germany. William is a PhD student in biology, who seems to have many talents: micro-controller system design, control, mechanical design, flying contraption construction, as well as film making.
His tricopter is built around an Arduino Pro Mini micro-controller. Oddly, William didn't use the Arduino development tool and C/C++ programming language: he wrote his software in Bascom, a dialect of BASIC.
The yaw control is performed by rotating the tail boom with a servo. This very unlike the more conventional servo-less yaw control of quadcopters, but it's practically unavoidable for tricopters.
http://www.lecun.org/blog/index.php?entry=entry091130-1302242009-11-30T00:00:00Z2009-11-30T00:00:00ZeRC Micro P-51 Mustang RTF for $99Hobby Lobby has the eRC Micro P-51 Mustang for $99.00. The diminutive ready-to-fly warbird has a 37 cm wingspan, weighs 30 grams, and comes with a 4-channel 2.4GHz radio. The plane has proportional control for the ailerons, elevator, and throttle. It uses a geared brushed motor.
Apparently, there is no rudder control as with the similarly sized Kyosho Minium Piper Cherokee. But the Minium is $180....
They will be rolling out a spitfire in December.]]>http://www.lecun.org/blog/index.php?entry=entry091103-0005212009-11-03T00:00:00Z2009-11-03T00:00:00ZDavid Berkman at SmokeDavid Berkman was playing at the uptown club Smoke yesterday and Friday with Antonio Hart on the sax, Ted Poor on drums, and Ed Howard on bass. I went to the last set on Saturday and it was awesome. David has a new CD out entitled Live at Smoke (also on Amazon MP3 downloads), with live performances of some of his fantastic pieces from earlier records, like Weird Knack, which appeared on his amazing 2000 CD Communication Theory (though it was mispelled "Weird Knock" on that CD). Interestingly, David post the scores of many of his compositions on his website (though the links seem dead right now).
In fact, I first heard of David Berkman while listening to the WBGO radio station back in 2000. They played a piece from Communication Theory. I was hooked.
David played on Joel Frahm's first two CDs ("Sorry, No Decaf", and "The Navigator"), and composed some of the pieces on these CD (like "Interesting perhaps, but hardly a fascinating rythm"). It would be awesome if David and Joel could record together again. It would also be awesome if David played more often in NYC, particularly downtown.]]>http://www.lecun.org/blog/index.php?entry=entry091101-1443082009-11-01T00:00:00Z2009-11-01T00:00:00Zttymidi: serial/usb to MIDI for linuxTTYMIDI is a linux hack to allow any serial or serial/USB device (such as the Arduino) to produce MIDI events compatibel with ALSA in Linux. This makes it easy to turn any Arduino-based hack into a MIDI controller. ]]>http://www.lecun.org/blog/index.php?entry=entry091017-2226592009-10-18T00:00:00Z2009-10-18T00:00:00ZOmer Avital with Joel Frahm and Bill CampbellBar Next Door, Joel Frahm and Bill Campbell were accompanied by bassist Omer Avital (instead of Joe Martin). The second set was particualry energetic, with one of Omer's composition called Flow, which is based on the changes of Giant Steps. I had never heard Joel play giant steps. Pianist/Composer David Berkman says in his book that Joel plays a mean Giant Steps. He is right, despite Joel claim that he hadn't played Giant Steps in while and was a bit rusty. ]]>http://www.lecun.org/blog/index.php?entry=entry091017-2100572009-10-18T00:00:00Z2009-10-18T00:00:00ZJoe Martin's latest albumJoe Martin's latest album,'Not By Chance', has been out for about a month now. It features Joe at the Bass, Brad Mehldau on Piano, Chris Potter on Sax, and Marcus Gilmore on Drums. What a nice line-up! Go Joe, go. ]]>http://www.lecun.org/blog/index.php?entry=entry091012-1725432009-10-12T00:00:00Z2009-10-12T00:00:00ZGadi Lehavi: 13 year-old Jazz piano prodigy His playing is amazing for a boy this age. Actually, it's amazing, Period. He is classically trained, and has been playing Jazz for about a year and a half.
]]>http://www.lecun.org/blog/index.php?entry=entry091012-0029552009-10-12T00:00:00Z2009-10-12T00:00:00ZHydroptere sails at over 100km/hL'Hydroptere, a sail-powered hydrofoil beat the speed record for a wind-powered watecraft with an average speed of 51.36 knots over 500 meters. The boat reached peak speeds of 103 km/h. Back in 2008, it briefly reached over 110km/h shortly before it capsized. L'Hydroptere has been in development since the early 90's under the leadership of Alain thebault. This idea was born in the mid 70's following a discussion between a group of aeronautical engineers and French sailing legend Eric Tabarly.
The previous 500 meter record was held by French kitesurfer Alex Caizergues at 50.57 knots.
]]>http://www.lecun.org/blog/index.php?entry=entry091010-2158592009-10-11T00:00:00Z2009-10-11T00:00:00ZOur Experiments with Engine Sound Synthesizer for Electric Airplanesengine sound generator that could be mounted in an electric model airplane. This would allow scale models to not only look realistic, but also sound realistic, more realistic in fact than gas-powered model airplanes.
Other people have built engine sound generators before, but my dad's idea was to synchronize the pitch of the sound to the speed of the propeller.
After some semi-succesful experimentations with simple eeprom-based circuits, we built a sound synthesizer using a microcontroller module with some custom software. The module was a Tini2138 from New Micros, which has a 60MHz ARM7-TDMI with 512KB or eeprom (plenty of room for sound samples), and a 10-bit DAC.
The system worked quite well, but it's rather bulky and complicated to build for the average hobbyist. We are now developing a new version based on the hugely popular Arduino microcontroller platform. The new system is considerably more simple and lightweight, and will fit into small park-flyers. Stay tuned....]]>http://www.lecun.org/blog/index.php?entry=entry090914-1155392009-09-14T00:00:00Z2009-09-14T00:00:00ZFlymentor3D: Vision-Based Flight Stabilization for R/C Helicopters and AirplanesShenzen KDS Model Technologies proposes a new type of flight stabilization system for model helicopters and airplanes called the Flymentor3D. Instead of the usual separate gyros, the system uses an all-in-one IMU (not clear if it contains a 3-axis accelerometer or just 3 gyros), and a CCD sensor with a vision system. The CCD camera points down and can detect movements relative to the ground, presumably using some sort of optical flow calculation. The processing involved is similar to what takes place in an optical mouse, and in fact, I suspect they use the same chips.
There is a downloadable manual in PDF for more details (in semi-non-broken English). Unfortunately, no price is given on the KDS website.
The nice thing about vision-based stabilization is that there is no drift, unlike with gyros and low-cost IMUs. The helicopter will stay exactly in the same place with the same heading for as long as you want.]]>http://www.lecun.org/blog/index.php?entry=entry090910-1421092009-09-10T00:00:00Z2009-09-10T00:00:00ZAir Hogs Switchblade Amazon has it for pre-order for $70.
There is a test video on YouTube.
]]>http://www.lecun.org/blog/index.php?entry=entry090910-1412052009-09-10T00:00:00Z2009-09-10T00:00:00ZA week with the Samsung Galaxy i7500 Android phoneMobileCityOnline.com. This is a $600 unlocked import model built for the European market. T-Mobile isn't schedule to distribute the phone in the US until later this fall, and I use the phone with AT&T anyway (since I don't get any T-Mobile signal at home).
Problem #1: The main issue with using the Galaxy with AT&T (or any existing Android phone for that matter) is that AT&T uses unconventional frequencies for 3G that are not supported by any Android phone. Hence, using an Android phone with AT&T means being restricted to 2G and Wifi. It sucks, but it sucks less than having no signal at home.
Setting up the phone to work with an AT&T SIM card posed no problem. The Settings->APN entries are as follows: Name: anything_you_want APN: wap.cingular Username: wap@cingulargprs.com Password: cingular1 MMSC: http://mmsc.cingular.com MMS Proxy: wireless.cingular.com MMS port: 80 MCC: 310 MNC: 410
Problem #2: the version of the firmware/software installed on the unlocked Samsung phone is essentially unusable in the US. There is no "Market" app to download software from the Android market, no automatic switching of the screen from portrait to landscape, no access to the accelerometer and magnetometer. Fortunately, the fix is easy: you can flash the latest version of the firmware (H7), and everything will work fine. The procedure is quite simple and described here. You will need a Windoze machine to run the MultiOdin ROM flashing utility.
Thank you kam187 from androidforums for the trick.
The phone is simply fantastic.
]]>http://www.lecun.org/blog/index.php?entry=entry090907-0122262009-09-07T00:00:00Z2009-09-07T00:00:00ZAnother foam cutter CNC kitRCFoamCutter has a number of kits of CNC machines for cutting foam costing $400 for a basic kit to about $1300 for a complete kit (including electronics, hot wire power supply and such). ]]>http://www.lecun.org/blog/index.php?entry=entry090827-0318432009-08-27T00:00:00Z2009-08-27T00:00:00Zmbed: ARM7 microcontroller with online toolchainmbed microcontroller uses such a cool new concept that one wonders why we haven't seen this before: an online C++ toolchain/development suite. The mbed microcontroller board uses an open design built around a 60MHz NXP LPC2368 ARM7 CPU (datasheet) with 512KB flash, 32KB RAM, USB 2.0, 10/100 ethernet, SD/MMC interface, 2xSPI, 2xI2C, 3xUART, 1xCAN, GPIO, 6xPWM, 6xADCs, and 1xDAC. The library apparently contains simple Arduino-like functions for I/O and such.
It's still in beta at the moment, and the board is supposed to cost about $65 50 UK Pounds, or about $85.
There is a number of articles on the mbed at Elektor, and at Circuit Cellar (PDF). ]]>http://www.lecun.org/blog/index.php?entry=entry090827-0304152009-08-27T00:00:00Z2009-08-27T00:00:00ZMaple: ARM-based Arduino coming soonLeaflabs blog has a post about the prototype of a rather appetizing Arduino-like micro-controller board built around an STM32 ARM Cortex-M3 from ST Micro.
The folks at Leaflabs apparently intend to make the board work with the Arduino software suite, and implement an Arduino compatible library. Many of us are drooling at the prospect of an ARM-based, $40 Arduino-quasi-compatible board. It would enable projects that are out of reach of the current Atmega-based Arduino, such as real-time audio processing. It would certainly help that the STM32 has three super-fast 12-bit ADC, as well as two 12-bit DACs! Hello Arduino-based synthesizer modules!
It's not clear which the 3 zillion versions of the STM32 the board uses. ]]>http://www.lecun.org/blog/index.php?entry=entry090822-1246522009-08-22T00:00:00Z2009-08-22T00:00:00ZAudio D-Touch: Tangible musical interface from EPFLAudio D-Touch. The site includes instructions for building your own d-touch system, as well as downloadable code for Windoze, Mac, and Linux (registration required).
Applications include a drum machine and a sequencer.
More videos are available here. ]]>http://www.lecun.org/blog/index.php?entry=entry090820-1224072009-08-20T00:00:00Z2009-08-20T00:00:00ZFlapping wing micro-UAV from AeroVironmentvideo on YouTube, and a short description of the recent milestone.
This is probably the work of micro-RC pioneer Matt Keenon, who works at AeroVironment.
]]>http://www.lecun.org/blog/index.php?entry=entry090716-2208402009-07-17T00:00:00Z2009-07-17T00:00:00ZStickduino now uses Atmega328Stickduino Arduino clone as been upgraded with the new Atmega328, so as to match the latest version of the "official" Arduino. The price is still below $20.
Strangely enough, the stickduino website makes no mention of the change!
How do I learned about it then?
Well, I just received a new batch of Stickduinos and tried to program one, but the program wouldn't upload (I kept getting "stk500_recv() programmer is not responding" from avrdude). I started looking on the web for answers, but couldn't find anything. After fiddling for a while, I looked closely at the board, and realized it had an Atmega328. I configured the Arduino IDE for the new Duemilanove Arduino, and everything worked perfectly.
Still, I'm surprised the stickduino people don't mention this anywhere. ]]>http://www.lecun.org/blog/index.php?entry=entry090715-0010212009-07-15T00:00:00Z2009-07-15T00:00:00ZJoel Frahm the QuotemasterJoel Frahm was playing his regular Tuesday-night gig at La Lanterna in NYC this week, accompanied by Bill Campbell at the drums (as usual), and Johannes Weidenmuller at the bass (replacing Joe Martin). Joel is something of a "quotemaster": his solos are often peppered with snippets from all kinds of things from other jazz pieces, classical music, pop music, and just about anything under the sun.
This Tuesday, Joel was in a particularly playful mood, and his high-flying solos brought an unusally rich harvest of detectable/delectable quotes including such things as Peter and the Wolf, Michel Legrand's "Les moulins de mon cœur" (Windmills of my mind), and (that's got to be a first) a theme from Star Wars!
Over the last 3 months, photographer Jimmy Katz has come to 8 or 10 of Joel's trio sessions at La Lanterna, equipped with a compact digital multi-track recorder. Each session he recorded has about 3 hours of music. Hopefully, these will soom be distilled and made available.
By ze way, the complete collection of Joel's sessions at Small's are available for on-line listening here.]]>http://www.lecun.org/blog/index.php?entry=entry090611-1732182009-06-11T00:00:00Z2009-06-11T00:00:00ZHuuuge collection of 3 viewspositively gigantic collection of airplane 3 views at rcgroups.
They even have one of my favorites: the obscure the coleoptere. ]]>http://www.lecun.org/blog/index.php?entry=entry090606-1609442009-06-06T00:00:00Z2009-06-06T00:00:00Zcyclogyro The cyclogyro has two rotating sets of "paddles" whose angle of attack is cyclically modified to create lift in the desired direction. The principle is well described by the animation in this Wikipedia article.
There is a YouTube video of a thethered micro-size cyclogyro, which was designed at the National University of Singapore. A detailed description of the design is available here.
A team of Japanese roboticists has apparently revived the concept, using a "pantograph" mechanism to vary the angle of attack (link to IEEE Tans. Mechatronics article), and a short description with pictures on PhysOrg.
I'm somewhat doubtful of the efficiency of the design, but it looks like a fun thing to build.
There is a number of article on the web that describe 1930's designs for cyclogyros. I am somewhat surprised that none of these designs seem to include an anti-torque system. These paddles are bound to generate a high torque that would make the vehicle pitch up (which is why the cyclogyro on the YouTube video has a propeller in the back).
]]>http://www.lecun.org/blog/index.php?entry=entry090514-1906512009-05-14T00:00:00Z2009-05-14T00:00:00ZRovio robots play soccer at NYUIntroduction to Robotics. The first series of assignments included programming Arduinos to read sensors and actuate servos and DC motors. The second series included programming a Pololu 3Pi robot to follow a line (using a PID controller), and perform dead reckoning (coming home after following a line to its end).
The Rovio robots can be seen as "Wifi webcams on wheels". The goal of the project was to push a tennis ball into a goal. The tennis ball is bright yellow, and the goal posts are red. The rovios are controlled by software running on a laptop which performs the vision and control algorithms. The software is written in our very own Lush language, which is a dialect of Lisp. ]]>http://www.lecun.org/blog/index.php?entry=entry090507-2339442009-05-08T00:00:00Z2009-05-08T00:00:00ZBill McHenry at La LanternaBill McHenry was sitting in for Joel Frahm, with bassist Joe Martin and drummer Bill Campbell. They played two of Bill McHenry's new compositions "Violetta" and "Lines" which I thought were particularly interesting. ]]>http://www.lecun.org/blog/index.php?entry=entry090401-0057102009-04-01T00:00:00Z2009-04-01T00:00:00ZmicRo CNC kitmicRo CNC kit for $500 for a partial kit and $1000 for a complete kit. You can also get a low-end Dell PC to control the CNC machine for $330, pre-configured with Ubuntu. The total travel dimensions are 34cm x 25cm x 8.9 cm.