Dec 292012


3D Printed Record

In an effort to boldly 3D print where no man or woman has 3D printed before, I’ve created a technique for converting digital audio files into 3D-printable, 33rpm records and printed a few functional prototypes.  These records play on ordinary turntables with regular needles, just like any vinyl record.  Though the audio quality is low -the records have a sampling rate of 11kHz (a quarter of typical mp3 audio) and 5-6 bit resolution (less than one thousandth of typical 16 bit resolution)- the songs are still easily recognizable, watch the video above to hear what the records sound like.

This past year I’ve been posting a lot of audio projects, specifically, I’ve been experimenting with using relatively simple tools and techniques and very little memory to approximate and recreate digital audio signals.  A great example is my Arduino Vocal Effects Box, where I used an Arduino to perform realtime pitch-bending on an incoming audio signal.  Through these projects, I’ve learned that audio is a very resilient medium, it can take a fair amount of abuse (in the form of distortion and compression) while still maintaining most of the integrity of the original sound.  I’ve learned that as long as you loosely approximate the overall shape of an audio signal, the output will sound reasonably recognizable.  We have evolution to thank for this: as we hear audio, some complicated processing goes on in our brains that makes us very good at ignoring noise and focusing on the important pieces of information coming through.  We can work off of relatively few cues (sometimes these even include contextual or visual cues) to piece together mangled or noisy audio and make sense of it.  This is how we are able to focus on one voice in crowded room or decipher a message sent over a cheap walkie talkie.

This project was my first experiment extending this idea beyond electronics.  I printed these records on a UV-cured resin printer called the Objet Connex500.  Like most 3D printers, the Objet creates an object by depositing material layer by layer until the final form is achieved.  This printer has incredibly high resolution: 600dpi in the x and y axes and 16 microns in the z axis, some of the highest resolution possible with 3D printing at the moment.   Despite all its precision, the Objet is still at least an order of magnitude or two away from the resolution of a real vinyl record.  When I first started this project, I wasn’t sure that the resolution of the Objet would be enough to reproduce audio, but I hoped that I might produce something recognizable by approximating the groove shape as accurately as possible with the tools I had.

In this Instructable, I’ll demonstrate how I developed a workflow that can convert any audio file, of virtually any format, into a 3D model of a record and how I optimized these records for playback on a real turntable.  The 3D modeling in this project was far too complex for traditional drafting-style CAD techniques, so I wrote an program to do this conversion automatically.  It works by importing raw audio data, performing some calculations to generate the geometry of a record, and eventually exporting this geometry straight to a 3D printable file format.  Most of the heavy lifting is done by Processing, an open source programming environment that’s often used for 2D and 3D graphics and modeling applications.  Here’s a basic overview of my Processing algorithm:

use raw audio data to set the groove depth– parse through the raw audio data, this is the set of numbers that defines the shape of the audio waveform, and use this information to set the height of the bottom of a spiral groove.  This way, when a turntable stylus moves along the groove it will move vertically in the same path as the original waveform and recreate the original audio signal.
draw record and groove geometry– A 3D model is essentially a list of triangles arranged in 3D space to create a continuous mesh, use the data from the last step and some general record parameters (record diameter, thickness, groove width, etc) to generate the list of triangular faces that describes the record’s shape and the detailed spiral groove inscribed on its surface.
export model in STL format– the STL file format is understood by all 3D printers, export the geometry calculated in the last step as an STL file.  To get Processing to export straight to STL, I used the ModelBuilder Library written by Marius Watz (if you are into Arduino/Processing and 3D printing I highly recommend checking this out, it works great).

I’ve uploaded some of my complete record models to the 123D gallery as well as the Pirate Bay.  Check Step 6 for a complete listing of what’s there and what I plan on posting.  Alternatively, you can go to Step 7 to download my code and learn how to make printable record models from your own audio.

Special thanks to Randy Sarafan, Steve Delaire, Arthur Harsuvanakit, Phil Seaton, and Audrey Love for their help with this project.

Here’s another video that gives a great overview of the printing process and shows the printers at work:

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How Does a Record Work?

The basic mechanism of a record player is very simple.  The record moves at a constant rotational speed (usually 33.3 or 45 rpm) and a needle (also called a stylus) moves along a long spiral groove cut into the record’s surface.  As the record spins, the needle hits tiny bumps in the groove and vibrates to produce audio signals.  I won’t get into the specifics of how the needle extracts data from the record, but it is really interesting and there’s a great demo of it here.The record player and record cutter were invented by Edison in 1877.  Due to a lack of precise machinery and technique at the time, the grooves on the first records were much larger than those on modern microgroove records and, subsequently, the audio signals were much noisier.  This is a similar situation that I found myself in when starting this project: despite the high precision of the Objet machines, the resolution is nowhere near modern vinyl quality.  Here and here are two examples of Edison’s first phonograph tests.  You can hear that the quality of recording of these tests is pretty close to what I’ve been able to 3d print; although I can’t find the exact specs on these records, I’d imagine that the scale of the grooves was similar to what I was working with.To give you an idea of the resolution of a modern record, check out the images above.  Figs 1-3 are from Chris Supranowitz, a researcher at The Institute of Optics at the University of Rochester.  These are close up images of a vinyl record, taken with an electron microscope.  The dark objects in figs 1 and 2 are tiny particles of dust.  Fig 3 is a bird’s eye view of the record grooves, the darker regions are the top (uncut) surface of the record.

Fig 4 was made by branku62 at, it shows the profile dimensions of a standard microgrove mono groove, this is what you would find on a modern mono 33 or 45 (stereo grooves are actually cut a bit smaller).  In the diagram 1 mil = 1/1000″, which is about 25um.  Microgroove records require a stylus with a 0.7 to 1.0 mil radius tip, the tip makes contact with the groove at E in fig 1, a width of about 1.4 mil.  The total depth of the groove is around 1.1 mil.  These dimensions match up nicely with the dimensions of the electron microscope images.

Fig 5 is from Ron Geesin and Mark Berresford’s website, it shows the groove depths of the older 78’s.  These records were much more coarse than microgroove records, both the needle and grooves were about 3x as large in every dimension.  Fig 2 shows the groove depth for 78’s was somewhere between 2.2 and 3.6 mil.  The stylus radius was around 2.7 mil.

1-40 of 145 Next »

ysatoh says: Dec 27, 2012. 7:51 PMReply

mukelarvin says: Dec 27, 2012. 6:41 AMReply
I’m so glad to see someone follow through on this concept. I investigated it a little bit back when I was doing my thesis project but I couldn’t pull it off.It’s cruel but I really like imagining the pain on the face of an “audiophile” when you tell them you printed a record from a compressed mp3.

thassaj says: Dec 25, 2012. 11:36 AMReply
Amanda this is genius! The ability to come up with ideas like this is rare – you should aim very high in your future career.

McM-Chriis says: Dec 25, 2012. 7:39 AMReply
You Are a sensation on Internet WEBs!!! You Discover that !!! lol

masynmachien says: Dec 21, 2012. 6:19 AMReply
Truly epic!I was thinking, for a higher mechanical resolution, you could use the rapid prototyping machines as used in photonica labs (e.g. high precision milling).

amandaghassaei (author) says: Dec 21, 2012. 11:33 AMReply
there’s talk of that, I’m going to start with a laser cutter, but I’m interested in a milling option too

masynmachien says: Dec 25, 2012. 5:48 AMReply
Yes, laser cutting sounds like an interesting approach. It is probably more accessible than milling with very small cutting tools.

TheRealDutchOwner says: Dec 25, 2012. 5:20 AMReply
A while back, I actually thought about this concept, 3D printing records. Nice to see that other people do aswell and even go ahead and realize that.

dlebryk says: Dec 20, 2012. 7:28 PMReply
Amanda – Beautifully done, well researched, great approach.It might help if you did the recordings in 45RPM. For a given wavelength reproduced, a 45RPM track is longer (ability to pack in more information given the resolution limit you have with the printer) versus a 33RPM track. Most every turntable around will run at 45RPM (you are correct 78RPM is hard to find) – move the belt to the other pulley or flip the switch. A lot of vinyl albums are pressed at 45RPM now – they are theoretically higher fidelity.The longer length would allow you to use a higher resolution sound file. The RIAA curve would help a little bit, but it wouldn’t be as dramatic as increasing to a higher resolution file.

amandaghassaei (author) says: Dec 20, 2012. 11:47 PMReply
yeah I talked about this a little in step 2. I plan on trying it out, I’m sure it will sound better, I have some files scaled to 45rpm, but haven’t had the time to print them yet

dutado says: Dec 23, 2012. 1:16 PMReply
With 3000rpm, dithering and low pass filter, you could achieve a few seconds of studio quality sound 🙂
Good work, great idea.

dutado says: Dec 23, 2012. 1:16 PMReply
With 3000rpm, dithering and low pass filter, you could achieve a few seconds of studio quality sound 🙂
Good work, great idea.

Grasshopper1221 says: Dec 23, 2012. 6:12 AMReply
Gratz you have made national headlines!

amandaghassaei (author) says: Dec 23, 2012. 8:56 AMReply
Nice thanks for the link! Getting kind of tired of being referred to as “he” but whatever…..

mariuswatz says: Dec 22, 2012. 3:05 PMReply
I’m very happy to see such a great use of my Modelbuilder library! I’m currently updating it for Processing 2.0, will post it on GitHub very soon:

amandaghassaei (author) says: Dec 22, 2012. 9:05 PMReply
glad you liked it, thanks again for posting the library!

Dithermaster says: Dec 22, 2012. 3:56 PMReply
This is really awesome.BTW, the process of turning up the gain without clipping is called “compression” or “companding” and you should use it instead of just turning up the gain and then clipping. You can use a Volume Maximizer plug-in or a compressor followed by a limiter. See and, awesome! My MakerBot has some catching up to do.

amandaghassaei (author) says: Dec 22, 2012. 9:04 PMReply
cool, I’ll try that

Jan.H says: Dec 22, 2012. 3:32 AMReply
And for proper RIAA equalization, before amplifying the recording in Audacity in step 7, go to Effects>Equalization. Then, from the “Select Curve” list box, select the RIAA preset, and afterwards, hit the “Invert” button, because you want to create a new record (with bass attenuated, and high frequencies boosted), while Audacity’s preset is intended for playback.

GarthBock says: Dec 21, 2012. 10:35 PMReply
To GrfxGawd:Uh…this was a joke…you know….something that requires a sense of humor…..there’s an instructable on that..

kweinberg says: Dec 21, 2012. 8:08 PMReply
Very cool!!

RDalenberg says: Dec 21, 2012. 2:12 PMReply
Excellent documentation. I can see your work being applied to the surface texture of other printed objects. Have you considered using a laser to READ the texture? I imagine a cheep laser scanner reading an object with printed 2d barcodes and audio data embedded in the surface texture.

daveclark5 says: Dec 21, 2012. 1:03 PMReply
I have an ancient edison dictaphone which used the wax cylinders. The thing about Edisons solution is that when one was done with dictation the cylinder could be scraped flat with a primitive lathe.I think your project concept is excellent. You’d probably achieve higher fidelity by cutting a pre-formed with an inscribing tool (basically a 3D milling machine instead of 3d printing. cutting plastic than printing.Perhaps by combining some precision robotics controllers, stepper motors, etc you could learn to cut plastic. This would be great for all types of users with 3D printers who want to take a second pass at the printed output and put a slot or grove or hole in it.

excellent concept – good luck!

edison wax cylinders.jpg

amandaghassaei (author) says: Dec 21, 2012. 1:42 PMReply
very cool, yes I’m going to cut another record on acrylic with a laser cutter soon

madshobye says: Dec 21, 2012. 1:03 PMReply
Love it!

amandaghassaei (author) says: Dec 21, 2012. 1:41 PMReply

baltika says: Dec 21, 2012. 2:38 AMReply
What if you could use a radial printer (assuming one was available)?

amandaghassaei (author) says: Dec 21, 2012. 11:31 AMReply
yes that would lower the noise in my signal for sure. The objet rasters each layer in, but getting some kind of vector printer would be great.

spange says: Dec 21, 2012. 7:40 AMReply
I was thinking that if you could get the printer to print from the center out in a spiral motion, it might fix the sine wave problem. Might even get more fidelity out of it too.

lebeno says: Dec 21, 2012. 8:04 AMReply
Did you perform an RIAA correction on the audio beforehand? That would lower the intensity of the base and pull up the high end. The record player does the reverse of this, Read more on

amandaghassaei (author) says: Dec 21, 2012. 11:30 AMReply
I didn’t, lot’s of people have suggested this, i think you’re right, it would help to balance the signal out a bit

RC_tech says: Dec 21, 2012. 9:20 AMReply
Great idea, printing vinyls with a 3D printer! Hope you’ll enhance the quality!For now a tip: Try C64 tunes or other chiptunes for experimenting. Although the soundchip SID is a synthesizer, it is able to play digitalized sounds from about 5 to 6 bits, ideal for experimenting with your printed vinyls.

There is also a special cardridge for the C64, the MSSIAH. It’s an all-in-one audio cardrigde which also allows to play MIDI-controlled samples in 6 bit. There’s a big forum with musicians, maybe some people are even interested to get their tunes on printed vinyl 😉

Or try some of the over 42.000 SID songs from the High Voltage SID Collection 😉

Greets, RC.

amandaghassaei (author) says: Dec 21, 2012. 11:30 AMReply
I’ll look into it thanks!

ledzurso says: Dec 21, 2012. 11:04 AMReply
It sounds like I’m on hold

zigzagchris says: Dec 21, 2012. 7:07 AMReply
I think your at the beginning of something great, good luck. Vinyls rock!!

FrankinAround says: Dec 21, 2012. 6:43 AMReply
you are a super hero.

Laia_bee says: Dec 21, 2012. 3:42 AMReply
I´m a dj and vynils are so expensive, this could change the future of the vynil industry! I really hope you succeed!! are you into kickstarter?

ahaase1 says: Dec 21, 2012. 3:03 AMReply
Very fascinating idea to print my own records

jeikmauf13 says: Dec 20, 2012. 5:25 PMReply
What if you were to use a laser engraver to cut on acrylic or a similar material?

amandaghassaei (author) says: Dec 20, 2012. 11:49 PMReply
already in the works! check back in january, I should have it posted soon.
1-40 of 145 Next »

 Posted by at 5:55 am
Dec 292012

Supersymmetry: is it really too good not to be true?

Supersymmetry is a beautiful theory that might explain dark matter – now particle physicists at Cern are putting it to the ultimate test

part of the Large hadron Collider<br />

Part of the Large Hadron Collider at Cern. Photograph: Peter Ginter/CERN

The origin of dark matter remains a mystery. It is thought to dominate the mass of the universe and the evidence is very hard to refute. Probably the best candidate for an explanation is an idea known as supersymmetry. Physicists like to exploit symmetry to build their theories. For example, that it does not matter if I perform an experiment today or next week (all things being equal) constitutes a statement of symmetry and, impressively enough, it leads directly to the law of energy conservation.

Supersymmetry is harder to visualise but its implications are not. It demands that for every type of elementary particle there should be a would-be twin. This means that the mere existence of electrons implies that supersymmetric electrons should also exist (they are called “selectrons”). I said “would-be twin” because if supersymmetry were a perfect symmetry, the electron and the selectron would have the same mass, but experiments over many years have established that this is not the case.

The upshot is that if supersymmetry is realised in nature then it must also be “broken” to some degree, with the result that the super-particles should all be heavier than the twins we have already seen. This does sound contrived; we have introduced a symmetry and then found we need to break it to hide the embarrassing extra particles that it predicts. But broken symmetry is the norm and often occurs when systems cool down. For example, at high enough temperatures, water molecules are free to move around in all directions, but as the air cools they freeze together and produce those beautiful patterns we see on an icy cold window pane. In this case, the “all directions” symmetry is broken to the diminished symmetry embodied in the pattern on the window. So it is to be expected that supersymmetry is not readily apparent in the relative coldness of our experiments. As a bonus, the fact that all those super-particles should be heavy compared to the common-or-garden particles produced daily at Cern turns out to be a direct consequence of broken symmetry – and so supersymmetry is not so contrived after all. The fact that one of those super-particles has all the characteristics needed of dark matter is an attractive bonus.

Supersymmetry was not invented to explain dark matter. It sits alongside curved spacetime as one of those beautiful ideas that seem simply too good not to be true. The beauty comes from the way that its extends the symmetries of space and time, as embodied in Einstein’s theories, so as to unify the different types of particle that can possibly exist. This unification is an essential ingredient of theories such as string theory. For many theoretical physicists, it is hard to believe that supersymmetry does not play a role somewhere in nature. The big question is whether its influence is confined only to the very earliest moments of the universe; moments that lie outside of the reach even of the Large Hadron Collider (LHC). We are encouraged to suppose that this is not the case and that super-particles might show up soon not only because that is what the dark matter explanation would suggest but because it also provides an explanation for why the Higgs particle should be as light as it seems to be.

So what of the evidence? Prior to the LHC turning on, there was no shortage of optimism that super-particles might be produced in abundance and that we would be celebrating their discovery by now, but that has not proved to be the case. The latest news in the search for supersymmetry was presented at the recent Hadron Collider symposium in Kyoto from which the BBC reported a result presented by the LHC Beauty collaboration (LHCb for short) as representing a “significant blow” to supersymmetry. So what did they measure and what does it imply?

The rough-and-ready way to discover supersymmetry at the LHC is to smash protons into each other and scan the debris for traces that a super-particle was produced. So long as the new particles aren’t too heavy, they ought to show up at some point in the lifetime of the LHC. But there is another way to tease out supersymmetry: one can look for its influence indirectly.

Super-particles ought to have an impact on quantities that the LHCb experimenters are measuring even though they might actually be too heavy to be produced. This is a clever idea – it exploits Heisenberg’s Uncertainty Principle, which allows for energy to be borrowed from empty space but only for a fleeting instant, after which it needs to be returned again. In that moment, it is possible to create a super-particle. The trace that this has happened is usually too small to measure, a tiny ripple in an ocean of waves. But this is where the LHCb comes in. The experimenters have been studying the fate of the beauty meson (or B-meson for short). B-mesons are produced prolifically and the LHCb experiment is set up to study them with high precision. The B-meson particles of interest don’t hang around for too long; within around one picosecond, they “decay” into lighter particles and those super-particles produce a ripple too feeble to be detected. However, there are very rare cases where the mesons do not decay in the usual way. One case was predicted to be so rare as to be almost disallowed by established physics. This is when the meson decays and, in its death throes, produces a pair of muons (a heavy version of the electron). This should occur around three times for every billion mesons produced. This extreme rarity means there is an opportunity for the tiny super-particle effect to manifest itself in a measurable way – it is like the ocean waves have been stilled, making the ripples easier to spot. All that is needed is for the experimenters to identify the decay and count how often it happens. If it happens too often (or too infrequently), then we can start to get excited. The bottom line is that the experimenters have made the measurement – they have counted those thrice-in-a-billion decays and found perfect agreement with the standard theory, with no trace of any super-particles (or any other new particles for that matter).

So where does that leave supersymmetry? The LHCb measurement, combined with other measurements from the LHC, helps to cut down the possibilities but the data remain very far from ruling out supersymmetry. Until the LHC turned on, there was much theoretical speculation and this is being whittled down. This is what the LHC was built to do and it will either discover supersymmetry and confirm its prediction for dark matter or it will exclude it to the point whereby many of its attractive features are lost. Supersymmetry is too broad an idea to be entirely excluded by the LHC, but its specific instances are progressively falling by the wayside. As ever in science, we need to be patient.

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Dec 282012

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 Posted by at 7:43 pm
Dec 222012



Two days in New York


2 Days In New York


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  • Genre: Comedy
  • Released: 2012
  • © 2012 Polaris Film Production & Finance, Senator Film, Saga Film, Tempête sous un Crâne Production, Alvy Productions, In Production, TDY Filmproduktion – All rights reserved.



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A visit from relatives overseas disrupts a New York couple’s home life and initiates two unforgettable days of family mayhem.
  • Starring: Chris Rock, Julie Delpy
  • Directed by: Julie Delpy
  • Runtime: 1 hour 36 minutes
  • Release year: 2012
  • Studio: Magnolia Pictures
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 Posted by at 10:32 am
Dec 162012

3p4w clock

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[Oct 16, 2012] 3p4w-clk20.c uploaded, to support launchpad v1.5 20pin devices
  • migrate to v1.5 lauchpad, provide alternate layout for 20pin devices
  • comment / uncomment #define DEVICE_20P for 14pin and 20pin devices
  • tried w/ msp430g2452
  • linux build observe changes in mspgcc, i.e. #include <legacymsp430.h>, etc
  • now autodect 32khz crystal, if present, will provide much more accurate time
 Posted by at 10:02 am
Dec 152012

Wednesday, November 28, 2012

Stellaris Launchpad MOD Player

It is time for a new post!
Recently I got myself a Stellaris Launchpad board by TI and thought what I could do with it.
I decided to create a simple MOD player with the bear minimum of extra parts and so here is the

The details:
The code I’ve ported from a Microchip pic32 MIPS based MCU that was done here by SERVEURPERSO:

Had to redo all the PWM/Timers/Buttons/File system and other stuff.
Learned a lot from the PWM tutorial for Stellaris here:

The video recording was done using PC LINE IN and in stereo and because of that there is a faint whine in the background but the sound that comes directly from the board is much better.

The board supports only 4 channel MODs technically you can put a MOD with more channels but there is no memory allocated for them, so the results are unpredictable.
There is enough space on the device for 213Kb of MODs.
Right now the code is set to take up-to 6 MODS, you can change it if you want (as long as you keep below the 213Kb limit)

Because I did not have an SD card breakout board I had to load the files from somewhere
so I’ve created VFS (Virtual File System) which helped a lot during development, the files reside inside the
flash of the MCU.
It should be fairly easy to switch to FatFs since I’ve used the same prototype functions.

SD support will probably come in the future (when I get a SD breakout board)

Technical difficulties:
While porting this I’ve encountered several difficulties:
1. The amount of RAM on the pic32 device was 3 times what we had (96K vs our 32K)
had to shrink the buffers a lot, will see how it affects while reading from SD card.
2. PWM code completely different, had to understand both architectures and settings to rewrite
it correctly.
3. Timing for the sampler interrupt is CRITICAL even a small difference in invocation
would cause popping and beeping in sound.
4. Interrupt priorities, after adding the buttons handling (which are polled using the systick interrupt) I’ve       noticed that the sound would be distorted, which I’ve concluded was due to the sampler interrupt not getting enough time to run or was itself was being interrupted, a code to set priorities to interrupts was added.

1 x Stellaris Launchpad
1 x Audio Jack

Take the audio jack connect the GND pin to the GND pin on the board J3.2
LEFT channel is J1.7 (PB4)
RIGHT channel is J2.7 (PB6)

Right button next song
Left button previous song.

If connected to computer the serial terminal writes some info about the song that is playing.

Attached is the whole project, source, binary and convert tool for mods.
Download project.

To use the convert tool: after extracting the project to Stellarisware directory.
NOTICE: My Stellarisware directory is called Stellarisware2 so some adjustments might be necessary in order to compile the sources, the project should be placed next to the other projects:

go into the tools directory copy all your wanted MODS to that dir and run “runconvert.bat”

To get more mods go to:

Hope that helps anybody.


  1. Congrats, this is really an awesome project!

    Some of your mods sound like FM synthesis.


  2. They are called chiptunes (because they sound like commodore 64 SID chips) I’ve chosen them because of their small size.

  3. Can I make an assumption that this will not work with the msp430 value line Launchpad?


  4. Trevor, your assumption is correct.

    The stellaris launchpad is an ARM device
    the msp430 is a 16-bit architecture that is much weaker.

  5. Thanks! After watching this I want to get myself one of these now…. even though it took me the better part of a year to pull my msp launchpad out of the drawer to do something with it!

    Thanks for sharing this project, it was very cool!

  6. I can confirm that this works; I have two Stellaris Launchpads and I just tested. Sound quality is great, but consider adding a filter cap from each PWM output to ground to reduce the high frequency from the PWM.


  7. You could use the MSP430 Launchpad breakout. I’m not sure how you would handle the dual row issue though.


  8. Thanks for the info, but I’m going to use just some chep
    1.6$ SD breakout board and a bunch of jumper cables.

    Maybe make it backward compatible with this shield though.

  9. Just got this working … sounds great!

    If  you installed the stellarisware to the default location like I did then you need to edit the .project and .cproject files and change all references to “stellarisware2” to “stellarisware” in a text editor before importing the project into your workspace.


  10. Works great “as is”, I have just uploaded .bin file in Launchpad. Can’t wait for SD card support for unlimited music ^_^


  11. Nice!
    Chiptunes will never die.




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 Posted by at 2:42 pm
Dec 152012



Get started with the LaunchPad Evaluation kit from Texas Instruments

Get started with the LaunchPad evaluation platform from Texas Instruments. LaunchPad kits are available for TI’s complete line of microcontrollers, including MSP430™, C2000™, and Stellaris® ARM® Cortex™-M4. These low-cost kits provide developers with everything they need to start designing new applications.


  • MSP430 LaunchPad
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  • Stellaris LaunchPad

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 Posted by at 2:28 pm
Dec 152012

Commercial Version of the MIT Media Lab CityCar Unveiled at European Union Commission Headquarters

A full-scale version of the stackable, electric CityCar, created by researchers at the MIT Media Lab and commercialized by a consortium of automotive suppliers in the Basque region of Spain, was unveiled at the European Union Commission headquarters on January 24, 2012.

Branded “Hiriko,” the vehicle incorporates all of the essential concepts of the MIT Media Lab CityCar: a folding chassis to occupy a small footprint when parked, drive-by-wire control, front entry and egress, the ability to spin on its axis, and “Robot Wheels” with integrated electric drive motor, steering motor, suspension, and braking. Since 2009, the Media Lab has collaborated with Denokinn, an industrial sponsor from Vitoria, Spain, and their partner companies to refine the design and technology of the CityCar to allow for its commercialization by industry.

The CityCar project is part of larger initiative at the MIT Media Lab devoted to investigating the urban mobility systems. Conceived by a team of MIT students led by the late Professor William J. Mitchell (1944-2010), the CityCar is a two-passenger EV that is capable of folding to minimize its parking footprint.

The design utilizes a novel technology called Robot Wheels. The Robot Wheel modules are controlled electronically using by-wire systems made popular by the aerospace industry and is attached to the four corners of the foldable chassis designed by the MIT team. Each Robot Wheel can be independently controlled allowing the CityCar to execute tight maneuvers that are helpful when driving in cities such as spinning on its own axis to achieve an “O-turn.” The removal of traditional drivetrain elements like gasoline engine, transmissions, and gearboxes allows for an unencumbered chassis thus freeing up space for folding linkages. When folded, three CityCars can fit into one traditional parking space, therefore making parking more efficient in dense crowded cities. The CityCar has a range of over 100km on one charge and is capable of being rapidly charged using the latest lithium-ion battery technologies developed by industry including spinout companies from MIT.

Mobility-on-Demand systems consisting of lightweight
electric vehicles designed by the MIT Media Lab’s
Smart Cities research group.

The CityCar compared to traditional automobiles.
 Posted by at 2:16 pm
Dec 152012

The portfolio of Chengyuan Wei.

Persuasive Electric Vehicle
Prof. Kent Larson
Ryan Chin
William Lark
Michael Chia-Liang Lin
Nicholas Pennycooke
Marcus Martinez
Chengyuan Wei

Changing Places Group,MIT Media Lab

The PEV is a new electric vehicle that simultaneously addresses the problem of congestion, pollution, obesity and aging, by taking advantage of existing bicycle lanes.

The PEV is a human-assist hybrid vehicle that incorporates pedal power generation, electric motors for drive, and batteries for energy storage. Users can pedal to generate electrical power that is stored in the battery, which in turn provides power to the electric motors in the wheels. Depending on your level of desired fitness you can generate as much or little energy as necessary. For example, an elderly woman can gently pedal but still get meaningful exercise when travelling, while a young athlete could generate enough energy to offset the energy spent from the battery.

The PEV will have 3 wheels for stability and a soft-cover made out of the latest smart fabrics for protection against the elements. It will also have the option for cooling and heating in extreme climates. These features along with the electric motor will lower the demographic barrier (typically young men in biker shorts) for use of this vehicle to the elderly, men in business suits, and women in skirts.

The PEV will be designed under the European Union’s rules for e-bikes including electric motor size (250watts), total weight (60Kgs), top speed (20KPH), etc.

Since the PEV is still a concept, Korean manufacturers will have the opportunity to fund this Cloud Mobility-on-Demand, Changing Places Group, MIT Media Lab 2011
 View the PDF with detailed process_Click here

The video introduction of PEV project and the initial design scheme.

The back seat concept and Sketchs

The concept illustrated by sketching is to pull down the back part of the main seat to change its function from a basket into an extra seat, meanwhile the shield which has collapsible structure will be relatively stretched to cover the expanded area.


Two versions of 1 to 6 model were made by using laser cut machine. These preliminary prototypes were used to explore factors of the windshield, joint connections between different shields, and the conceptual structure of steering system, etc.

3D Model Building

The second version 3d model improves the first version in term of simplifying the structure and adding more details such as handle, battery and pedal. General dimension of the vehicle basing on a preliminary drawing of Marcus Martinez who is also the desiger of the former scheme.


A simulation of materials application and the final effect of the vehicle.

3D model of the third version

William Lark, a PhD candidate of Changing Places group, helped to add the steering system and chain system into 3D model and made a significant change to the frame which makes the whole structure more reasonable and stable.
Based on Will’s editing the third version of 3D model and rendering pictures have been finished.

Modifications and Rendering pictures

Features have been modified:
‐ Adjusting structure for the main seat.
‐Redesign the back seat for both Baby and groceries   (collapsible structure).
‐Reinforce the spokes of front wheels.
‐Simplify the back part of the shell.



 Posted by at 2:13 pm
Dec 142012

What is love? Five theories on the greatest emotion of all

It’s the most popular search on Google – but what’s the answer? Experts in fields from science to fiction share their thoughts

A Bulgarian couple kiss in Sofia's central mall

Looking for answers in Sofia’s central mall, Bulgaria. Photograph: Valentina Petrova/AFP/Getty Images

“What is love” was the most searched phrase on Google in 2012, according to the company. In an attempt to get to the bottom of the question once and for all, the Guardian has gathered writers from the fields of science, psychotherapy, literature, religion and philosophy to give their definition of the much-pondered word.

The physicist: ‘Love is chemistry’

Jim Al-Khalili<br />
Jim Al-KhaliliJim Al-KhaliliBiologically, love is a powerful neurological condition like hunger or thirst, only more permanent. We talk about love being blind or unconditional, in the sense that we have no control over it. But then, that is not so surprising since love is basically chemistry. While lust is a temporary passionate sexual desire involving the increased release of chemicals such as testosterone and oestrogen, in true love, or attachment and bonding, the brain can release a whole set of chemicals: pheromones, dopamine, norepinephrine, serotonin, oxytocin and vasopressin. However, from an evolutionary perspective, love can be viewed as a survival tool – a mechanism we have evolved to promote long-term relationships, mutual defence and parental support of children and to promote feelings of safety and security.

• Jim Al-Khalili is a theoretical physicist and science writer

The psychotherapist: ‘Love has many guises’

Philippa PerryPhilippa PerryUnlike us, the ancients did not lump all the various emotions that we label “love” under the one word. They had several variations, including:

Philia which they saw as a deep but usually non-sexual intimacy between close friends and family members or as a deep bond forged by soldiers as they fought alongside each other in battle. Ludus describes a more playful affection found in fooling around or flirting. Pragma is the mature love that develops over a long period of time between long-term couples and involves actively practising goodwill, commitment, compromise and understanding. Agape is a more generalised love, it’s not about exclusivity but about love for all of humanity. Philautia is self love, which isn’t as selfish as it sounds. As Aristotle discovered and as any psychotherapist will tell you, in order to care for others you need to be able to care about yourself. Last, and probably least even though it causes the most trouble, eros is about sexual passion and desire. Unless it morphs into philia and/or pragma, eros will burn itself out.

Love is all of the above. But is it possibly unrealistic to expect to experience all six types with only one person. This is why family and community are important.

• Philippa Perry is a psychotherapist and author of Couch Fiction

The philosopher: ‘Love is a passionate commitment’

Julian BagginiJulian BagginiThe answer remains elusive in part because love is not one thing. Love for parents, partners, children, country, neighbour, God and so on all have different qualities. Each has its variants – blind, one-sided, tragic, steadfast, fickle, reciprocated, misguided, unconditional. At its best, however, all love is a kind a passionate commitment that we nurture and develop, even though it usually arrives in our lives unbidden. That’s why it is more than just a powerful feeling. Without the commitment, it is mere infatuation. Without the passion, it is mere dedication. Without nurturing, even the best can wither and die.

• Julian Baggini is a philosopher and writer

The romantic novelist: ‘Love drives all great stories’

JojoJojo MoyesWhat love is depends on where you are in relation to it. Secure in it, it can feel as mundane and necessary as air – you exist within it, almost unnoticing. Deprived of it, it can feel like an obsession; all consuming, a physical pain. Love is the driver for all great stories: not just romantic love, but the love of parent for child, for family, for country. It is the point before consummation of it that fascinates: what separates you from love, the obstacles that stand in its way. It is usually at those points that love is everything.

• Jojo Moyes is a two-time winner of the Romantic Novel of the Year award

The nun: ‘Love is free yet binds us’

Catherine WybourneCatherine WybourneLove is more easily experienced than defined. As a theological virtue, by which we love God above all things and our neighbours as ourselves for his sake, it seems remote until we encounter it enfleshed, so to say, in the life of another – in acts of kindness, generosity and self-sacrifice. Love’s the one thing that can never hurt anyone, although it may cost dearly. The paradox of love is that it is supremely free yet attaches us with bonds stronger than death. It cannot be bought or sold; there is nothing it cannot face; love is life’s greatest blessing.

• Catherine Wybourne is a Benedictine nun

 Posted by at 7:11 am
Dec 042012

Open access to 803,592 e-prints in Physics, Mathematics, Computer Science, Quantitative Biology, Quantitative Finance and Statistics

Subject search and browse:

19 Oct 2012: arXiv Holiday Schedule
29 Aug 2012: Simons Foundation funds new arXiv sustainability model
See cumulative “What’s New” pages. Read robots beware before attempting any automated download



Computer Science

Quantitative Biology

Quantitative Finance


About arXiv

 Posted by at 8:12 pm
Dec 042012

Saturday, December 1, 2012

Numeric CAS Part 2: Binomial Expansion

Binomial Expansion

Goal: To find the coefficients of when (ax + by)^n is expanded. The variables a and b are numeric.

(ax + by)^n = Σ (n nCr k *(ax)^(n-k) * (by)^k for k = 0 to n).

Example: (3x – 2y)^3 = 27 x^3 – 54 x^2 y + 36 x y^2 – 8 y^3

For the Casio Prizm and TI-84+, each coefficient is given in order. They are also stored in List 6. For the HP 39gii, a string is built representing the expanded binomial.

The list in the above example is {27, -54, 36, -8}

Casio Prizm:

Binary Expansion
216 bytes

Lbl 6
“A”?”→ A
“B”?→ B
“N”?→ N
If N≤0 Or Frac N≠0
Goto 6
For 0 → K To N
N nCr K × A ^ (N – K) × B ^ K → C
Locate 1,2,C
Locate 1,3,”×X^”
Locate 4,3,N-K
Locate 7,3,”×Y^”
Locate 10,3,K ◢
C→ List 1[K+1]


Binomial Expansion
177 bytes

: Lbl 1
: Disp “(AX+BY)^N”
: Prompt A,B,N
: If N≤0 or fPart(N)≠0
: Then
: Pause
: Goto 1
: End
: N+1->dim(L6)
: For(K,0,N)
: N nCr K*A^(N-K)*B^K->C
: ClrHome
: Output(2,1,C)
: Output(3,1,”*X^”)
: Output(3,4,N-K)
: Output(3,7,”*Y^”)
: Output(3,10,K)
: Pause
: C->L6(K+1)
: End

HP 39gii:

Polynomial Binomial Expansion
Expand (ax + by)^n

The results are returned in a string. Note, if N is not a positive integer, it is converted into one.


ABS(INT(N)) → N;
“” → S1;
string(COMB(N,K)*A^(N-K)*B^K) → S2;
S1 + “+” + S2 + “*X^” + string(N-K) + “*Y^” + string(K) → S1;
dim(S1) → K;
right(S1,K-1) → S1;

This blog is property of Edward Shore. 2012

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 Posted by at 7:10 am
Dec 042012

Home>Knowledge Base>WordPress>Customizing a WordPress Theme Based on Suffusion

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Article ID 20
Created On 11/6/2010
Modified 11/6/2010
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Customizing a WordPress Theme Based on Suffusion

Instructions for Customizing a WordPress Theme Based On SuffusionSuffusion is the most amazingly powerful WordPress theme we have ever discovered. The tremendous power of this theme is not so much that it gives you a look for your site, but rather a truly in-depth power to control a tremendous number of aspects of that look — right through the WordPress control panel. You can download the Suffusion theme here:

Here are the steps we use to customize a site theme based on Suffusion:

Step 1: Copy the Suffusion theme and rename this for the site; then log into the blog and set it to use this theme (you may have to activate Suffusion and then activate this new theme). For example, the the domain name for the site is, rename this copy of Suffusion to “MyDomain”.

Step 2: On the left side of the dash board, click on Suffusion and then Visual Effects. Find a theme that is relatively close to the style of the web site and select it.

Step 3: Visual Effects / Header Customization
Set the settings which are most appropriate for the design.

Step 4: Visual Effects / Theme Skinning
Set the settings which are most appropriate for the design.

Step 5: Visual Effects / Body Font Settings
Set the settings which are most appropriate for the design.

Step 6: Visual Effects / Footer Customization
Set the settings which are most appropriate for the design. Enter an XTML markup needed here.

Step 7: Visual Effects / Sizes and Margins
Set the settings which are most appropriate for the design.

Step 8: Visual Effects / Custom Emphasis Elements
Set the settings which are most appropriate for the design.

Step 9: Sidebars and Widgets
Set the settings which are most appropriate for the design.

Step 10: Blog Features
You may need to change some settings under Main Navigation Bar Setup

Step 11: Create custom override styles
Once the customization of the Suffusion theme has been styled this far, further styling may need to be done through an override style sheet. Under Blog Features in Suffusion, select the Custom Includes tab. In the field for First Additional Stylesheet Link, provide the fully qualified URL for a new style sheet called style-override.css. Make the path to this file be in the customized version of the Suffusion theme you set up above, for example

Step 12: Create whatever styles you need to override other inheriting styles in the theme in the stylesheet identified in Step 11.

Step 13: You will likely need to edit markup for the header. In Suffusion, the markup for the header is dynamic and stored in a function:
function suffusion_display_header()

Step 14: Similarly, while Suffusion does provide locations to enter markup for the footer regions (Visual Effects: Footer Customization), you may need to further edit the markup beyond these controls. Like the header, the footer is also dynamically generated through a function in Suffusion, which you will find here:
function suffusion_display_footer()

Using the Suffusion theme to configure steps 2-11, you should only need to edit two files: /blog-root/wp-content/themes/mytheme/functions/actions.php, and /blog-root/wp-content/themes/mytheme/style-custom.css.

 Posted by at 7:07 am
Dec 012012

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 Posted by at 6:52 pm