This guy takes a drink and so does the virtual wooden mannequin. Well, its arm takes a drink because that’s all the researchers implemented during this summer project. But the demo really makes us think that suits full of IMU boards are the next generation of motion capture. Not because this is the first time we’ve seen it (the idea has been floating around for a couple of years) but because the sensor chips have gained incredible precision while dropping to bargain basement prices. We can pretty much thank the smartphone industry for that, right?
Check out the test subject’s wrist. That’s an elastic bandage which holds the board in place. There’s another one on this upper arm that is obscured by his shirt sleeve. The two of these are enough to provide accurate position feedback in order to make the virtual model move. In this case the sensor data is streamed to a computer over Bluetooth where a Processing script maps it to the virtual model. But we’ve seen similar 9-axis sensors in projects like this BeagleBone sensor cape. It makes us think it would be easy to have an embedded system like that on the back of a suit which collects data from sensor boards all over the test subject’s body.
Oh who are we kidding? [James Cameron’s] probably already been using this for years.
Continue reading “IMU boards as next-gen motion capture suit?”
[Chris Gammell] tipped us off that he’s building an online training program for learning electronics. The ten session course will cost money to take but you can get the goods for free if you’re one of the beta testers. We love to listen to The Amp Hour podcast which is just one of [Chris’] many endeavors.
Did you buy a Chromecast this week? We did, but we don’t have it in hand yet (ordered through Amazon). You can still get a look inside from the iFixit teardown.
Practice your Processing skills by using it to code a game of Pong.
A bit of lighter fluid and a hacked insert will get you a flaming wallet. We guess this is a different type of an anti-pickpocket device. [Thanks Stephen]
[Brain] used a $1.50 magnifying lens to help his Raspberry Pi camera module read QR codes better.
We really like [Aaron Christophel’s] LED matrix clock (translated). He started from a marquee that must be at least a decade old. He stripped it down and figured out how to drive it using a Sanguino as a controller.
[Kemper Smith] built a little piece of nature in Processing. He was inspired by a biology experiment that excited squid cells using electricity. The result is an interactive display that mimics that biology.
Last August we saw a peculiar experiment that forced Cyprus Hill music on the color changing cells of a squid. The cells make colors by stretching sacs of pigment; the larger they get the more of that color is shown. Normally this is used for camouflage. The image on the left is the reaction from connecting headphone wires while music is being played.
But we can’t all get our hands on this type of wet-ware — especially if life far inland. So [Kemper] got to work writing some Processing code. The result is seen on the right. It does a good job of replicating the motion and color palette of the original. He’s put together a web-based demonstration which you can interact with using your mouse cursor. But we also saw him demonstrate a Kinect based version at our local hackerspace.
Continue reading “Modeling squid cells in code foregoes connecting voltage to animals”
This is a working record created with a 3D printer. [Amanda] came up with a process that converts audio files into 3D models. These models can be printed and played on a standard record player.
The real work is done by a Processing sketch that creates a STL file. [Amanda] started off by trying to create a sine wave. She used this test to optimize the printing process. Then she used Python to extract audio data from WAV files and modified the processing script to process the data. After more tweaking, she was able to get a reasonable signal to noise ratio and minimize distortion.
The resulting records have a sample rate of 11 kHz and 5-6 bit resolution. The sound quality isn’t going to be the same as commercially pressed vinyl, but you can still make out the song.
A Objet Connex 500 was used to print the records. This UV printer has a 600 dpi resolution, which is means it’s more accurate than extrusion printers. Your mileage may vary using different printers, but all of the Processing and Python code is available with the project write up.
After the break, watch [Amanda] spin some 3D printed records.
Continue reading “3D Printing Records”
To be honest, we’ve heard of dithering but that’s the extent of our knowledge on the topic. After looking through [Windell’s] post about using Dithering in Processing we can now say we’ve got a base of knowledge on the topic.
Dithering is used to produce an image out of two colors that our eyes can put together into something meaningful. The history of the algorithms goes back to monochrome displays. But now the hobby electronics we work with for fun have comparable computing power and perhaps it’s time to rediscover these techniques. [Windell’s] project implements the Atkinson dithering algorithm in real-time on your webcam. He’s doing this in Processing, which should make it pretty easy to port for your own purposes.
So why might you want to use dithering in your own projects? Because if it can be used to make very cool milled artwork there must be other undiscovered uses lurking around your workshop.
Even with the added hardware that lamp still looks relatively normal. But its behavior is more than remarkable. The lamp interacts with people in an incredibly lifelike way. This is of course inspired by the lamp from Pixar’s Luxo Jr. short film. But there’s a little bit of most useless machine added just for fun. If you try to shut it off the lamp shade is used to flip that switch on the base back on.
[Shanshan Zhou], [Adam Ben-Dror], and [Joss Doggett] developed the little robot as a class project at the Victoria University of Wellington. It uses six servo motors driven by an Arduino to give the inanimate object the ability to move as if it’s alive. There is no light in the lamp as the bulb has been replaced by a webcam. The image is monitored using OpenCV to include face tracking as one of the behaviors. All of the animations are procedural, making use of Processing to convey movement instructions to the Arduino board.
Do not miss seeing the video embedded after the break.
Continue reading “Pixar-style lamp project is a huge animatronics win”
[Anilm3] wrote in to share the IMU tutorial series he is working on. An Inertial Measurement Unit is most often found in self-balancing robots and quadcopters, providing enough high-speed sensor data to keep up with the effects of gravity. He previously used some all-in-one IMU devices in school which did most of the work for him. But he wanted to grind down and look at what each sensor spits out and how those measurements are used. The first installment deals with the accelerometer, using its data to calculate pitch and roll. For these demonstrations [Anilm3] is using this ADXL345 sensor board, an Arduino, and some processing sketches for testing.
Whenever working with sensors you need to take noise into consideration. The post shows how to implement a low-pass filter in the code which will help smooth out the readings. The filtered data is then fed to a couple of mostly-painless formulas which calculate the movement of the accelerometer in degrees. The demonstration sketch is mapped to a 3D cube to give you an idea of how accurate the accelerometer is. There’s a little bit of lag which would let a self-balancing robot have a nasty fall. The solution to this issue will be discussed in upcoming parts of the series. The next installment tackles the gyroscope sensor.
Continue reading “Tutorial explains the concepts behind an IMU”