This is an older project, but the electromechanical solution used to create this giant, staring eyeball is worth a peek. [Richard] and [Anton] needed a big, unblinking eyeball that could look in any direction and their solution even provides an adjustable pupil and iris size. Making the pupil dilate or contract on demand is a really nice feature, as well.
The huge fabric sphere is lit from the inside with a light bulb at the center, and the iris and pupil mechanism orbit the bulb like parts of an orrery. By keeping the bulb in the center and orbiting the blue gel (for the iris) and the opaque disk (for the pupil) around the bulb, the eye can appear to gaze in different directions. By adjusting the distance of the disks from the bulb, the size of the iris and pupil can be changed.
A camera system picks out objects (like people) and directs the eye to gaze at them. The system is clever, but the implementation is not perfect. As you can see in the short video embedded below, detection of a person walking by lags badly. Also, there are oscillations present in the motion of the iris and pupil. Still, as a mechanism it’s a beauty.
Continue reading “Behold the Giant Eye’s Orrery-Like Iris and Pupil Mechanism”
[Koppany Horvarth] set out to create a dirt-cheap optical tracking rig for VR that uses only two cameras and a certain amount of math to do its thing. He knew he could do theoretically, and wouldn’t cost a lot of money, but still required a lot of work and slightly absurd amount of math.
While playing around with a webcam that he’d set up to run an object-tracking Python script and discovered that his setup tended to display a translucent object with a LED inside of it as pure, washed-out white. This gave [Koppany] the idea that he could use such a light as part of his object tracking project. He 3D-printed 50mm hollow spheres out of transparent PLA, illuminated via a LED and powered by a 5V power supply hacked from an old USB cable. After dealing with some lens flares, he sanded down the PLA a little to diffuse the light and it worked like a charm.
To learn more check out his GitHub code repository. You can also take inspiration in some of the other motion tracking posts we’ve published in the past, like motion tracking on the cheap with a PIC and this OpenCV Airsoft turret.
[Matteo] has just released a new installment of his Google Daydream VR controller hack, which we first covered last year (when he got it working with iOS). This time around he’s managed to forge a half Daydream, half PlayStation Move controller hybrid.
The original controller only managed a mere 3 DOF (Degrees of Freedom) using the internal accelerometer; although this conveyed rotational motion around the 3 axis, transitional information was completely lacking. [Matteo] resolves this by forming a simple positional marker out of a white LED enclosed in a standard ping pong ball; He tracks this setup using an iSight camera.
To gel everything together, he adds motion tracking to his already extensively developed software stack, which enables him to unshackle the Daydream controller from Android. He deciphers the Bluetooth packets and streams the sensory information straight to a web browser over a webSocket connection.
The results are quite impressive and the tracking is smooth. Not only does this add to the final goal of hacking his way towards a platform independent VR motion controller, he aptly gets some inspiration from Sony, extends Google’s hardware and even manages to use Apple’s webcam along the way. How’s that for carving passages between the walled gardens of consumer electronics?
Continue reading “Ping Pong Ball Improves the Google Daydream Controller”
How do you make the most awesome gaming peripheral ever made even more bad? Give it a 21st-century upgrade! [Alessio Cosenza] calls this mod the Power Glove Ultra, and it works exactly as we imagined it should have all those years ago.
The most noticeable change is the 3D-printed attachment that hosts the Bluetooth module, a combination USB charger and voltage booster, and a Metro Mini(ATmega328) board. On top of a 20-hour battery life, a 9-axis accelerometer, gyroscope, and compass gives the Power Glove Ultra full 360-degree motion tracking and upgrades the functionality of the finger sensors with a custom board and five flex sensor strips with 256 possible positions for far more nuanced input. [Cosenza] has deliberately left the boards and wires exposed for that cyberpunk, retro-future look that is so, so bad.
Continue reading “The Power Glove Ultra Is The Power Glove We Finally Deserve”
There is a lot of helpful technology for people with mobility issues. Even something that can help people do something most of us wouldn’t think twice about, like turn on a lamp or control a computer, can make a world of difference to someone who can’t move around as easily. Luckily, [Matt] has been working on using webcams and depth cameras to allow someone to do just that.
[Matt] found that using webcams instead of depth cameras (like the Kinect) tends to be less obtrusive but are limited in their ability to distinguish individual users and, of course, don’t have the same 3D capability. With either technology, though, the software implementation is similar. The camera can detect head motion and control software accordingly by emulating keystrokes. The depth cameras are a little more user-friendly, though, and allow users to move in whichever way feels comfortable for them.
This isn’t the first time something like a Kinect has been used to track motion, but for [Matt] and his work at Beaumont College it has been an important area of ongoing research. It’s especially helpful since the campus has many things on network switches (like lamps) so this software can be used to help people interact much more easily with the physical world. This project could be very useful to anyone curious about tracking motion, even if they’re not using it for mobility reasons. Continue reading “Head Gesture Tracking Helps Limited Mobility Students”
Official NFL footballs are crafted by hand by a company in Chicago called Wilson Sporting Goods. The footballs that are made there typically range from 11 to 11.5 inches in length and weigh anywhere between 14 and 15 ounces on average. Originally, animal bladders lined the outside, occasionally from the inside of a pig, giving the traditional American football the long-standing nickname of a “pigskin.” Now a days, they consist of cowhide leather or vulcanized rubber with laces that are stitched to the top adding mass. This causes the oblong spheres to be naturally lopsided. This is fixed by inserting extra weight to the opposite side of the football balancing it out. Knowing this, a clever hacker will realize that the balancing spot is a perfect place to subtly add a motion tracking transmitter like this one. Doing so makes it possible to the track not only the position of the ball on the field, but its precise location in 3D space!
Since each football is unique, variations between one ball to another exist. This means that embedding a circuit into a football only modifies the equipment slightly, which is a good thing because sports fanatics tend to be very opinionated about whether or not technology should influence the game. So long as the transmitter and loop antenna added to the air bladder doesn’t pass that threshold of about an ounce (or so) difference in weight, then the football itself really isn’t affected much.
Continue reading “Tracking Footballs with Magnetic Fields”
A few folks over at Carnegie Mellon have come up with a very simple way to do high-speed motion tracking (PDF) with little more than a flashlight. It’s called Lumitrack, and while it looks like a Wiimote on the surface, it is in reality much more accurate and precise.
The system works by projecting structured light onto two linear optical sensors. The pattern of the light is an m-sequence – basically a barcode where every subset of the m-sequence is unique. By shining this light onto a linear sensor, Lumitrack can calculate where the light is coming from, and thus the position of whatever is holding the light.
Even though the entire system consists of only an ARM microcontroller (in the form of a Maple Mini board), two linear optical sensors, and a flashlight with an m-sequence gel, it’s very accurate and very, very fast. The team is able to read the position at over 1000 frames/second, nearly the limit of what can be done with the Maple’s serial connection.
Already there are some interesting applications for this system – game controllers, including swords, flight yokes, and toy cars, and also more artistic endeavors such as a virtual can of spray paint. It’s an interesting piece of tech, and with the right parts, something any of us can build at home.
You can see the Lumitrack demo video below.
Continue reading “Extremely Precise Positional Tracking”