At long last I had the opportunity to try out the CastAR, a glasses-based Augmented Reality system developed by Technical Illusions. The hardware has been in the works now for a couple of years, but every time we have come across a demo we were thwarted by the long lines that accompany them. This time I was really lucky. [Jeri] gave us a private demo in a suite at the Palazzo during CES 2015. Reflecting on the experience, CastAR is exactly the type of Virtual Reality hardware I’ve been longing for.
[Jeri, Rick and the Technical Illusions crew] have taken the castAR to Kickstarter. We’ve covered castAR a couple of times in the past, but the Kickstarter includes a few new features just ripe for the hacking. First, castAR is no longer confined to a retro-reflective surface. In fact, it’s no longer confined to augmented reality. An optional clip on adapter converts castAR into a “free” augmented reality or a full virtual reality system.
[Jeri] has also posted a video on her YouTube channel detailing the entire saga of castAR’s development (embedded after the jump). The video has a real “heart to heart” feel to it, and is definitely worth watching. The story starts with the early days (and late nights) [Rick] and [Jeri] spent at Valve. She goes through the split with Valve and how the two set up a lab in [Rick’s] living room. [Jeri] also outlines some of the technical aspects of the system. She explains how the optics have been reduced from several pounds of projectors to the mere ounces we see today.
Another surprise addition is the lower level tier rewards of the campaign. The castAR tracking system is offered. The campaign page says the tracking system can be mounted to anything from robots to other VR headsets. The possibilities for hacking are almost endless. We’re curious about setting up our own swarm of quadcopters similar to the UPENN Grasp Lab. The RFID tracking grid is also offered as a separate option. In the gaming system this will be used for tracking tabletop game pieces. Based upon the Kickstarter page, it sounds as if the grid will not only use RFID, but a camera based tracking system. We’re definitely curious what possibilities this will hold.
As of this writing, the castAR Kickstarter campaign is already well past the halfway mark on its way to a $400,000 USD goal.
If there was one sentence heard over and over at Maker Faire NY, it was “Did you see castAR yet?” The Technical Illusions team was at Maker Faire in full force. [Jeri Ellsworth], [Rick Johnson,] and team brought two demos: the tried and true Jenga simulator, and a newer overhead shooter based on the Unity 3D engine. We didn’t see any earth shattering changes from the previous demos of castAR, as [Jeri] has moved into optimization of the Hardware, and [Rick] toward even more immersive demos of the software. Optimization and preparing for market are considered the “hard yards” of any product design. This is the place where a huge amount of work goes in, but the changes are subtle to the layperson.
In addition to her development of castAR’s ASIC, [Jeri] has been hard at work on the optics. The “old” glasses used a solid plastic optical path. The newer glasses use a hollow path for the twin 720p projectors. This makes them even lighter than the previous generation. Weight on the castAR glasses can’t be overstated. They feel incredibly light. There was no perceptible pressure on the nose or ears when wearing them. Also missing was the motion sickness people often experience with VR. This is because castAR doesn’t replace the user’s vision field, it only augments the vision. Peripheral motion cues are still there, which makes for a much more comfortable experience. Continue reading “CastAR Comes To Maker Faire NY 2013”
In the last year, [Jeri Ellsworth] has been very busy. She was hired by Valve, started development of an augmented reality system, fired by Valve, and started a new company with [Rick Johnson] to bring her augmented reality glasses to the market. On the last Amp Hour podcast she spilled the beans on what went down at Valve, how her glasses work, and what her plans for the future are.
[Jeri] and [Rick]’s castAR glasses aren’t virtual reality glasses like the Oculus Rift or other virtual reality glasses that cut you off from the real world. The castAR glasses preserve your peripheral vision by projecting images and objects onto a gray retro-reflective mat and allows you to interact with a virtual environment with an electronic wand. So far, there are a few demos for the castAR system; a Jenga clone, and a game of battle chess called Team For Chess, a wonderful reference to Valve’s hat simulator.
The electronics inside the castAR glasses are fairly impressive; new frames are drawn on the retro-reflective surface at 100 Hz, positioning accuracy is in the sub-millimeter range, and thanks to [Jeri]’s clever engineering the entire system should be priced at about $200. Not too bad for an awesome device that can be used not only for D&D and Warhammer, but also for some very cool practical applications like visualizing engineering models of 3D prints before they’re printed.
Way back when [Ms Ellsworth] was a kid, she kept seeing the same circuit over and over again in her various op-amp books. It was a Wien bridge oscillator, a small circuit that outputs a sine wave with the help of a light bulb. Now that [Jeri] is much wiser, she decided to play around with this strange oscillator and found it’s actually pretty impressive for, you know, a light bulb.
The interesting portion of the Wien bridge is the gain portion of the circuit. It’s just a simple resistor divider, with a light bulb thrown in on one of its legs. When the current increases, this causes the light bulb to warm up (not enough to glow, though). When the temperature increases, the resistance in the light bulb increases, making the oscillator reach an equilibrium.
It’s a clever setup, but what about swapping out a resistor in place of the light bulb? In the video, [Jeri] tries just that, and it’s a mess. Where the light bulb circuit is amazingly stable with very, very low distortion, the resistor circuit looks like a disaster on the scope with harmonics everywhere.
A very cool build that would be perfect for an audio synth, but as [Jeri] says in her YouTube comments, “This doesn’t have enough distortion for indie bands.”
[Jeri] has had a bear of a time moving up to Valve Software, but electron microscope is safely in her garage (!) and her electronics lab is slowly taking shape. Since she can’t bring out the real-life gravity gun she’s working on, she decided to show off a one-bit ADC that uses just a flip-flop to sample an analog waveform into digital data.
By toggling the clock input of a 74xx74 (or any flip-flop, really) and feeding the complimentary output to back into the data input, [Jeri] can get an output that is a 50% duty cycle feeding into the input of the chip. Adding an audio input to this data input with 10k pot to this feedback loop will cause the duty cycle to change in relation to the analog input, making a one-bit ADC.
As with any electronic shortcut, there are a few drawbacks: the clock cycle feeding into the flip-flop has to be pretty fast; at least a few dozen kilohertz if you’re sampling audio. Still, if you don’t have a free ADC pin, or you’d just like to build a bitcrushing guitar pedal, it’s a very simple (and cheap) way to get analog into a digital micro.
Here’s an interesting interview with [Jeri Ellsworth] over at the Jenessee Network. Usually the interviews I see popup with people are fairly short and sweet but this one really delves into many subjects and takes its time to explore. They start off talking about how [Jeri] began with hacking, which was literally smashing toys “with rocks” to see what was inside. They move on to discuss her adventures in building a race car, and then racing it as a teen… as an act of defiance.
In case you didn’t know, [Jeri] has been full time at Valve for about a year. Much of the discussion focuses on this from about 20 minutes in. She doesn’t hold back on information about what her daily life is like at valve as well as her experience during the hiring process. An interesting fact is that she didn’t initially recognize the name “Valve” and ignored them for a while. She does admit that if they had mentioned portal she would have paid a little more attention.
I was unaware that she had a side job putting the overflow of pinball machines she aquires into bars. When she moved to valve, she shut down that business, but she’s been flooding the halls with pinball machines, much to the enjoyment of the older folks.