[Alan Yates] brought a demo of Valve’s new VR tech that’s the basis of the HTC Vive system to Maker Faire this year. It’s exceptionally clever, and compared to existing VR headsets it’s probably one of the best headtracking solutions out there.
With VR headsets, the problem isn’t putting two displays in front of the user’s eyes. The problem is determining where the user is looking quickly and accurately. IMUs and image processing techniques can be used with varying degrees of success, but to do it right, it needs to be really fast and really cheap.
[Alan] and [Valve]’s ‘Lighthouse’ tracking unit does this by placing a dozen or so IR photodiodes on the headset itself. On the tracking base station, IR lasers scan in the X and Y axes. By scanning these IR lasers across the VR headset, the angle of the headset to the base station can be computed in just a few cycles of a microcontroller. For a bunch of one cent photodiodes, absolute angles and the orientation to a base station can be determined very easily, something that has some pretty incredible applications for everything from VR to robotics.
Remember all of the position tracking hacks that came out as a result of the Nintendo Wii using IR beacons and a tracking camera? This seems like an evolutionary leap forward but in the same realm and can’t wait to see people hacking on this tech!
Disappointed in the lack of proper VR games and the current technology, [Jonas Hjohlman] and some friends set out to make their own. They decided to go big or go home — and built a device to let them ski in the third person.
We’ve seen this done as a proof of concept for walking around (and getting dizzy!) and even an attempt at third person driving which didn’t end well… We have to say, we’re pretty impressed at the Devil-may-care approach they take when trying to ski of all things — in the third person.
There’s not too much detail about the setup, but it looks like a standard pair of FPV goggles hooked up to their own wireless camera. A cameraman skier follows the player down the hill, and all the player sees is from behind.
Surprisingly, it goes a lot better than you think it would.
Continue reading “Real-Virtual 3rd Person Skiing — Your Broken Bones are the Video Game”
Entirely too excited about Microsoft’s Hololens, the DIY community has leaped on the challenge to make some hardware before the real deal comes out. [Sean Hall] has an excellent 3D printed prototype that makes use of the Pepper’s Ghost illusion to create a “hologram” for this pair of unique VR goggles.
Similar to other DIY virtual reality goggles we’ve seen, [Sean] has 3D printed the enclosure — but instead of slapping the smart phone right in front of your eyes, it’s mounted above the goggles, reflecting off of a mirror and then a piece of transparent plexi-glass, which produces a hologram like effect thanks to the concept of Pepper’s Ghost illusion.
The problem with any of these reflection-based-holograms is they aren’t always that easy to see, so [Sean] is planning to try out some 1-way reflective car tint to get a more visible reflection while still being able to see through the image. He also plans to add gaze tracking with some open-source software called Project Haytham. It’s a depth sensor using a Kinect, head tracking using a Playstation Move and maybe even a leap motion controller for virtual object manipulation.
Check out the current state of this hack in the clip after the break.
Continue reading “DIY Hololens Uses Pepper’s Ghost in a Box!”
Many of the early applications for the much anticipated Oculus Rift VR rig have been in gaming. But it’s interesting to see some more useful applications besides gaming, before it’s commercial release sometime this year. [JoLau] at the Institute i4Ds of FHNW School of Engineering wanted to go a step beyond rendering virtual worlds. So he built the Intuitive Rift Explorer a.k.a IRE. The IRE is a moving reality system consisting of a gimbaled stereo-vision camera rig transmitting video to the Rift, and matching head movements received from the Oculus Rift. The vision platform is mounted on a Remote-controlled robot which is completely wireless.
One of the big challenges with using VR headsets is lag, causing motion sickness in some cases. He had to tackle the problem of latency – reducing the time from moving the head to getting a matching image on the headset – Oculus Rift team specified it should be less than 20ms. The other important requirement is a high frame rate, in this case 60 frames per second. [JoLau] succeeded in overcoming most of the problems, although in conclusion he does mention a couple of enhancements that he would like to add, given more time.
[JoLau] provides a detailed description of the various sub-systems that make up IRE – the Stereo camera, audio and video transmission, media processing, servo driven gimbal for the stereo camera, and control system code. [JoLau]’s reasoning on some of the interesting hardware choices for several components used in the project makes for interesting reading. Watch a video of the IRE in action below.
Continue reading “Putting Oculus Rift on a Robot”
With Samsung’s new Gear VR announced, developers and VR enthusiasts are awaiting the release of the smartphone connected VR headset. A few people couldn’t wait to get their hands on the platform, so they created, OpenGear, a Gear VR compatible headset.
The OpenGear starts off with a Samsung Galaxy Note 4, which is the target platform for the Gear VR headset. A cardboard enclosure, similar to the Google Cardboard headset, holds the lenses and straps the phone to your face.
The only missing part is the motion tracking electronics. Fortunately, ST’s STM32F3 Discovery development board has everything needed: a microcontroller with USB device support, a L3GD20 3 axis gyro, and a LSM303DLHC accelerometer/magnetometer. These components together provide a USB inertial measurement unit for tracking your head.
With the Discovery board strapped to the cardboard headset, an open-source firmware is flashed. This emulates the messages sent by a legitimate Oculus Rift motion tracker. The Galaxy Note 4 sees the device as a VR headset, and lets you run VR apps.
If you’re interested, the OpenGear team is offering a development kit. This is a great way for developers to get a head start on their apps before the Gear VR is actually released. The main downside is how you’ll look with this thing affixed to your face. There’s a head-to-head against the real Gear VR after the break.
[via Road To VR]
Continue reading “Build Your Own Gear VR”
If you’ve been keeping your skills fresh with any console video games in the last 15 years (or you’ve acquired a smartphone), you’ll know that “rumble,” or “haptic” feedback plays a key role in augmenting our onscreen (or touch-screen typing) experience. Nevertheless, this sort of rumble feedback is surprisingly boolean, and hasn’t developed into a richer level of precision since it started to be introduced in gaming over 30 years ago. In response, [Martin] and his fellow design teammates at the University of Salzburg, Austria have introduced the TorqueScreen, a mobile haptic attachment that puts a twist on conventional force feedback.
At its core the TorqueScreen is a gyroscope attached to a servo with the respective rotational axes in a perpendicular alignment. When the servo rotates the live gyroscope, the user can sense the tablet’s resistance to rotate about the servos axis.
The team’s conference demonstration model features a brushless motor plucked from an old hard drive controlled by an Arduino and driven manually by a Wii nunchuck. Currently only one rotational axis resists changes in rotation, but a gimbal may be the next step in this project.
We’ve certainly seen budget handheld haptic devices before, but this project allows for an entire spread of responses proportional to the speed at which the gyroscope is rotated about the servo axis.
Unless you’re reading this post on your already-torquescreen-enabled mobile device, it’s a bit difficult to get a feel for what kind of interactions you can produce with this setup. The video (after the break), though, can give you a pretty good idea of what kind of interactivity you’d expect with device clipped onto your tablet.
[via the Tangible, Embedded, and Embodied Interaction Conference]
Continue reading “TorqueScreen: Haptic Feedback On-the-Go”
If you’ve been keeping up with augmented and virtual reality news, you’ll remember that spacial haptic feedback devices aren’t groundbreaking new technology. You’ll also remember, however, that a professional system is notoriously expensive–on the order of several thousand dollars. Grad students [Jonas], [Michael], and [Jordi] and their professor [Eva-Lotta] form the design team aiming to bridge that hefty price gap by providing you with a design that you can build at home.
A quick terminology dive: a spacial haptic device is a physical manipulator that enables exploration of a virtual space through force feedback. A user grips the “manipulandum” (the handle) and moves it within the work area defined by the physical design of the device. Spacial Haptic Devices have been around for years and serve as excellent tools for telling their users (surgeons) what something (tumor) “feels like.”
In our case, this haptic device is a two-link, two-joint system grounded on a base station and providing force feedback with servo motors and tensioned wire ropes. The manipulator itself supports 3-degree-of-freedom movement of the end-effector (translations, but no rotations) which is tracked with encoders placed on all joints. To enable feedback, joints are engaged with cable-drive transmissions.
The design team isn’t new to iterative prototyping. Hailing from CS235, a Stanford course aimed to impart protoyping techniques to otherwise non-tinkerers, the designers have drawn numerous techniques from this course to deliver a fully functional and reproducible setup. In fact, it’s clear that the designers have a strong understanding of their system’s physics, and they capitalize on a few tricks that don’t immediately jump out to us as intuitive. For instance, rather than rigidly fixing their cable to the motor shaft, they simply wrap the cable around the shaft a mere 5 turns such that the force of friction greatly exceeds the threshold amount that would otherwise cause slipping. They also choose plywood–not necessarily because of its price–but more so because of its function as a stiff, layered composite that makes it ideal “lever arm material” for rigidly transferring forces.
For a full breakdown of their design, take a look at their conference paper (PDF) where they evaluate their design techniques and outline the forward kinematics. They’ve also provided a staggeringly comprehensive bill of materials (Google Spreadsheet). Finally, as justifiably open source hardware, they’ve packaged their control software and CAD models into a github repository so that you too can jump into the world of quality force feedback simulation without shelling out the twenty thousand dollars for a professional system.
[via the 2015 Tangible Embedded and Embodied Conference]
Continue reading “Open Source Haptics Kit Aims to Democratize Force Feedback”