It’s a parent’s worst nightmare. Doctors tell you that your baby is sick and there’s nothing they can do. Luckily though, a combination of hacks led to a happy ending for [Teegan Lexcen] and her family.
When [Cassidy and Chad Lexcen]’s twin daughters were born in August, smaller twin [Teegan] was clearly in trouble. Diagnostics at the Minnesota hospital confirmed that she had been born with only one lung and half a heart. [Teegan]’s parents went home and prepared for the inevitable, but after two months, she was still alive. [Cassidy and Chad] started looking for second opinions, and after a few false starts, [Teegan]’s scans ended up at Miami’s Nicklaus Children’s Hospital, where the cardiac team looked them over. They ordered a 3D print of the scans to help visualize possible surgical fixes, but the 3D printer broke.
Not giving up, they threw [Teegan]’s scans into Sketchfab, slapped an iPhone into a Google Cardboard that one of the docs had been playing with in his office, and were able to see a surgical solution to [Teegan]’s problem. Not only was Cardboard able to make up for the wonky 3D printer, it was able to surpass it – the 3D print would only have been the of the heart, while the VR images showed the heart in the context of the rest of the thoracic cavity.[Dr. Redmond Burke] and his team were able to fix [Teegan]’s heart in early December, and she should be able to go home in a few weeks to join her sister [Riley] and make a complete recovery.
We love the effect that creative use of technology can have on our lives. We’ve already seen a husband using the same Sketchfab tool to find a neurologist that remove his wife’s brain tumor. Now this is a great example of doctors doing what it takes to better leverage the data at their disposal to make important decisions.
Modern DSLR cameras are amazing devices. Mechanics, electronics, and optics, all rolled up in a single package. All that technology is great, but it can make for a frustrating experience when attempting any sort of repair. Lenses can be especially difficult to work on. One misalignment of a lens group or element can lead to a fuzzy image.
[Kratz] knew all this, but it didn’t stop him from looking for a cheap lens deal over on eBay. He found a broken Nikon DSLR 55-200mm 1:4-5.6 AF-S VR camera lens for $30. This particular lens is relatively cheap – you can pick up a new one for around $150 online. Spending $30 to save $120 is a bit of a gamble, but [Kratz] went for it.
The lens he bought mostly worked – the auto-focus and vibration reduction system seemed to be fine. The aperture blades however, were stuck closed. Aperture blades form the iris of a lens. With the blades closed down, the lens was severely limited to brightly lit situations. All was not lost though, as the aperture is a relatively simple mechanical system, which hopefully would be easy to repair.
Keeping screws and various parts in order is key when taking apart a lens. [Kratz] used a tip he learned right here on Hackaday: He drew a diagram of the screw positions on a thick piece of paper. He then stuck each screw right into the paper in its proper position.
Carefully removing each part, [Kratz] found a pin had slipped out of the rod that connects the lens’ internal parts with the external aperture control arm. Fixing the pin was simple. Getting the lens back together was quite a bit harder. Several parts have to be aligned blindly. [Kratz] persevered and eventually everything slipped into alignment. The finished lens works fine, albeit for a slightly noisy auto-focus.
It’s worth noting that there are service and repair manuals for many cameras and lenses out there in the dark corners of the internet, including [Kratz]’s 55-200 lens. Reading the repair procedures Nikon techs use shows just how many tools, fixtures, and custom bits of software go into making one of these lenses work.
In the next few years, VR headsets will be everywhere, and everyone will slowly recede into their own little reality that is presented on high-resolution displays right in front of their eyes. One specific group will be left out: eyeglass wearers. VR just doesn’t work with eyeglasses, and a few people in Germany are fixing this problem. They’re creating custom prescription lenses for Google Cardboard, giving anyone with glasses the opportunity to look just a little more hipster.
The folks behind this Indiegogo already run a specialty optics shop in Germany. They have the tools to make custom lenses for spectacles, and they’re the first company so far that has identified a problem with the current crop of VR headsets and has created a solution. The campaign is for a set of lenses that can be attached to Google Cardboard with double stick tape. There are limitations on how strong of a prescription they can make, but it should work for most four eyes.
It should be noted this Indiegogo isn’t the only way to get custom lenses for a VR headset. If you have your prescription, there are a few places to buy glasses online for $30 or so. Do that, remove the lenses from the frame, and affix them to Cardboard.
[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!
What would happen if Oculus-quality virtual reality was created in the 80s on the Commodore PET? [Michael Hill] knows, because he created a stereoscopic video headset using a PET.
This build is an extension of [Michael]’s exhibit last year at VCF East where he displayed a video feed with PETSCII. Yes, that means displaying video with characters, not pixels.
This year, he’s doubling the number of screens, and sending everything to two iPhones in a Google Cardboard-like VR headset. Apart from the optics, the setup is pretty simple: cameras get image data, it’s sent over to a PET, and a stream of characters are sent back.
It’s impossible to film, and using it is interesting, to say the least. Video below.
Continue reading “VCF East X: Virtual Reality With PETSCII”
Virtual reality has come a long way but some senses are still neglected. Until Smell-O-Vision happens, the next step might be feeling the wind in your hair. Perhaps dad racing a sportbike or kids giggling on a rollercoaster. Not as hard to build as you might think, you probably have the parts already.
Off-the-shelf devices serve up the seeing and hearing part of your imaginary environment, but they stop there. [Jared] wanted to take the immersion farther by being able to feel the speed, which meant building his own high power wind generator and tying it into the VR system. The failed crowdfunding effort of the “Petal” meant that something new would have to be constructed. Obviously, to move air without actually going on a rollercoaster requires a motor controller and some fans. Powerful fans.
A proponent of going big or going home, [Jared] picked up a pair of fans and modified them so heavily that they will launch themselves off of the table if not anchored down. Who overdrives fans so hard they need custom heatsinks for the motors? He does. He admits he went overboard and sensibly way overbudget for most people but he built it for himself and does not care.
Continue reading ““Superfan” Gaming Peripheral Lets You Feel Your Speed”
Many of us have gone on a stationary romp through some virtual or augmented scape with one of the few headsets out in the wild today. While the experience of viewing a convincing figment of reality is an exciting sensation in itself, [Mark Lee] and [Kevin Wang] are figuring out how to tie other senses into the mix.
The duo from Cornell University have built a mechanical exoskeleton that responds to light with haptic feedback. This means the wearer can touch the sphere of light around a source as if it were a solid object. Photo resistors are mounted like antenna to the tip of each finger, which they filed down around the edges to receive a more diffused amount of light. When the wearer of the apparatus moves their hand towards a light source, the sensors trigger servo motors mounted on the back of the hand to actuate and retract a series of 3D printed tendons which arch upward and connect to the individual fingers of the wearer. This way as the resistors receive varying amounts of light, they can react independently to simulate physical contours.
One of the goals of the project was to produce a working proof of concept with no more than 100 dollars worth of materials, which [Mark] and [Kevin] achieve with some cash to spare. Their list of parts can be found on their blog along with some more details on the project.
Continue reading “Touching Light with Haptic Feedback”