Eye-Controlled Wheelchair Advances From Talented Teenage Hackers

May 28, 2015 by Anool Mahidharia 19 Comments

[Myrijam Stoetzer] and her friend [Paul Foltin], 14 and 15 years old kids from Duisburg, Germany are working on a eye movement controller wheel chair. They were inspired by the Eyewriter Project which we’ve been following for a long time. Eyewriter was built for Tony Quan a.k.a Tempt1 by his friends. In 2003, Tempt1 was diagnosed with the degenerative nerve disorder ALS and is now fully paralyzed except for his eyes, but has been able to use the EyeWriter to continue his art.

This is their first big leap moving up from Lego Mindstorms. The eye tracker part consists of a safety glass frame, a regular webcam, and IR SMD LEDs. They removed the IR blocking filter from the webcam to make it work in all lighting conditions. The image processing is handled by an Odroid U3 – a compact, low cost ARM Quad Core SBC capable of running Ubuntu, Android, and other Linux OS systems. They initially tried the Raspberry Pi which managed to do just about 3fps, compared to 13~15fps from the Odroid. The code is written in Python and uses OpenCV libraries. They are learning Python on the go. An Arduino is used to control the motor via an H-bridge controller, and also to calibrate the eye tracker. Potentiometers connected to the Arduino’s analog ports allow adjusting the tracker to individual requirements.

The web cam video stream is filtered to obtain the pupil position, and this is compared to four presets for forward, reverse, left and right. The presets can be adjusted using the potentiometers. An enable switch, manually activated at present is used to ensure the wheel chair moves only when commanded. Their plan is to later replace this switch with tongue activation or maybe cheek muscle twitch detection.

First tests were on a small mockup robotic platform. After winning a local competition, they bought a second-hand wheel chair and started all over again. This time, they tried the Raspberry Pi 2 model B, and it was able to work at about 8~9fps. Not as well as the Odroid, but at half the cost, it seemed like a workable solution since their aim is to make it as cheap as possible. They would appreciate receiving any help to improve the performance – maybe improving their code or utilising all the four cores more efficiently. For the bigger wheelchair, they used recycled car windshield wiper motors and some relays to switch them. They also used a 3D printer to print an enclosure for the camera and wheels to help turn the wheelchair. Further details are also available on [Myrijam]’s blog. They documented their build (German, pdf) and have their sights set on the German National Science Fair. The team is working on English translation of the documentation and will release all design files and source code under a CC by NC license soon.

Hackaday Prize Entry: Biopotential Signal Library

May 22, 2015 by Brian Benchoff 11 Comments

With prosthetics, EEG, and all the other builds focused on the body and medicine for this year’s Hackaday Prize, it might be a good idea to take a look at what it takes to measure the tiny electrical signals that come from the human body. Measuring brain waves or heartbeats indoors is hard; AC power frequencies easily couple to the high impedance inputs for these measurements, and the signals themselves are very, very weak. For his entry to The Hackaday Prize, [Paul Stoffregen] is building the tools to make EEG, ECG, and EMG measurements easy with cheap tools.

If the name [Stoffregen] sounds familiar, it’s because he’s the guy behind the Teensy family of microcontroller boards and several dozen extremely popular libraries for everything from displays to real time clocks. The biopotential signal library continues in [Paul]’s tradition of building very cool stuff with just code.

The hardware used in this project is TI’s ADS1294, a 24-bit ADC with either 4 or 8 channels. This chip is marketed as a medical analog front end with a little bit of ECG thrown in for good measure. [Paul] is only using the ADS1294 initially; more analog chips can be added later. It’s a great project in its own right, and when you include the potential applications of this library – everything from prosthetics to body sensors – it makes for an awesome Hackaday Prize entry.

The 2015 Hackaday Prize is sponsored by:

Hackaday Prize Entry: Aspirin For Everyone

May 6, 2015 by Brian Benchoff 62 Comments

When it comes to the history of medicine and drugs, Aspirin, or more properly acetyl-salicylic acid, is one of the more interesting stories. Plants rich in salicalates were used as medicines more than four thousand years ago, and in the fourth century BC, [Hippocrates] noted a powder made from willow bark was an excellent analgesic. It was only in the 1800s that acetylated salicylic acid was first synthesized. In 1897, chemists at Bayer gave this ancient remedy a new name: Aspirin. It’s on the WHO List of Essential Medicines, but somehow millions of people don’t have access to this pill found in every pharmacy.

[M. Bindhammer] is working to make Aspirin for Everyone for his entry to the Hackaday Prize, using a small portable lab designed around chemicals that can be easily obtained.

The most common synthesis of Aspirin is salicylic acid treated with acetic anhydrate. Acetic anhydrate is used for the synthesis of heroin, and of course the availability of this heavily restricted by the DEA. Instead, [M. Bindhammer] will use a different method using salicylic acid and acetic acid. If you’re keeping track, that’s replacing a chemical on a DEA list of precursors with very strong vinegar.

[M. Bindhammer] even has a design for the lab that will produce the Aspirin, and it’s small enough to fit in a very large pocket. Everything that is needed for the production of acetyl-salicylic acid is there, including a reaction vessel with a heating element, a water/oil bath, flask, an Allihn condenser, and a vacuum filtering flask. Even if shipping millions of pills to far-flung reaches of the planet were easy, it’s still an exceptional Hackaday Prize entry.

The 2015 Hackaday Prize is sponsored by:

We Have A Problem: Health Care Where There Are No Health Care Workers

April 16, 2015 by Mike Szczys 46 Comments

Hackaday, we have a problem. There are a lot of people on this earth and not a lot of health care workers. Let’s use our skills to help alleviate this problem. What can we do to give medical professionals a wider reach, to bridge the distances between hospital and patient, and make it easier for bystanders to administer lifesaving care.

Scope of the Problem

We’d wager that your most recent and vivid remembrance of a health care worker shortage is the Ebola outbreak in West Africa. The shortage of trained professionals and supplies certainly compounded the situation in the countries worst hit. But it didn’t create the problem. Check out this list of doctors per 1,000 people (sorted lowest-to-highest with 2010 numbers). The three countries hit hardest by the outbreak — Guinea, Liberia, and Sierra Leone — register a whopping 0.0 doctors for every 1000 people. Yeah, that’s years before the outbreak.

Keep scrolling down and you’ll see that this isn’t limited to one geographic location. All over the world there are low numbers, with India and Iraq both at 0.6, and interestingly Cuba and Qatar topping the list at 6.7 and 7.7 respectively.

This isn’t a statistics post so let’s pivot. The point is made that we’re a large world population. What kind of engineering solutions can we wield to help provide everyone with the care they need? Leave your comments below but also considered entering the Hackaday Prize with them. Write down your idea as a Hackaday.io project and tag it 2015 Hackaday Prize.

Proof That We Can Do This

It’s safe to say we’ve all seen engineering solve part of this problem already. Over the last decade, Automatic External Defibrillators have become ubiquitous. The life-saving hardware is designed to be used by non-doctors to save someone whose heart rhythms have become irregular. [Chris Nefcy] helped develop AEDs and one ended up saving his life. If that’s not proof that we can change the world with our builds we don’t know what is.

Pull on that thinking cap and jump into this conversation. What can we build? What problems need to be solved right now? Where should each of us be looking to make a difference in the availability of health care in the absence of the trained professionals?

The 2015 Hackaday Prize is sponsored by:

Wounded Soldier Gets Robotic Hand Replacement

April 12, 2015 by James Hobson 47 Comments

[Neal Muzzy], a local member of the Cedar Valley Makers makerspace, just made news on Open Bionics for his robotic prosthetic hand called Dextrus v1.2 which he made for his friend, and wounded war veteran, [Taylor].

In just two months, [Neal] worked with his friend to make this robotic prosthetic with the goal of having it more functional and easier to use than [Taylor]’s current prosthetic. The very first prototype was made by using the open-source Dextrus design, to test fit, and control using EMG sensors. Once they determined it would work — onto customizing!

They call it Dextrus V1.2, and it works better for [Taylor] than the original — but that’s the whole point of the Open Hand project — starting with a base design, and making it better. If you’re not familiar with the Open Hand Project, it was originally crowd-funded on Indiegogo, and is now an organization to make robotic prosthetic hands more accessible to amputees. We wrote about it in Hacklet 41 – Prosthetic Projects.

Continue reading “Wounded Soldier Gets Robotic Hand Replacement” →

Measuring Heart Rate With A Piezo

March 19, 2015 by Brian Benchoff 13 Comments

Look around for heart rate sensors that interface easily to microcontrollers, and you’ll come up with a few projects that use LEDs and other microcontrollers to do the dirty work of filtering out pulses in a wash of light.

[Thomas] was working on a project that detects if water is flowing through a pipe with a few piezoelectric sensors. Out of curiosity, he taped the sensor to his finger, and to everyone’s surprise, the values his microcontroller were spitting out were an extremely noise-free version of his heart rate.

The piezo in question is a standard, off the shelf module, and adding this to a microcontroller is as easy as putting the piezo on an analog pin. From there, it’s just averaging measurements and extracting a heartbeat from the data.

It’s a much simpler solution to measuring a heart rate, and since two people haven’t heard of this technique, it’s likely a lot more people haven’t heard of this technique either. If you’re looking for an entry to The Hackaday Prize, this would be a great jumping off point for anything in either the fitness or medical domains.

Brains Controlling Labyrinths Without Hands

March 17, 2015 by Brian Benchoff 10 Comments

[Daniel], [Gal] and [Maxim] attended a hackathon last weekend – Brainihack 2015 – that focused on neuroscience-themed builds in a day and a half long build off. The trio are communications systems engineering and computer science students with no background in neuroscience whatsoever. You can’t build an FMRI in a day and a half, so they ended up winning the best project in the open source category with a brain-controlled labyrinth game.

The labyrinth itself is entirely 3D printed and much, much simpler than the usual, ‘wooden maze with holes’ that’s generally associated with labyrinth puzzles. It’s really just a plastic spiral for a ball to follow. There’s a reason for this simplicity. The team is using EEG to detect brain waves and move the labyrinth on the X and Y axes.

The team is using OpenBCI for the interface between their brains and a pair of servos. This is actually an interesting piece of tech; unlike a few toys like the NeuroSky MindWave and the Star Wars Force Trainer, the OpenBCI gives you eight input channels that attach to anywhere on the scalp. The team used these inputs to measure Alpha waves and Steady State Visually Evoked Potential to control the pair of servos on the labyrinth frame.

It’s a great build, a wonderful demonstration of a device that outputs real EEG signals, and the team on a prize. What’s not to like?