Medical Hacks

685 Articles

Measuring Ketosis With An Arduino

June 27, 2013 by 19 Comments

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A bit of biology and nutrition before we roll into this: Ketosis is when your body runs on fat reserves instead of carbohydrates. This is the basis of diets such as Atkins, and despite the connotations of eating hamburger patties and butter, you can actually lose weight on these diets. One problem with a keto diet is the difficulty of measure how many ketones your liver is processing; this can be done with a urine sample, but being able to measure small amounts of acetone in your breath would be the ideal way to measure ketosis. [Jens] came up with a device that does just that. It’s called Ketosense, and it will tell you how well your keto diet is doing by just having you blow into a sensor.

[Jens]’ device consists of an Arduino, LCD display, and two sensors – one for acetone, and another for temperature and humidity. By carefully calibrating a TGS822 sensor, [Jens] was able to measure the acetone content of an exhaled breath along with temperature and pressure. This gave him a reading in parts per million, and with a short bit of math was able to convert that into something that made sense when talking about ketosis, mmol/l.

Without access to a lab that can measure blood ketone levels, it’s difficult to say if [Jens] device really works as intended. If he were to find his way into a lab, though, it would be possible to correlate his sensor’s values with blood ketone results and improve the accuracy of his sensor.

Building An IR Mouse Interface For The Disabled

June 26, 2013 by 9 Comments

[Chris Young] has a physical disability that means he can’t use a mouse very well. He typically uses Dragon Naturally Speaking for moving his mouse using voice commands but has found that it lacks some features he needs and can crash at times.

His solution to this problem was to create a device that will translate IR signals from a simple remote into mouse actions and movements. He is using an Arduino micro for this task, and as you can see in the video it seems to have worked out well for him. He has code and schematics available on his site if you would like to recreate this yourself.

[Chris] has actually built several accessibility devices for himself and others. You should check out his blog for more, including his thoughts on the cost of commercial accessibility equipment vs DIY. If you think you would like to try making a device to help someone with a physical disability access a computer, hop on over to thecontrollerproject.com and join up on the forums.

 

via thecontrollerproject.com

[Ricky’s] Rugged DVD Player

June 22, 2013 by 25 Comments

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[Ricky] absolutely loves watching DVDs. He is epileptic and is cognitively functioning at a level roughly that of a 6 year old.  His younger brother [Ronnie] noticed that [Ricky’s] DVDs as well as his DVD player never lasted very long due to some rough handling. [Ronnie] stepped up to make [Ricky’s] life just a little bit easier by building this super rugged DVD watching station.

He started by ripping out the front pcb of the DVD player that has all the buttons. [Ricky] can wear through a set of standard buttons in no time, so [Ronnie] extended these to arcade buttons. Then he mounted everything into a custom cabinet that can withstand a considerable amount of abuse.

Now they can load 5 disks in and [Ricky] can watch what he pleases without worry of destroying the player.

[Ronnie] mentioned that he’d like to make a more complex control system using some kind of microcontroller, but frankly I find the simplicity of this to be perfect. Maybe a media pc loaded with movies might be a decent next step. You can see [Ronnie’s] build log here.

If you’ve ever considered making something like this to improve someone’s life, you should check out thecontrollerproject.com where people with special needs can connect with people who can build interfaces.

Building Custom Game Controllers For People With Physical Disabilities

June 20, 2013 by 81 Comments

 

Hold on tight. This is going to be a long post. I kept my temper in the video, but here I can just come out and let you know that I’m livid. Every time I start thinking about this, I feel so angry and helpless that my face gets hot and my hands get shaky.  I’m getting ahead of myself though, so lets just back up a little bit and talk about a pretty cool kid named [Thomas].

[Thomas] has muscular dystrophy. This means he’s going to gradually lose strength and control in his muscles over time. He has already lost his ability to stand, and even holding buttons on a game-pad for extended times can be difficult. Gaming, as you can imagine, is very important to [Thomas] and people like him. It offers a release of frustration, like it does for all of us, but also a level playing ground. When he’s in the game, he’s like everyone else.

Continue reading “Building Custom Game Controllers For People With Physical Disabilities” →

Modeling Squid Cells In Code Foregoes Connecting Voltage To Animals

June 20, 2013 by 4 Comments

[Kemper Smith] built a little piece of nature in Processing. He was inspired by a biology experiment that excited squid cells using electricity. The result is an interactive display that mimics that biology.

Last August we saw a peculiar experiment that forced Cyprus Hill music on the color changing cells of a squid. The cells make colors by stretching sacs of pigment; the larger they get the more of that color is shown. Normally this is used for camouflage. The image on the left is the reaction from connecting headphone wires while music is being played.

But we can’t all get our hands on this type of wet-ware — especially if life far inland. So [Kemper] got to work writing some Processing code. The result is seen on the right. It does a good job of replicating the motion and color palette of the original. He’s put together a web-based demonstration which you can interact with using your mouse cursor. But we also saw him demonstrate a Kinect based version at our local hackerspace.

Continue reading “Modeling Squid Cells In Code Foregoes Connecting Voltage To Animals” →

Shocking Your Brain And Making Yourself Smarter

May 28, 2013 by 52 Comments

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Transcranial Direct Current Stimulation – or tDCS – is the technique of applying electrodes to the skull and running a small but perceptible current through them. It’s not much current – usually on the order of 1 or 2 mA, but the effect of either increasing or decreasing neural activity has led to some interesting studies. [Theo] over on Instructables wrote a tutorial for making his own tDCS suppy that will supply 2 mA to electrodes placed on the skull for everyone to experiment with.

The basic idea behind tDCS is to put the positive electrode over the part of the brain to be excited or the negative electrode over the part of the brain to be inhibited. This is a well-studied technique that can be used to improve mathematical ability. It’s not electroshock therapy (although that is a valid treatment for depression and schizophrenia) in that a seizure is induced; tDCS just applies a small current to specific areas of the brain to excite or inhibit function.

[Theo]’s device is a simple circuit made of a transistor, resistors, and a few diodes to provide about 2 mA to a pair of electrical contacts. With this circuit and a few gel electrode pads for your head, you too can experiment with direct current stimulation of your brain.

Of course we need to warn you about putting electricity into your head. In any event, here’s a quadcopter / stun gun mashup we made. Don’t do that, either. You might get a takedown request.