EMG Controlled Prosthesis

May 4, 2010 by Mike Szczys 7 Comments

This prosthetic arm is the result of a student project. [Amnon Demri] and his classmates built it with below-the-elbow amputees in mind. It uses electromyography to actuate the fingers and wrist. Four stick-on sensors are placed around the elbow to sense electrical activity there. These signals are interpreted by a PIC 16f877a microcontroller which then controls the servo motors to operate the prosthetic limb. This sounds like a very economical solution and as you can see in the videos after the break, it works fairly well.

Continue reading “EMG Controlled Prosthesis” →

DIY Pulse Oximeter

May 2, 2010 by Mike Szczys 28 Comments

This pulse oximeter turned out very nicely. It is based around a Freescale microcontroller and detects pulse as well as oxygen saturation in your blood. The sensor is made of two wood pieces and allows two wavelengths of light to be shined through your finger. A sensor picks up the light on the other side of your stubby digit and the readings are compared to calculate saturation. Check out the finished project after the break.

We saw an Arduino-based oximeter a few months ago. These kind biometric hacks are rare around here. If you’ve got a well documented project don’t forget to tell us about it.

Continue reading “DIY Pulse Oximeter” →

Pulse Oximeter

January 6, 2010 by Mike Szczys 15 Comments

[youtube=http://www.youtube.com/watch?v=GdN5IRVJOXI]

[Mike] is building his own Pulse Oximeter which uses light to measure the oxygen saturation in blood. One collateral benefit of this measurement is that pulse rate can be calculated from the same data. The parts used for the detector include a red LED, infrared LED, and a TSL230R light intensity measuring chip. As explained in the video above, each LED is shined through the tip of your finger and onto the light sensor. The IR LED is used as a baseline and compared to the red LED, which has some of its intensity absorbed by the red blood in your finger. This is a pretty approachable biometric concept so you may want to start here before moving on to more involved biometric interfaces.

[Thanks Russ]

Door Opening Help

November 27, 2009 by Caleb Kraft 21 Comments

For those who are seeking prosthetic limbs, or just require a little bit of robotic gripper help, the choices are very few and very costly. A newcomer to the area is hoping to change the costly part with their door opening arm. Costing only $2,000 to build, it is quite cheap compared to the other offerings. This arm can grip, twist, and swing its arm at the same time using a single motor thanks to a slip clutch.

[via Popular Science]

25 Scariest Experiments

November 4, 2009 by Caleb Kraft 113 Comments

[youtube=http://www.youtube.com/watch?v=Jq06D0xRWmc]

Warning: This video contains actual footage of a severed dog head, kept alive. Watch at your own peril.

[Annalee] over at io9.com has gathered together the 25 scariest science experiments. There are some truly frightening pieces, like the cyborg beetles which we’ve seen before, all the way to silly stuff like the guy who re grew his thumb using pig powder. Next time you’re thinking of admonishing someone for creating a flamethrower, or a super fast scooter, consider for a moment that they’re not burning peoples nasal passages to stop masturbation or creating zombie severed dog heads like the one in the video above.

Dean Kamen’s Prosthetic Arm

September 30, 2009 by Caleb Kraft 26 Comments

luke

60 minutes has covered [Dean Kamen]’s modular robotic arm. This thing is light weight, adjustable for different body frame sizes, modular, and eventually thought controlled. The system is currently functioning quite well, as you can see in the video. Current testers are controlling it with buttons under their toes, but the thought control is in the later stages of development. Sounds like science fiction right? You can see a monkey using a thought controlled arm to feed itself grapes, though we don’t think it is [Dean]’s arm.

Another cool feature of this arm is the fact that it changes its grip on your body depending on how much weight you are lifting. Lift something heavy and it grips harder. Though it has a lot of the same information, there is a little bit of different footage in [Dean]’s TED talk about the arm.

It seems to us, with microcontrollers becoming so cheap and accessible that we should be seeing more home made contraptions in this area. Are any of you working with prosthetics?

Collect And Analyze ECG Data

August 22, 2009 by Zach Banks 14 Comments

ecg

Although we’ve covered DIY ECGs before, [Scott Harden] sent in his version that gives an in-depth explanation of what to do with the collected data. He built a basic battery-powered op-amp-based ECG for under $1. The circuit just amplifies the signal from the chest leads and feeds it into a computer via the microphone port. He then used GoldWave to record, filter, and save the signal. From there, he used python to analyze the heartbeat and calculate his heart rate and further manipulate the data. His previous blog posts go into more detail on how the python code works and why he chose software over hardware filters.