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Archive for the ‘Medical hacks’ Category

Students at the University of Illinois at Urbana-Champaign have a brain-computer interface that can measure brainwaves. What did they do with it? They gave it to Alma, a golden labrador, as you can see in the video below. The code and enough info to duplicate the electronics are on GitHub.

Of course, the dog doesn’t directly generate speech. Instead, the circuit watches her brainwaves via an Arduino and feeds the raw data to a Raspberry Pi. A machine learning algorithm determines Alma’s brainwave state and plays prerecorded audio expressing Alma’s thoughts.

Alma’s collar duplicates — to some degree — the fictional collar from the movie Up. Of course, Dug was a bit more loquacious. It isn’t very clear from the video how many states the program classifies. A quick peek at the code reveals five audio clips but only one appears to be wired to the recognizer — the one for a treat. We think it might be a harder problem to figure out when the dog does not want a treat.

The last time we saw a talking dog collar it was phone-controlled. If you really want to probe a brain — canine or human — you could do worse than to check out OpenHardwareExG.

Oh. By the way. Good dog! Very good dog!

Building a real-life version of the Star Trek tricorder has been the goal of engineers and hackers alike since the first time Dr McCoy complained about being asked to work outside of his job description. But while modern technology has delivered gadgets remarkably similar in function, we’ve still got a long way to go before we replicate 24th century Starfleet design aesthetic. Luckily there’s a whole world of dedicated hackers out there who are willing to take on the challenge.

[Taste The Code] is one such hacker. He wanted to build himself a practical gadget that looked like it would be at home on Picard’s Enterprise, so he gathered up the components to build a hand-held heart rate monitor and went in search for a suitable enclosure. The electronics were simple enough to put together thanks to the high availability and modularity we enjoy in a post-Arduino world, but as you might expect it’s somewhat more difficult to put it into a package that looks suitably sci-fi while remaining functional.

Internally his heart rate monitor is using an Arduino Pro Mini, a small OLED screen, and a turn-key pulse sensor which was originally conceived as a Kickstarter in 2011 by “World Famous Electronics”. Wiring is very simple: the display is connected to the Arduino via I2C, and the pulse sensor hooks up to a free analog pin. Everything is powered by 3 AA batteries delivering 4.5 V, so he didn’t even need a voltage regulator or the extra components required for a rechargeable battery pack.

Once everything was confirmed working on a breadboard, [Taste The Code] started the process of converting a handheld gyroscopic toy into the new home of his heart rate monitor. He kept the battery compartment in the bottom, but everything else was stripped out to make room. One hole was made on the pistol grip case so that a finger tip could rest on the pulse sensor, and another made on the side for the OLED screen. This lets the user hold the device in a natural way while getting a reading. He mentions the sensor can be a bid fiddly, but overall it gives accurate enough readings for his purposes.

If you’re more interested in the practical aspects of a real-life Star Trek tricorder we’ve seen several projects along those lines over the years, including a few that were entered into the Hackaday Prize.

Inspired by an old Old Spice commercial, [Juliodb96] decided he too wanted to make music by flexing his muscles. An Arduino and a MyoWare sensor did the trick. However, he also tells you how to make your own sensors, if you are so inclined. You can see the instrument in action in the video below.

If you use the ready-made MyoWare sensors, this is a pretty easy project. You just respond to sensor input by playing some notes. If you decide to roll your own, you’ll have some circuit building ahead of you.

In particular, the signal conditioning for the sensors involves filtering to eliminate signals not in the 20 Hz to 300 Hz passband, several amplifiers, a rectifier, and a clipper. This requires 3 IC packages and a handful of discrete components.

Unlike the original commercial (see the second video, below), there are no moving parts for actuating actual instruments. However, that wouldn’t be hard to add with some servo motors, air pumps, and the like. This may seem frivolous, but we had to wonder if it could be used to allow musical expression for people who could not otherwise play an instrument.

This isn’t the first time we’ve seen the MyoWare in action. We’ve even talked about signal processing that is useful for this kind of application.

CPAP (Continuous Positive Airway Pressure) machines can be life-changing for people with sleep apnea. [Scott Clandinin] benefits from his CPAP machine and devised a way to improve his quality of life even further with a non-destructive modification to monitor his machine’s humidifier.

With a CPAP machine, all air the wearer breathes is air that has gone through the machine. [Scott]’s CPAP machine has a small water reservoir which is heated to humidify the air before it goes to the wearer. However, depending on conditions the water reservoir may run dry during use, leading to the user waking up dried out and uncomfortable.

To solve this in a non-invasive way that required no modifications to the machine itself, [Scott] created a two-part device. The first part is a platform upon which the CPAP machine rests. A load cell interfaced to an HX711 Load Cell Amplifier allows an Arduino Nano to measure the mass of the CPAP machine plus the integrated water reservoir. By taking regular measurements, the Arduino can detect when the reservoir is about to run dry and sound an alarm. Getting one’s sleep interrupted by an alarm isn’t a pleasant way to wake up, but it’s much more pleasant than waking up dried out and uncomfortable from breathing hot, dry air for a while.

The second part of the device is a simple button interfaced to a hanger for the mask itself. While the mask is hung up, the system is idle. When the mask is removed from the hook, the system takes measurements and goes to work. This makes activation hassle-free, not to mention also avoids spurious alarms while the user removes and fills the water reservoir.

Non-invasive modifications to medical or other health-related devices is common, and a perfect example of nondestructive interfacing is the Eyedriveomatic which won the 2015 Hackaday Prize. Also, the HX711 Load Cell Amplifier has an Arduino library that was used in this bathroom scale refurb project.

Filed under: Arduino Hacks, Medical hacks, The Hackaday Prize

These days we are a little spoiled. There are many sensors you can grab, hook up to your favorite microcontroller, load up some simple library code, and you are in business. When [Raivis] got a MAX30100 pulse oximeter breakout board, he thought it would go like that. It didn’t. He found it takes a lot of processing to get useful results out of the device. Lucky for us he wrote it all down with Arduino code to match.

A pulse oximeter measures both your pulse and the oxygen saturation in your blood. You’ve probably had one of these on your finger or earlobe at the doctor’s office or a hospital. Traditionally, they consist of a red LED and an IR LED. A detector measures how much of each light makes it through and the ratio of those two quantities relates to the amount of oxygen in your blood. We can’t imagine how [Karl Matthes] came up with using red and green light back in 1935, and how [Takuo Aoyagi] (who, along with [Michio Kishi]) figured out the IR and red light part.

The MAX30100 manages to alternate the two LEDs, regulate their brightness, filter line noise out of the readings, and some other tasks. It stores the data in a buffer. The trick is: how do you interpret that buffer?

[Raivis] shows the code to take the output from the buffer, remove the DC component, pass it through a couple of software filters, and detect the heart rate. To read the oxygen reading, you have even more work to do. You can find the code for the device on GitHub.

If you want to build your own without a dedicated IC, grab a clothespin. Or try this more polished build.

Filed under: Arduino Hacks, Medical hacks

[Diego Marino] and his colleagues at the Politecnico di Torino (Polytechnic University of Turin, Italy) designed a prototype that allows for patients with motor deficits, such as spinal cord injury (SCI), to do rehabilitation via Functional Electrical Stimulation. They devised a system that records and interprets muscle signals from the physiotherapist and then stimulates specific muscles, in the patient, via an electro-stimulator.

The acquisition system is based on a BITalino board that records the Surface Electromyography (sEMG) signal from the muscles of the physiotherapist, while they perform a specific exercise designed for the patient’s rehabilitation plan. The BITalino uses Bluetooth to send the data to a PC where the data is properly crunched in Matlab in order to recognize and to isolate the muscular activity patterns.

After that, the signals are ‘replayed’ on the patient using a relay-board connected to a Globus Genesy 600 electro-stimulator. This relay board hack is mostly because the Globus Genesy is not programmable so this was a fast way for them to implement the stimulator. In their video we can see the muscle activation being replayed immediately after the ‘physiotherapist’ performs the movement. It’s clearly a prototype but it does show promising results.

It reminds us of the Myoelectric Hand, with humans instead. We featured an EMG tutorial a while back for those curious about this topic. Without taking the merit out of excellent and needed medical research, we all wait for the day that all our bio-signals can be easy read and translated to, let’s say, a huge avatar robot like METHOD-2. Right? Right?…

Filed under: Arduino Hacks, Medical hacks

What with wearable tech, haptic feedback, implantable devices, and prosthetic limbs, the boundary between man and machine is getting harder and harder to discern. If you’re going to hack in this space, you’re going to need to know a little about electromyography, or the technique of sensing the electrical signals which make muscles fire. This handy tutorial on using an Arduino to capture EMG signals might be just the thing.

In an article written mainly as a tutorial to other physiatrists, [Dr. George Marzloff] covers some ground that will seem very basic to the seasoned hacker, but there are still valuable tidbits there. His tutorial build centers around a MyoWare Muscle Sensor and an Arduino Uno. The muscle sensor has snap connectors for three foam electrodes of the type used for electrocardiography, and outputs a rectified and integrated waveform that represents the envelope of the electrical signal traveling to a muscle. [Dr. Marzloff]’s simple sketch just reads the analog output of the sensor and lights an LED if it detects a muscle contraction, but the sky’s the limit once you have the basic EMG interface. Prosthetic limbs, wearable devices, diagnostic tools, virtual reality — the possibilities are endless.

We’ve seen a few EMG interfaces before, mainly of the homebrew type like this audio recorder recruited for EMG measurements. And be sure to check out [Bil Herd]’s in-depth discussion of digging EMG signals out of the noise.

Filed under: Arduino Hacks, Medical hacks

For most of us, our touch-screen smartphones have become an indispensable accessory. Without thinking we tap and swipe our way through our digital existence, the promise of ubiquitous truly portable computing has finally been delivered.

Smartphones present a problem though to some people with physical impairments. A touchscreen requires manual dexterity on a scale we able-bodied people take for granted, but remains a useless glass slab to someone unable to use their arms.

LipSync is a project that aims to address the problem of smartphone usage for one such group, quadriplegic people. It’s a mouth-operated joystick for the phone’s on-screen cursor, with sip-and-puff vacuum control for simulating actions such as screen taps and the back button.

To the smartphone itself, the device appears as a standard Bluetooth pointing device, while at its business end the joystick and pressure sensor both interface to a Bluetooth module through an Arduino Micro. The EAGLE board and schematic files are available on the project’s page linked above, and there is a GitHub repository for the code.

Technology is such a part of our lives these days, and it’s great to see projects like this bridge the usability gaps for everyone.  Needless to say, it’s a perfect candidate for the Assistive Technology round of the Hackaday Prize.



Filed under: Arduino Hacks, Medical hacks, The Hackaday Prize

Hard as it is to imagine, lie detectors have been sold as children’s toys for a number of years. A simple battery-operated device clipped to your fingers and would show the conductivity of your skin. The concept — which is probably not very reliable — observers that lying causes you to imperceptibly sweat which causes a sudden increase in your skin’s conductivity. These cheap toys would have a meter and you’d note the meter deflection to determine if the subject was lying.

You can debate the amusement value of interrogating your friends, perhaps, but they were pretty common and still exist (including some that shock you if they detect you are lying). Seventeen-year-old [BuildIt] has his own modern take on this classic device using — what else? — an Arduino. You can see a video of the device below.

fvb06bzirsuey29-largeOf interest is how he used the latest version of the Arduino IDE to visualize the data graphically (see right). This is easier than interpreting a bunch of numbers scrolling by on the serial terminal or having to import the data into a spreadsheet. You can find the graph under the Tools menu listed as Serial Plotter.

You don’t need a lot of external parts for this project, although the finger clips and the cardboard box will take a little mechanical skill to complete.

We’ve looked at galvanic skin response and other biosignal processing before. You can do a lot more if you build a little more hardware.

Filed under: Arduino Hacks, Medical hacks

Lots of us get to take home a little e-waste from work once in a while to feed our hacking habits. But some guys have all the luck and score the really good stuff, which is how these robotic surgical tools came to be gesture controlled.

The lucky and resourceful hacker in this case is one [Julien Schuermans], who managed to take home pieces of a multi-million dollar da Vinci Si surgical robot. Before anyone cries “larcency”, [Julien] appears to have come by the hardware legitimately – the wrist units of these robots are consumable parts costing about $2500 each, and are disposed of after 10 procedures. The video below makes it clear how they interface with the robot arm, and how [Julien] brought them to life in his shop. A quartet of Arduino-controlled servos engages drive pins on the wrist and rotates pulleys that move the cables that drive the instruments. A neat trick by itself, but when coupled with the Leap Motion controller, the instruments become gesture controlled. We’re very sure we’d prefer the surgeon’s hands on a physical controller, but the virtual control is surprisingly responsive and looks like a lot of fun.

When we talk about da Vinci around here, it’s usually in reference to 3D printers or a Renaissance-style cryptex build. Unsurprisingly, we haven’t featured many surgical robot hacks – maybe it’s time we started.

[via r/arduino]

Filed under: Arduino Hacks, Medical hacks

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