A purple 3D-printed case with an LCD screen on the front and Pikachu on top

Avoid Repetitive Strain Injury With Machine Learning – And Pikachu

March 4, 2022 by Robin Kearey 1 Comment

The humble mouse has been an essential part of the desktop computing experience ever since the original Apple Macintosh popularized it in 1984. While mice enabled user-friendly GUIs, thus making computers accessible to more people than ever, they also caused a significant increase in repetitive strain injuries (RSI). Mainly caused by poor posture and stress, RSI can lead to pain, numbness and tingling sensations in the hand and arm, which the user might only notice when it’s too late.

Hoping to catch signs of RSI before it manifests itself, [kutluhan_aktar] built a device that allows him to track mouse fatigue. It does so through two sensors: one that measures galvanic skin response (GSR) and another that performs electromyography (EMG). Together, these two measurements should give an indication of the amount of muscle soreness. The sensor readout circuits are connected to a Wio Terminal, a small ARM Cortex-M4 development board with a 2.4″ LCD.

However, calculating muscle soreness is not as simple as just adding a few numbers together; in fact the link between the sensor data and the muscles’ state of health is complicated enough that [kutluhan] decided to train a TensorFlow artificial neural network (ANN), taking into account observed stress levels collected in real life. The network ran on the Wio while he used the mouse, pressing buttons to indicate the amount of stress he experienced. After a few rounds of training he ended up with a network that reached an accuracy of more than 80%.

[kutluhan] also designed a rather neat 3D printed enclosure to house the sensor readout boards as well as a battery to power the Wio Terminal. Naturally, the case was graced by a 3D rendition of Pikachu on top (get it? a mouse Pokémon that can paralyze its opponents!). We’ve seen [kutluhan]’s fondness for Pokémon-themed projects in his earlier Jigglypuff CO2 sensor.

Although the setup with multiple sensors doesn’t seem too practical for everyday use, the Mouse Fatigue Estimator might be a useful tool to train yourself to keep good posture and avoid stress while using a mouse. If you also use a keyboard (and who doesn’t?), make sure you’re using that correctly as well.

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Avoiding Repetitive Stress Injury: Invest In Yourself Now, Or Pay Later

July 22, 2021 by Kristina Panos 49 Comments

There I was, thirty years after I first sat down at an Apple IIe , and I suddenly found myself wondering if I would ever use a computer again without pain. How could I work if I couldn’t use a computer anymore? I had to seriously ask myself this question. It took a bit of a winding road to figure out what was going on and two EMGs to confirm it, but after all these years, it was clear to the medical community that I had developed a repetitive stress injury (RSI) called cubital tunnel syndrome in my left arm.

Yeah, it’s about like that. Image via Kinesis

Cubital tunnel syndrome is like carpal tunnel, but in your elbow instead of your wrist. What a misnomer! Sometimes my pain went all the way from my armpit to my fingertips and made me want to gnaw my own arm off. I don’t think you can really understand neuropathy unless you’ve felt this weird, annoying type of pain firsthand. I hope you never do.

Can you stop and seriously imagine not being able to use a computer for the rest of your life? Or at least feeling that way because doing so causes incredibly annoying pain? I feel like we’re all vaguely aware of the standard list of anti-RSI precautions, but let’s review:

maintain good posture — sit with feet flat on the floor, wrists straight, elbows at 90°
put the screen an arm’s length away at eye level
take frequent short breaks

Yes, those are all fine and good. But there are other things you can do to avoid computer-related RSIs, like using ergonomic inputs, and building a custom setup that fits you exactly. This isn’t a study kiosk at the university library we’re talking about — this is your battlestation! The problem is that many people are stubborn, and won’t go out of their way to do anything to proactively prevent these injuries. But you don’t have to cross a bridge when you come to it if you have a map that shows you a way around the body of water.

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