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EMERGING TECH | XR & AR
Wrist power: the future of computer control might be in our muscles
sEMG is the new companion technology redefining interaction with all types of digital devices
Surface Electromyography (sEMG) technology has been gaining significant attention in recent years due to its potential to revolutionize various fields, including healthcare, sports, and human-computer interaction.
If you haven’t heard of sEMG yet, hopefully this article can help explore its principles, applications, and resources.
What is Surface Electromyography (sEMG) Technology?
Surface Electromyography (sEMG) is a non-invasive technique used to measure the electrical activity of muscles. It involves placing electrodes on the skin surface to detect the electrical signals generated by muscle fibers during contraction. These signals are then amplified, processed, and analyzed to provide valuable information about muscle function, activity, and fatigue.
Basically, we can use our body movements, gestures and even micro-movements) as input to a digital device.
Why is it relevant in our immediate future?
The Problem
The development of novel computing devices, such as AI-enabled and augmented reality (AR) glasses, has introduced a new challenge for product designers and consumers alike when it comes to controlling these devices.
How can users seamlessly provide inputs when traditional input devices, like a keyboard and mouse or a touchscreen, are not readily available and do not work while “on-the-go”?
The Joe Rogan’s podcast with Mark Zuckerberg sparked conversations about the “Jack in the head VS wristband” future scenarios. You can listen to this specific conversation below or clicking here.
We basically found that doesn’t do input to you but it’s good for giving you the ability to control a computer, because basically you have all these extra neurons that go from your brain to controlling your hand.
I’m like going to be able to text my wife or friends or something or text AI and get an answer to something. Like I forgot something while we were talking, let me just text AI, okay I just did that sitting, totally discreet and the answer just comes into your glasses.
The Possible Solution
An sEMG wristband addresses the challenge above by enabling a person to interact with computing devices using various hand gestures, like swiping their thumb to scroll through songs on a playlist while walking around outside.
This is possible since sEMG technology can reliably identify hand gestures based on muscle activity detected from sensors on the surface of the skin near the wrist. This wrist-wearable technology allows people to use computing devices with minimal friction anywhere, because sEMG enables users to provide inputs without manipulating a touchscreen or another physical input device.
The State-of-the-Art
While Ray-Ban Meta opened up an entirely new category of display-less glasses super-charged by AI, the XR industry has been disrupted by the launch of Orion in October 2024. These true AR glasses combine the benefits of a large holographic display with personalized AI assistance in a comfortable, stylish, all-day wearable form factor.
Orion’s input system combines voice, eye gaze, and hand tracking with an EMG wristband that lets you swipe, click, and scroll while keeping the user’s arm resting comfortably by their side, letting them stay present in the world and with the people around them as they interact with rich digital content.
How does it Work?
Curious to learn more? I recommend reading Meta Reality Labs’ latest white paper about sEMG.
When a person flexes their finger, a part of the brain called the motor cortex sends signals to the spinal cord, which in turn sends electrical signals to the muscles through spinal motor neurons. These motor neurons cause muscle fibers to contract and create muscle forces and movements. Sensors placed on the surface of the skin can observe the electrical signals that produce muscle contraction, allowing an sEMG device to detect when a user is controlling the muscles in their arm.
This is conceptually similar to detecting a finger movement using a keyboard, but instead relies on sensing the electrical signals generated by the muscle rather than detecting the movement of a key. Muscle signals can be detected even when the movements are subtle or when a surface provides an opposing force that prevents movement.
One of the aspect I appreciate the most about this technology are the implications for accessibility.
Since movement is not required for sensing, sEMG has great potential as an inclusive technology that works for users with a broad range of physical abilities. A person who is unable to move in a typical way due to injury or a movement disorder could more easily control a device with sEMG than with a traditional controller like a keyboard.
Importantly, sEMG can only detect when someone activates their muscles — it is not capable of observing a user’s brain activity or reading their “inner thoughts.”
Where else can sEMG Technology help?
The applications of sEMG technology are diverse and rapidly expanding. Some of the most promising areas include:
- Rehabilitation and Physical Therapy: sEMG can help clinicians assess muscle function, monitor progress, and develop personalized treatment plans for patients with musculoskeletal disorders or injuries.
- Sports Performance and Injury Prevention: By analyzing muscle activity patterns, athletes and coaches can optimize training programs, reduce the risk of injury, and enhance overall performance.
- Prosthetics and Orthotics: sEMG can be used to control prosthetic limbs, enabling individuals with amputations to regain motor function and independence.
- Neurological Disorders: sEMG may aid in the diagnosis and monitoring of conditions such as Parkinson’s disease, amyotrophic lateral sclerosis (ALS), and muscular dystrophy.
Conclusion
Like the touchscreens, mice, and keyboards that came before, an Human-to-Computer interface based on sEMG at the wrist can reshape our interaction with physical and digital systems by offering people a safe, seamless, and user-action focused method to control their digital devices.
Additional Resources
For those interested in exploring sEMG technology further, here are some resources to get you started:
- International Society of Electrophysiology and Kinesiology (ISEK): A professional organization dedicated to promoting research and education in electrophysiology and kinesiology.
- IEEE Engineering in Medicine and Biology Society (EMBS): A community of engineers, scientists, and clinicians working on innovative solutions for healthcare and biomedical applications.
- ResearchGate: A social networking platform for scientists and researchers, featuring publications, projects, and discussions related to sEMG technology.
- Inside Facebook Reality Labs: Wrist-based interaction for the next computing platform.
