Hugh Herr and his crew at the MIT Media Lab are making serious headway on a new interface to connect bodies to prosthetic devices. The technology’s label—magnetomicrometry—sounds unwieldy, but the solution itself is downright feathery. It’s based on small magnetic implants that measure muscle activity in the residual limb and can transmit the corresponding intent to the prosthesis.
That job is routinely performed by myoelectric sensors in present devices, but the magnets can read muscle movements with far greater precision. When a muscle contracts, the beads get closer together; when it relaxes, they slide further apart. An external sensing device continuously monitors these signals and translates them into action, creating an intuitive interface that closely mimics natural limb movement.
“I am very excited for the clinical potential of this new technology to improve the control and efficacy of bionic limbs for persons with limb loss,” Herr told MIT News.
Although the system hasn’t been tested in humans yet, it has been validated in animal-based trials. In addition to providing reliably accurate measurements of muscle length and velocity, the magnetic implants didn’t cause scarring, inflammation, or other tissue damage.
The research team, which also includes scholars from Harvard Medical School and Brown University, plans to test the system in humans as soon as the FDA grants approval. In addition to evaluating micromagnetometry’s potential for neuroprosthetic control, these tests may also yield data about the technology’s effects on proprioception, robotic limbs, and exoskeletons.