Magnus Is a Finger-Drumming, Rapid-Fire, Arduino-Powered Magnetic Exoskeleton for Your Hand

Researchers at the Sony Computer Science Laboratories, the University of Maryland College Park, the University of Tsukuba, and the Okinawa Institute of Science and Technology Graduate University have developed an Arduino-powered exoskeleton designed to deliver faster trigger-finger actuation for anyone looking for an edge in gaming.

"Human-computer integration is an emerging interaction paradigm and has been extended to physical interactions (i.e. a computer physically actuates a user's limbs to perform a task together) by means of motor-based exoskeletons and ones using electrical muscle stimulation," the researchers explain. "While these force-feedback systems demonstrated promising results in motor learning, they face challenges when applied to more timing-sensitive scenarios such as gaming or drumming."

The team's response to this perceived shortcoming: Magnus. Brought to our attention by Arduino, Magnus is a electromagnetic exoskeleton designed to be worn over the user's hand, and delivers actuation at rates in excess of mechanical or muscle-stimulation based alternatives — reaching peak force in as little as 11.7ms, the team claims, compared to 56.4ms for a muscle-stimulating alternative.

The exoskeleton itself is constructed using a selection of electromagnets and permanent magnets, installed in a 3D-printed framework with mechanical linkages. A heatsink bleeds heat from the electromagnet to ensure it can be used as rapidly as possible, while everything is under the control of an Arduino Nano 33 BLE microcontroller board. "The weight of the exoskeleton is 280g [around 9.9oz] with three fingers," the researchers note, "[and] with five fingers, it weighs 452g [around 15.9oz] in total."

The team tested the prototype in two scenarios: a tablet-based finger-drumming game, which required rapid drumming, and a first-person shooting game. "Due to the nature of magnetic actuation," the researchers note, "it provides no pain and excessive fatigue unlike [with] EMS, and has significantly higher backdrivability compared to motor-based actuation systems [as] when the electromagnets are not activated they do not generate additional force."

A short summary of the team's work has been published in the Proceedings of the ACM SIGGRAPH 2024 Emerging Technologies (SIGGRAPH '24), under open-access terms.