Halloween may be behind us, but The Nightmare Before Christmas proved you can combine the spooky holiday with the “Most Wonderful Time of the Year” to get some fabulous music. With that in mind, we present a robot hand, shaped like a human skeleton’s, that can play jingle bells:
Credit: Josie Hughes
To paraphrase a Russian proverb, the marvel is not that the robot skeleton hand plays well, but that the robot skeleton hand plays at all. It’s the latest work from a robotics lab at the University of Cambridge, and it’s more significant than it might at first appear.
Gotta Robot Hand It To ’em
The new robot hand, described today in Science Robotics, recreates the most important human structures south of the wrist: bones and ligaments. The thing effectively has joints with adjustable stiffness, resulting in a device that can play various types of musical notes solely through “passive” dynamics — the fingers themselves don’t move, but they react differently based on the conditions they encounter.
Basically, the robot hand only moves at the wrist and arm level, whose motor skills are provided by a standard robot arm attachment. The skeletal fingers react to the piano keys differently, depending on their joints’ stiffness and how they’re placed on the keys. So this single hand design, 3-D printed in one go with various materials, can play various musical styles: a staccato single-finger technique, a Fats Waller inspired crawling baseline and a glissando the researchers charitably call the opening of George Gershwin’s Rhapsody in Blue.
Credit: Josie Hughes
Today Piano, Tomorrow the World
This variety from a single passive system — simpler and more energy efficient than a system that powers each individual finger — is why we can forgive the robot hand’s finger fumbles. A different system might be more accurate with individual notes, but this one is more versatile, and capable of much subtler movements. “This approach allowed the printing of a passive anthropomorphic hand that provided the ability to reproduce complex human hand capabilities,” the authors write, “and to show hand behaviors that cannot be performed by other conventional robots.”
Ultimately, piano playing is just a stand-in for any sufficiently advanced display of human dexterity. It’s technology with obvious practical applications, from improved designs for prosthetics (including, yes, hand design) to uses for any industry that needs delicate control over automated processes, such as manufacturing or storage. And, as the authors point out, their research can even help biologists better understand animal anatomy “by building bioinspired robotics that explore biological design and function.”
So let’s cut the robot hand some slack on the piano. We just have to give the technology time to develop — as any good musician knows, the only way to improve is to practice, practice, practice.