New Metal Can Become Soft and Stiff Like Human Muscles

inverse.com

20 pointsMurkin3 comments

It's not a new metal! This title is very misleading. They're just balancing a spring against something that contributes negatively to the spring constant that can be added and removed.

Is there a more detailed explanation of this somewhere, and what range of stiffness variation can be achieved?

From what little can be seen in the video, it looks like the main spring is divided in half, and the center plane is variably tensioned perpendicularly, with the leaf springs so acting variably against the lower part of the string.

Prolly gotta read the paper. It relies on something called the beam column effect. It's been used for ages for making vibration isolators. You compress the flexure until you push the resonant frequency where you're happy.

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