# Acoustic tractor beams let researchers remotely program material stiffness

- slug: acoustic-tractor-beams-let-researchers-remotely-program-material-stiffness
- date: 2026-03-22
- category: Robotics

There is a problem at the center of soft robotics that nobody has fully solved: how do you make something that is simultaneously safe enough to be near a human and rigid enough to do useful work? The usual answers — pneumatic bladders, vacuum-jammed granular packets, heated shape-memory alloys — ...

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