Motor-free fiber muscles bring silent, human-like movement to modern robots

Researchers at MIT Media Lab and Politecnico di Bari developed artificial muscle fibers.

The electrofluidic fiber muscles are electrically driven actuators in a fiber format.

The design combines a thin McKibben actuator with a miniaturized solid-state pump.

Millimeter-scale pumps are embedded in the fibers; charged dielectric fluid creates pressure without moving parts.

Opposing fiber pairs let one contract while the other extends in a closed loop, removing the need for an external reservoir. The lightweight system can run silently, but it must stay pre-pressurized to avoid cavitation.