Boston Dynamics' Atlas Gets a Four-Fingered Hand

Fewer fingers, 13 identical actuators, and a design philosophy built around reliability over complexity.

By The Robotics Desk

Boston Dynamics has revealed a redesigned hand for its Atlas humanoid — four fingers, 13 degrees of freedom, and no pinky. [1]

The new hand is built from 13 identical actuators, all fully encapsulated, with no fragile cables crossing joints. Rodriguez noted that the earlier hands were strong enough to lift 100 lb.-plus heavy objects, so the team did not need to increase strength and could consider decreasing it a bit to further improve actuation transparency. [1]

Alberto Rodriguez, the director of robot behavior for Atlas at Boston Dynamics, said the design was shaped by a clear product roadmap — one that forced hard calls on dexterity, cost, ruggedness, and reparability. The team considered a hand with two thumbs, one on each side, which would have allowed a single assembly line for left and right variants, but ultimately rejected it because of the extra degrees of freedom, cost, and added volume it required. [1]

The hand was also built for high-fidelity simulation from the ground up, enabling sim-to-real reinforcement learning. [1]

The hand question has always been the hardest one in humanoid robotics — the place where ambition meets assembly line. Boston Dynamics' answer is, characteristically, to make reliability the feature.

The new hands have been tested extensively at Boston Dynamics' headquarters but have not yet been deployed to the whole robot fleet, with Rodriguez citing the coordination and time required to make sure it does not disrupt regular operations like data collection or applications. [1]

Build actuators that simulate well, and then rely on RL at scale.Alberto Rodriguez