Boston Dynamics builds 13-motion hand for Atlas robot

Boston Dynamics has introduced a new four-fingered robotic hand for its electric Atlas humanoid, expanding the hand's capabilities from seven to 13 degrees of freedom. The redesigned hand features four degrees of freedom in the thumb and three in each of the other three fingers, which can also splay. To determine the optimal configuration, the engineering team experimented by taping their own pinky fingers down, ultimately finding that a four-finger setup was sufficient for complex tasks while saving three actuators and reducing mechanical complexity.

The hardware is engineered specifically to support sim-to-real reinforcement learning, where control policies are trained in physics simulators before deployment on physical hardware. To narrow the gap between simulation and reality, Boston Dynamics utilized direct joint actuation without cables, backdrivable transmissions for proprioceptive force sensing, and motor controls that compensate for internal friction and cogging. The hand also features dense tactile pressure sensors on the palm and fingertips, allowing the robot to detect minute contact changes.

For robotics practitioners, this design simplifies the calibration of simulation models and improves the reliability of transferred policies. The hand can perform pinch grasps, tripodal grasps, in-hand reorientation, and operate tools like drills, grinders, nail guns, and welding torches. While the hand uses a single actuator design to ease maintenance, the overall Atlas platform can handle payloads exceeding 100 pounds. Currently, the hand is integrated into the Atlas platform for pilot deployments, with individual pricing and standalone availability not yet disclosed.