Boston Dynamics gives Atlas a four‑fingered hand with no pinky
The new hand has 13 degrees of freedom, up from seven, and an Atlas engineer says a pinky was not worth three extra degrees of freedom of complexity.
Boston Dynamics has replaced the seven-degree-of-freedom hand on its Atlas humanoid with a four-fingered design that has 13 degrees of freedom and no pinky, The Robot Report said on Thursday. The thumb has four degrees of freedom, and each of the three fingers has three.
Dylan Thrush, a mechanical engineer on the Atlas team, said the team judged the extra dexterity of a pinky not worth the complexity of three more degrees of freedom. Chief Product Officer Zachary Jackowski had team members tape their pinkies and ring fingers together for a day, and they concluded the robot did not need one.
The Robot Report described a hand of similar size to a large human hand, driven by direct actuation with a single actuator type and no fragile cables crossing the joints. Dense pressure tactile sensors sit on the fingertips and the palm. The hand can slide its thumb along the other fingers, make pinch grasps and tripodal grasps.
Boston Dynamics says the hand can work tools including drills, torque drivers, grinders, nail guns and welding torches. The design leans on reinforcement learning trained in simulation, and the company said backdrivable actuators let it simulate the hand closely. Boston Dynamics reports promising results moving dynamic tasks from simulation to hardware. The claim is its own and not independently tested.