Boston Dynamics gives Atlas a new four fingered hand with 13 degrees of freedom

[MickFoley00]

Boston Dynamics has unveiled a new hand for its Atlas humanoid robot, and it is a big upgrade. Interesting Engineering reports that the new design has 13 degrees of freedom, up from seven on the previous hand. Each finger has three degrees of freedom and the opposable thumb has four, so Atlas can control individual fingertips and spread its fingers. It looks a lot more like a human hand in how it moves. Earlier versions of Atlas used simpler grippers

The hand has pressure sensitive tactile sensors across the fingertips and palm, so Atlas can feel what it is holding. It also uses backdrivable transmissions, meaning outside forces can push the joints back. That sounds like a weakness but it is deliberate, as it lets the robot sense forces through its own joints and react gently. It is also strong, reportedly able to carry a loaded mini fridge weighing over 100 pounds

The most interesting design choice is having four fingers rather than five. Boston Dynamics found that four fingers were enough for reorienting objects in the hand, recovering from slips and using tools. Adding a little finger would need three more actuators, adding cost, size and more things that can break. For an industrial robot that has to work reliably all day, fewer parts is better

The hand was designed with simulation in mind. Boston Dynamics says it was optimised for high fidelity simulation and reinforcement learning, so behaviours trained in a virtual world transfer to the real robot. That is how most robotics companies now train new skills, and hardware that is easy to simulate accurately makes the process much faster. It keeps the hand human sized too, so it can use normal tools

Atlas is being developed for real factory work with Hyundai at a facility in Georgia, focused on logistics and assembly. The four finger decision is the kind of practical engineering choice I like to see. Would a missing little finger bother you in a robot? And how long before humanoids like this are common in factories?

Boston Dynamics unveils 13-DOF robotic hand for its Atlas humanoidinterestingengineering.com