Elon Musk wrangles with the robot hand

Tesla CEO Elon Musk revealed that the company is striving to design a sturdy human hand for its Optimus robot. The robotics industry faces a significant challenge in creating such a hand, as demonstrated by Musk's statement that constructing the motor skills for the humanoid hand is "shockingly difficult."

Musk has yet to witness a robot hand capable of screwing in a self-tapping screw, a seemingly simple task for humans. He questioned whether boxing robots could perform such a basic action, highlighting the complexity of the problem. Designs for human-like robot hands are considered one of the most difficult engineering challenges within the robotics industry.

Musk emphasized the difficulty in replicating human-like fine motor skills, such as screwing a nail or opening a jar of pickles, with robot hands. These skills require the appropriate application of force, precision, and sensors. Despite the efforts of various robotics companies, no standard design for a human hand in robots has been established. Key design decisions include motor placement and sensor selection, both of which have trade-offs.

The placement of motors—either directly in the hands or within the arms—results in smaller motors that may break more easily and produce less force. Placing sensors too close to the surface can lead to damage, while touch sensors that can elastically deform and maintain high cycle life are challenging to create. Some robotics firms have chosen not to replicate the human hand, while others continue to work on solving this complex problem.