Using a new kind of robotic joint, researchers at the German Aerospace Center (DLR) have built one of the most robust robotic arms and shoulders ever, the Hand Arm System.

The robotic arm can withstand heavy blows from a baseball bat, continuing to operate as if nothing had happened. The system utilizes shock-absorbing structures called “floating spring joints,” which can vary in stiffness.

The hand includes 38 tendons made of ultra-strong synthetic fiber, each attached to an individual motor. By varying the tension in the tendons, the hand can brace for impact or loosen to perform a delicate manipulation task.

Because of its strength, the Hand Arm System can handle jobs other robots cannot, such as hammering nails into a wooden board.