The video starts with a simple demonstration, showing that a Lego universal joint pops apart at just 0.4 Nm of torque. It’s no surprise, given it relies on tiny plastic pins in snap-fit joints.

It’s extremely similar to the pneumatic LEGO, but more precise and much more lifelike. The system uses a pair of cylinders on each joint of a robot. Disney is using a rolling diaphragm to seal ...