The human shape is not efficient, it is compatible. A wheeled robot needs ramps and clear floors; a humanoid can in principle use the same doors, ladders, hand tools and workbenches as the staff around it.
Technically a humanoid is a hard balance problem with dozens of degrees of freedom. It needs powerful, backdrivable joints, an inertial measurement unit, force sensing in the feet and a controller that reacts within milliseconds to stay upright. Battery runtime and hand dexterity are the usual practical limits.
Current activity centres on pilot deployments in warehouses and car plants, with platforms such as Agility Digit, Figure and Tesla Optimus, and on general-purpose control models trained from teleoperated demonstrations.
