alt Hacker NewsWe build our living spaces against the constraints of the human form, but that still doesn't imply the human form is optimal for anything. There's no reason a robot traveling over smooth surface should have legs instead of wheels or treads. There's no reason to have a head. Some kind of arm is a common design feature, but certainly no reason to have two. No reason to be symmetrical. A domestic robot may be constrained in terms of scale (ie see things at counter height) but not shape.
Really, the requirements are for the robot to move in predictable ways (if something looks like an arm, it ought to move like an arm, etc), and to have enough strength to be useful for difficult/tiring tasks while somehow also not being dangerous if something does go wrong.