I'm no robotics engineer, but to me the design looks brilliant. I suspect that the biggest problem with a machine that needs to pick up and carry objects in a

I'm no robotics engineer, but to me the design looks brilliant. I suspect that the biggest problem with a machine that needs to pick up and carry objects in a somewhat humanoid fashion is going to be weight and balance. They've attacked the problem by making the entire body of the robot a seesaw and adjustable counterweight to control the balance. Having the robot on two wheels also gives the robot a smaller footprint, gives it a zero turn radius, simplifies how you control turning, and probably also simplifies the navigation control algorithms.