How does a Humanoid Robot work?

What you are asking is a monumental task. Every function of the robot must be designed, tested and miniaturized.

Robotic engineers have been working on a humanoid robot that can simply walk in a way that we consider to be normal for humans. Balance is a difficult process.

While a humanoid robot is simply motors, servo's, sensors and computer components, they must be integrated into a functioning whole to make a device that can be called a humanoid robot.