Radar map has a red sector which indicates the visual
environment of the robot ( the angle of view of camera is about
60 degree, so the red sector means the region our robot can see)
and a blue circle indicates the human face, therefore the red
sector will rotates as the same as the robot neck and the blue
circle will move based on the face size and the x component of
Perr. Ego space projects the surrounding space and object into
the spherical coordinate system centered at the neck of the
robot [7]. The red circle indicates the point where the robot
looks at and blue circle indicates the human face. All these two
windows are developed in the global coordinate. With all of the
information we can realize the dynamic motion of the robot in
any posture.