Patent ID: 8243142
Filing Date: 2012-08-14
Classification: G01S,H04N

Abstract:
1. A mobile object image tracking apparatus comprising: at least one rotary unit configured to rotate about at least one axis; a camera sensor configured to photograph a mobile object to acquire image data, the camera sensor being supported by the rotary unit; a first detection unit configured to detect a tracking error as a tracking error detection value, based on the image data, the tracking error being a deviation from a center of a field of view of the camera sensor; a second detection unit configured to detect an angle of the rotary unit; an estimation unit configured to estimate the tracking error as a tracking error estimation value, using the angle and a temporal differentiation value of the angle; a selection unit configured to select the tracking error detection value when the mobile object falls within the field of view, and to select the tracking error estimation value when the mobile object falls outside the field of view; wherein the selection unit compares the tracking error detection value with the tracking error estimation value, and adjusts the tracking error estimation value to match an amplitude of the tracking error estimation value with an amplitude of the tracking error detection value; a computation unit configured to compute an angular velocity instruction value used to drive the rotary unit to track the mobile object, based on the angle and a selected one of the tracking error detection value and the tracking error estimation value; a third detection unit configured to detect an angular velocity of the rotary unit; and a control unit configured to control the rotary unit to make zero a difference between the angular velocity instruction value and the angular velocity.