Patent ID: 8279430
Filing Date: 2012-10-02
Classification: G01C,G01S

Abstract:
1. A tracking method, comprising the steps of, tracking a target point provided with a reflector by a measurement beam of a laser tracker, in an ordinary tracking mode, deriving data for controlling the direction of the measurement beam from the detection of the measurement beam being reflected by the reflector, and automatically activating an extraordinary tracking mode as soon as no reflected measurement beam is detected by the laser tracker; in the extraordinary tracking mode, wherein the extraordinary tracking mode is active when no measurement beam reflected by the reflector is detected, computing the data for controlling the direction of the measurement beam from a direction to the target point being determined from image data registered by an overview camera and from a known position and orientation of the overview camera relative to the measurement beam, wherein the direction of the optical axis of the overview apparatus is coupled to the direction of the measurement beam in a fixed manner, in the extraordinary tracking mode, the laser tracker monitoring detection of the reflected measurement beam, and automatically activating the ordinary tracking mode as soon as the reflected measurement beam is detected.