Target-Tracking Camera for a Metrology System

Angular measurements are updated at a rate of hundreds of hertz.

NASA’s Jet Propulsion Laboratory, Pasadena, California

An analog electronic camera that is part of a metrology system measures the varying direction to a light-emitting diode that serves as a bright point target. In the original application for which the camera was developed, the metrological system is used to determine the varying relative positions of radiating elements of an airborne synthetic-aperture-radar (SAR) antenna as the airplane flexes during flight; precise knowledge of the relative positions as a function of time is needed for processing SAR readings.