PROGRAMMABLE SCANNER/TRACKER

摘要

A scanning and/or tracking mechanism for use in airborne obstacle avoidance optical radars operating in the infra-red region. The radar beam is scanned by passing it through a pair of in-line rotating optical wedges which rotate around the boresight axis and which are transparent to the infra-red radiation. The wedges are separately driven by servo systems including hollow shaft torque motors with the wedges mounted in the hollow shafts thereof. A high resolution and low backlash shaft position encoder is utilized comprising encoding discs directly driven by the optical wedges and including a novel decoding system.