초록 ▼

A scanning and/or tracking mechanism for use in airborne obstacle avoidance optical radars operating in the infrared 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 infrared radi

A scanning and/or tracking mechanism for use in airborne obstacle avoidance optical radars operating in the infrared 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 infrared 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.

대표청구항 ▼

A scanner/tracker for an optical radar set, comprising a pair of spaced axially aligned circular rotatable optical wedges which rotate around the boresight axis of said optical radar, motor means for separately driving each of said wedges , each motor means including a rotatable hollow shaft with sa

A scanner/tracker for an optical radar set, comprising a pair of spaced axially aligned circular rotatable optical wedges which rotate around the boresight axis of said optical radar, motor means for separately driving each of said wedges , each motor means including a rotatable hollow shaft with said wedges mounted within said hollow shafts to rotate therewith, an incremental shaft position encoder including a circular encoder disc extending radially outward of each said shaft, each disc being directly and coaxially attached to each said wedge and being rotatable therewith, each disc including a peripheral circular track of alternating transparent and opaque uniformly spaced coding segments, a modulated light source remote from said scanner/tracker, a stationary fiber optic bundle including a plurality of joined parallel optical fibers having a common end face arranged to convey light from said source to one side of said circular disc coding segments, and a second like stationary fiber optic bundle having an opposing end face on the opposite side of said encoder disc to receive said light transmitted through said transparent disc segments, said opposing end face including a stationary mask having opaque segments of varying dimensions secured thereto, and decoding circuitry means for determining the angular position and direction of rotation of said wedges by sensing the light passed through said rotatable disc segments and stationary mask.