CNS for Long Range Unmanned Surface Vessels

Long-Range Unmanned Surface Vessels (LRUSV) are designed to operate for several days at ranges up to 1,000 nautical miles in Sea State 4 conditions. During hostilities LRUSVs cannot rely on GPS. Trex is developing a Celestial Navigation System (CNS), which operates based on the patented Angles-Only Navigation Method and does not require knowledge of the gravity vector for position determination. ĀCNS provides high accuracy (25m) position updates to the onboard INS both day and night, including during the ōMidnight Hole,ö because drifts and biases of the INS and Schuller oscillation do not affect CNS position accuracy. The update rate is once every 5 minutes.Ā During daytime and terminator, CNS images LEO satellites and during the ōMidnight Hole,ö it tracks GPS satellites. CNS has a small topside volume of 0.036m3 and 2 computer slots below deck suitable for a 40-foot boat.Ā In the Phase-II program, prototype optical, mechanical, electrical, and software designs will be developed. CNS optical payload and electronic components will be assembled and integrated into the gyro-stabilized gimbal, SF-280. Celestial Navigation algorithms will be refined, real-time software will be developed, prototype software and hardware will be integrated. Static and dynamic moving vehicle tests on land will be performed followed by an on-boat at-sea demonstration.