초록 ▼

A system for maneuvering an aircraft for operations in connection with a sea-going vessel, the vessel having a designated area for landings and sling-load operations. Each of the aircraft has a navigation unit (INU) comprising a GPS receiver and an inertial navigation unit. The INU's are updated by

A system for maneuvering an aircraft for operations in connection with a sea-going vessel, the vessel having a designated area for landings and sling-load operations. Each of the aircraft has a navigation unit (INU) comprising a GPS receiver and an inertial navigation unit. The INU's are updated by data from the GPS receivers and the data from the shipboard unit's GPS receiver and INU are transmitted to the aircraft. The aircraft performs RTK calculations to determine a vector to the shipboard GPS antennas and modifies the vector with data from the INU's.

대표청구항 ▼

1. A system for positioning an aircraft relative to a designated location on an ocean-going vessel, the system comprising: A. a shipboard navigation unit comprising: 1. a first GPS antenna,2. a first GPS receiver for processing signals from the first GPS antenna,3. a first inertial navigation unit (

1. A system for positioning an aircraft relative to a designated location on an ocean-going vessel, the system comprising: A. a shipboard navigation unit comprising: 1. a first GPS antenna,2. a first GPS receiver for processing signals from the first GPS antenna,3. a first inertial navigation unit (INU) configured to receive periodically updated data generated by said first GPS receiver, at a rate that minimizes INU error;4. a transmitter for transmitting over a wireless link, shipboard GPS data and INU data;B. an aircraft-based navigation unit comprising: 1. a second GPS antenna,2. a second GPS receiver for processing signals received from the second GPS antenna,3. a second INU configured to receive periodically updated data based on updated data from the first INU and an RTK moving baseline vector determined using data from the first and second GPS receivers, with the data from the first and second GPS receivers, the updated data from the first INU and the RTK moving baseline vector all having a same time tag,4. a receiver for receiving signals from said shipboard navigation unit, said signals being transmitted over the link by the transmitter,5. an RTK arrangement configured to generate the RTK moving baseline vector from the first GPS antenna to the second GPS antenna, said RTK arrangement further configured fordetermining a post-update correction vector for the RTK baseline vector based on post-update first INS and second INS position information and using the post-update correction vector to determine a post-update inertial position correction; and6. the aircraft INU further configured to update its output with the post-update inertial position correction and to compute a position vector of high accuracy from the aircraft INU to a designated location on the vessel. 2. The system defined in claim 1 wherein the shipboard navigation unit is further configured for generating a second vector from the first GPS antenna to the designated location, and transmitting the data for generating said second vector to the aircraft which generates a position vector from the aircraft to a landing pad. 3. The system defined in claim 2 including a Kalman filter that is configured to update the parameters of the second inertial unit. 4. The system of claim 1 wherein the output position of the aircraft navigation unit is calculated using a Kalman filter. 5. The system of claim 4 wherein the aircraft navigation unit is configured to correct the output position of the inertial system in the aircraft using the post-update inertial position correction to restore relative accuracy between the shipboard system and the aircraft system. 6. The system of claim 5 wherein the aircraft navigation unit is configured to compute said post-update inertial position correction by differencing a post-update position of the vessel and a post-update position of the aircraft, and subtracting this difference from said RTK moving baseline vector. 7. The system of claim 1 wherein the RTK moving baseline vector between the vessel and the aircraft is calculated using actual measurements that correspond to the same time tag at the second receiver and the first receiver, respectively. 8. The system of claim 7 wherein the aircraft navigation unit is configured to update a Kalman filter at a time that accommodates latency in the calculated measurements. 9. The system of claim 8 wherein the aircraft navigation unit is configured to update the Kalman filter to ensure said measurements have the same time tag. 10. The system of claim 1 wherein the aircraft navigation unit is configured to utilize the RTK moving baseline vector to determine an accurate position relative to said first GPS antenna onboard said vessel. 11. The system of claim 1 wherein a computer on the aircraft is configured to compare inertial navigation unit position data on the aircraft to inertial navigation unit position data transmitted to the aircraft from the vessel, to determine a low latency distance from and bearing to the GPS antenna on board said vessel from the aircraft. 12. The system of claim 1 wherein said navigation system on board said vessel is further configured to calculate information including parameters of a vector from the first GPS antenna to designated location, which is a landing pad. 13. The system of claim 12 wherein said information is transmitted over said wireless link from the vessel to the aircraft. 14. The system of claim 13 wherein the aircraft uses said information to provide the aircraft with a vector to a landing pad on the vessel. 15. A system for positioning an aircraft relative to a designated location on an ocean-going vessel, the system comprising: A. on the vessel, a navigation unit including: 1. a first GPS receiver configured to receive and process signals received over a first GPS antenna, thereby to provide periodic position data;2. a first inertial navigation unit (INU) configured to received periodically updated data generated by said first GPS receiver at a rate that minimizes INU error, relating to the position of the vessel;3. a transmitter that transmits over a wireless link to an associated aircraft, the position data generated by the first GPS receiver and the first INU; andB. in the aircraft, a navigation unit including: 1 a second GPS receiver configured for receiving and processing GPS signals received over a second GPS antenna,2. a second INU having an output that is updated in accordance with periodically updated data that are based on updated data from the first INU and an RTK moving baseline vector determined using data from the first and second GPS receivers, the updated data from the first INU and the RTK moving baseline vector being associated with times at which measurements are available at the GPS receivers,3. a receiver adapted to receive signals transmitted over the wireless link by the transmitter in the navigation unit on the vessel,4. an RTK arrangement configured to process the GPS data to generate the RTK moving baseline vector from the second antenna to the first antenna, and said RTK arrangement being further configured for differencing a post-update remote position at the aircraft based on second INS data with a post-update base station position on the ship based on first INS data to produce a correction vector and subtracting the correction vector from the RTK moving baseline vector to obtain a post-update inertial position correction, and5. the aircraft INU being further configured to update its output with said post-update inertial position correction and to compute a position vector of high accuracy to guide the aircraft for landing at a designated location on the vessel. 16. The system of claim 15 further comprising: said navigation unit on said aircraft being further configured for comparing inertial navigation unit position data on the aircraft to inertial navigation unit position data transmitted to the aircraft from the vessel, to determine a low latency distance from and bearing to the GPS antenna on board said vessel from the aircraft. 17. The system of claim 15 wherein said aircraft comprises a helicopter. 18. The system of claim 15 wherein the designated location is a landing pad,said navigation system on board said vessel is further configured to calculate information including parameters of a vector from the first GPS antenna to the landing pad, andsaid aircraft navigation system uses the parameters to guide the aircraft to the landing pad. 19. A system comprising on a ship, a first navigation unit comprising: a first satellite signal receiver that processes signals received by a first antenna;a first inertial navigation unit (INU) that is updated using data that are provided by the first satellite signal receiver and associated with a given time tag;a transmitter for transmitting satellite signal and INU information;on an aircraft, a second navigation unit comprising: a second satellite signal receiver that process signals received by a second antenna;an RTK sub-system configured to use data from the first and second satellite receivers to determine an RTK moving baseline vector between the first antenna and the second antenna, the RTK moving base line vector being associated with the given time tag;a second INU that is periodically updated based on the RTK moving baseline vector and the updated data from the first INU; andone or more processors configured to produce a post-update inertial position correction based a correction calculated for the RTK moving baseline vector using post-update data from the first and second INUs, and to update the output position of the second navigation unit with the post-update inertial position correction to restore relative accuracy between the shipboard and the aircraft navigation units and produce a corrected relative aircraft position. 20. The system of claim 19 further including in the first navigation unit, one or more processors configured to produce a vector from the first antenna to a predetermined landing pad; andin the second navigation unit, one or more processors configured to determine a vector from the corrected position of the aircraft to the landing pad based on the vector from the first antenna to the landing pad. 21. The system of claim 20 wherein the post-update inertial position correction is determined by differencing a post-update position of the aircraft that is based on data from the second INU with a post-update position of the vessel that is based on data from the first INU to obtain a second vector that is the correction for the RTK moving baseline vector, andsubtracting the second vector from the RTK moving baseline vector. 22. A navigation system consisting of a ship navigation subsystem including a first GPS receiver and associated first GPS antenna, the first GPS receiver periodically determining GPS position data relating to the first GPS antenna;a first INU configured to use the position data determined by the first GPS receiver to update inertial positions and between updates determines post update inertial positions based on INU sensor data;a transmitter that transmits the GPS position data and the inertial positions to a remote navigation subsystem;the remote navigation subsystem including a second GPS receiver and associated second GPS antenna, the second GPS receiver periodically determining GPS position data relating to the second GPS antenna;an RTK processor configured to use the GPS position data determined by the first and second GPS receivers to determine enhanced positions of the second GPS antenna and associated baseline vectors between the first and second GPS antennas;a second INU configured to use the enhanced positions to update inertial positions and between updates determine post-update inertial positions based on INU sensor data;the RTK processor further configured to determine a baseline correction vector based on the post-update inertial positions of the first and second GPS antennas, the RTK processor configured to use the baseline correction vector to correct the post-update positions determined by the second INU.