UAV Application of IBLS for Autonomous Takeoff and Landing

This paper discusses the use of the Integrity Beacon Landing System (IBLS) for use as the principal position sensor for Unmanned Aerial Vehicle (UAV) systems. IBLS augments orbital GPS satellites with ground based Integrity Beacons to provide almost instantaneous centimeter-level accuracy and high integrity during landing approach, flare and rollout. Integrity Beacons are low-power, ground-based pseudolites that transmit a GPS-like signal that is measurable only inside a “bubble” emanating from the beacon’s transmit antenna. This paper discusses two of many possible system configurations, one tailored to land-based and one to ship-based UAV operations. The airborne and ground system components are discussed and flight test results from the INAV-T test aircraft. For automatic takeoff and landing of UAV’s, centimeter level accuracy and sensor integrity are critical to achieving reliable and safe operation on land or at sea. To address these requirements, IBLS is unique in its combination of: · Instantaneous centimeter-level accuracy · Bulletproof integrity · All weather land- or ship-based operation · Light weight and ease of transportation · Fast setup with minimal training requirements · Proven UAV autoland performance GPS Receive Data Link (shared) Reference GPS Receiver/ mP Integrity Beacon Integrity Beacon Data Link Transmitter Aircraft GPS Receiver Integrity Processor IRU Attitude Aircraft GPS Receiver Data Link Receiver Real Time Position (to Autopilot) GPS Receive Integrity Beacon Ranging Aircraft Ground System Attitude Receiver (Also could be IRU) 4 GPS antennas not shown for attitude receiver Figure 1. IBLS block diagram