Robust Navigation in GPS-Denied Environments

GPS-denied navigation capabilities are critical for ensuring safe low-altitude flight operations and enabling autonomous Unmanned Aerial System (UAS) operations. This capability can be directly integrated with an existing UAS or full-scale helicopter to support Air Force Special Operations Command (AFSOC) operations in environments prone to GPS outages. Furthermore, autonomous unmanned aircraft cargo delivery systems increase logistics safety, speed, and efficiency. Such capabilities can be leveraged to support US military assistance to civilian agencies in remote areas. Additionally, the Near Earth system can be used in conjunction with a UAS to rapidly deliver critical supplies to downed pilots during Personnel Recovery (PR) efforts. Near Earth Autonomy has developed robust state estimation and aircraft autonomy with an eye to high-performance military and commercial systems. Near Earth’s robust autonomy capability ensures continuous operation with multiple measurement modalities, in particular, reliable autonomy with intermittent GPS. The solution proposed here is an autonomy package that maintains guidance, navigation, & control (perception, planning, & control) despite the drift, noise, and jumps of GPS-intermittent state estimation. This solution provides a key capability for low-flying rotorcraft and unmanned aerial systems (UAS) to be able to operate safely when positioning from GPS is degraded, such as when line of sight to GPS satellites is occluded (as when operating close to terrain features and man-made structures) or GPS signals are intentionally blocked.