System for Avoidance and Flight-path Execution based on Risk Reduction (SAFERR)

Finding ways of safely and securely traversing autonomous aerial vehicles (AAV) through urban environments is key to the advanced/urban air mobility problem (A/UAM). In the urban setting, there is no AAV flight that has zero risk. Currently, traversing urban environments is difficult for military operators and nearly impossible for commercial operators. Military operators are often treated as manned traffic by air traffic controllers while commercial operators are typically not allowed to traverse urban environments except in highly restricted and controlled cases. Additionally, while a mission can be planned based on known risk, new risks can emerge during a flight that will require a UAV or operator response. This includes events like natural disasters, public safety emergencies, terrorist attacks, or degradation in the AAV’s nominal operability. These emergent risks present difficult challenges to A/UAM flights because of the heightened risk due to congested airspaces and the potential of striking populated areas when failures occur.  To mitigate these risks, the System for Avoidance and Flight-path Execution based on Risk Reduction (SAFERR) is proposed. SAFERR addresses risk mitigation for flight planning and mission execution. The system generates flight path of acceptable risk using known factors like population density, land use, and weather patterns. SAFERR then provides real-time path augmentation as new emergent risk is identified or the AAV experiences malfunctions or conditions that degrade performance. Once AAV system degradations are observed, reachability analyses are performed with adapted control policies to provides information on where the AAV can go and how it gets there. Emergent risks are identified, assessed for severity, and feasible paths from the reachability analysis are scored against these identified risks. Augmented paths are then selected based on those that have low risk and are safe according to the reachability analysis SAFERR will advance the current state-of-the-art by providing safety critical flight planning and mission execution in real time, by avoiding and mitigating emergent risk situations, and by augmenting existing flight plans to ensure safety is maintained and missions are completed if possible.