Sense and Avoid Characterization of the Independent Configurable Architecture for Reliable Operations of Unmanned Systems

AbstractIndependent Configurable Architecture for Reliable Operations of Unmanned Systems (ICAROUS) is a distributed software architecture developed by NASA Langley Research Center to enable safe autonomous UAS operations. ICAROUS consists of a collection formally verified core algorithms for path planning, traffic avoidance, geofence handling, and decision making that interface with an autopilot system through a publisher-subscriber middleware. The ICAROUS Sense and Avoid Characterization (ISAAC) test was designed to evaluate the performance of the onboard Sense and Avoid (SAA) capability to detect potential conflicts with other aircraft and autonomously maneuver to avoid collisions, while remaining within the airspace boundaries of the mission. The ISAAC tests evaluated the impact of separation distances and alerting times on SAA performance. A preliminary analysis of the effects of each parameter on key measures of performance is conducted, informing the choice of appropriate parameter values for different small Unmanned Aircraft Systems (sUAS) applications. Furthermore, low-power Automatic Dependent Surveillance Broadcast (ADS-B) is evaluated for potential use to enable autonomous sUAS to sUAS deconflictions as well as to provide usable warnings for manned aircraft without saturating the frequency spectrum

Performance Analysis Of Automatic Dependent Surveillance-Broadcast (ADS-B) And Breakdown Of Anomalies

This thesis work analyzes the performance of Automatic Dependent Surveillance-Broadcast (ADS-B) data received from Grand Forks International Airport, detects anomalies in the data and quantifies the associated potential risk. This work also assesses severity associated anomalous data in Detect and Avoid (DAA) for Unmanned Aircraft System (UAS). The received data were raw and archived in GDL-90 format. A python module is developed to parse the raw data into readable data in a .csv file. The anomaly detection algorithm is based on Federal Aviation Administration\u27s (FAA) ADS-B performance assessment report. An extensive study is carried out on two main types of anomalies, namely dropouts and altitude deviations. A dropout is considered when the update rate exceeds three seconds. Dropouts are of different durations and have a different level of risk depending on how much time ADS-B is unavailable as the surveillance system. Altitude deviation refers to the deviation between barometric and geometric altitude. Deviation ranges from 25 feet to 600 feet have been observed. As of now, barometric altitude has been used for separation and surveillance while geometric altitude can be used in cases where barometric altitude is not available. Many UAS might not have both sensors installed on board due to size and weight constrains. There might be a chance of misinterpretation of vertical separation specially while flying in National Airspace (NAS) if the ownship UAS and intruder manned aircraft use two different altitude sources for separation standard. The characteristics and agreement between two different altitudes is investigated with a regression based approach. Multiple risk matrices are established based on the severity of the DAA well clear. ADS-B is called the Backbone of FAA Next Generation Air Transportation System, NextGen. NextGen is the series of inter-linked programs, systems, and policies that implement advanced technologies and capabilities. ADS-B utilizes the Satellite based Global Positioning System (GPS) technology to provide the pilot and the Air Traffic Control (ATC) with more information which enables an efficient navigation of aircraft in increasingly congested airspace. FAA mandated all aircraft, both manned and unmanned, be equipped with ADS-B out by the year 2020 to fly within most controlled airspace. As a fundamental component of NextGen it is crucial to understand the behavior and potential risk with ADS-B Systems

Space Governance for the 21st Century: Balancing Space Development with Sustainability

The development of space is occurring in new ways and at an accelerated pace compared to even just a decade ago. As new and greater volumes of space activities, like large constellations of small satellites, space traffic management, and on orbit rendezvous, proximity, servicing, and assembly operations become routine, new international governance will be necessary to balance the development of space with space sustainability. While some international space governance does exist, it is poorly suited to govern new space activities and the environmental threats posed by space development. The need for new governance is well documented, yet the international community, and specifically the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS), has been unable to organize around space governance and produce effective international governance measures.This research will compare governance regimes of the air, maritime, and internet domains to understand how stakeholders and international organisations approach governance of a global commons. Through the examination of the International Maritime Organization, International Civil Aviation Organization, and the multistakeholder group responsible for internet governance this research will draw insight into the organisational structures, processes, tools, and techniques that aid in the creation of international governance to inform new governance for space.Findings offer insight into the organisational qualities, governance tools, and necessary change needed to govern space more effectively. First, despite differences across case studies, there are key features of effective international governance present in each. Each system of governance is designed based on unique features and qualities of that domain and its stakeholders. Still, decision-making processes, membership participation, enforcement, and keeping pace with new technology all play central roles in effective international governance.Proper consensus decision-making can play an outsized role in whether a forum can advance governance or not. The case studies make clear that to properly use consensus as a decision-making approach requires thoughtful consideration of the increased transaction costs weighed against necessary agreement compliance. For example, not all governance outputs require a high degree of compliance to be effective and therefore do not justify higher transaction costs associated with strict consensus processes. Similarly, thoughtful use of consensus also requires evaluating where in the diplomatic process consensus is required. Not every diplomatic decision requires full consensus. Yet, COPUOS currently does not adjust its decision-making approach based on output or where in the diplomatic process it requires consensus, which has allowed the forum's use of consensus to hinder the development of new governance.Another finding is that strong governance leverages a multitude of governance tools. Treaties are an important governance measure, but so too are standards and recommended practices, guidelines, codes, performance-based measures, audit schemes, scoping exercises, and educational resources, among other tools. Many of the emerging space activities will continue to evolve quickly, which requires producing governance in a timely manner and continuous evolution of agreements. In each case study, evolving activities were governed by a spectrum of measures that allowed the IO to affect member behaviour quickly and overtime through complementary outputs.Each case study made clear that effective governance requires constant work across multiple workstreams, yet COPUOS is a small three body organisation with too few resources to increase work cadence or volume. A larger secretariat and the capacity to create new subcommittees or working groups is likely to aid space governance. COPUOS will require major changes to accommodate space governance needs. Finally, this research offers recommendations for future research capable of exploring additional possible solutions to existing space governance problems

Assuring safety through operational approval : challenges in assessing and approving the safety of systems-level changes in air transportation

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, February 2010."September 2009." Cataloged from PDF version of thesis.Includes bibliographical references (p. 135-143).To improve capacity and efficiency of the air transportation system, a number of new systems-level changes have been proposed. Key aspects of the proposed changes are combined functionality across technology and procedures and large physical scale of deployment. The objective of this work is to examine the current safety assessment processes for systems-level changes and to develop an understanding of key challenges and implications for the assessment and approval of future systems-level changes. From an investigation of current U.S. and international safety regulatory policies and processes, a general model was created describing key processes supporting operational approval. Within this model, a framework defined as an influence matrix was developed to analyze key decisions regarding the required scope of analysis in safety assessment. The influence matrix represents the expected change in levels of risk due to changes in behavior of elements of a system. It is used to evaluate the appropriate scope of analysis in safety assessment. Three approaches to performing safety assessment of systems-level changes were analyzed using the framework: the risk matrix approach, target level of safety approach, and performance-based approach. Case studies were performed using eight implemented and pending systems-level changes. In this work, challenges expected in safety assessment of future systems-level changes were identified. Challenges include the large scope of proposed changes, which drives a need for a broad and deep scope of analysis, including the multiple hazards and conditions and complex interactions between components of a change and the external system. In addition, it can be expected that high safety expectations will increase the required accuracy of models and underlying data used in safety assessment. Fundamentally new operational concepts are also expected to expand the required scope of safety assessment, and a need to interface with legacy systems will limit achievable operations. The large scope of analysis expected for future changes will require new methods to manage scope of safety assessment, and insights into potential approaches are discussed.by Roland Everett Weibel.Ph.D

Naval Research Program 2021 Annual Report

NPS NRP Annual ReportThe Naval Postgraduate School (NPS) Naval Research Program (NRP) is funded by the Chief of Naval Operations and supports research projects for the Navy and Marine Corps. The NPS NRP serves as a launch-point for new initiatives which posture naval forces to meet current and future operational warfighter challenges. NRP research projects are led by individual research teams that conduct research and through which NPS expertise is developed and maintained. The primary mechanism for obtaining NPS NRP support is through participation at NPS Naval Research Working Group (NRWG) meetings that bring together fleet topic sponsors, NPS faculty members, and students to discuss potential research topics and initiatives.Chief of Naval Operations (CNO)Approved for public release. Distribution is unlimited.