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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2016

UAS Integration in the NAS Project: DAA-TCAS Interoperability "mini" HITL Primary Results

At the May 2015 SC-228 meeting, requirements for TCAS II interoperability became elevated in priority. A TCAS interoperability workgroup was formed to identify and address key issues/questions. The TCAS workgroup came up with an initial list of questions and a plan to address those questions. As part of that plan, NASA proposed to run a mini HITL to address display, alerting and guidance issues. A TCAS Interoperability Workshop was held to determine potential display/alerting/guidance issues that could be explored in future NASA mini HITLS. Consensus on main functionality of DAA guidance when TCAS II RA occurs. Prioritized list of independent variables for experimental design. Set of use cases to stress TCAS Interoperability.

human systems integration↗
NASA NTRS2017

The Generic Resolution Advisor and Conflict Evaluator (GRACE) for Detect-And-Avoid (DAA) Systems

The paper describes the Generic Resolution Advisor and Conflict Evaluator (GRACE), a novel alerting and guidance algorithm that combines flexibility, robustness, and computational efficiency. GRACE is "generic" in that it makes no assumptions regarding temporal or spatial scales, aircraft performance, or its sensor and communication systems. Accordingly, GRACE is well suited to research applications where alerting and guidance is a central feature and requirements are fluid involving a wide range of aviation technologies. GRACE has been used at NASA in a number of real-time and fast-time experiments supporting evolving requirements of DAA research, including parametric studies, NAS-wide simulations, human-in-the-loop experiments, and live flight tests.

Unmanned Aircraft↗
NASA NTRS2018

ADS-B Mixed sUAS and NAS System Capacity Analysis and DAA Performance

Automatic Dependent Surveillance-Broadcast (ADS-B) technology was introduced more than twenty years ago to improve surveillance within the US National Airspace Space (NAS) as well as in many other countries. Via the NextGen initiative, implementation of ADS-B technology across the US is planned in stages between 2012 and 2025. ADS-B's automatic one second epoch packet transmission exploits on-board GPS-derived navigational information to provide position information, as well as other information including vehicle identification, ground speed, vertical rate and track angle. The purpose of this technology is to improve surveillance data accuracy and provide access to better situational awareness to enable operational benefits such as shorter routes, reduced flight time and fuel burn, and reduced traffic delays, and to allow air traffic controllers to manage aircraft with greater safety margins. Other than the limited amount of information bits per packet that can be sent, ADS-B's other hard-limit limitation is capacity. Small unmanned aircraft systems (sUAS) can utilize limited ADS-B transmission power, in general, thus allowing this technology to be considered for use within a combined NAS and sUAS environment, but the potential number and density of sUAS predicted for future deployment calls into question the ability of ADS-B systems to meet the resulting capacity requirement. Hence, studies to understand potential limitations of ADS-B to fulfill capacity requirements in various sUAS scenarios are of great interest. In this paper we, validate/improve on, previous work performed by the MITRE Corporation concerning sUAS power and capacity in a sUAS and General Aviation (GA) mixed environment. In addition, we implement its inherent media access control layer capacity limitations which was not shown in the MITRE paper. Finally, a simple detect and avoid (DAA) algorithm is implemented to display that ADS-B technology is a viable technology for a mixed NAS/sUAS environment even in proposed larger mixed density environments.

Matheou, Konstantin J.↗
NASA NTRS2018

ADS-B Mixed sUAS and NAS System Capacity Analysis and DAA Performance

Automatic Dependent Surveillance-Broadcast (ADS-B) technology was introduced more than twenty years ago to improve surveillance within the US National Airspace Space (NAS) as well as in many other countries. Via the NextGen initiative, implementation of ADS-B technology across the US is planned in stages between 2012 and 2025. ADS-B's automatic one second epoch packet transmission exploits on-board GPS-derived navigational information to provide position information, as well as other information including vehicle identification, ground speed, vertical rate and track angle. The purpose of this technology is to improve surveillance data accuracy and provide access to better situational awareness to enable operational benefits such as shorter routes, reduced flight time and fuel burn, and reduced traffic delays, and to allow air traffic controllers to manage aircraft with greater safety margins. Other than the limited amount of information bits per packet that can be sent, ADS-B's other hard-limit limitation is capacity. Small unmanned aircraft systems (sUAS) can utilize limited ADS-B transmission power, in general, thus allowing this technology to be considered for use within a combined NAS and sUAS environment, but the potential number and density of sUAS predicted for future deployment calls into question the ability of ADS-B systems to meet the resulting capacity requirement. Hence, studies to understand potential limitations of ADS-B to fulfill capacity requirements in various sUAS scenarios are of great interest. In this paper we, validate/improve on, previous work performed by the MITRE Corporation concerning sUAS power and capacity in a sUAS and General Aviation (GA) mixed environment. In addition, we implement its inherent media access control layer capacity limitations which was not shown in the MITRE paper. Finally, a simple detect and avoid (DAA) algorithm is implemented to display that ADS-B technology is a viable technology for a mixed NAS/sUAS environment even in proposed larger mixed density environments.

Matheou, Konstantin↗
NASA NTRSDate not supplied

DANTi, DAA in the Cockpit

DANTi is a prototype Electronic Flight Bag which incorporates an assistive Detect and Avoid (DAA) capability developed by NASA.

Maria Consiglio↗
NASA NTRS1972

DAA realizations of attitude algorithms

The attitude algorithms applied to strapdown inertial platforms are discussed. A review of six attitude transformation algorithms and the realizations of these algorithms by digital differential analyzers are presented. The number of digital differential analyzers for each algorithm is either smaller than or equal to that obtained by others.

Hung, J. C.↗
NASA NTRS1982

Demonstration Advanced Avionics System (DAAS)

The feasibility of developing an integrated avionics system suitable for general aviation was determined. A design of reliable integrated avionics which provides expanded functional capability that significantly enhances the utility and safety of general aviation at a cost commensurate with the general aviation market was developed. The use of a data bus, microprocessors, electronic displays and data entry devices, and improved function capabilities were emphasized. An avionics system capable of evaluating the most critical and promising elements of an integrated system was designed, built and flight tested in a twin engine general aviation aircraft.

Source record↗
NASA NTRS1981

Demonstration Advanced Avionics System (DAAS). Phase 1 report

An integrated avionics system which provides expanded functional capabilities that significantly enhance the utility and safety of general aviation at a cost commensurate with the general aviation market is discussed. Displays and control were designed so that the pilot can use the system after minimum training. Functional and hardware descriptions, operational evaluation and failure modes effects analysis are included.

Source record↗
NASA NTRS2018

Ubiquitous Surveillance Notional Architecture for System-Wide DAA Capabilities in the NAS

There is an increasing demand for access to the national airspace system (NAS) by new entrants such as unmanned aircraft systems (UASs) and space vehicles. The need is driving the research into the development of a ubiquitous surveillance framework. A framework where all means of aircraft position tracking systems, both cooperative and noncooperative, would be correlated and made available to all NAS users. The architecture of an envisioned surveillance system was the focus of a recent Volpe National Transportation Systems Center research activity. In this work, the term ''Framework'' is used to characterize an operational environment that forms the context for future UAS operations. Within this framework, the use of all existing and future surveillance technologies is envisioned. Included would be all airspace locations; including coverage for airspace not under surveillance today. While these surveillance means and methods of air traffic control may currently constrain new entrant operations, they also provide the opportunity for the plethora of enabling technological capabilities with associated policies and procedures that can result in the safe, orderly and efficient operation. The focus of this paper is to survey and identify surveillance technologies to support the integration of new entrants in the NAS, and how those technologies can be aggregated.

Surveillance↗
NASA NTRS2017

NASA Phase 2 DAA HITL Schedule

This schedule discusses which HiTLs will be run and the timeframe for each event. This document also discusses system architecture and data flow. The simulation environments is also briefly addressed in the document including: the ground control station and the supported simulation software.

TCAS Interoperaability↗
NASA NTRS2019

Science Mission Directorate TechPort Records for 2019 STI-DAA Release

The role of the Science Mission Directorate (SMD) is to enable NASA to achieve its science goals in the context of the Nation's science agenda. SMD's strategic decisions regarding future missions and scientific pursuits are guided by Agency goals, input from the science community including the recommendations set forth in the National Research Council (NRC) decadal surveys and a commitment to preserve a balanced program across the major science disciplines. Toward this end, each of the four SMD science divisions -- Heliophysics, Earth Science, Planetary Science, and Astrophysics -- develops fundamental science questions upon which to base future research and mission programs.

Seablom, Michael S.↗
NASA NTRSDate not supplied

RTCA Special Committee 228 Working Group (DAA) 1

The Radio Technical Commission for Aeronautics (RTCA) is an American organization comprised of government, industry, and academic stakeholders in aviation for the purpose of providing technical guidance to regulatory authorities. In late 2022, RTCA Special Committee 228 (Minimum Performance Standards for Unmanned Aircraft Systems) decided to form a working group to study a burgeoning multi-vehicle, supervisory control paradigm colloquially known as "m:N" (vocalized as "em-to-en"). Within the m:N control paradigm, multiple aircraft (N) are collaboratively managed by a body of operators/pilots (m). This presentation describes the scope of the m:N working group and its goal of producing an Operational Service and Environment Definition (OSED) for m:N operations.

RTCA↗
NASA NTRS2016

Evaluating Alerting and Guidance Performance of a UAS Detect-And-Avoid System

A key challenge to the routine, safe operation of unmanned aircraft systems (UAS) is the development of detect-and-avoid (DAA) systems to aid the UAS pilot in remaining "well clear" of nearby aircraft. The goal of this study is to investigate the effect of alerting criteria and pilot response delay on the safety and performance of UAS DAA systems in the context of routine civil UAS operations in the National Airspace System (NAS). A NAS-wide fast-time simulation study was conducted to assess UAS DAA system performance with a large number of encounters and a broad set of DAA alerting and guidance system parameters. Three attributes of the DAA system were controlled as independent variables in the study to conduct trade-off analyses: UAS trajectory prediction method (dead-reckoning vs. intent-based), alerting time threshold (related to predicted time to LoWC), and alerting distance threshold (related to predicted Horizontal Miss Distance, or HMD). A set of metrics, such as the percentage of true positive, false positive, and missed alerts, based on signal detection theory and analysis methods utilizing the Receiver Operating Characteristic (ROC) curves were proposed to evaluate the safety and performance of DAA alerting and guidance systems and aid development of DAA system performance standards. The effect of pilot response delay on the performance of DAA systems was evaluated using a DAA alerting and guidance model and a pilot model developed to support this study. A total of 18 fast-time simulations were conducted with nine different DAA alerting threshold settings and two different trajectory prediction methods, using recorded radar traffic from current Visual Flight Rules (VFR) operations, and supplemented with DAA-equipped UAS traffic based on mission profiles modeling future UAS operations. Results indicate DAA alerting distance threshold has a greater effect on DAA system performance than DAA alerting time threshold or ownship trajectory prediction method. Further analysis on the alert lead time (time in advance of predicted loss of well clear at which a DAA alert is first issued) indicated a strong positive correlation between alert lead time and DAA system performance (i.e. the ability of the UAS pilot to maneuver the unmanned aircraft to remain well clear). While bigger distance thresholds had beneficial effects on alert lead time and missed alert rate, it also generated a higher rate of false alerts. In the design and development of DAA alerting and guidance systems, therefore, the positive and negative effects of false alerts and missed alerts should be carefully considered to achieve acceptable alerting system performance by balancing false and missed alerts. The results and methodology presented in this study are expected to help stakeholders, policymakers and standards committees define the appropriate setting of DAA system parameter thresholds for UAS that ensure safety while minimizing operational impacts to the NAS and equipage requirements for its users before DAA operational performance standards can be finalized.

UAS Detect-and-Avoid (DAA) System↗
NASA NTRS2018

An Exploratory Evaluation of UAS Detect and Avoid Operations in the Terminal Environment

New technical standards for Unmanned Aircraft Systems (UAS) detect and avoid (DAA) systems mark recent progress toward realizing the goal of full integration of UAS into the National Airspace System (NAS). The DAA system is intended to provide a means of compliance with operating regulations that required pilots on board manned aircraft to remain "well clear" of other aircraft which is accomplished through out-the-window visual acquisition of other aircraft and application of a subjective judgment of safe separation. The requirements for the DAA system, including the specification of a DAA well clear threshold as well as functional requirements for detecting, tracking, alerting and guidance processing, and displays, are specified in DO-365, Minimum Operational Performance Standards (MOPS) for DAA Systems developed within RTCA (Radio Technical Commission for Aeronautics) Special Committee 228 (SC-228). Intended as the first in a series of phased versions, these requirements are frequently referred to as the "Phase 1" DAA system. The Phase 1 DAA system is limited for use by aircraft transitioning to and from Class A or special use airspace, through Class D, E, and G airspace. In particular, the Phase 1 DAA MOPS are not intended for terminal airspace operations, a critical gap for enabling a full range of UAS operations. The application of the Phase 1 DAA system and DAA well clear threshold within the terminal area is predicted to result in a high number of unnecessary alerts when the UAS is safely separated from other traffic. The goal of the present study was to examine pilot performance and operational issues related to the operation of the Phase 1 DAA system in a terminal area. This experiment was intended as an exploratory study that would be used to inform the development of a new terminal area-specific DAA well clear definition, and associated alerting and guidance requirements. The two main objectives of this study were to: 1) characterize pilot behavior in the terminal environment with the Phase 1 DAA system, and 2) investigate the effect of modifications to the Phase 1 DAA alerting and guidance structure. In particular, the authors were interested in determining whether the removal of specific alerting and guidance levels, without changing the DAA well clear definition or alerting thresholds, would impact pilot performance while conducting terminal operations. The results indicate that the Phase 1 well clear definition and alerting and guidance resulted in frequent alerting that degraded pilots' ability to discriminate between encounters where another aircraft was safely separated versus when a maneuver was necessary. The resulting impact on pilot performance was slower response times and higher frequency and severity of losses of DAA well clear compared to those observed for experiments examining pilot performance in the en route environment. There was no significant effect of alerting and guidance display configuration on pilot performance.

terminal area↗