Patrick Coronado

Bio: Patrick Coronado is an academic researcher from Goddard Space Flight Center. The author has contributed to research in topics: NPOESS & Earth observation. The author has an hindex of 5, co-authored 20 publications receiving 103 citations.

Volume 11, Analysis of Selected Orbit Propagation Models for the SeaWiFS Mission

Abstract: The Sea-viewing Wide Field-of-view Sensor (SeaWiFS)Project is a Code 970.2 activity at the National Aeronau-tics and Space Administration (NASA) Goddard SpaceFlight Center (GSFC). The primary responsibility of theMission Operations element is to provide command sched-ules to maximize performance. Producing these commandschedules requires the propagation of orbit positions overperiods of days to weeks. It is of central importance tothe successful performance of Mission Operations to selectand use an orbit propagation model that will be accurateover these time scales.A secondary responsibility of the Mission Operationselement is to provide pointing vectors and orbit modelsto worldwide ground stations to enable the acquisition ofSeaWiFS data, which are directly broadcast in real time.These direct broadcast data are in High Resolution Pic-ture Transmission (HRPT) format. The time scales forthese activities are typically much less than for commandplanning (usually less than three days).The purpose of this paper is to assess several widelyavailable orbit propagation models for use by Mission Op-erations. Selection of orbit models for use by Mission Op-erations follows three steps: 1) collect requirements forperformance, 2) assess availability of candidate models,and 3) analyze performance in relation to requirements.This analysis was a joint effort by the Mission Operationselement and the SeaWiFS Data Capture Facility (DCF),which is responsible for supporting the HRPT ground sta-tions and has also implemented some of the tested orbitprediction models.

SeaWiFS technical report series. Volume 11: Analysis of selected orbit propagation models for the SeaWiFS mission

Abstract: An analysis of orbit propagation models was performed by the Mission Operations element of the Sea-viewing Wide Field-of-View Sensor (SeaWiFS) Project, which has overall responsibility for the instrument scheduling. The orbit propagators selected for this analysis are widely available general perturbations models. The analysis includes both absolute accuracy determination and comparisons of different versions of the models. The results show that all of the models tested meet accuracy requirements for scheduling and data acquisition purposes. For internal Project use the SGP4 propagator, developed by the North American Air Defense (NORAD) Command, has been selected. This model includes atmospheric drag effects and, therefore, provides better accuracy. For High Resolution Picture Transmission (HRPT) ground stations, which have less stringent accuracy requirements, the publicly available Brouwer-Lyddane models are recommended. The SeaWiFS Project will make available portable source code for a version of this model developed by the Data Capture Facility (DCF).

New technologies to support NASA's Mission to Planet Earth satellite remote sensing product validation: use of an unmanned autopiloted vehicle (UAV) as a platform to conduct remote sensing

Abstract: As part of the US Global Change program, NASA has initiated its Mission to Planet Earth Program (MTPE) which requires continuous global satellite measurements over an extended 15 years period. Various US and International Earth Observing Satellites will be launched during this period. To ensure continuity of the measurements, a significant instrument calibration and product validation effort is required and is planned as part of this program. However, the validation of satellite products requires extensive ground truthing which is both costly and time consuming and in many cases limited to specific calibration/validation areas. Thus there is a need to extend this validation effort to include more participants and provide new, more cost effective technologies to support the validation effort. The use of unmanned autopiloted vehicles (UAV) and new miniature high performance instruments have been identified as providing this needed additional capability. This paper discusses the development of a UAV, associated avionics and preliminary remote sensing instruments to support the extension of ground truthing and product validation of NASA's MTPE Programs, specifically, earth observing system. The UAV being described is based on thrust vectoring capabilities and a single-axis pivoted wing or 'freewing' design. This unique UAV system is illustrated along with the proposed autonomous avionics and preliminary remote sensing payloads.

The AEROS Project - Experiments with Small Electric Powered UAVs for Earth Science [invited]

Abstract: The Airborne Electric Remote Observation Systems (AEROS) project is focused on investigating and refining small UAV concepts for a variety of Earth-science related measurements. Typically aimed at observations on the local scale, recent advances may lead to wide-spread use of small UAVs utilizing electric propulsion and miniaturized sensor systems. Our research has focused on evaluating potential capabilities for both remote sensing and in-situ measurements. Experimentation has included a variety of platforms and instrumentation, and success is bringing new capabilities to the Earth-science community. We envision that these new capabilities will also find utility for environmental, agricultural, commercial, other government, and educational activities. Research objectives, results, and systems are outlined.

Revisiting Spacetrack Report #3

Abstract: Over a quarter century ago, the United States Department of Defense (DoD) released the equations and source code used to predict satellite positions through SpaceTrack Report Number 3 (STR#3). Because the DoD's two-line element sets (TLEs) were the only source of orbital data, widely available through NASA, this code became commonplace among users needing accurate results. However, end users made code changes to correct the implementation of the equations and to handle rare cases encountered in operations. These changes migrated into numerous new versions and compiled programs outside the DoD. Changes made to the original STR#3 code have not been released in a comprehensive form to the public, so the code available to the public no longer matches the code used by DoD to produce the TLEs. Fortunately, independent efforts, technical papers, and source code enabled us to synthesize a non-proprietary version which we believe is up-to-date and accurate. This paper provides source code, test cases, results, and analysis of a version of SGP4 theory designed to be highly compatible with recent DoD versions.

Airborne Communication Networks for Small Unmanned Aircraft Systems

Abstract: This paper explores the role of meshed airborne communication networks in the operational performance of small unmanned aircraft systems. Small unmanned aircraft systems have the potential to create new applications and markets in civil domains, enable many disruptive technologies, and put considerable stress on air traffic control systems. We argue that of the existing networked communication architectures, only meshed ad hoc networking can meet the communication demands for the large number of small aircraft expected to be deployed in future. Experimental results using the heterogeneous unmanned aircraft system are presented to show that meshed airborne communication is feasible, that it extends the operational envelope of small unmanned aircraft at the expense of increased communication variability, and that net-centric operation of multiple cooperating aircraft is possible. Additionally, the ability of airborne networks of small unmanned aircraft to exploit controlled mobility to improve performance is discussed.

SeaWiFS technical report series. Volume 25: Ocean optics protocols for SeaWiFS validation, revision 1

Abstract: This report presents protocols for measuring optical properties, and other environmental variables, to validate the radiometric performance of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), and to develop and validate bio-optical algorithms for use with SeaWiFS data. The protocols are intended to establish foundations for a measurement strategy to verify the challenging SeaWiFS uncertainty goals of 5 percent in water-leaving radiances and 35 percent in chlorophyll alpha concentration. The protocols first specify the variables which must be measured, and briefly review the rationale for measuring each variable. Subsequent chapters cover detailed protocols for instrument performance specifications, characterizing and calibrating instruments, methods of making measurements in the field, and methods of data analysis. These protocols were developed at a workshop sponsored by the SeaWiFS Project Office (SPO) and held at the Naval Postgraduate School in Monterey, California (9-12 April 1991). This report began as the proceedings of the workshop, as interpreted and expanded by the authors and reviewed by workshop participants and other members of the bio-optical research community. The protocols are an evolving prescription to allow the research community to approach the unprecedented measurement uncertainties implied by the SeaWiFS goals; research and development are needed to improve the state-of-the-art in specific areas. These protocols should be periodically revised to reflect technical advances during the SeaWiFS Project cycle. The present edition (Revision 1) incorporates new protocols in several areas, including expanded protocol descriptions for Case-2 waters and other improvements, as contributed by several members of the SeaWiFS Science Team.

Volume 25, Ocean Optics Protocols for SeaWiFS Validation, Revision 1

Abstract: This report presents protocols for measuring optical properties, and other environmental variables, to validate the radiometric performance of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), and to develop and validate bio-optical algorithms for use with SeaWiFS data. The protocols are intended to establish foundations for a measurement strategy to verify the challenging SeaWiFS uncertainty goals of 5% in water-leaving radiances and 35% in chlorophyll a concentration. The protocols first specify the variables which must be measured, and briefly review the rationale for measuring each variable. Subsequent chapters cover detailed protocols for instrument performance specifications, characterizing and calibrating instruments, methods of making measurements in the field, and methods of data analysis. These protocols were developed at a workshop sponsored by the SeaWiFS Project Ofice (SPO) and held at the Naval Postgraduate School in Monterey, California (9–12 April 1991). This report began as the proceedings of the workshop, as interpreted and expanded by the authors and reviewed by workshop participants and other members of the bio-optical research community. The protocols are an evolving prescription to allow the research community to approach the unprecedented measurement uncertainties implied by the SeaWiFS goals; research and development are needed to improve the state-of-the-art in specific areas. These protocols should be periodically revised to reflect technical advances during the SeaWiFS Project cycle. The present edition (Revision 1) incorporates new protocols in several areas, including expanded protocol descriptions for Case-2 waters and other improvements, as contributed by several members of the SeaWiFS Science Team.

A Light-weight Multispectral Sensor for Micro UAV - Opportunities for Very High Resolution Airborne Remote Sensing

Abstract: In this paper we present the prototype of a light-weight multi-spectral sensor which can be flown on a micro UAV and we discuss the promising results from two field tests which show the excellent potential for assessing plant health in agronomical research. We start out by illustrating the gap between airand space-based remote sensing (RS) on the one side and ground-based RS on the other. We highlight the need for (very) high resolution remote sensing offered by low altitude airborne platforms such as mini or micro UAVs (unmanned aerial vehicles). For this purpose, we first discuss the specific characteristics and requirements of typical applications requiring very high resolution RS. We then look into recent developments in light-weight UAV technologies and present the micro UAV which served as platform for the sensor development and tests at the University of Applied Sciences Northwestern Switzerland (FHNW). In the following section we provide a description and discussion of the MultiSpectralMicroSensor (MSMS), the prototype of a light-weight multispectral sensor developed at the FHNW. We further describe two field campaigns with two different types of UAV platforms and MS sensors and discuss the obtained results, which clearly demonstrate the excellent potential of very high-resolution micro UAV based remote sensing applications. * Corresponding author.