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The civil Unmanned Aircraft System (UAS) sector is growing rapidly, with a notable orientation towards applications considered too dull, dirty, dangerous or demanding for conventionally piloted aircraft. Operations in this sector present hazards of two main kinds: to other aircraft, and to people and property overflown by UAS. Methods currently used for assessing these hazards and for managing safety...
We consider the development of an imaging system consisting of an array of optical apertures for operation over long atmospheric paths. Typical multi-aperture systems combine the information collected by the apertures in an optical manner. In contrast, image formation in our approach is performed digitally according to the following procedure: (1) the complex-valued amplitude of the received optical...
A new Solar Aspect System (SAS) has been developed to provide the ability to observe the Sun on an existing balloon payload HERO (short for High Energy Replicated Optics). Developed under the HEROES program (High Energy Replicated Optics to Explore the Sun), the SAS aspect system provides solar pointing knowledge in pitch, yaw, and roll. The required precision of these measurements must be better...
Innovation comes in many flavors, from organizational alignment, human resources, processes that support business and product execution, and products that define the enterprise. United Launch Alliance (ULA) origins stem from Lockheed Martin and Boeing when they revolutionized global space access with the introduction of their respective Atlas V and Delta IV rockets in the formulation of the Evolved...
Due to harsh and inaccessible operating environments, space computing presents many unique challenges with respect to stringent power, reliability, and programmability constraints that limit on-board processing performance and mission capabilities. However, the increasing need for real-time sensor and autonomous processing, coupled with limited communication bandwidth with ground stations, are increasing...
The future generation of High Throughput Satellite (HTS) for broadband distributed user access is strictly connected to the use of Ka-band and beyond frequencies. This is related to the requirement of reaching the so-called “terabit connectivity” to support the increasing bit rate requirements.
This paper presents the design of a compact uniform circular antenna array system used in conjunction with the RT-1944/U radio and reports the obtained experimental results. The proposed system was primarily designed to increase the communications range between Littoral Combat Ship (LCS) sea frames and Mission Package Unmanned Surface Vehicles (USVs) by developing a modular aerostat communications...
The Cyclone Global Navigation Satellite System (CYGNSS), which was selected as the Earth Venture-2 investigation by NASA's Earth Science System Pathfinder (ESSP) Program, measures the ocean surface wind field with unprecedented temporal resolution and spatial coverage, under all precipitating conditions, and over the full dynamic range of wind speeds experienced in a tropical cyclone (TC). The CYGNSS...
NASA is currently conducting an architecture study for the next-generation Space Communication and Navigation system. This is an extremely complex problem with a variety of options in terms of band selection (RF, from S-band to Ka-band and beyond, or optical), network type (bent-pipe, circuit-switched, or packet-switched), fractionation strategies (monolithic, mother-daughters, homogeneous fractionation),...
Geodetic imaging data from Interferometric Synthetic Aperture Radar (InSAR) are used to measure crustal deformation related to tectonic motions and displacements on earthquake faults. NASA's UAVSAR project and related efforts are creating large catalogs of data products. The user base of these data products is also growing, introducing the need for downstream tools to support computationally expensive...
This paper summarizes a coordinated set of research efforts to support human and robotic missions to lunar, asteroid, and outer solar system destinations. Research areas include 1) selection and development of biosensors for astronauts engaged in long-duration, strenuous extra-vehicular activities, 2) sensor placement and operation inside spacesuits with minimal impact and maximum configurability...
Heterogeneous Spacecraft Networks (HSNs) are network environments in which spacecraft from different missions and institutions can communicate with each other at low cost and with low impact on overall system resources. The Mission Design Center (MDC) at NASA Ames Research Center has been studying solutions for low cost multi-spacecraft systems for a number of years. One may now build on the idea...
In this paper, a direct connection between the covariance debiasing methodology for the distributed Kalman (DKF) filter in [1] and the federated Kalman filter is shown. In particular, it can be seen that for a unique choice of the information gain hypothesis of the DKF, the covariance debiasing becomes equivalent to the federated Kalman filter. As the complexity of the covariance calculation for the...
We show the feasibility of free-space orbital angular momentum (OAM)-based laser communication through a laboratory experiment in which three OAM channels —each on an independent Laguerre-Gauss (LG) laser mode— are simultaneously transmitted over 11 m on a common optical axis, using single transmit and receive apertures. Each channel is modulated using on-off keying (OOK) at 80 Mb/s and imposed OAM...
The energetic protons trapped in the inner Van Allen belt pose a risk to humans and spacecraft operating in Low Earth Orbit (LEO). These particles come from cosmic rays, solar storms and other processes, and they are a hindrance to development of space technologies. The Radiation Belt Remediation (RBR) idea has been proposed as a way to solve this problem through Ultra/Very Low Frequency (VLF/ULF)...
By virtue of operating at altitudes of 35 km, above 99.5% of the Earth's atmosphere, balloon-borne observatories have several advantages over ground-based and airborne observatories, including space-like image quality, access to the IR spectrum from 1 to 30 microns, very stable photometry and the potential for 100-day missions. We present plans for modifying inexpensive COTS telescopes for use in...
A human-in-the-loop experiment was conducted at the NASA Ames Research Center Vertical Motion Simulator, where instrument-rated pilots completed a simulated terminal descent phase of a lunar landing. Ten pilots participated in a 2 x 2 mixed design experiment, with level of automation as the within-subjects factor and failure frequency as the between-subjects factor. The two evaluated levels of automation...
Scheduling of contacts between space vehicles (SVs) and ground stations is of extreme significance since it is absolutely essential for data receipt from and transmission to satellites, vehicle maintenance, and orbit tracking and maintenance. We looked at the problem of scheduling contacts between SVs and the Air Force's Satellite Control Network (SCN). Our work integrates case-based reasoning, rule...
One of the more challenging aspects of software development is the ability to verify and validate the functional software requirements dictated by the Software Requirements Specification (SRS) and the Software Detail Design (SDD). Insuring the software has achieved the intended requirements is the responsibility of the Software Quality team and the Software Test team. The utilization of Timeliner-TLX™...
This paper introduces a compact optical payload enabling vision-based navigation and hazard detection during terrestrial rocket flights. This payload, the Terrain-Relative Navigation & Descent Imager (TRNDI), serves as an add-on module for Draper Laboratory's GENIE Autonomous-GNC system. GENIE's inertial navigation system relies on GPS during terrestrial test flights, making it insufficient for...
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