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The Van Allen probes team has been successful in monitoring and trending the performance of the mission to date. However, operating two spacecraft in the Van Allen radiation belts poses a number of challenges and requires careful monitoring of spacecraft performance due to the high radiation environment and potential impact on the mostly single string electronics architecture. Spacecraft and instrument...
New trends such as satellite swarms or fractionated spacecraft have experienced a very significant growth in the last decade. Migration from monolithic satellite architectures to new mission architectures involving large constellations of collaborative spacecraft is enabled by several hardware technologies and the application of modularity-driven designs, and presents numerous benefits such as low...
The Synthetic Aperture Radar (SAR) instrument for the proposed NASA/ISRO mission would utilize a distributed architecture dubbed SweepSAR. This real-time On-orbit digital beamforming, combined with lightweight, large aperture reflectors, promises significant increases in instrument capability for solid earth and biomass remote sensing. These new instrument concepts require new methods for calibrating...
We describe a computational technique to assess the near-term Earth impact hazard posed by newly discovered asteroids. In these late warning cases the observational data sets will often include only an hour or so of tracking, leading to a severe degeneracy in the orbit estimation. The systematic ranging approach attacks this problem by exploring the poorly-constrained space of geocentric range and...
This paper summarizes key findings of Asteroid Redirect Mission pre-formulation concept development efforts, including mission architecture and design drivers, flight system concepts and trades, advanced solar electric propulsion component and system options, and asteroid capture option trades and risk reduction efforts. This paper also provides a summary of concept development findings with a focus...
This work focuses on modeling jamming acceptability regions for mission planning scenarios that require support jamming. In such scenarios, electronic attack aircraft are used to obfuscate radar detection of an escorted vehicle, which we call the protected entity (PE), through hostile territory by the use of radar jamming. The calculation of proper jamming acceptability regions (JARs) are needed to...
LARES was developed under the support of the Italian Space Agency. It has been successfully put in orbit on the 13th February 2012 with the VEGA launcher. The main objective of the LARES mission is to test frame-dragging, with the unprecedented accuracy of about 1%. Frame-dragging is that phenomenon, theorized by General Relativity, such that the currents of mass-energy drag spacetime, in the sense...
This paper presents results and conclusions from design, manufacturing, and benchmarking of a heterogeneous computing low power fault tolerant computer, realized on an industrial Qseven® small form factor (SFF) platform. A heterogeneous computer in this context features multi-core processors (CPU), a graphical processing unit (GPU), and a field programmable gate array (FPGA). The x86 compatible CPU...
There are more than two thousands retroreflectors orbiting the Earth. Many are on geodetic satellites typically used for geodesy and geodynamics but also for testing fundamental physics such as in the case of the LARES and LAGEOS satellites. Other are mounted on GPS and GALILEO navigation satellites. Most retroreflectors are Cube Corner Reflectors (CCRs) that rely on the very accurate dihedral angles...
The aim of this paper is to evaluate the benefits of replacing Si Mosfets transistors with enhancement mode GaN transistors in a Half-Bridge Zero Voltage and Zero Current Switching Power Switching Converter (ZVZCPS). This converter is usually used as power supply of the travelling-wave tube amplifiers (TWTAs) in aerospace applications. In this paper, firstly the converter is theoretically analyzed,...
Anomaly detection is an important field for the anticipation of aircraft maintenance operations, working as an enabler of diagnostic and prognostic functions. A method has been implemented to detect abnormal data in Aircraft Condition Monitoring System (ACMS) records. Rather than using already known and usual detection triggers which are partial detectors and insensitive to new flight and system conditions,...
NASA's first Earth Venture mission, the NASA EVM-1 Cyclone Global Navigation Satellite System (CYGNSS), is designed to provide data that will enable the study of the relationship between ocean surface properties, moist atmospheric thermodynamics and convective dynamics. These relationships are postulated to be intrinsic to the genesis and intensification of tropic storms. Key information about the...
This paper describes a method for developing Radiation Hardened by Design (RHBD) multicore processor Integrated Circuits (ICs) that meet specific single-event error rate targets in space environments with minimal impacts on power, area, and speed.
The Asteroid Redirect Mission (ARM) is currently being explored as the next step towards deep space human exploration, with the ultimate goal of reaching Mars. NASA is currently investigating a number of potential human exploration missions, which will progressively increase the distance and duration that humans spend away from Earth. Missions include extended human exploration in cis-lunar space...
We outline the design and test of a new quasi-optical transmission line (QOTL) for feeding the reflector system in an optional instrument for deployment on the Aerosol/Cloud/Ecosystems (ACE) mission. The QOTL used to connect the transmitter and receiver to the antenna is designed for operation at W-band (94 GHz) frequency. A test-bed has been developed for the various critical components of the radar...
A numerical wave optics approach is introduced for simulating beam propagation through anisotropic turbulence. A recently proposed model for anisotropic turbulence is applied and Gaussian beam propagation through the turbulence is implemented for various turbulence strengths and spectral power law α ranging from 3 to 4. Theoretical irradiance expressions are derived and are used to provide comparisons...
This paper presents the design of the Attitude Determination and Control System (ADCS) for the SCOUT imaging spacecraft being developed by Andrews Space. The unique performance constraints of low-cost space vehicles present control and estimation challenges in terms of processor throughput and sensor noise. We discuss the implementation of an ADCS able to achieve sub 100m accuracy (at 450km altitude...
There is an increasing demand for Unmanned Aerial Systems (UAS) to carry suspended loads as this can provide significant benefits to several applications in agriculture, law enforcement and construction. The load impact on the underlying system dynamics should not be neglected as significant feedback forces may be induced on the vehicle during certain flight manoeuvres. The constant variation in operating...
This paper investigates a systematic mission design of robust and optimal orbital transfer maneuvers for a sample return mission from an asteroid. In this study, we establish a space flight procedure to obtain the minimum Delta V required for a rendezvous and sample return mission from an asteroid. Given the initial (observed) conditions of an asteroid, a genetic algorithm is implemented to determine...
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