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Four sealing methods for encapsulating samples in 1 cm diameter thin-walled sample tubes were designed, along with a set of tests for characterization and evaluation of sample preservation capability for the proposed Mars Sample Return (MSR) campaign. The sealing methods include a finned shape memory alloy (SMA) plug, expanding torque plug, contracting SMA ring cap, and expanding SMA ring plug. Mechanical...
Traditional satellite technologies integrate solar panels, thermo mechanical subsystems, power management, data processing and harness subsystems together in a late stage of design. More recently this approach has become inefficient and its limitation can easily be overcome with modern manufacturing technologies. This paper proposes an innovative approach to embed power, signal processing and harness...
Bench development tests of new turbofan engines make an important use of sensor measurements to help engineers understand the behavior of new components design. Such tests are expensive and may be completely compromised if any measurement is missing. One of the big challenges about development tests is to minimize the number of sensors as each measurement has a non-negligible cost. However, if we...
This paper presents a dynamic and robust method to model and calibrate a three axis magnetometer. The STUDSAT-2 (STUDent SATellite-2) satellite uses a low cost three axis digital magneto resistive magnetometer. Low cost magnetometers can be used for estimating the orientation with respect to the magnetic North. Although magnetometers work very well in clean environment, they are strongly influenced...
This paper discusses the dynamics of a tether-based mobile robot in space. The tether-based mobile robot is constrained geometrically using several tethers and can move within an area bounded by the tethers' anchors by changing the tethers' lengths. This robot is equipped with an extendable and retractable arm that approaches the tethers' anchor and reposition it to another point for changing the...
Autonomous health monitoring is a key enabling technology for future space missions. One approach to developing this capability is through model-based fault management. This method seeks to leverage system models in order to enable rapid algorithm development, reduce the burden of verification and validation, and ensure that a large set of possible faults can be detected and identified. Here, a high...
The Deep Space Navigation (DSNav) Architecture Simulation Tool is a MATLAB-based tool box with a GUI front end. It provides a user-friendly interface to the Orbit Determination Toolbox (ODTBX) developed at NASA GSFC as a mission analysis tool. DSNav allows users to visually prototype and simulate navigation scenario cases. The DSNav GUI tool gives users access to new measurement and dynamics models...
From 1992 until 1999, NASA adopted the mission paradigm of Faster-Better-Cheaper (FBC)—i.e., a large number of relatively small, low-cost spacecraft—for its unmanned spacecraft. As many of the early FBC missions met their objectives (at much lower cost than traditional missions), the FBC approach appeared to be viable. However, after two Mars mission failures in 1999, the FBC paradigm was discontinued...
Simple, easy-to-use and physically meaningful analytical predictive models are developed for the evaluation of thermal stresses in bi- and tri-material bodies employed in various aerospace electronic and photonic packaging designs. The numerical examples are carried out for a bi-material assembly comprised of a silicon IC and a ceramic substrate, and for 2) a tri-material body obtained as a result...
We have developed an automatic calibration system for arbitrary shaped array. A signal generator drove a horn antenna to provide a signal source and a spectrum analyzer was connected to the output of an 8 - channel beamformer to collect data. The entire interface was automated using LabVIEW, which included a program to upload the weights to the beamformer, control system for the signal generator,...
The stratospheric airships for telecommunication relay station and ground observations at 20km altitude has been widely used in recent years. Energy recycling system is one of key technologies for the stratospheric airship, which includes solar arrays, storage batteries and power control unit. Both of the battery charge regulator and the battery discharge regulator of power control unit are DC power...
In space communications, standard link analysis assumes that messages are sent once. For a communication link that uses an error-correction coding scheme, bit-error-rate (BER) or frame-error-rate (FER), and link margins are common metrics that characterize the quality of a link, and they are used to determine the supportable data rate. With the advent of Automatic Repeat-reQuest (ARQ) protocols, when...
Cloud computing is evolved from grid computing with a key support from the rapidly expanding virtualization technology. We argue that clouding computing is particularly suitable for supporting emergency response and management (ERM) because of some of its unique features such as rapid setup and deployment on ad hoc basis, highly flexible platforms (PaaS: Platform as a Service) and application services...
Prognostics and Health Management (PHM) [1] is a key enabler of Condition Based Maintenance Plus (CBM+) [2]. In essence, it refers to the “Plus” by providing the ability to predict future health status of a system or component, as well as providing the ability to anticipate faults, problems, potential failures, and required maintenance actions. From the perspective of operation and maintenance (O&M)...
We describe the design and performance of short-wave infrared 3D imaging cameras with focal plane arrays (FPAs) based on Geiger-mode avalanche photodiodes (GmAPDs) with single photon sensitivity for laser radar imaging applications. The FPA pixels incorporate InP/InGaAs(P) GmAPDs for the detection of single photons with high efficiency and low dark count rates. Based on the design of the GmAPD detectors,...
Over the last several years, various research groups have shown that metal oxide-based memristors or resistive random access memory (RRAM) components are tolerant to high levels of both displacement damage and ionizing dose. However, above certain thresholds of either the deposited displacement damage dose or the deposited ionizing dose, devices do respond to radiation. In this paper, the sensitivity...
This paper presents an innovative design solution for a compact Electro-Hydraulic Actuator (EHA). Although the current trend in many mobile applications is towards Electro Mechanical Solutions (EMAS) instead of Hydraulic Actuation systems (HAS), the use of HEAs could represent the best technological compromise. In fact, EHA can combine the power to weight ratio advantage of hydraulic technology with...
When managing technology portfolios like the Small Business Innovative Research (SBIR) Program, NASA makes a considerable effort to gauge the risk and cost as guidance factors for balancing a program. Metrics like the Technology Readiness Level (TRL) are used to determine the maturity of a given technology and thereby provide an assessment of the required steps and funding needed to infuse the technology...
This paper shows the results of two different methods of implementing the semi-greedy auction algorithm for hypothesis selection in the multiple hypothesis radar data association problem. The goal is to compare the Semi-Greedy Track Selection (SGTS) technique proposed by Waard, Capponi et. al. to a traditional semi-greedy approach [2], [3], [4], [5], [6], [12]. This study uses detection data generated...
The US Army's Heavy Brigade Combat Team (HBCT) is investigating the implementation of Vehicle Health Management Systems across its fleet of platforms. A vehicle degrader analysis was conducted to determine where the application of vehicle health management systems (VHMS) could potentially have the greatest impact on increasing maintainer effectiveness and operational availability. The analysis was...
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