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We propose a novel approach to provide authenticity and integrity of Automatic Dependent Surveillance-Broadcast (ADS-B) messages. We employ a key-management schema for authentication and rely on a key-edhashed message authentication code (HMAC) for integrity. Our approach avoids scalability and compatibility issues, as we neither change the packet format nor its size.
Resistive random access memories (RRAM) can be made of a variety of materials, including metal oxides and metal-doped chalcogenides, that exhibit memristive behavior. RRAMs have been identified as a leading candidate to replace flash memory and may also be suitable as replacements for other types of memory, including DRAM and SRAM. When sandwiched between two electrodes, specially grown thin films...
This paper describes a dynamic controller for rotorcraft landing and hovering in ground effect using feedback control based on flowfield estimation. The rotor downwash in ground effect is represented using a potential flow model selected for real-time use. A nonlinear dynamic model of the rotorcraft in ground effect is presented with open-loop analysis and closed-loop control simulation. Flowfield...
This paper describes the design and fabrication of a 26GHz tone generator for the ISARA Cubesat. The tone generator uses a phase locked loop (PLL) frequency multiplier to get to 26GHz from an on board temperature compensated crystal oscillator (TCXO). The output of the PLL feeds a solid state power amplifier (SSPA) that puts out approximately 27dBm of RF power. The SSPA output then feeds a monolithic...
A series of “standard” parts for use in extreme environments based on high-temperature silicon carbide complimentary logic is presented. High temperature results and statistical samples are used to demonstrate the maturity of the parts for extreme environment applications.
SHERLOC is an arm-mounted fluorescence and Raman spectrometer that was recently selected to be part of the payload for the next proposed NASA rover mission to Mars, scheduled for launch in 2020. SHERLOC enables non-contact, spatially resolved, high sensitivity detection and characterization of organics and minerals on the Martian surface. The investigation goals are to assess past aqueous history,...
The Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) is a NASA funded technology-demonstration. SEXTANT will, for the first time, demonstrate real-time, on-board X-ray Pulsar-based Navigation (XNAV), a significant milestone in the quest to establish a GPS-like navigation capability available throughout our Solar System and beyond. This paper describes the basic design of the SEXTANT...
The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) is investigating current and anticipated wireless communications concepts and technologies that the National Airspace System (NAS) may need in the next 50 years. NASA has awarded three NASA Research Announcements (NAR) studies with the objective to determine the most promising candidate technologies for air-to-air...
This paper is to develop a robust guidance and control (G&C) system and corresponding real-time algorithms for ADEPT (Adaptable Deployable Entry Placement Technology) planetary entry vehicle for Mars aerocapture mission with large payloads. The convex optimization based guidance approach is proposed that enables the real-time implementation of the algorithm and increases the predictability and...
The purpose of the Lunar Atmosphere Dust Environment Explorer (LADEE) mission was to measure the density, composition and time variability of the lunar dust environment. The ground-support and onboard flight software for the mission was developed using a “Model-Based Software” methodology. In this technique, models of the spacecraft and flight software are developed in a graphical dynamics modeling...
A model-based method of software system logical design and formal validation will be discussed for the application of fault management throughout the project lifecycle. We have demonstrated that when modeling fault protection system behaviors during the design phases of a project, the expected behavior can be verified early on by executing the model. Correctly capturing the expected behavior in the...
Product Lines are a group of related products manufactured or produced within or between collaborating organizations. To effectively manage a product line, one needs to understand both the similarities and differences between the different products and optimize the development lifecycle to leverage the similarities, and concentrate development on the differences. ISO 26550:2013 Software & Systems...
We discuss the development of a portable NIR reflectance point spectrometer based on acousto-optic tunable filter (AOTF) technology for future in situ geologic investigations of planetary surfaces. AOTFs are low power devices that operate on the principle of diffraction in a birefringent crystal. We have demonstrated the efficacy of this technique in extreme subterranean environments using the Portable...
Current planning and scheduling software tools for International Space Station (ISS) support different flight controller teams as they plan daily space operations. Planning and scheduling tools capabilities include integrating digitized ISS state inputs, evaluating their expected future states, and propagating them over time. Extensive, custom-made computational models of operations, of objectives,...
Current-Pressure (I/P) transducers are effective pressure regulators that can vary the output pressure depending on the supplied electrical current signal, and are commonly used in pneumatic actuators and valves. Faults in current-pressure transducers have a significant impact on the regulation mechanism; therefore, it is important to perform diagnosis to identify such faults and estimate their effect...
This paper considers the problem of tracking a time-varying variable with serially-connected Kalman filters. Two nodes are assumed to be serially connected to the target such that only node 1 can directly observe a noisy signal from the target. Node 2 can only observe noisy signals from node 1 corresponding to a linear combination of the current observation and current state estimate at node 1. The...
This paper presents a 90 nm SiGe BiCMOS comparator designed for extreme environment use. A unique circuit characteristic of this comparator topology is that it uses only one NMOS transistor in the circuit. The rest of the circuit is comprised of PMOS transistors and NPN HBTs in order to maintain radiation hardiness. The circuit was simulated across a temperature range of −195 °C to 155 °C. The circuit...
In this paper, we provide an overview of the current knowledge of radiation effects in anion-based memristive devices. We will specifically look at the impact of high dose rate ionizing radiation, total ionizing dose (TID), and heavy ions on the electrical characteristics of tantalum oxide (TaOx), titanium dioxide (TiO2), and hafnium oxide (HfOx) memristors. The primary emphasis, however, will be...
An asynchronous NULL Convention Logic (NCL) gate library is developed for applications in space environment with temperatures ranging from −196° C to 125° C with radiation exposure. To further improve radiation-immunity and temperature-stability dual high-density metal-insulator-metal (DMIM) capacitor-based delay elements (based on DMIM capacitors available in the IBM 9HP process) and an asynchronous...
The ventilation systems in commercial aircraft cabins are important for providing a healthy and comfortable environment for the passengers and crew. The high density and close proximity of passengers in the modern aircraft cabin exposes them to the risk of contracting airborne diseases such as flu, severe acute respiratory syndrome (SARS), and tuberculosis. Current aircraft personalized ventilation...
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