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A passive gas removal device, i.e. gas trap is used in the Internal Thermal Control System (ITCS) of the International Space Station (ISS) to remove non-condensable gases to prevent the cavitation or air locking of the pump and malfunction of the pressure and flow sensors. Since the non-condensable gases are always ingested into the ITCS during the routine maintenance and/or replacement of components in the ITCS, it is necessary to have an efficient and reliable gas trap in the liquid coolant loop of the ITCS. To increase tolerance to particulate and microbial growth fouling, extend the operational life, reduce the cost and on-orbit maintenance, and decrease crew workload, an alternative gas trap composed of only one type of membrane is developed. This paper describes the efforts involved in this development, which include the design concept of the alternative gas trap, performance modeling, and the preliminary performance test of the alternative gas trap in the relevant environment.

This work deals with modeling and analysis of a 3-phase Phase-Locked Loop (PLL) based on an algebraic-summation scheme rather than the Stationary/Floating frame transformation PLL or synchronous (Delta Q) frame transformation PLL, and operated to lock on either linear or nonlinear load current waveform, and in the presence of a loss of phase or unbalanced 3-phase load. The PLL scheme is described and performance results are presented, demonstrating its ability to estimate phase and frequency of the input signal in aerospace applications in which a Unity Vector production and a Frequency-to-Voltage conversion is performed.

Modeling and analysis of a reduced order tracking 3-phase Phase-Locked Loop (PLL) based on a combined control principle (error + disturbance) to improve PLL locking performance is presented in this work. The principle is in synthesizing a feedforward control that is added to a Stationary/Floating Frame Transformation PLL or Synchronous (Delta Q) Frame Transformation PLL. The feedforward comprises a frequency-to-voltage converter based on a phase/frequency estimation using an algebraic summation while implementing an inverse feedforward control principle relative to the part of the feedback loop seen after the summing junction. The reduced order tracking PLL is shown to desensitize the system relative to the conventional part PI controller tuning parameters and is operated to lock on either linear or nonlinear load current waveform and for arbitrary frequency/phase profile while maintaining stability by minimizing system dynamics.

The term Integrated Vehicle Health Management (IVHM) describes a set of capabilities that enable sustainable and safe operation of components and subsystems within aerospace platforms. However, very little guidance exists for the systems engineering aspects of design with IVHM in mind. It is probably because of this that designers have to use knowledge picked up exclusively by experience rather than by established process. This motivated a group of leading IVHM practitioners within the aerospace industry under the aegis of SAE's HM-1 technical committee to author a document that hopes to give working engineers and program managers clear guidance on all the elements of IVHM that they need to consider before designing a system. This proposed recommended practice (ARP6883 [1]) will describe all the steps of requirements generation and management as it applies to IVHM systems, and demonstrate these with a “real-world” example related to designing a landing gear system.

During participation on EU FP7 HAIC project, Honeywell has developed methodology to detect High Altitude Ice Crystals with the Honeywell IntuVue® RDR-4000 X-band Weather Radar. The algorithm utilizes 3D weather buffer of RDR-4000 weather radar and is based on machine learning. The modified RDR-4000 Weather Radar was successfully flight tested during 2016 HAIC Validation Campaign; the technology was granted Technology Readiness Level 6 by HAIC consortium. After the end of HAIC project, the method was also evaluated with respect to newly set preliminary industry standard performance requirements1. This paper discuses technology design rationale, high level technology architecture, technology performance, and challenges associated with performance evaluation.

The purpose of the Los Alamos High-Energy Neutron Testing Handbook is to provide user information and guidelines for testing Integrated Circuits (IC) and electronic systems at the Irradiation of Chips and Electronics (ICE) Houses at the Los Alamos Neutron Science Center (LANSCE) at Los Alamos National Laboratory (LANL). Microelectronic technology is constantly advancing to higher density, faster devices and lower voltages. These factors may increase device susceptibility to radiation effects. The high-energy neutron source at LANSCE/LANL provides the capability for accelerated neutron testing of semiconductor devices and electronic systems and to simulate effects in various neutron environments.