Browse Topic: Relays

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Experimental Exploration of Battery-Engine Hybrid-Electric Power SharingF-0081-2025-03615/20/2025
A regulated hybrid-electric power sharing architecture was developed and tested for VTOL applications. In this architecture, there are two power supply branches and one load. The first branch draws power from an engine-generator, and it has additional components of an AC-DC rectifier, a DC-DC buck converter, and a power diode. The second branch draws power from a battery, and it has additional components of a solid-state relay, a DC-DC boost converter, and a power diode. Any specified ratio of battery-to-engine power can be achieved with this architecture. Testing on the full range of power share ratios was conducted at a low load power of 300W. The key conclusions are that: (1) regulated power sharing is feasible between an AC supply and a DC battery, including the extremes of all engine and no battery to all battery and no engine, (2) a specified power share ratio can be achieved both in steady-state and transient conditions, and (3) there is a delay in achieving a specified power share ratio, caused not by the power plant, but rather by the change in RPM of the rotor.
Schmidt, John, Xu, Huan, Datta, Anubhav
CONTACTS, ELECTRICAL CONNECTOR, SOCKET, CRIMP REMOVABLE (FOR MIL-DTL-12883/44, MIL-DTL-12883/45, MIL-DTL-12883/46, AND MIL-DTL-12883/52 RELAY)AS39029/101B (Historical)12/5/2019
AE-8C1 Connectors Committee
Guarding of Starter System EnergizationJ1493_201908 (Current)8/8/2019
This SAE Standard describes guarding to help prevent hazardous machine movement caused by activation of the starter motor by bypassing the starter control system. This document is applicable to off-road, self-propelled work machines, as identified in SAE J1116, and agricultural tractors, as defined in ANSI/ASAE S390, which have the potential for hazardous machine movement as a result of bypassing the starter control system and powering of the starter motor.
OPTC1, Personnel Protection (General)
Standardized Symbols for Electrical Circuit DiagramsJ2221_201905 (Current)5/16/2019
This SAE Recommended Practice identifies graphic symbols used in electrical circuit diagrams. The symbols aid troubleshooting electrical systems.
Truck and Bus Electrical Systems Committee
Understanding the “Black Art” of RF and Microwave SwitchingTBMG-341264/1/2019
Understanding RF, especially microwave switching, can be a challenge. In many cases, test systems have been compromised because a test engineer did not consider all the components of their test system: instruments, switching, cabling, Mass Interconnect (test fixture interface), fixture design, and so on. Each component has its own set of characteristics. With RF and microwave components, effects including insertion loss, VSWR, bandwidth, and so on all need to be considered as well.
Understanding the “Black Art” of RF and Microwave Switching19AERP04_064/1/2019
Understanding RF, especially microwave switching, can be a challenge. In many cases, test systems have been compromised because a test engineer did not consider all the components of their test system: instruments, switching, cabling, Mass Interconnect (test fixture interface), fixture design, and so on. Each component has its own set of characteristics. With RF and microwave components, effects including insertion loss, VSWR, bandwidth, and so on all need to be considered as well. Higher bandwidth is a constant demand. The most obvious current example is the emergence of 5G systems that will be hitting the market in the near future, but there are many defense systems - often with their own protocols - that are now operating at RF and high-frequency bandwidths. In short, the need to employ repeatable, accurate RF and microwave switching systems is only going to increase, and while this may appear to be a “sexy” subject, without a proper appreciation of the challenges involved, test systems designers could find themselves facing a lengthy process involving a great many iterations while inconsistencies and failures are ironed out.
Generalized Query Tool for Accessing the Database of the Mars Relay Operations Service (MaROS)TBMG-263642/1/2017
The Generalized Query Tool for accessing the database of MaROS can be utilized in three modes: (1) batch mode where a user's authentication data is inserted directly along with a desired query to the database, (2) interactive mode where a desired query is known and can be entered directly, and (3) interactive mode with a query “wizard” that walks a user through the steps needed to construct a valid query to the database. In all three cases, the successful execution of the script results in data from the MaROS database being made available to the user in a comma-separated output file. For new users, it is recommended to use the third mode to build a sample query and then tailor that as desired for use with the first or second modes.
A First Strategy for Smoothing Transients in Switching Controls of Aerospace and Automotive Systems2016-36-040210/25/2016
Switching controls are those that can switch between control or plant modes to perform their functions. They have the advantage of being simpler to design than an equivalent control system with a single mode. However, the transients between those modes can introduce steps or overshootings in the state variables, and this can degrade the performance or even damage the control or the plant. So, the smoothing of such transients is vital for their reliability and mantainability. This is can be of extreme importance in the aerospace and automotive fields, plenty of switchings between manual and autopilot modes via relays, or among gears via clutches, for example. In this work, we present a first strategy for smoothing transients in switching controls of aerospace and automotive systems. To do that, we review the literature, present and adopt a criterion to determine the coefficients of a control system which should optimize the trajectory of the control signal during the switching between two modes. The chosen criteria are the classical integral of the time times the square of the error (ITSE), and the integral of the time times the module of the error (ITME). Effectively, each transition will be done by a subsystem specific for it, according to the selected criterion. The system will be chosen from relevant cases of the literature. The simulations will be made in MATRIXx@ or MATLAB@. The results obtained so far suggest that the proposed strategy effectively reduces the steps or overshootings in the transients between those switching modes and can contribute for the reliability and mantainability of aerospace and automotive systems.
Amaral, Jairo Cavalcanti, de Oliveira e Souza, Marcelo Lopes
SCaN Optical Link Assessment Tool Version 2TBMG-241263/1/2016
In response to the requirements of the Space-Based Relay Study (SBRS) undertaken by NASA in 2013, as well as the Integrated Radio and Optical Communications (iROC) project being conducted by NASA Glenn Research Center (GRC) beginning in 2012, a calculation procedure was required to rapidly assess the operation of optical communication links originating from within deep space (in particular, from around Mars in the case of iROC), as well as within the near-Earth scenarios of LEO and GEO (in the case of SBRS). Such an assessment included the specification of the design components of the optical system to achieve reliable communications as prescribed by one or several metrics that indicate overall system operation. Additionally, it was also desired to be able to dynamically evaluate such optical link operation as the satellite/earth orbital positions evolve during the mission lifetime.
SCaN Optical Link Budget ToolTBMG-2347912/1/2015
In response to the requirements of the Space-Based Relay Study (SBRS) undertaken by NASA in 2013, as well as the Integrated Radio and Optical Communications (iROC) project being conducted by NASA Glenn Research Center (GRC) beginning in 2012, a calculation procedure was required to rapidly assess the operation of optical communication links originating from within deep space (in particular, from around Mars in the case of iROC), as well as within the near-Earth scenarios of LEO (low-Earth orbit) and GEO (geostationary Earth orbit) in the case of SBRS. Such an assessment included the specification of the design components of the optical system to achieve reliable communications as prescribed by one or several metrics that indicate overall system operation.
Mars Relay CubeSatTBMG-228739/1/2015
When NASA and other agencies send landers to Mars and other planets, they rely on existing orbiters to relay the data during the critical entry, descent, and landing (EDL) phase. The current orbiters are aging and there are no current NASA plans to replace them. Future landers have a critical challenge to communicate during a very risky mission phase. The InSight mission will land on Mars in September 2016 with no direct-to-Earth radio link. Instead, Insight expects the Mars Reconnaissance Orbiter (MRO) to be fully functional and placed in an orbit to be in view of the EDL time and place. MRO will take many hours to play back the data to Earth, leaving the project staff without knowledge if their valuable spacecraft has made it safely.
Capacitive Load Switching: Extending Relay Switching Life and Reliability in Military and Aerospace Power Systems2014-01-22089/16/2014
This paper will illustrate how the increasing electrical power demands of military and aerospace applications can continue to successfully be met by high performance electromechanical relays. To meet these higher demands engineering compatibility must be properly understood between the intended application demands and relay switching performance parameters. With high performance electromechanical relays continuing to play a critical part in military and aerospace applications it is more important than ever that engineers capture all of the electrical power switching requirements. A critical area within powering military and aerospace systems is relay life when capacitive load switching. Capacitive loads generate high current levels that are transient in duration and often adversely affect the relay lifespan at the component level and the military or aerospace application reliability at the systems level. Often these transients, while brief in nature, can dramatically exceed the steady-state switching ratings for the contacts in a high performance electromechanical relay. In this paper practical examples of inrush current reduction of capacitive transient high current loads and corresponding increase of relay contact life rating will be reviewed and explored in detail. By adapting the relay circuit design with current inrush reduction components and techniques the user can ensure a properly rated relay will meet the capacitive load switching requirements of the end application. When capacitive loads are properly identified and contained within the relay capabilities a higher degree of application-relay compatibility can be achieved. There are many positive payoffs including increased switching lifespan, functionality, and reliability that enhance the customer experiences under demanding military and aerospace conditions.
Baldwin, Michael
Standardized Symbols for Electrical Circuit DiagramsJ2221_201408 (Historical)8/19/2014
This SAE Recommended Practice identifies graphic symbols used in electrical circuit diagrams. The symbols aid troubleshooting electrical systems.
Truck and Bus Electrical Systems Committee
Guarding of Starter System EnergizationJ1493_201309 (Historical)9/30/2013
This SAE Standard describes guarding to help prevent hazardous machine movement caused by activation of the starter motor by bypassing the starter control system. This document is applicable to off-road, self-propelled work machines, as identified in SAE J1116 and Agricultural Tractors as defined in ANSI/ASAE S390 which have the potential for hazardous machine movement as a result of bypassing the starter control system and powering of the starter motor.
OPTC1, Personnel Protection (General)
Advanced Strategic and Tactical Relay Request Management for the Mars Relay Operations ServiceTBMG-172279/1/2013
This software provides a new set of capabilities for the Mars Relay Operations Service (MaROS) in support of Strategic and Tactical relay, including a highly interactive relay request Web user interface, mission control over relay planning time periods, and mission management of allowed strategic vs. tactical request param eters. Together, these new capabilities expand the scope of the system to include all elements critical for Tactical relay operations.
Real-Time Multimission Event Notification System for Mars RelayTBMG-172649/1/2013
As the Mars Relay Network is in constant flux (missions and teams going through their daily workflow), it is imperative that users are aware of such state changes. For example, a change by an orbiter team can affect operations on a lander team. This software provides an ambient view of the real-time status of the Mars network.
Bilayer Protograph Codes for Half-Duplex Relay ChannelsTBMG-169818/1/2013
Direct to Earth return links are limited by the size and power of lander devices. A standard alternative is provided by a two-hops return link: a proximity link (from lander to orbiter relay) and a deep-space link (from orbiter relay to Earth). Although direct to Earth return links are limited by the size and power of lander devices, using an additional link and a proposed coding for relay channels, one can obtain a more reliable signal. Although significant progress has been made in the relay coding problem, existing codes must be painstakingly optimized to match to a single set of channel conditions, many of them do not offer easy encoding, and most of them do not have structured design.
CONTACTS, ELECTRICAL CONNECTOR, SOCKET, CRIMP REMOVABLE (FOR MIL-DTL-12883/44, MIL-DTL-12883/45, MIL-DTL-12883/46, AND MIL-DTL-12883/52 RELAY)AS39029/101A (Historical)4/20/2013
AE-8C1 Connectors Committee
Aluminum Introduction in Electrical Distribution Systems2013-01-03974/8/2013
For well known reasons, aluminum is challenging copper in automotive EDS. Shortage of resources, material price pressure, gas emission and weight reductions are strong intensives for a break-through. How to support the change, opportunistic solutions or more systematic roll out? Let see Pros and Cons and solutions examples.
Chretien, Louis
Development of a Smart Main Relay Assembly using IGBTs for xEV Battery System2013-01-17644/8/2013
This paper proposes a smart main relay assembly or power relay assembly for xEV battery system. The role of main relay assembly is to connect and disconnect main high voltage battery and loads including the inverter. Current main relay is usually a special electro-mechanical relay which has a gas chamber to suppress electrical sparks between relay contacts for switching high current safely. The gas-chambered electro-mechanical relay is relatively too heavy and bulky to decrease design flexibility and may worsen fuel economy. The proposed smart main relay assembly uses IGBT (insulated gate bipolar transistor) for transient states to switches on or off, and uses relays for steady states to connect or disconnect current. As no spark induces to relay contacts directly with the proposed method, conventional electro-mechanical relays without gas-chambers can be used. Therefore the mass and volume can be reduced to increase gas mileage and also reduce the material cost. Using a current sensor in the assembly, a fail-safe diagnosis function which detects and disconnects an abrupt change of high current up to a given limit, also can be implemented. The prototype of the proposed smart main relay assembly was developed for 80A current load and tested for control and diagnostic functions. The prototype was installed to a hybrid EV and tested including driving conditions. The prototype's fail-safe diagnostic function disconnected high current successfully under the test conditions which include short-circuit to make the previous main relay assembly out of order permanently.
Lee, Taeyeon, Jung, Byungsub, Lee, Sang-Ryong, Kim, Ho-Kyung, Wie, Sa-Heun, Kwon, Dae-Hwan, Joo, Min-Chul
Smart Rear Defog2013-01-15104/8/2013
Smart Rear Defog can be defined as an optimized control algorithm that sets the state of a vehicle's rear defog relay based on a logical assessment of vehicle parameters and environmental conditions. The use of the optimized control algorithm will minimize the amount of user interaction needed to operate the rear defogger and it will minimize the amount of heat rejected to the environment which in turn will improve the vehicle's real world fuel economy or electric range. This paper provides a detailed description of the smart rear defog control system as well as evidence to demonstrate its robustness to variances in environmental conditions and vehicle usage compared to the traditional rear defog system commonly used in many vehicles today.
Delorme, Gilles
Relay Forward-Link File Management Services (MaROS Phase 2)TBMG-159013/1/2013
This software provides the servicelevel functionality to manage the delivery of files from a lander mission repository to an orbiter mission repository for eventual spacelink relay by the orbiter asset on a specific communications pass. It provides further functions to deliver and track a set of missiondefined messages detailing lander authorization instructions and orbiter data delivery state. All of the information concerning these transactions is persisted in a database providing a high level of accountability of the forwardlink relay process.
Mars Relay Lander and Orbiter Overflight Profile EstimationTBMG-1525912/1/2012
This software allows science and mission operations to view graphs of geometric overflights of satellites and landers within the Mars (or other planetary) networks. It improves on the MaROS Web interface within any modern Web browser, in that it adds new capabilities to the MaROS suite.
Relays Enable Curiosity Rover’s Chemistry InstrumentTBMG-1517111/1/2012
NASA’s Curiosity rover landed in the Gale Crater on Mars on August 5, having flown over 127 million miles since its November 2011 launch. As part of NASA’s Mars Exploration Program, Curiosity will look for evidence of past or present habitable environments.
Mars Express Forward Link Capabilities for the Mars Relay Operations Service (MaROS)TBMG-146889/1/2012
This software provides a new capability for landed Mars assets to perform forward link relay through the Mars Express (MEX) European Union orbital spacecraft. It solves the problem of standardizing the relay interface between lander missions and MEX.
MaROS: Information Management ServiceTBMG-109469/1/2011
This software is provided by the Mars Relay Operations Service (MaROS) task to a variety of Mars projects for the purpose of coordinating communications sessions between landed spacecraft assets and orbiting spacecraft assets at Mars. The Information Management Service centralizes a set of functions previously distributed across multiple spacecraft operations teams, and as such, greatly improves visibility into the end-to-end strategic coordination process. Most of the process revolves around the scheduling of communications sessions between the spacecraft during periods of time when a landed asset on Mars is geometrically visible by an orbiting spacecraft. These “relay” sessions are used to transfer data both to and from the landed asset via the orbiting asset on behalf of Earth-based spacecraft operators.
Epiretinal Prosthesis Surgically Implanted in the EyeTBMG-102376/1/2011
In a healthy eye, the photoreceptors (rods and cones) on the retina convert light into tiny electrochemical impulses that are sent through the optic nerve and into the brain, where they are decoded into images. If the photoreceptors no longer function correctly — due to conditions such as retinitis pigmentosa — the first step in this process is disrupted, and the visual system cannot transform light into images.
MaROS: Web Visualization of Mars Orbiting and Landed AssetsTBMG-98735/1/2011
Mars Relay operations currently involve several e-mails and phone calls between lander and orbiter teams in order to settle on an agreed time for performing a communication pass between the landed asset (i.e. rover or lander) and orbiter, then back to Earth. This new application aims to reduce this complexity by presenting a visualization of the overpass time ranges and elevation angle, as well as other information. The user is able to select a specific overflight opportunity to receive further information about that particular pass.
Wireless Orbiter Hang-Angle Inclinometer SystemTBMG-96124/1/2011
A document describes a system to reliably gather the hang-angle inclination of the orbiter. The system comprises a wireless handheld master station (which contains the main station software) and a wireless remote station (which contains the inclinometer sensors, the RF transceivers, and the remote station software). The remote station is designed to provide redundancy to the system. It includes two RF transceivers, two power-management boards, and four inclinometer sensors.
CFDP for Interplanetary Overlay NetworkTBMG-94283/1/2011
The CCSDS (Consultative Committee for Space Data Systems) File Delivery Protocol for Interplanetary Overlay Network (CFDP-ION) is an implementation of CFDP that uses ION’s DTN (delay tolerant networking) implementation as its UT (unit-data transfer) layer. Because the DTN protocols effect automatic, reliable transmission via multiple relays, CFDP-ION need only satisfy the requirements for Class 1 (“unacknowledged”) CFDP. This keeps the implementation small, but without loss of capability.
CONTACTS, ELECTRICAL CONNECTOR, SOCKET, REMOVABLE (FOR MIL-PRF-6106 AND MIL-DTL-12883/40 AND /41 RELAY SOCKETS)AS39029/92A (Historical)12/7/2010
AE-8C1 Connectors Committee
Practical Hybrid Contactors2010-01-175111/2/2010
This paper presents a design for a low loss long life high current contactor consisting of a mechanical contactor teamed with an electronic circuit that eliminates switching stress on the mechanical contacts. A design for a practical 115V 3 phase double throw current protected Hybrid Contactor is presented, along with laboratory and field test data. The idea for a hybrid contactor is not a new one, having been applied since electronic devices became readily available in the 1960s. The key concept is to parallel the mechanical contacts with electronic devices (thyristors or FETs) to handle the current during mechanical contact transition. The mechanical contactor is specially designed to provide low conduction losses without needing to withstand arcing events. The contactor also includes bus control and over-current protection features.
Potter, Fred
Enabling IP Header Compression in COTS Routers via Frame Relay on a Simplex LinkTBMG-862010/1/2010
NASA is moving toward a network-centric communications architecture and, in particular, is building toward use of Internet Protocol (IP) in space. The use of IP is motivated by its ubiquitous application in many communications networks and in available commercial off-the-shelf (COTS) technology. The Constellation Program intends to fit two or more voice (over IP) channels on both the forward link to, and the return link from, the Orion Crew Exploration Vehicle (CEV) during all mission phases. Efficient bandwidth utilization of the links is key for voice applications.
AutoGen Version 5.0TBMG-76023/1/2010
Version 5.0 of the AutoGen software has been released. Previous versions, variously denoted “Autogen” and “autogen,” were reported in two articles: “Automated Sequence Generation Process and Software” (NPO-30746), Software Tech Briefs (Special Supplement to NASA Tech Briefs), September 2007, page 30, and “Autogen Version 2.0” (NPO-41501), NASA Tech Briefs, Vol. 31, No. 10 (October 2007), page 58.
All Motors are Stepping MotorsTBMG-93702/1/2010
In 1938, General Electric began producing a two-phase synchronous induction motor which, at 60 Hz, ran at 75 RPM. The low speed resulted from using a different number of rotors to stator poles or teeth, which made the motor a good bi-directional control motor. This motor was used by Superior Electric Company of Bristol, CT, to run power driven autotransformers used to dim lights in auditoriums and similar applications. General Electric ceased producing this motor in the mid 1950’s due to slow sales.
Siemens Processor Helps KUKA Boost Robot ProductivityTBMG-949012/1/2009
KUKA Flexible Production Systems is a leading producer of production systems for car bodies and chassis. When KUKA decided to become a Tier I supplier of automobile bodies to Chrysler, they needed to use their extensive knowledge of body shops and find a partner willing to work with them to change the landscape of the North American market.
Wireless Network Cocast: Location-Aware Cooperative Communications with Linear Network CodingTBMG-632012/1/2009
In wireless networks, reducing aggregate transmit power and having even power distribution increase the network lifetime. The conventional direct transmission (DTX) scheme results in high aggregate transmit power and uneven power distribution. In conventional DTX, where mobile units directly transmit their information to a common destination, the distant mobile units require more transmit power to provide a comparable quality of service (QoS) to that of the closer ones. Consequently, high aggregate transmit power (the sum of all transmit power of individual mobile units) and uneven power distribution among the units exist in the network. These two issues result in low network lifetime, which is defined as the time until the first mobile unit dies. It is wellknown that diversity techniques such as time diversity, frequency diversity, and spatial diversity result in reduction of transmit power and thus can be used to improve network lifetime. Three location- aware cooperation-based schemes considered in this work are immediateneighbor cooperation (INC), maximal cooperation (MAX), and wireless network cocast (WNC) that achieve spatial diversity to reduce aggregate transmit power and even power distribution. Cooperative communication makes use of the broadcast nature of wireless transmission. Nodes in a network acting as relays can retransmit overheard information to a destination, where the intended information from the source signal and the relay signals is jointly detected. The distributed antennas among the relays are used to provide spatial diversity without the need to use multiple antennas at the source. Various cooperative diversity protocols have been proposed and analyzed. In decodeand- forward (DAF) protocol, each relay decodes the overheard information from the source, re-encodes it, and then forwards it to the destination. In amplify- and-forward (AAF) protocol, each relay simply amplifies the overheard signal and forwards it to the destination.
Cooperative Single-Antenna Node NetworksTBMG-582110/1/2009
Future tactical networks will be complex, with severe constraints on energy and bandwidth, operating in dynamic and unpredictable environments. By exploiting the broadcast nature of the wireless medium and spatially dispersed nodes, some of these advantages can be realized through cooperation among single-antenna nodes in a network.
Relay Sequence Generation SoftwareTBMG-56929/1/2009
Due to thermal and electromagnetic interactivity between the UHF (ultra-high frequency) radio onboard the Mars Reconnaissance Orbiter (MRO), which performs relay sessions with the Martian landers, and the remainder of the MRO payloads, it is required to integrate and de-conflict relay sessions with the MRO science plan. The MRO relay SASF/PTF (spacecraft activity sequence file/ payload target file) generation software facilitates this process by generating a PTF that is needed to integrate the periods of time during which MRO supports relay activities with the rest of the MRO science plans. The software also generates the needed command products that initiate the relay sessions, some features of which are provided by the lander team, some are managed by MRO internally, and some being derived.
Detector Module for Testing Silicon Carbide Semiconductor DevicesTBMG-55518/1/2009
Long-term stress testing of silicon carbide (SiC) semiconductor devices is required to determine suitability for power electronics applications. During testing, preventable catastrophic failures can occur due to drift in steady-state operation or transients that shift the device outside of its safe operating range. Both steady-state and transient drift are easily monitored values including temperature, on-state resistance, voltage, and current, as well as others. By measuring and reacting to shifts in these values, device damage can be minimized.
Wireless Devices for Temperature MonitoringTBMG-50464/1/2009
The growth of wireless instrumentation technology has provided new ways to apply temperature measurement sensors, combined with personal computers, to collect, tabulate, and analyze data. For complex, multi-sensor applications, wireless devices provide a means to eliminate the nuisance of running multiple leads over long distances through harnesses or conduit to a control room, instrument panel, or equipment rack, while keeping track of leads. For simpler one- or two-sensor applications, it means installing the wireless sensor and setting up the receiver.
Safely Stopping Motion Using Discrete WiringTBMG-96802/1/2009
Functional machine safety using discrete wiring is an established way to protect workers from injury, and protect companies from the expense associated with accidents and downtime.
Deciphering the New SUMIT™ SpecificationTBMG-62181/1/2009
The new SUMIT specification is managed by the Small Form Factor Special Interest Group (SFF-SIG). SFF-SIG is a newly formed, non-profit industry group that develops, promotes, and supports small form factor circuit board specifications and related technologies. The group embraces the latest technologies, but also has a philosophy of maintaining legacy compatibility and enabling smooth transitions to next-generation interfaces.
Inductive Load Switching Suppression Methods: Increasing Military and Aerospace Applications Reliability2008-01-287611/11/2008
This paper will illustrate how the increasing electrical demands of military and aerospace applications can successfully be met by high performance electromechanical relays. To meet these higher demands engineering compatibility between the intended application and relay switching performance parameters must be properly understood. One of the critical parameters are inductive loads which generate transients that can adversely effect relays at the component level and the military or aerospace application at the higher systems levels. In this paper the impact of several methods of inductive suppression are explored. Diode, zener diode, transient voltage suppressors all provide methods to control polarity and voltage levels generated by collapsing magnetic fields in deenergized inductive devices. Each has strengths and benefits that will be further understood by expanding upon their construction, functionality and electrical performance parameters during implementation in switching inductive relay coils in military and aerospace applications.
Baldwin, Michael
The Interplanetary Overlay Networking Protocol AcceleratorTBMG-331710/1/2008
A document describes the Inter - planetary Overlay Networking Protocol Accelerator (IONAC) — an electronic apparatus, now under development, for relaying data at high rates in spacecraft and interplanetary radio-communication systems utilizing a delay-tolerant networking protocol. The protocol includes provisions for transmission and reception of data in bundles (essentially, messages), transfer of custody of a bundle to a recipient relay station at each step of a relay, and return receipts.
CONTACTS, ELECTRICAL CONNECTOR, SOCKET, CRIMP REMOVABLE (FOR MIL-S-12883/44, MIL-S-12883/45, MIL-S-12883/46, AND MIL-R-6106/23 RELAY)AS39029/101 (Historical)4/9/2008
AE-8C1 Connectors Committee
Activating STAT3 Alpha for Promoting Healing of NeuronsTBMG-27224/1/2008
A method of promoting healing of injured or diseased neurons involves pharmacological activation of the STAT3 alpha protein. Usually, injured or diseased neurons heal incompletely or not at all for two reasons: (1) they are susceptible to apoptosis (cell death); and (2) they fail to engage in axogenesis — that is, they fail to re-extend their axons to their original targets (e.g., muscles or other neurons) because of insufficiency of compounds, denoted neurotrophic factors, needed to stimulate such extension. The present method (see figure) of treatment takes advantage of prior research findings to the effect that the STAT3 alpha protein has anti-apoptotic and pro-axogenic properties.
Contacts, Electrical Connector, Socket, Crimp Removable (for MIL-C-26482 Series 2, AS81703 Series 3, MIL-C-83723 Series I and III, and MIL-C-83733 Connectors and MIL-S-12883/40 and /41 Relay Sockets)AS39029/5A_A1 (Historical)3/3/2008
Amendment 1 of AS39029/5A.
AE-8C1 Connectors Committee
Signal Processing System Supplied For NASA’s SCaN ProgramTBMG-240211/1/2007
VXS-based satellite communications development system TEK Microsystems Chelmsford, MA 978-244-9200 www.tekmicro.com
SiC Multi-Chip Power Modules as Power-System Building BlocksTBMG-11732/1/2007
The term “SiC MCPMs” (wherein “MCPM” signifies “multi-chip power module”) denotes electronic power-supply modules containing multiple silicon carbide power devices and silicon-on-insulator (SOI) control integrated-circuit chips. SiC MCPMs are being developed as building blocks of advanced expandable, reconfigurable, fault-tolerant power-supply systems. Exploiting the ability of SiC semiconductor devices to operate at temperatures, breakdown voltages, and current densities significantly greater than those of conventional Si devices, the designs of SiC MCPMs and of systems comprising multiple SiC MCPMs are expected to afford a greater degree of miniaturization through stacking of modules with reduced requirements for heat sinking. Moreover, the higher-temperature capabilities of SiC MCPMs could enable operation in environments hotter than Si-based power systems can withstand.
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