This study aims to solve the problem of impact in a parallel hybrid electric system based on the continuously variable transmission (CVT) during switching from pure electric mode to engine-driven, power-generating mode. Taking into account the torque response characteristics of the engine and motor and the dynamic characteristics of the wet clutch hydraulic control system, the mode switching process is divided into six stages, namely, pure electric mode, wet-clutch free travel, engine start-up, engine speed synchronization, clutch combination, and engine intervention drive. A coordination control strategy is developed based on the model predictive control algorithm to ensure smooth mode switching. The effectiveness of the control algorithm is verified using Matlab/Simulink and the AMESim co-simulation platform. Results show that with the mode switching coordination control strategy, the components of the system work harmoniously. The maximum impact is reduced by 52.0% at the speed

Zeng, Xiaohua, Li, Xiaojian, Dong, Bingbing

Room-Temperature Magnon Switch

TBMG-3744908/01/2020

Researchers have demonstrated a potentially new way to make switches inside a computer’s processing chips, enabling them to use less energy and radiate less heat. The practical technique controls magnons, which are essentially waves that travel through magnetic materials and can carry information. To use magnons for information processing requires a switching mechanism that can control the transmission of a magnon signal through the device.

Guiding and Harnessing Transition Waves in Multi-Stable Mechanical Structures

TBMG-3636704/01/2020

A deployable structure can transition from a compact state to an expanded one. Such structures usually require rather complicated locking mechanisms to hold them in place. Today’s deployable structures aren’t always reliable or autonomous. Harnessing the domino effect, researchers have designed deployable systems that expand quickly with a small push and are stable and locked into place after deployment.

Photonic Switch Increases Speed and Efficiency of Light Through Optical Fibers

TBMG-3570612/01/2019

A photonic switch was developed that can control the direction of light passing through optical fibers faster and more efficiently than ever. This optical “traffic cop” could improve how information travels through high-performance supercomputers used for artificial intelligence and other data-intensive applications.

Simulation Analysis of Single-Phase Matrix Converter for Cycloconverter Operation Using SPWM with Under and Over Modulation Technique

2019-28-012010/11/2019

This paper discusses the implementation of ac-ac converter using a matrix converter. A MATLAB Simulink model of single-phase matrix converter has been developed for matrix converter with a step up and step down of input frequency. Selection of power switches differentiates the conventional cycloconverter from that of matrix converter based cycloconverter. Conventional cycloconverters requires thyristors whereas matrix converter based cycloconverter requires IGBT which is formed as a bidirectional switch module. The performance of matrix converter based cycloconverter using Sinusoidal Pulse Width Modulation Technique (SPWM) has been analyzed for resistive and inductive loads at varying frequency. This paper presents the output results for various frequencies such as 12.5 Hz, 25 Hz (step-down operation) and 100 Hz (step-up operation).

Nallathambi, Kalaiarasi, Daniel, Anitha, Rangarajan, Uthra

Guarding of Starter System Energization

J1493_201908 (Current)08/08/2019

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)

Integrated Silicon Photonic Switch Demonstrates Lowest Signal Loss Ever in High-Speed Data Transmission

TBMG-3477007/01/2019

Experimental photonic switches developed at UC Berkeley have shown promise toward the goal of fully optical, high-capacity switching for future high-speed data transmission networks. The switch developed and tested for this research demonstrated capabilities not seen before in photonic switches. Key to this success, is the scale-up of a 240 × 240 integrated silicon photonic switch. The device is so-named because it accepts 240 optical communication input channels and sends them into 240 output channels.

ONR Short Pulse Research, Evaluation and non-SWaP Demonstration for C-sUAV Study

TBMG-3452906/01/2019

The OSPRES (ONR Short Pulse Research, Evaluation and non-SWaP) program performed fundamental work in the areas of Silicon (Si) and Gallium Nitride (GaN) based photoconductive switch development, measurement of HPM waveform dependent effects on small unmanned aerial vehicle (sUAV), adaptive design of experiments, noise injection, RF coupling to sUAV's, minimally dispersive wave theory, and positive feedback non-linear transmission line (NLTL) development.

All-Fiber, Optically Controlled Optical Switch

TBMG-3462206/01/2019

An optical switch is a device where information-bearing light may be directed to one of several outputs. Prior art optical switches have mainly been integrated optical waveguide structures such as titanium-diffused (Ti) waveguides in lithium-niobate (LiNbO3) or gallium-arsenide (GaAs) structures, or other compound semiconductors.

ONR Short Pulse Research, Evaluation and non-SWaP Demonstration for C-sUAV Study

19AERP06_0906/01/2019

Research project is designed to map small unmanned aerial vehicle (sUAV) effects space, empirically and by simulation, as a function of high power microwave (HPM) waveform to develop effective countermeasures. Office of Naval Research, Arlington, Virginia The OSPRES (ONR Short Pulse Research, Evaluation and non-SWaP) program performed fundamental work in the areas of Silicon (Si) and Gallium Nitride (GaN) based photoconductive switch development, measurement of HPM waveform dependent effects on small unmanned aerial vehicle (sUAV), adaptive design of experiments, noise injection, RF coupling to sUAV's, minimally dispersive wave theory, and positive feedback non-linear transmission line (NLTL) development. The photoconductive solid state switch (PCSS) subgroup worked to develop a fundamental understanding of the limitations of Silicon and Gallium Nitride based photoconductive switches and their application to pulsed power. With an estimated 2 megawatts (MW) peak power generation

Understanding the “Black Art” of RF and Microwave Switching

TBMG-3412604/01/2019

Understanding the “Black Art” of RF and Microwave Switching

19AERP04_0604/01/2019

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

MEMS Switch Extends Life of Cellphones

TBMG-3391703/01/2019

A new type of microelectromechanical system (MEMS) was developed that uses electrostatic levitation to provide a more robust system. All cellphones use MEMS switches for wireless communication, but traditionally there are just two electrodes. The switches open and close numerous times during just one hour, but their current lifespan is limited by the two-electrode system.

“Light-Written” Photonic Memory Devices

TBMG-3391103/01/2019

Light is the most energy-efficient way to move information; however, light shows one big limitation: it is difficult to store. Data centers, for example, rely primarily on magnetic hard drives in which information is transferred at an energy cost that is increasing. A hybrid technology was developed that shows advantages of both light and magnetic hard drives.

Gated Chopper Integrator (GCI)

TBMG-3339212/01/2018

Microvolt-level signals require gains of at least a thousand. Offsets and noise in the amplifier chain will be amplified by the same amount, which can saturate the amplifier or swamp the signal so it is not resolvable. Other methods use chopping and/or autozero techniques to lower the offset and noise. The key disadvantages of these methods are they require filters before and/or after demodulation of the amplified signal and delay equalization to account for the delay through the amplifier(s) prior to the demodulator. The gain of these circuits is generally limited to fixed values determined by resistors. These methods are also susceptible to transient noise associated with the switching action of the modulator.

Ferroelectric Switching in 2D Tungsten Produces Spontaneous Electrical Polarization

TBMG-3325911/01/2018

The general public might think of the 21st century as an era of revolutionary technological platforms, such as smart-phones or social media. But for many scientists, this century is the era of another type of platform: two-dimensional materials, and their unexpected secrets.

Polymer Nanofiber-Based Reversible Nano-Switch/Sensor Schottky Diode (nanoSSSD) Device

TBMG-3311710/01/2018

Innovators at NASA's Glenn Research Center have developed a unique nano-structure device that operates as a nano-switch/sensor for detecting toxic gases and ultraviolet (UV) radiation. Conventional microsensors are limited by their short life, high cost and complexity, and unifunctional sensing task. Glenn's novel Polymer Nanofiber-Based Reversible Nano-Switch/Sensor Schottky Diode (nanoSSSD) technology offers the ability to respond to changing conditions and then revert to baseline operations when conditions return to normal. Glenn's nanoSSSD features no mechanical moving parts, and the sensors are reusable after annealing, extending their appeal for rapid-response, low-cost devices. This simple design provides an easily fabricated, mass-producible microsensor for use in numerous applications where replacement opportunities are limited.

Switch Controls Light on a Nanoscale for Faster Information Processing

TBMG-3311110/01/2018

Photons, or units of light, are faster than electrons and could, therefore, process information faster from smaller chip structures. A switch was designed that bypasses a tendency for the unwanted absorption of light when using surface plasmons, or light coupled to oscillations of free electron clouds, to help confine light to a nanoscale. Even though plasmonics downsizes light, photons also get lost, or absorbed, rather than transferred to other parts of the computer chip when they interact with plasmons.

Standard Rainflow File Format

J2623_201808 (Current)

08/24/2018

This SAE Standard provides a definition of a rainflow file format. This type of simple text file would contain all relevant information about the rainflow cycle content of a time history. Included information are Comments, Signal Range, Signal Mean, Number of Cycles, Signal Maximum, Signal Minimum. Rainflow cycle counting has become the most accepted procedure for identifying material fatigue relevant cycles in complex variable amplitude load time histories. The cycle counting methods account for the effects of material plasticity and material memory of prior deformation, and the resulting compressed history information is used by durability analysts to estimate the effects of a given service or test history. Standardization of the rainflow counting methods output files, which is the format addressed by the present standard, is important for reliable information transfer between test and design groups, or different calculation software packages, and thus forms a critical step in the

Materials, Processes and Parts Council

A Packaging Layout to Mitigate Crosstalk for SiC Devices

2018-01-046204/03/2018

SiC devices have inherent fast switching capabilities due to their superior material properties, and are considered potential candidates to replace Si devices for traction inverters in electrified vehicles in future. However, due to the comparatively low gate threshold voltage, SiC devices may encounter oscillatory false triggering especially during fast switching. This paper analyzed the causes of false triggering, and also studied the impact of a critical parasitic parameter - common source inductance. It is shown that crosstalk is the main cause for the false triggering in the case and some positive common source inductance help to mitigate the crosstalk issue. A packaging layout method is proposed to create the positive common source inductance through layout of control terminals / busbars, and/or the use of control terminal bonded wires at different height.

Xu, Zhuxian, Chen, Chingchi, Lei, Thomas

General Requirements for WDM Backbone Networks

AIR6005 (Current)

01/23/2018

This document (AIR6005) provides the framework for the specifications of a WDM OBN within the SAE AS5659 WDM LAN Specification document family, in particular, the Transparent Optical Backbone Network Specification. This framework includes potential requirements, technical background, investigation and context to support the writing of SAE’s WDM LAN specifications documents. The SAE’s AS6005 WDM OBN document describes a transparent optical network which contains optical components and optical interfaces to perform optical transport, optical add/drop, optical amplification, optical routing, and optical switching functions. The conforming optical signal interfaces for the data plane of the WDM OBN are defined. The conforming signal interfaces for the control and management planes of this network are also defined. The control and management plane signals may be either electrical or optical. If successful, a WDM LAN standard is anticipated to include multiple variants that may get created

AS-3 Fiber Optics and Applied Photonics Committee

General Requirements for WDM Backbone Networks

AIR6005-TEST-REC (Historical)01/23/2018

AS-3 Fiber Optics and Applied Photonics Committee

Nanoporous Material Reduces Computer Energy Consumption

TBMG-2816401/01/2018

In order to store information in the conventional magnetic memories of electronic devices, the material’s small magnetic domains are oriented “up” or “down” by using externally applied magnetic fields. To generate these fields, it is necessary to produce electric currents; however, these currents heat up materials, and a large amount of energy is needed to cool them.

3D-Printed Objects Connect to WiFi Without Electronics

TBMG-2816501/01/2018

CAD models have been developed that enable objects to be 3D-printed out of commercially available plastics; these objects can wirelessly communicate with other smart devices, including a battery-free slider that controls music volume, a button that automatically places an order with Amazon, or a water sensor that sends an alarm to a smartphone when it detects a leak.

Silicon Carbide High-Voltage Switch

TBMG-2818001/01/2018

High-voltage wide bandgap (WBG) semiconductor devices like 15-kV silicon carbide (SiC) MOSFETs have attracted attention because of potential applications in high-voltage and high-frequency power converters. These devices, however, are not commercially available, and their high cost due to expensive material growth and fabrication may limit their widespread adoption in the future.

Solder Bond Packaging for High-Voltage Pulsed Power Devices

TBMG-2703406/01/2017

The huge demand for switching components exceeding silicon's (Si) current density limitation of 200 A/cm2 has pushed the enhancement of alternative semiconductor materials such as silicon carbide (SiC), gallium nitride, and diamond. The enhanced material properties of SiC, such as high thermal conductivity, large critical field, wide bandgap, large elastic modulus, and high saturation velocity, make it a viable candidate for pulsed power systems. Using SiC would increase both current and power densities, improve dI/dt and dV/dt capabilities, reduce recovery time, and minimize switching losses in various power electronic systems. Furthermore, a significant reduction in the volume and weight of pulsed power systems can be realized by implementing SiC SGTOs, reducing the thermal management requirements of the pulsed power system.

A Smart Gate Driver with Active Switching Speed Control for Traction Inverters

2017-01-124303/28/2017

The IGBTs are dominantly used in traction inverters for automotive applications. Because the Si-based device technology is being pushed to its theoretical performance limit in such applications during recent years, the gate driver design is playing a more prominent role to further improve the traction inverter loss performance. The conventional gate driver design in traction inverter application needs to consider worst case scenarios which adversely limit the semiconductor devices' switching speed in its most frequent operation regions. Specifically, when selecting the gate resistors, the IGBT peak surge voltage induced by fast di/dt and stray inductance must be limited below the device rated voltage rating under any conditions. The worst cases considered include both highest dc bus voltage and maximum load current. However, the traction inverter operates mainly in low current regions and at bus voltage much lower than the worst case voltage. This paper proposes a low-cost and simple

Zhou, Yan, Chen, Lihua, Yang, Shuitao, Xu, Fan, Alam, Mohammed Khorshed

A First Strategy for Smoothing Transients in Switching Controls of Aerospace and Automotive Systems

2016-36-040210/25/2016

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

Amaral, Jairo Cavalcanti, de Oliveira e Souza, Marcelo Lopes

An Investigation into the Tradespace of Advanced Wide-Band Gap Semiconductor Devices in a Full-Bridge DC-DC Converter

2016-01-199009/20/2016

In aerospace applications, it is important to have efficient, small, affordable, and reliable power conversion units with high power density to supply a wide range of loads. Use of wide-band gap devices, such as Silicon Carbide (SiC) and Gallium Nitride (GaN) devices, in power electronic converters is expected to reduce the device losses and need for extensive thermal management systems in power converters, as well as facilitate high-frequency operation, thereby reducing the passive component sizes and increasing the power density. A performance comparison of state-of-the art power devices in a 10 kW full-bridge dc-dc buck converter operating in continuous conduction mode (CCM) and at switching frequencies above 100 kHz will be presented in this manuscript. Power devices under consideration are silicon (Si) IGBT with Si antiparallel diodes, Si IGBT with SiC antiparallel diodes, Si MOSFETs, SiC MOSFETs, and enhancement-mode GaN transistors. A 10 kW full-bridge dc-dc converter operating

Smith, Nathaniel, Kondrath, Nisha

Interface between Numerical Control Equipment and Data Terminal Equipment Employing Parallel Binary Data Interchange

EIA408 (Current)06/16/2016

This standard applies to the interconnection of data terminal equipment and numerical control equipment at the tape reader interface. The data terminal would typically be connected to a remote data source/sink such as a computer. This standard defines: This standard is applicable for the interchange of signals when used in conjunction with electronic equipment, each interchange circuit of which has a single return (signal ground) that can be interconnected at the interface point. Figure 1.1, typical installation, shows how this standard should be applied to a typical tape reader interface of numerical control equipment.

Systems Management Council

Aerospace & Defense Technology: June 2016

16AERP0606/01/2016

Digital Design Tools Simulating Thermal Expansion in Composites with Expanded Metal Foil for Lightning Protection Rugged Computing Designing VME Power Systems with Standard Modules Optical Sensors Optical Ice Sensors for UAVs Rotorcraft Technology Rotorcraft Icing Computational Tool Development RF & Microwave Technology Curled RF MEMS Switches for On-Chip Design: Design Software Supports BAE System's Mixed-Signal Chip Design

Design and Optimization of a 98%-Efficiency On-Board Level-2 Battery Charger Using E-Mode GaN HEMTs for Electric Vehicles

2016-01-121904/05/2016

Most of the present EV on-board chargers utilize a three-stage design, e.g., AC/DC rectifier, DC to high-frequency AC inverter, and AC to DC rectifier, which limits the wall-to-battery efficiency to ∼94%. To further increase the efficiency and power density, a matrix converter is an excellent candidate directly converting grid AC to high-frequency AC thereby saves one stage. However, its control complexity and the high cost of building the back-to-back switches are barriers its acceptance. Instead, this paper adopts the 650V E-mode GaN HEMTs to build a level-2 on-board charger using the indirect matrix topology. The input voltage is 80∼260VAC, the battery voltage is 200∼500VDC and the rated power is 7.2kW. Variable switching frequency is combined with phase-shift control to realize the zero-voltage switching. To further increase the system efficiency, four GaN HEMTs are paralleled to form one switching module with a novel gate-drive technology. The overall system efficiency is ∼98% and

McAmmond, Matt, Brown, Alan, Bai, Hua, Lu, Juncheng, Tian, Qi, Teng, Hui

Multi-Frequency, THz Quantum Cascade Laser Source

TBMG-2345312/01/2015

Interest in the use of THz detectors outside the laboratory for space, atmospheric, and terrestrial applications has grown immensely in the past half-century. Of particular interest in recent years is the development of the quantum cascade laser (QCL) as a THz frequency source.

Fault Recovery for Multi-Phase Power Converters

TBMG-23241

11/01/2015

A fault recovery method for multiphase power converters enables delivery of reduced output power of as much as 66% of normal power in the event of a shorted power switch component. The need for redundant power converters in conventional multi-phase space power systems is reduced, if not eliminated. Fault recovery includes detecting a shorted power switch fault, providing short circuit current protection, providing isolation of the shorted power switch, and reconfiguring the remaining undamaged power switches.

Displacement Joystick/Thumb Wheel Switch Control Profile for Precision and Jerk Free Speed Control Application in Open Loop System

2015-01-287009/29/2015

Displacement joystick controls are considered as most suitable for manual controls wherever proportional outputs are required for dynamic applications such as when variable speed sensitivity or position are required. These joysticks are being used widely in both open loop as well as in close loop controls. The operator applies force to either the joystick itself or to its proportional linear displacement thumb wheel switches. This movement is then detected by either resistive or Hall Effect sensors, placed right inside joystick, and converted into an electrical signal. These joysticks, along with proportional linear displacement thumb wheel switches, find a wide range of applications in off-road vehicles such construction and forestry vehicles, harvester machines, and etc. for applications like attachment speed controls, boom position control, rotation speed control, and etc. The higher the displacement of the joystick, or its linear displacement thumb wheel switches, the better will

Pawar, Sanket

Integral of Modulus of Error Control for Smoothing Signals when Switching Modes of Aerospace and Automotive Systems

2015-36-044509/22/2015

Control systems that can switch between control or plant modes have the advantage of being simpler to design than an equivalent system with a single mode. However, the transition between these modes can introduce steps or overshootings in the state variables, and this can degrade the performance or even damage the system. This is can be of extreme importance in fields such as aerospace and automobilistic, as the switching between manual and autopilot modes or the switching of gears In this work, we will use integral criteria in original ways, to determine a coefficient on the system which should optimize the trajectory of the control signal, during the switching between two modes. Effectively, each transition will be done by a subsystem specific for it, according to the selected criterion. The simulations will be made in MATRIXx, MatLab or both, using models chosen from aerospace or automobilistic fields.

Amaral, Jairo Cavalcanti, de Oliveira e Souza, Marcelo Lopes

VCSEL Laser Array for Communications

TBMG-22019

05/01/2015

Optical communications in terrestrial and space environments require transmitted signals on the order of 40 GHz and higher, because of the uncertain and changing transmission environments. A robust communications system is needed that will provide these frequencies and substantial discrimination between different signals, which permit switching times on the order of 0.25 ps, and that permit the use of two or more distinct signals.

Negative Dielectric Constant Material Based on Ion-Conducting Materials

TBMG-21408

02/01/2015

Metamaterials, or artificial negative index materials (NIMs), have generated great attention due to their unique and exotic electromagnetic properties. A negative dielectric constant material, which is an essential key for creating the NIMs, was developed by doping ions into a polymer, a protonated poly(benzimidazole) (PBI).

Ethernet Switch and Router Technology

TBMG-2036108/01/2014

Curtiss-Wright Corporation Ashburn, VA 973-541-3700

ASICs Support Orion’s Onboard Data Network

TBMG-2029808/01/2014

TTEthernet switch TTTech North America Andover, MA 978-933-7979

Silicon Carbide Power Processing Unit for Hall Effect Thrusters

TBMG-2032108/01/2014

A high-efficiency, rad-hard, 3.5-kW SiC power supply was developed for the power processing unit (PPU) of Hall effect thrusters. This work specifically targets the design of a PPU power supply for the HiVHAC (High Voltage Hall Accelerator) thruster. The PPU power supply under development utilizes components that were irradiated under TID (total ionizing dose) conditions to greater than 3 Mrad with little to no change in device performance.

Improvised Diagnostic Strategy for High-Side Switch Power Stage

TBMG-1937104/01/2014

A vehicle electronic control unit consists of various high-side power stages for driving different loads. Common faults that these power stages experience are Short Circuit to Battery (SCB), Short Circuit to Ground (SCG), and Open Load (OL). These faults can occur during either on-state or off-state of the power stage output. It is essential to diagnose a fault such as SCB during switch off-state, SCG during switch on-state, and OL during both on- and off-state of the switch in order to avoid system malfunction or power stage damage.

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