Browse Topic: Relays
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MIT engineers are taking a modular approach with a LEGO-like design for a stackable, reconfigurable artificial intelligence chip. The design comprises alternating layers of sensing and processing elements, along with light-emitting diodes (LED) that allow for the chip’s layers to communicate optically. Other modular chip designs employ conventional wiring to relay signals between layers. Such intricate connections are difficult if not impossible to sever and rewire, making such stackable designs not reconfigurable
MIT engineers are taking a modular approach with a LEGO-like design for a stackable, reconfigurable artificial intelligence chip. The design comprises alternating layers of sensing and processing elements, along with light-emitting diodes (LED) that allow for the chip’s layers to communicate optically. Other modular chip designs employ conventional wiring to relay signals between layers. Such intricate connections are difficult if not impossible to sever and rewire, making such stackable designs not reconfigurable
To solve the problems of power quality and phase-links of the high-speed and heavy-load electrified railways power supply system, this paper presents a traveling wave-based directional protection for continuous co-phase autotransformer traction power supply system (TPSS). Basically, phase-mode transformation is used to decouple the transient fault signals to get aerial mode components and then the forward and inverse traveling wave is obtained by calculating the aerial mode components. The variational mode decomposition (VMD) method has no mode confusion and can obtain the accurate instantaneous amplitude and frequency, so it is used to extract the intrinsic mode function (IMF) components, which are further calculated to get the modulus maxima. Two relays at the ends of the protected catenary are used to detect internal and external faults. Consequently, a continuous co-phase traction autotransformer TPSS is modeled in PSCAD/EMTDC, and various faults are simulated to verify the
Missions for small unmanned aircraft (Group 1 and Group 2) include over-the-hill surveillance and providing airborne communications relay points. Greater endurance is almost universally desired by operators to increase the time spent on-station performing the mission and reduce the number and frequency of takeoffs and landings
This SAE Aerospace Information Report (AIR) is intended to provide guidelines to tightening methods and torque values as applied to electrical connectors, related hardware and switches, relays, circuit breakers and A-A-59125 type terminal boards. The connectors and associated hardware discussed herein, are typically manufactured from aluminum alloy, high grade engineering thermoplastics or corrosion resistant steel and typically plated with a protective/conductive coating. These guidelines may be used where no rules have been mandated either contractually or otherwise
The scope of this SAE Recommended Practice is to describe a design standard to define the maximum recommended voltage drop for starting motor main circuits, as well as control system circuits, for 12- through 24-V starter systems
This SAE Recommended Practice covers the design and application of primary on-board wiring distribution system harnessing for surface vehicles. This document is intended for single phase nominal 120 VAC circuits that provide power to truck sleeper cab hotel loads so that they may operate with the main propulsion engine turned off. The power supply comes from alternative sources such as land-based grid power, DC-AC inverters and auxiliary power generators. The circuits may also provide power to improve vehicle performance through charging batteries or operating cold-weather starting aids
This SAE Aerospace Recommended Practice (ARP) provides information to guide in the selection of electromechanical relays to be used in electrical/electronic circuits for application in aerospace, ground, and shipboard systems to achieve proper performance
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
This SAE Recommended Practice is applicable to all liquid-to-gas, liquid-to-liquid, gas-to-gas, and gas-to-liquid heat exchangers used in vehicle and industrial cooling systems. This document outlines the tests to determine durability characteristics of the heat exchanger under pressure cycling
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
Efficient support of planetary surface missions typically requires an orbiting asset that acts as a relay point to/from Earth. Orbital relay passes are normally 5 to 15 minutes in duration over any specific landed site. When multiple landed assets are co-located or near-located in the same coverage circle of a single relay orbiter, their telecom relay support opportunities will overlap. This will be the case with cooperative lander missions, a lander-rover operations pair, distributed intelligent lander missions, and future deployment of multiple equipment components for support of complex sample return or manned operations. In these situations, the capability of simultaneous support to multiple landers is very valuable for mission performance and operations flexibility. This technology work enables simultaneous telecom support to multiple landers (Mars, Titan, Europa), and provides single-radio, multi-mode support to Entry, Descent & Landing (EDL) and emergency operations (e.g
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
In order to transmit communications through Earth’s atmosphere, satellites and space vehicles need radio equipment that can operate at higher frequencies than on Earth. These higher frequencies, until recently, have demanded mechanical switches in radio relays. Unfortunately, the mechanical switches had some problems with frequency routing, which inspired NASA to seek more rugged, reliable solutions
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
Mars rovers and other landers typically use UHF relay to return their science and engineering data to Earth. Direct-To-Earth (DTE) communications are typically used for commanding. If future UHF relay capability becomes diminished, Mars landers may be forced to use DTE communications to meet their data return requirements. An augmented DTE capability with a high-gain antenna and a higher-power transmitter are required to support the relatively high data volume returned in a typical mission. The research for this innovation has developed an antenna architecture that can support such an augmented DTE capability. This antenna architecture comprises an array of microstrip patch subarrays fed by a waveguide corporate feed network, producing a net gain of 30 dBic at the array input
The scope of this SAE Recommended Practice is to describe a design standard to define the maximum recommended voltage drop for starting motor main circuits as well as control system circuits for 12V through 24V starter systems
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
In modern vehicles, the number of small electrical drive systems is still increasing continuously for blowers, fans and pumps as well as for window lifts, sunroofs and doors. Requirements and operating conditions for such systems varies, hence there are many different solutions available for controlling such motors. In most applications, simple, low-cost DC motors are used. For higher requirements regarding operating time and in stop-start capable systems, the focus turns to highly efficient and durable brushless DC motors with electronic commutation. This paper compares various electronic control concepts from a semiconductor vendor point of view. These concepts include discrete control using relays or MOSFETs. Furthermore integrated motor drivers are discussed, including system-on-chip solutions for specific applications, e.g. specific ICs for window lift motors with LIN interface. In most cases, system suppliers have the choice between several electronic partitioning concepts, based
The assembling accuracy of two contactors during the relay switch production is an important factor affecting the quality of relay. An embedded machine vision quality Inspection system has been developed for electric relay production line inspection. The proposed system can provide online feedback on the quality of the relays by measuring the distance of the gap between the contacts of them. Two CMOS imaging sensors are operated for image acquisition and the parallel working mode is realized under dual-channel mode. A red light illumination system has been adopted to eliminate the imaging noise from the reflection of the surfaces of copper sheet. Before the test, the features areas in the image of same type relay is selected as template and saved in the computer. During the inspection procedure, a rotation invariance detection scheme based on circular projection matching algorithm has been used for fast recognizing and locating detected object with the help of these feature areas
Driving loads such as electric motors, relay coils, and solenoids requires a relatively large initial pull-in or start-up current from a driver in order to initiate operation of the load. To maintain continuous operation, the hold or running operating current required for a load may be 20% or less of the initial pull-in or startup current. The problem is that a standard driver circuit acting as a switch continues to provide the same current throughout operation, wasting energy, and must be large enough to provide the large current continuously
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
The Mars Relay Operational Service (MaROS) comprises a number of tools to coordinate, plan, and visualize various aspects of the Mars Relay network. These levels include a Web-based user interface, a back-end “ReSTlet” built in Java, and databases that store the data as it is received from the network. As part of MaROS, the innovators have developed and implemented a feature set that operates on several levels of the software architecture
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