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Technical Paper

“Model Based Predictive Control of MELISSA Photobioreactors. Steady State Determination”

1994-06-01
941411
Mathematical modeling and control of artificial ecosystems, such as MELISSA, require first the study of physical and biological characteristics in optimal and limiting conditions. Following the previous determination of the stoichiometric equations (Spirulina compartment) and regarding the two phototrophic compartments of MELISSA (Rhodospirillaceae and Spirulina), we have first to focus our control study on the growth kinetics for the light source. In this paper, we recall the theoretical equations of microbial growth kinetics and emphasise the problem of the light transfer in a photobioreactor. We present their adaptations to our pilot plant taking into account technological and biological specifics (lamp spectrum, working illuminated volume, growth rate,…). We then develop the principles and structure of the control system and describe tests of both the hardware and software for several steady state configurations.
Technical Paper

“Jet Air” Compressor Control System

1971-02-01
710203
This paper describes the interrelated controls for automatic start sequencing, fuel scheduling, customer air delivery, and supervisory and protective systems as applied to the Curtiss-Wright CW657E “Jet-Air” Compressor. Model CW657E is capable of delivering 15,000 SCFM air at 85 psig (at 30°F and sea level pressure) and may be used in a diversity of manufacturing, processing, and industrial applications. A description of the control system and its operation in relation to compressor requirements, while furnishing air to feed distribution lines to air assisted water atomizing nozzles for snow making is reviewed as an example. Other models can deliver up to 30,000 SCFM with modified control systems, including pressure controls.
Technical Paper

“All Electric” Controls and Accessories for Ground Vehicle Gas Turbine Propulsion Systems

1986-02-01
860238
This paper discusses the use of electromechanical devices as the kinematic portions of a microprocessor based gas turbine control system. Specific applications are: 1. An electric motor driven, positive displacement pump, which provides metered high pressure fuel to the distribution manifold. Fuel metering to be provided by varying the motor angular velocity. 2. An electric motor driven lube oil pump. 3. Electromechnical actuators for motion and control of compressor and power turbine variable geometry. 4. A starter/generator integral with the gas generator. Topics covered include: Comparison to conventional hydro-mechanical systems. Response characteristics of the fuel pump and actuator systems. Brushless D.C. motor characteristics. Power electronics requirements for brushless D.C. motors. Control electronics interface with brushless D.C. motor systems. Reliability and maintainability issues. Diagnostic/prognostic enhancements.
Technical Paper

‘Wheel Slip-Based’ Evaluation of Road Friction Potential for Distributed Electric Vehicle

2016-04-05
2016-01-1667
As a typical parameter of the road-vehicle interface, the road friction potential acts an important factor that governs the vehicle motion states under certain maneuvering input, which makes the prior knowledge of maximum road friction capacity crucial to the vehicle stability control systems. Since the direct measure of the road friction potential is expensive for vehicle active safety system, the evaluation of this variable by cost effective method is becoming a hot issue all these years. A ‘wheel slip based’ maximum road friction coefficient estimation method based on a modified Dugoff tire model for distributed drive electric vehicles is proposed in this paper. It aims to evaluate the road friction potential with vehicle and wheel dynamics analyzing by using standard sensors equipped on production vehicle, and fully take the advantage of distributed EV that the wheel drive torque and rolling speed can be obtained accurately.
Technical Paper

eROSITA Camera Low Temperature Thermal Control

2008-06-29
2008-01-1957
eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is a powerful X-ray telescope under development by the Max-Planck-Institut für extraterrestrische Physik (MPE) in Garching, Germany. eROSITA is the core instrument on the Russian SRG1 mission which is planned for launch in 2011. It comprises seven nested Wolter-I grazing incidence telescopes, each equipped with its own CCD camera. The mirror modules have to be maintained at 20°C while the cameras are operated at -80°C. Both, mirrors and CCDs have to be kept within tight limits. The CCD cooling system consists of passive thermal control components only: two radiators, variable conductance heat pipes (VCHP) and two special thermal storage units. The orbit scenario imposes severe challenges on the thermal control system and also on the attitude control system.
Technical Paper

Zinc-Chloride Electric EngineTM Unit for Four-Passenger Electric Vehicle

1981-02-01
810416
Energy Development Associates, a division of Gulf+Western Industries, Inc., has undertaken the design and fabrication of a four-passenger electric car incorporating state-of-the art zinc-chloride battery technology. The purpose of the project is to demonstrate the viability of the zinc-chloride energy storage system as a practical alternative to cars powered by internal combustion engines. Significant among the project goals to be achieved is the attainment of a vehicle range three to four times that of current lead-acid battery-powered vehicles on a single battery charge. Progress to date on the project is discussed. It includes the design, specification, and fabrication of the battery, vehicle and its components, motor control system, and battery control microprocessor.
Technical Paper

Yaw Rate Sensor for Vehicle Dynamics Control System

1995-02-01
950537
From the beginning of 1995 on, RB will start the production of the Vehicle Dynamics Control System. A key part of this system is the Yaw Rate Sensor described in this paper. The basic requirements for this sensor for automotive applications are: mass producibility, low cost, resistance against environmental influences (such as temperature, vibrations, EMI), stability of all characteristics over life time, high reliability and designed-in safety. Bosch developed a sensor on the basis of the “Vibrating Cylinder”. The sensor will be introduced into mass production in beginning of 1995.
Technical Paper

Xtreme Make-Over In 24 Hours

2005-05-16
2005-01-2550
Our conference chairman told me that this special technical section was structured to provide “some words of wisdom from the old guys” or something to that effect. I know I can meet most of his requirements. I am a pensioner and an oak tree. However, “words of wisdom” maybe a challenge. Solving noise problems, setting acoustical performance targets and guidelines, and developing noise control systems for new and carry-over vehicles can be very challenging and time consuming particularly in today's culture. In the 1970's and 80's, and 90's we had the same challenges. Our customers demanded and appreciated a quiet vehicle. They want to talk to each other without shouting or to enjoy a favorite music selection regardless of weather, road conditions, or vehicle speed. The use of ear plugs or cotton is not acceptable! Noise Gremlins (Figure 1) can ruin a good day!
Technical Paper

Xerox's Distributed Real Time Control System

1987-02-01
870517
XEROX has developed and implemented a network architecture for a real time control system which has expansion flexibility, high reliability, noise immunity, and low cost. This two level multiplex system with a single wire system bus at one level for distributed processors connected to local serial buses at the second level for remote functions and loads is described. The XEROX Microelectronics Center has developed a set of custom VLSI chips to implement the multiplexing architecture. Control software was developed using both assemblers and high level language tools. The software and chip set have been designed, built and integrated into XEROX'S latest generation of products.
Technical Paper

X-29A Subsystems Integration - An Example for Future Aircraft

1988-10-01
881504
The X-29A is the first X-series experimental aircraft developed in the United States since the mid-sixties. The X-29A is a technology demonstrator aircraft that integrates several different-technologies into one airframe. Among the technologies demonstrated are the aeroservoelastically tailored composite forward swept wings, close coupled canards, discrete variable camber wing, triplex digital flight control system with analog backup, thin supercritical wing, three surface pitch control, large negative static margin and the integration of these technologies into the X-29 airframe. This paper deals with the issue of technology integration of five of the X-29A subsystems and the early design decision to use existing aircraft, components whenever and wherever possible. The subsystems described are the X-29 aircraft Hydraulics System, the Electrical Power System, the Emergency Power System, the Aircraft Mounted Accessory Drive and the Environmental Control System.
Technical Paper

Working Fluid De-freezing in Radiator on Base of LHP

2007-07-09
2007-01-3199
Selection of working fluid is one of the main criterions for designing of heat pipes thermal control systems (TCS) for space application. In this paper we will describe how we solved the task of development of the TCS with working fluid of high thermal physical properties. In 2004-2006 we developed the Engineering model of Deployable Radiator based on Loop Heat Pipe by CAST purchase order. It was developed for qualification tests. Ammonia application as LHP working fluid is stipulated by its high thermal physical properties. However Ammonia freezing temperature is of minus 77ºC. Such fact impedes Ammonia application when operation temperatures of LHP Radiator are lower than this value, for example, It takes several tens of hours to orbit a spacecraft and prepare it for work (at that moment the spacecraft is out of power supply) and the working fluid can be frozen in a condenser-radiator when the spacecraft being in the shadow over a long period of time.
Standard

Wireless Power Transfer for Light-Duty Plug-In/Electric Vehicles and Alignment Methodology

2017-11-27
HISTORICAL
J2954_201711
The SAE Recommended Practice J2954 establishes an industry-wide specification that defines acceptable criteria for interoperability, electromagnetic compatibility, EMF, minimum performance, safety and testing for wireless charging of light duty electric and plug-in electric vehicles. The current version addresses unidirectional charging, from grid to vehicle, but bidirectional energy transfer may be evaluated for a future standard. The specification defines various charging levels that are based on the levels defined for SAE J1772 conductive AC charge levels 1, 2, and 3 with some variations. A standard for wireless power transfer (WPT) based on these charge levels will enable selection of a charging rate based on vehicle requirements, thus allowing for better vehicle packaging, and ease of customer use. The specification supports home (private) charging and public wireless charging.
Standard

Wireless Power Transfer for Light-Duty Plug-In/ Electric Vehicles and Alignment Methodology

2016-05-26
HISTORICAL
J2954_201605
SAE TIR J2954 establishes an industry-wide specification guideline that defines acceptable criteria for interoperability, electromagnetic compatibility, minimum performance, safety and testing for wireless charging of light duty electric and plug-in electric vehicles. The current version addresses unidirectional charging, from grid to vehicle, but bidirectional energy transfer may be evaluated for a future standard. The specification defines various charging levels that are based on the levels defined for SAE J1772 conductive AC charge levels 1, 2 and 3, with some variations. A standard for wireless power transfer (WPT) based on these charge levels will enable selection of a charging rate based on vehicle requirements, thus allowing for better vehicle packaging, and ease of customer use. The specification supports home (private) charging and public wireless charging.
Standard

Wire Fed Plasma Arc Directed Energy Deposition Additive Manufacturing Process

2019-01-31
CURRENT
AMS7005
This specification establishes process controls for the repeatable production of preforms by Wire Fed Plasma Arc Directed Energy Deposition (PA-DED). It is intended to be used for aerospace parts manufactured using Additive Manufacturing (AM) metal alloys, but usage is not limited to such applications.
Technical Paper

Wind Tunnel and Flight Development of Spoilers for General Aviation Aircraft

1975-02-01
750523
Wind tunnel tests have been carried out to develop a spoiler lateral control system for use with the GA(W)-1 airfoil with a 30% Fowler flap. Tests show that unfavorable aerodynamic interactions can occur between spoiler and flap for large flap deflections. Providing venting of lower surface air through the spoiler opening substantially improves performance. Results of tests with a number of spoiler and cavity shapes are presented and discussed. Applications of two-dimensional wind tunnel results to the design of satisfactory manual lateral control systems are discussed.
Technical Paper

Why Companies Use Air Freight — A Basic Consideration in Air Freight Systems Planning and Traffic Forecasting

1964-01-01
640531
Use of air freight depends not on the commodity or industry, as such, but on the combinations of characteristics that enable company to benefit from air shipment in any particular situation. Air freight handling and control systems should augment, not decrease, these benefits. Future air freight traffic must be forecast in terms of the different benefits sought in shipping by air. Research is required to determine the relative importance of different benefits in future traffic generation. Research areas are defined and cooperative research efforts urged.
Technical Paper

Who Needs Avionics Performance Minimums - The Government or You?

1968-04-03
680214
A lengthy effort to develop the minimum operational requirements of avionics systems needed for participation in the air traffic control system has not yet yielded standards or a means of administration acceptable to all segments of aviation. A new, more palatable approach by which users of the airspace can provide certain minimum operational characteristics in their airborne electronic systems shows promise. In order to make it work, FAA must clearly describe its electronic systems, how they work, and what their limitations are, so that willing participants may find out what they need to do in order to be right. Based on these system standards, minimum operational characteristics of airborne avionics can be developed and implemented. These may then meet with the approval of most of those affected, since the requirements will merely represent their own self-interest.
Technical Paper

Wheel Lock Control Braking System

1974-02-01
741083
Automobile and truck manufacturers have given increasing attention to electronic wheel lock control brake systems during the last few years. These systems prevent continuous wheel lock-up during maximum braking stops, thus aiding the driver in retaining lateral stability and generally improving stopping distances. This presentation discusses a system for preventing continuous rear wheel lock-up of an automobile during maximum braking stops. Included is a description of the control system components, tire and road characteristics, brake and vehicle dynamics, and an analysis leading to the requirements for optimum control.
Technical Paper

What's Next in Commercial Aircraft Environmental Control Systems?

1993-07-01
932057
Before considering the future of aircraft environmental control systems (ECS's), a review of the relatively short history of this field would be valuable in understanding the present situation. Therefore, this paper notes many of the significant developments in commercial aircraft air-cycle refrigeration and in cabin environmental control. The evolution leading to the great variety of air-cycle systems now in production, or under development, is discussed along with a generic comparison of the merits of the various system types and some reasons for their selection. Constraints on air conditioning system development imposed by the airline operators, aircraft manufacturers, and regulatory agencies are touched upon as significant to charting the future direction of air conditioning system design. Finally, several directions that could be taken in future design are briefly commented upon.
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