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Journal Article

ℒ1 Adaptive Flutter Suppression Control Strategy for Highly Flexible Structure

2013-09-17
2013-01-2263
The aim of this work is to apply an innovative adaptive ℒ1 techniques to control flutter phenomena affecting highly flexible wings and to evaluate the efficiency of this control algorithm and architecture by performing the following tasks: i) adaptation and analysis of an existing simplified nonlinear plunging/pitching 2D aeroelastic model accounting for structural nonlinearities and a quasi-steady aerodynamics capable of describing flutter and post-flutter limit cycle oscillations, ii) implement the ℒ1 adaptive control on the developed aeroelastic system to perform initial control testing and evaluate the sensitivity to system parameters, and iii) perform model validation and calibration by comparing the performance of the proposed control strategy with an adaptive back-stepping algorithm. The effectiveness and robustness of the ℒ1 adaptive control in flutter and post-flutter suppression is demonstrated.
Technical Paper

“Web-ACSYNT”: Conceptual-Level Aircraft Systems Analysis on the Internet

1997-10-01
975509
A Web-based version of the aircraft design program ACSYNT has been created. “Web-ACSYNT” provides the user with a familiar user interface and is accessible from multiple platforms. Analyses are based upon a set of baseline aircraft models which can be modified through a carefully selected set of parameters related to weight, aerodynamics, propulsion, economics, and mission. The software is intended to become one of the models that comprise the Aviation System Analysis Capability (ASAC) currently being developed by NASA under the Advanced Subsonic Technology (AST) program.
Technical Paper

“Spacematic” Monitoring System

1998-09-15
982138
Pneumatic, manually operated, drilling machines are used to produce a significant proportion of all holes drilled during wing manufacture. Drilling machine design and the manual drilling process has not changed significantly in decades. By employing miniature, low power, electronics and interfacing techniques, a monitoring system has been developed. This system enables improved process control of the manual drilling operation. Machine calibration management, measurement of drill performance, jig drilling error control and asset management are some of the benefits attainable. This project will hopefully encourage others to discover the potential for improving historically established processes, by employing modern technological developments.
Technical Paper

“RoHS” Compliant Chrome - Free Conversion Coating for Aerospace Manufacturing

2006-09-12
2006-01-3130
This paper presents, chemistry, test data and processing procedures on a non toxic and environmentally friendly chrome-free conversion coating alternative with the same level of adhesion and secondary corrosion resistance as that found in chrome containing conversion coating systems. Test data from military and independent sources will be presented on secondary coating adhesion, electrical conductivity, filiform and neutral salt-spray corrosion resistance as compared to chromate based systems .on magnesium, aluminum and zinc and their respective alloys. The European “RoSH” initiative will not allow for the presence of any hexavalent chromium on imported electrical components as of July first of 2006. Trivalent chromium based systems generate hexavalent chromium due to the oxidation of the trivalent chromium and as such will not be allowed.
Technical Paper

“One-Side Aluminized Steel Sheet” Development and Properties of a New Anti-Corrosion Material

1983-02-01
830519
Nisshin Steel Co., Ltd. has developed a new process for the production of a “one-side aluminized steel sheet”. The process utilizes a double layer one-side “stop-off” coating to prevent the molten Al from adhering to the steel surface. The “Stop-off” coating is removed by simple mechanical brushing after hot dipping. The characteristics of this product by above mentioned process are: 1) The steel side was as clean as a conventional cold rolled surface and showed no trace of the “stop-off” layer. Thereby, phosphating and ED painting were performed. 2) In the salt spray test data was obtained from zinc and Al coated steel surfaces; the coatings on both surfaces being of equal thickness.
Technical Paper

“Next Generation” Means for Detecting Squeaks and Rattles in Instrument Panels

1997-05-20
972061
Engineers doing squeak and rattle testing of instrument panels (IP's) have successfully used large electrodynamic vibration systems to identify sources of squeaks and rattles (S&R's). Their successes led to demands to test more IP's, i.e., to increase throughput of IP's to reflect the many design, material, and/or manufacturing process changes that occur, and to do so at any stage of the development, production, or QA process. What is needed is a radically different and portable way to find S&R's in a fraction of the time and at lower capital cost without compromising S&R detection results.
Technical Paper

“Metallic Core Technology”…and the Production of One Piece, Hollow Composite Components Which Have Complex Internal Geometry

1992-02-01
920507
Engineers have long been restricted in designing and manufacturing one piece, hollow composite components with complex internal geometry. Complex core pulls in the plastic tool, major concessions made in the actual component design or components joined from several pieces were the early means of producing such components. Progressive thinking led to the use of matrix materials such as sand, salt and wax, which provided a measure of flexibility in allowing designed-in undercut areas. These materials, however, lacked the capability to meet the required demands of dimensional accuracy and internal surface, as well as proving themselves unsuitable for high volume production. The concerns for repetitive dimensional accuracy, quality internal surface and high volume production capability has now been satisfied with the use of low melting temperature metal alloys.
Technical Paper

“Mechanical Brake Assist - A Potential New Standard Safety Feature”

1999-03-01
1999-01-0480
This paper presents an innovative brake booster which permits the brake assist function of the electric brake assist system to be implemented with mechanical means. The resultant significant reduction of manufacturing costs enhances the chances for a wide-spread use of this feature in all vehicle classes, thereby making an important contribution to the general improvement of traffic safety. Based on an analysis of the mechanically detectable physical variables for recognizing a panic situation and an evaluation of possible methods of mechanical valve activation, the paper presents a mass production solution and describes its functional properties. In particular, it should be noted that the possibility of controlling the braking pressure within the brake assist function even represents a functional advantage
Technical Paper

“MONOGAL”: A New Anti-Corrosion Material for the Automotive Industry

1982-02-01
820335
MONOGAL is a coated steel developped to improve the corrosion resistance of exposed automotive body applications. Its process os based on the brittleness of the η zinc coating in a range of temperatures below the melting point of the zinc. MONOGAL is produced on a hot dip galvanizing line; at the exit of the pot the free zinc is brushed off the light side of the differentially coated sheet. Side 1 of MONOGAL presents a very thin and continuous layer of iron-zinc diffusion alloy with no free zinc. Side 2 is a standard G90 or G60 zinc coating. The iron-zinc alloy layer has excellent anti-galling properties which improve the formability of MONOGAL over two side hot dip galvanized steel with the same r value. MONOGAL also shows good weldability, paintability and corrosion resistance.
Technical Paper

“Investigation of High Achievable Pollutant Reduction on a “State of the Art” Indian 2 Wheelers - Technology Road Map to a Cleaner Air”

2015-11-17
2015-32-0802
Affordable, efficient and durable catalytic converters for the two and three wheeler industry in developing countries are required to reduce vehicle emissions and to participate in a cleaner and healthier environment. As a contribution Continental Emitec started a comprehensive testing program with a state of the art 180 cc Bharat Stage (BS) III Indian motorcycle. The program consists of testing the state of the art of Metallic substrates with structured foils with various catalyst sizes and positions (original or close coupled). The publication presents a short literature survey and the results of the investigation with a big catalyst volume mounted in underfloor position as well as in close coupled position, gained over the World-wide harmonized Motorcycle Test Cycle, considering the two possible vehicle classifications of this motorcycle, Sub-Class 2.1 and Sub-Class 2.2.
Technical Paper

“Impact of Design Principles on End-of-Life and Recycling”

2024-01-16
2024-26-0163
Automotive industry is a major contributor to global carbon dioxide (CO2) emissions and waste generation. Not only do vehicles produce emissions during usage, but they also generate emissions during production phase and end of life disposal. There is an urgent need to address sustainability and circularity issues in this sector. This paper explores how circularity and CO2 reduction principles can be applied to design and production of automotive parts, with the aim of reducing the environmental impact of these components throughout their life cycle. Also, this paper highlights the impact of design principles on End-of-Life Management of vehicles. As Design decisions of Component impacts up to 80% of emissions [1], it is important to focus on this phase for major contribution in reduction of emissions.
Technical Paper

“Geometric Dimensioning and Tolerancing”

1968-02-01
680488
Geometric dimensioning and tolerancing is both a “language” and a “technique.” Its objective is to facilitate design, production, and inspection and, simultaneously, provide the most economic results. This paper describes the implementation and practice to accomplish these through illustrating methods to state design requirements specifically and clearly and to provide for maximum producibility, uniformity of interpretation, etc. The need to reflect a common objective for design, production, and inspection via the stated drawing requirement is emphasized. Application and interpretation of geometric characteristics (emphasizing symbology), fundamentals, rules, etc. are presented. Basis for the content of this paper is USASI Y14.5-1966 “Dimensioning and Tolerancing for Engineering Drawings.”
Technical Paper

“DELRIN” ACETAL RESIN —a new engineering material

1959-01-01
590033
“DELRIN” is a new thermoplastic which offers high strength, excellent thermal stability, good fatigue life, low creep, and excellent solvent resistance. This paper describes the physical and chemical properties of the material, and the range of possible uses. The material is easily fabricated into complex shapes by standard injection-molding techniques. Also, it can be easily joined to itself or to other materials. The authors think that the material offers advantages over metals in its good fric-tional properties, abrasion resistance, and corrosion resistance.
Technical Paper

“Cromard” Thin Wall Steel Liners and Hard Chrome Plated Liners for High Production Gasoline and Diesel Engines

1964-01-01
640361
This paper, confined to the application of hard chrome plated liners to high-speed four-stroke diesel and gasoline engines, illustrates the increase in their popularity in the United Kingdom, and the advanced production methods which make this economically possible. The need for balanced engine life has long been apparent and is even more important today, the growth of motor transport having outstripped repair facilities. Iron bore life has been surpassed by improvement in the life of other component parts in the modern diesel engine. The provision of hard chrome plated liners can restore the balance. Further development and turbocharging of diesel engines has shown the need for a bore material capable of preventing scuffing and galling at elevated temperatures. Hard chrome has already proved itself in four-stroke engines under these conditions.
Technical Paper

“Converticar” - The Roadable Helicopter

1998-09-28
985513
The Boeing Company in Mesa, Arizona, has been conducting a concept design study of a roadable helicopter called the “Converticar” to assess its feasibility. This is a twin-engine vehicle with twin retractable coaxial counter-rotating rotors. The purpose of the study is to describe a vehicle that carries four passengers in the equivalent of a luxury car that also can fly like a helicopter, and can be priced like a luxury car. To come near this cost goal, the production rate must be on the order of 500,000 units a year. At that rate there is no chance of training a comparable number of pilots each year. So the machine must fly and navigate autonomously, with the pilot just dialing in where he/she wants to go. Technologically, the concept appears to be feasible. Modern design processes, new materials, and improved manufacturing process should allow the Converticar to be built at the prescribed rate when the proper infrastructure for manufacturing it is made available.
Technical Paper

“Concept to Concrete” Development of a Truck Type Street Sweeper

1979-02-01
790879
A new truck type street sweeper has been developed which incorporates some of the sweeping advantages of a three wheeled sweeper (tricycle steer) and the transport advantages of a legal highway truck. It offers major productivity improvements through better operator environment and decrease of nonsweeping time in the operational cycle. It is possible for a small “short line” special purpose vehicle manufacturer to develop, test, and produce such a vehicle and meet Federal regulatory requirements with limited “In house” design and testing facilities. Here this was accomplished through judicious augmentation by outside specialized design and testing organizations.
Technical Paper

“Chip on Glass” Technology for Large Scale Automotive Displays

1984-02-01
840148
Large scale automotive displays e.g., liquid crystal displays, require chip on glass technology at least for the driver-ICs. In this paper different IC-packages, metallization, bonding and encapsulation techniques are compared and conclusions for production methods are drawn.
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