Download or read book Ground and Flight Test Structural Excitation Using Piezoelectric Actuators written by and published by . This book was released on 2002 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: A flight flutter experiment at the National Aeronautics and Space Administration (NASA) Dryden Fight Research Center, Edwards, California, used an 18-inch half-span composite model called the Aerostructures Test Wing (ATW). The ATW was mounted on a centerline flight test fixture on the NASA F-15B and used distributed piezoelectric strain actuators for in-flight structural excitation. The main focus of this paper is to investigate the performance of the piezoelectric actuators and test their ability to excite the first-bending and first-torsion modes of the ATW on the ground and in-flight. On the ground, wing response resulting from piezoelectric and impact excitation was recorded and compared. The comparison shows less than a 1-percent difference in modal frequency and a 3-percent increase in damping.
Download or read book Ground and Flight Test Structural Excitation Using Piezoelectric Actuators written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-19 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: A flight flutter experiment at the National Aeronautics and Space Administration (NASA) Dryden Flight Research Center, Edwards, California, used an 18-inch half-span composite model called the Aerostructures Test Wing (ATW). The ATW was mounted on a centerline flight test fixture on the NASA F-15B and used distributed piezoelectric strain actuators for in-flight structural excitation. The main focus of this paper is to investigate the performance of the piezoelectric actuators and test their ability to excite the first-bending and first-torsion modes of the ATW on the ground and in-flight. On the ground, wing response resulting from piezoelectric and impact excitation was recorded and compared. The comparison shows less than a 1-percent difference in modal frequency and a 3-percent increase in damping. A comparison of in-flight response resulting from piezoelectric excitation and atmospheric turbulence shows that the piezoelectric excitation consistently created an increased response in the wing throughout the flight envelope tested. The data also showed that to obtain a good correlation between the piezoelectric input and the wing accelerometer response, the input had to be nearly 3.5 times greater than the turbulence excitation on the wing. Voracek, David F. and Reaves, Mercedes C. and Horta, Lucas G. and Potter, Starr and Richwine, David (Technical Monitor) Armstrong Flight Research Center; Langley Research Center NASA/TM-2002-210724, H-2482, NAS 1.15:210724, AIAA Paper 2002-1349
Download or read book AVST Morphing Project Research Summaries in Fiscal Year 2001 written by Anna-Maria R. McGowan and published by . This book was released on 2002 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the Third World Conference on Structural Control written by Fabio Casciati and published by John Wiley & Sons. This book was released on 2003-03-14 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organized by the International Association for Structural Control(IASC), and sponsored by the European Association for the Controlof Structures (EACS), the recent world conference on structuralcontrol (3WCSC) brought together engineers, scientists, architects,builders and other practitioners interested in the general fieldsof active, hybrid and passive vibration control, health monitoringand damage detection, intelligent/smart materials and systems.Applications included buildings, bridges, space structures andcivil infrastructures under the action of dynamic environments(earthquake, wind, traffic...) and man-made loads. It provideda valuable forum for the discussion of the most pressing concernsin structural control and its related topics. The conference covered a wide range of topics including activeand semi-active control devices, passive control devices, controlalgorithms for linear and non-linear systems, modeling andidentification of structural systems, sensors, health monitoringand damage detection, benchmark test of building and bridges,innovative materials for structural control, applications toaerospace structures, applications to bridges, applications tocritical structures, external dynamic force characteristics andcontrollability issues, implications of severe ground motions, windforces, codes for structural control, and so forth. Suchcomprehensive treatment of the most innovative developments instructural control will make these volumes an informative referencefor all researchers and engineers interested in this area. Proceedings of the US - Europe Workshop On Sensors andSmart Structures Technology Como and Somma Lombardo, Italy In the last few years, significant progress has been made in thearea of sensing technology and structural healthmonitoring/condition assessment in the US and Europe. Innovativeconcepts involving new hardware, algorithms, and software have beenproposed. There have also been several full-scale trialimplementations of densely sensor-instrumented infrastructures andhealth monitoring systems, as well as case studies on bridges inEurope and in the US. Much can be learnt through US/European collaboration in the areaof experimental verification on small, medium, large and full-scaleprojects. Moreover, a common framework for expanded future jointresearch can be developed on the increased understanding achievedthrough mutual learning. This workshop consisted of seminar sessions on several themeswhich included innovative sensing hardware, advances in wirelesstechnology, and damage detection/characterization and conditionassessment methodologies. In addition, there were several workshopsessions devoted to summarizing the status of the sensors and smartstructures technologies in these topics, identifying the compellingresearch issues, and formulating an action plan withrecommendations for development and implementation through possiblecollaborative research projects and sharing of scientific data.
Download or read book The Aeronautical Journal written by and published by . This book was released on 2003 with total page 820 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rotationally Adaptive Flight Test Surface written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-04 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research on a new design of flutter exciter vane using adaptive materials was conducted. This novel design is based on all-moving aerodynamic surface technology and consists of a structurally stiff main spar, a series of piezoelectric actuator elements and an aerodynamic shell which is pivoted around the main spar. The work was built upon the current missile-type all-moving surface designs and change them so they are better suited for flutter excitation through the transonic flight regime. The first portion of research will be centered on aerodynamic and structural modeling of the system. USAF DatCom and vortex lattice codes was used to capture the fundamental aerodynamics of the vane. Finite element codes and laminated plate theory and virtual work analyses will be used to structurally model the aerodynamic vane and wing tip. Following the basic modeling, a flutter test vane was designed. Each component within the structure was designed to meet the design loads. After the design loads are met, then the deflections will be maximized and the internal structure will be laid out. In addition to the structure, a basic electrical control network will be designed which will be capable of driving a scaled exciter vane. The third and final stage of main investigation involved the fabrication of a 1/4 scale vane. This scaled vane was used to verify kinematics and structural mechanics theories on all-moving actuation. Following assembly, a series of bench tests was conducted to determine frequency response, electrical characteristics, mechanical and kinematic properties. Test results indicate peak-to-peak deflections of 1.1 deg with a corner frequency of just over 130 Hz.Barrett, RonArmstrong Flight Research CenterFLIGHT TESTS; VANES; AERODYNAMIC CONFIGURATIONS; CONTROL SURFACES; FLIGHT CONTROL; ADAPTIVE CONTROL; FLUTTER ANALYSIS; AEROSERVOELASTICITY; DYNAMIC STRUCTURAL ANALYSIS; FREQUENCY RESPONSE; FABRICATION; PITCHING MOMENTS; GROUND TESTS; MACH NUMBER; TRANSONIC FLIGHT; V
Download or read book Applied Vibration Suppression Using Piezoelectric Materials written by Mehrdad R. Kermani and published by Nova Publishers. This book was released on 2008 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this book is to provide insight on the vibration problem in structurally flexible mechanisms, particularly robotic manipulators. The book covers different aspects of flexible structures. It partially includes the fundamental formulations for modelling of a flexible structure actuated with piezoelectric actuators. Mathematical modelling, when possible, as well as experimental techniques for obtaining models of flexible structures are discussed. Additionally, different control techniques adapted for flexible robotic manipulators equipped with piezoelectric actuators and sensors are covered in the book. Depending on the system, linear and non-linear control techniques for stabilising residual vibrations in the system are discussed.
Download or read book Adpative Structures Seventh International Conference written by Barboni Renato and published by CRC Press. This book was released on 1997-03-20 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Piezoelectric Energy Harvesting written by Alper Erturk and published by John Wiley & Sons. This book was released on 2011-04-04 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: The transformation of vibrations into electric energy through the use of piezoelectric devices is an exciting and rapidly developing area of research with a widening range of applications constantly materialising. With Piezoelectric Energy Harvesting, world-leading researchers provide a timely and comprehensive coverage of the electromechanical modelling and applications of piezoelectric energy harvesters. They present principal modelling approaches, synthesizing fundamental material related to mechanical, aerospace, civil, electrical and materials engineering disciplines for vibration-based energy harvesting using piezoelectric transduction. Piezoelectric Energy Harvesting provides the first comprehensive treatment of distributed-parameter electromechanical modelling for piezoelectric energy harvesting with extensive case studies including experimental validations, and is the first book to address modelling of various forms of excitation in piezoelectric energy harvesting, ranging from airflow excitation to moving loads, thus ensuring its relevance to engineers in fields as disparate as aerospace engineering and civil engineering. Coverage includes: Analytical and approximate analytical distributed-parameter electromechanical models with illustrative theoretical case studies as well as extensive experimental validations Several problems of piezoelectric energy harvesting ranging from simple harmonic excitation to random vibrations Details of introducing and modelling piezoelectric coupling for various problems Modelling and exploiting nonlinear dynamics for performance enhancement, supported with experimental verifications Applications ranging from moving load excitation of slender bridges to airflow excitation of aeroelastic sections A review of standard nonlinear energy harvesting circuits with modelling aspects.
Download or read book Smart Structures and Materials written by and published by . This book was released on 1999 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Large Space Structures Systems in the Space Station Era written by and published by . This book was released on 1991 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Progress and New Techniques in Buffet Alleviation written by and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research for twin-tail buffet alleviation is centered on ground tests, wind tunnel tests, and computational fluid dynamics (CFD) analysis. The objective of the research is to improve present technology to obtain a significant reduction in vibration due to buffet. One of the techniques for active control of buffet is the use of smart structures with piezoelectric actuators. The actuators are embedded in the vertical tails in the most advantageous locations to reduce the response of the various structural modes of vibration due to buffet excitation. Ground and wind tunnel tests are necessary to ascertain the piezoelectric actuator's authority at full loads. It is also necessary to evaluate the increase in weight compared with the increase in damping. The results using two different types of piezoelectric actuators are encouraging. In-house wind tunnel tests on a 4.7% scale model of an F-15C aircraft were also conducted to ascertain the effects of tangential blowing and piezoelectric actuators. The tests were performed in the SARL (Subsonic Aerodynamics Research Laboratory) wind tunnel. Tangential blowing had some effect at lower angles of attack. A numerical investigation was conducted simultaneously. This report presents an overview of the buffet research at various organizations, results of the in-house wind tunnel test, and a summary of the computational effort.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1993 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Intelligent Structures written by K.P. Chong and published by CRC Press. This book was released on 2003-10-04 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the International Workshop on Intelligent Structures, Taipei, Taiwan, 23-26 July 1990.
Download or read book Technology for Large Space Systems written by and published by . This book was released on 1989 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aerospace America written by and published by . This book was released on 2002 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt:
