Ground and Flight Test Structural Excitation Using Piezoelectric Actuators


Book Description

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.




Ground and Flight Test Structural Excitation Using Piezoelectric Actuators


Book Description

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




Proceedings of the Third World Conference on Structural Control


Book Description

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.