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Overview of the DARPA smart Wing project

JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND structures 2004年第4期15卷 261-267页

作者： Kudva, JN Northrop Grumman Corp El Segundo CA USA

The recently completed DARPA/AFRL/NASA smart Wing program, performed by a team led by Northrop Grumman Corporation (NGC), addressed the development and demonstration of smart materials based concepts to improve the aerodynamic and aeroelastic performance of military aircraft. This paper presents an overview of the program. The program was divided into two phases. Under Phase I (January 1995 to February 1999), the NGC-led team developed adaptive wing structures with integrated actuation mechanisms to replace standard hinged control surfaces and provide variable, optimal aerodynamic shapes for a variety of flight regimes. An important limitation of the Phase I effort, the low bandwidth achievable in Shape Memory Alloy (SMA)-based actuation, was addressed in Phase 2 (January 1997 to November 2001). Under Phase 2, a 30-percent scale full span wind tunnel model of an NGC Uninhabited Combat Air Vehicle (UCAV) design was developed. For the Phase 2 first wind tunnel test, completed in March 2000, SMA-actuated, hingeless, smoothly contoured, flexible leading and trailing edge control surfaces were incorporated on one wing of the model and conventional trailing edge control surfaces actuated using electric motors on the other. This test provided baseline steady-state data at Mach numbers ranging from 0.3 to 0.8. The test also demonstrated the benefits of the smart leading edge control surface to compensate for loss of aileron effectiveness with increasing dynamic pressure. The second test, performed in May 2001, demonstrated a hingeless, smoothly contoured, structurally compliant, trailing edge control surface actuated using piezoelectric motors. Spanwise and chordwise shape control was demonstrated for the smart trailing edge control surface at deflection rates of up to 80degrees/s. Performance improvements in terms of increased rolling and pitching moments and lower control surface deflections were quantified. The work performed under this program has demonstrated the feasi

关键词： smart wing shape memory alloy hingeless control surfaces eccentuator ultrasonic piezoelectric motor

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smart materials and structures VTT Research Program 2000-2002

Smart materials and structures VTT Research Program 2000-200...

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smart materials and structures - VTT research program 2000 - 2002

作者： Vessonen, Ismo VTT Industrial Systems Otakaari 7 B P.O. Box 13022 FIN-02044 VTT Finland

This publication documents the presentation given at the closing seminar of the "smart materials and structures" (ALYMARA) technology program. The publication also reports the main results of the four subprojects of the research program. The aim of the "Active materials" subproject was to gather information on available active materials and to provide support in materials issues for the other three subprojects. A state-of-the-art literature review including functional solid state, polymer and fluid materials was reported. The purpose of the "Precision motion and force" subproject was to develop know-how to apply functional materials in the production of controlled motion and forces. Several prototype structures were designed and implemented: SMA-actuator based "finger", SMA wire-based deforming "bridge", piezo actuator-based gripper including a PC-controller system (1 MSc thesis) and a novel SMA-wire actuator concept, for which a patent has been applied. The "Active durability control" subproject developed know-how to implement machines capable of autonomously controlling fatigue of structures. Several studies (1 MSc thesis) on active control, measurement and signal analysis techniques were reported. Functional virtual prototype with a fuzzy logic durability controller was set up and used to demonstrate the active concepts. In the "Active vibration control" project, a test and demonstration environment was built to study adaptive control systems in active vibration control of rotors. A LicSc thesis was prepared on the basis of the promising results. Semi-active vibration control of vehicle cabins using MR fluid-based dampers and skyhook and fuzzy logic control schemes were studied. Laboratory experiments and computer simulations were used to verify the potentiality of semi-active control.

关键词： Active control Active materials Adaptive systems Adaptronics Durability control Intelligent systems Multifunctional systems Semi-active control smart materials smart structures Vibration control

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Energy optimization of driving amplifiers for smart actuators

Energy optimization of driving amplifiers for smart actuator...

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smart structures and materials 2003 Conference

作者： Zhu, H Song, C Lindner, DK Abdalla, MM Gürdal, Z Virginia Polytech Inst & State Univ CPES Bradley Dept Elect & Comp Engn Blacksburg VA 24061 USA

ISBN: (纸本)0819448540

A high-efficiency driving amplifier with small profile for smart actuators is essential for portable actuator devices. In this paper, a detailed optimized design of half-bridge switching circuit to drive smart actuators is described. The mathematical optimization procedure is applied to the traditional circuit design to make the circuit smaller and more efficient. The objective function presented in this paper is to minimize the total weight of the circuit, including heat sink, inductor and bus capacitor. The calculation of the power dissipation of MOSFET is adopted as a critical step to get the suitable heat sink. The optimization results are presented to demonstrate the effectiveness of this method.

关键词： Field effect transistors Switching Amplifiers Actuators Resistance Optimization (mathematics) Capacitors Electronics smart materials Capacitance

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DARPA/AFRL smart wing phase 2 wind tunnel test results

DARPA/AFRL smart wing phase 2 wind tunnel test results

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smart structures and materials 2002: Industrial and Commercial Applications of smart structures Technologies

作者： Scherer, L.B. Martin, C.A. Sanders, B. West, M. Florance, J. Wieseman, C. Burner, A. Fleming, G. Northrop Grumman Corporation MS 9G21/W6 One Hornet Way El Segundo CA 90245 United States

Northrop Grumman Corporation (NGC) built and twice tested a 30 percent scale wind tunnel model of a proposed uninhabited combat air vehicle (UCAV) under the DARPA/AFRL smart materials and structures Development - smart Wing Phase 2 program to demonstrate the applicability of smart control surfaces on advanced aircraft configurations. The model constructed was a full span, sting mounted model with smart leading and trailing edge control surfaces on the right wing and conventional, hinged trailing edge control surfaces on the left wing. Among the performance benefits that were quantified were increased pitching moment (CM), increased rolling moment (Cl) and improved pressure distribution of the smart wing over the conventional wing. This paper presents an overview of the results from the wind tunnel tests performed at NASA Langley Research Center's (LaRC) Transonic Dynamic Tunnel (TDT) in March 2000 and May 2001. Successful results included: (1) improved aileron effectiveness at high dynamic pressures (Q >250 psf), (2) demonstrated improvements in lateral and longitudinal effectiveness with smooth contoured smart trailing edge over conventional hinged control surfaces, (3) chordwise and spanwise shape control of the smart trailing edge control surface, and (4) smart trailing edge control surface deflection rates over 80 deg/sec.

关键词： Intelligent materials

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Next-generation electroceramic fibers for active control

Next-generation electroceramic fibers for active control

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smart structures and materials 2002 Conference

作者： Bystricky, P Pascucci, MR Strock, HB CernNova Corp Franklin MA 02038 USA

ISBN: (纸本)0819444472

Lead-based PMN-31PT (0.69Pb(Mg1/3Nb2/3)O-3-0.31PbTiO(3)) and lead-free BNBZT (Zr doped Na1/2Bi1/2TiO3-BaTiO3) fibers in the 250-500 micrometer diameter range were produced using CeraNova's proprietary extrusion technology, Various recrystallization approaches were investigated, including seeded solid state conversion and self-seeded texturing, with the goal of obtaining single-crystalline or textured macrocrystalline fibers. Grains in excess of 100 micrometers and exceeding 1 mm. in some cases - with surface and bulk coverage approaching 100%, were obtained in a narrow temperature range and under carefully controlled atmosphere conditions. Large grain growth in BNBZT required the presence of BaSrTiO3 or SrTiO3 seeds and temperatures in the 1150-1200degreesC range. In PMN-31PT, nearly complete recrystallization was observed in unseeded material at relatively low temperature (1000degreesC) and short time (one hour), and improved performance was achieved with a two-step sintering schedule and slightly extended time. While conduction effects have not yet allowed complete assessment of recrystallized BNBZT, PMN-31PT fibers have shown excellent piezoelectric properties with remanent polarization in excess of 3muC/cm(2) and coercive field of 4.5kV/cm. When incorporated into active fiber composites, the latter fibers' performance of 2000 microstrain is superior to average PZT-based production composites. Efforts are under way to induce preferred orientation in the large crystals in order to maximize performance.

关键词： piezoelectric fibers exaggerated grain growth recrystallization texture electro-mechanical characterization

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Enhancing the post-buckling response of a composite panel structure utilising shape memory alloy actuators - a smart structural concept

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COMPOSITE structures 2001年第1期51卷 21-36页

作者： Thompson, SP Loughlan, J Cranfield Univ Struct & Mat Technol Grp Cranfield Coll Aeronaut Cranfield MK43 0AL Beds England

Restoration forces, associated with embedded activated pre-strained shape memory alloy wires, have successfully been employed to enhance the post-buckling behaviour of a laminated panel structure. An extensive experimental and numerical programme has been conducted, of which, results will be presented. The manufacturing methodology of the hybrid SMA/carbon/epoxy panel is outlined. The panel specimen features 0.3 mm diameter shape memory alloy wires embedded and partially consolidated to the host matrix at desired locations. Numerical thermal analysis has been employed to predict the non-uniform temperature profile, attributed to shape memory alloy activation through resistive heating, within the laminate. Structural finite element (FE) analysis has been employed to determine the hybrid panel's adaptive response while under the influence of the uniaxial compressive load in excess of its pseudo-critical buckling value. It is shown that, utilising the control authority generated from the small SMA actuator volume fraction employed, the out-of-plane displacement of the post-buckled laminated panel can be reduced. With the increase in use of composite materials within aerospace platforms, it is envisaged that the hybrid adaptive SMA/laminate configuration will extend the operational performance over conventional materials and structures, particularly when the structure is exposed to an elevated temperature. (C) 2000 Elsevier Science Ltd. All rights reserved.

关键词： post buckling composite panel shape memory alloy adaptive control smart structures

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Vibration isolation/suppression: Research experience for undergraduates in mechatronics and smart structures

Vibration isolation/suppression: Research experience for und...

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smart structures and materials 2001 Conference

作者： Fonda, JW Rao, VS Sana, S Univ Missouri Rolla Intelligent Syst Ctr Dept Elect & Comp Engn Rolla MO USA

ISBN: (纸本)0819440124

This paper provides an account of a student research project conducted under the sponsoring of the National Science Foundation (NSF) program on Research Experience for Undergraduates (REU) in Mechatronics and smart structures in the summer of 2000. The objective of the research is to design and test a stand-alone controller for a vibration isolation/suppression system. The design specification for the control system is to suppress the vibrations induced by the external disturbances by at least five times and hence to achieve vibration isolation. Piezo-electric sensors and actuators are utilized for suppression of unwanted vibrations. Various steps such as modeling of the system, controller design, simulation, closed-loop testing using d-Space rapid prototyping system, and analog control implementation are discussed in the paper. Procedures for data collection, the trade-offs carried out in the design, and analog controller implementation issues are also presented in the paper. The performances of various controllers are compared. The experiences of an undergraduate student are summarized in the conclusion of the paper.

关键词： Device simulation Analog electronics Sensors control systems control systems design Simulink Actuators Vibration isolation Amplifiers smart structures

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smart prosthetics based on magnetorheological fluids

Smart prosthetics based on magnetorheological fluids

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smart structures and materials 2001 Conference

作者： Carlson, JD Matthis, W Toscano, JR Lord Corp Div Mat Cary NC 27511 USA

ISBN: (纸本)0819440183

One of the most exciting new applications for magnetorheological fluid technology is that of real-time controlled dampers for use in advanced prosthetic devices. In such systems a small magnetorheological fluid damper is used to control, in real-time, the motion of an artificial limb based on inputs from a group of sensors. A "smart" prosthetic knee system based on a controllable magnetorheological fluid damper was commercially introduced to the orthopedics and prosthetics market in 2000. The benefit of such an artificial knee is a more natural gait that automatically adapts to changing gait conditions.

关键词： magnetorheological MR fluid prosthetics artificial knee MR fluid damper semi-active control

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Overview of the DARPA/AFRL/NASA smart Wing Phase 2 program

Overview of the DARPA/AFRL/NASA Smart Wing Phase 2 program

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smart structures and materials 2001 Conference

作者： Kudva, JN Sanders, B Pinkerton-Florance, J Garcia, E Northrop Grumman Corporation M/S 9L11/W5 One Hornet Way El Segundo CA 90245 United States

ISBN: (纸本)0819440183

The DARPA/AFRL/NASA smart Wing program, conducted by a team led by Northrop Grumman Corporation (NGC) under the DARPA smart materials and structures initiative, addresses the development of smart technologies and demonstration of relevant concepts to improve the aerodynamic performance of military aircraft. This paper presents an overview of the smart wing program. The program is divided into two phases. Under Phase 1, (1995 - 1999) the NGC team developed adaptive wing structures with integrated actuation mechanisms to replace standard hinged control surfaces and provide variable, optimal aerodynamic shapes for a variety of flight regimes. Two half-span 16% scale wind tunnel models, representative of an advanced military aircraft wing, one with conventional control surfaces and the other with shape memory alloy (SMA) actuated smart control surfaces, were fabricated and tested in the NASA Langley Research Center (LaRC) Transonic Dynamics Tunnel (TDT) during two series of tests, conducted in May 1996 and June 1998, respectively. Details of the Phase I effort are documented in several papers(1,2,3,4). The on-going Phase 2 effort discussed here was started in January 1997 and includes several significant improvements over Phase 1: 1) a much larger, full-span model;2) both leading edge (LE) and trailing edge (TE) smart control surfaces;3) high-band width actuation systems;and 4) wind tunnel tests at transonic Mach numbers and high dynamic pressures (up to 300 psf.) representative of operational flight regimes. Phase 2 includes two wind tunnel tests, both at the NASA LaRC TDT - the first one was completed in March 2000 and the second (and final) test is scheduled for April 2001. The first test demonstrated roll-effectiveness over a wide range of Mach numbers achieved using a combination of hingeless, smoothly contoured, SMA actuated, LE and TE control surfaces. The second test addresses the development and demonstration of high bandwidth actuation. An over-view of the Pha

关键词： smart Wing shape memory alloy hinge-less control surfaces eccentuator ultrasonic piezoelectric motor

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Flexible Tab Assisted control concept - FlexTAC

Flexible Tab Assisted Control concept - FlexTAC

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smart structures and materials 2001 Conference

作者： Nguyen, TD Carpenter, BF Hall, J USN Ctr Surface Warfare Carderock Div Bethesda MD 20817 USA

ISBN: (纸本)0819440183

In late 1997 under ONR and DARPA funding members of the SAMPSON Marine Team (Naval Surface Warfare Center, Lockheed Martin and General Dynamics Electric Boat) began investigating the benefits of the tab assisted control (TAC) concept for underwater control surfaces. Results of water tunnel tests conducted in 1998 indicated that the addition of a small trailing-edge tab, typically 10% of the mean chord of the entire control surface structure, vastly enhances the versatility of the control surface system. Depending on the orientation of the tab with respect to the primary control surface (flap) this tab may be used to significantly modify lift, reduce torque, and increase maneuvering capabilities. In 1999 a plan was established to actuate the tab with Shape Memory Alloy (SMA) actuators as a first step towards development of a continuously compliant or flexible control surface similar to that demonstrated in the DARPA smart Vortex Leveraging Tab (SVLT) program. Testing of a SMA-actuated TAC device occurred late summer 2000. This paper presents a summary of these activities as well as current plans to test and evaluate the FlexTAC (Flexible Tab Assisted control) concept, which replaces the tab with a continuously compliant trailing edge.

关键词： shape memory alloys torque reduction trailing edge tab tab assisted control actuator

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