Prof. George A. Lesieutre Profile

Prof. George A. Lesieutre

Associate Dean for Research at Penn State University

SPIE Involvement:

Author

Publications (31)

Proceedings Article | 20 April 2022 Presentation + Paper

Presentation + Paper

Experimental shape control of cylindrical triplex tensegrity structures

Nate Osikowicz, Kaila Roffman, Puneet Singla, George Lesieutre

Proceedings Volume 12043, 120430G (2022) https://doi.org/10.1117/12.2613117

KEYWORDS: Optical spheres, Visualization, Control systems, Model-based design, Machine vision, Computer vision technology, Systems modeling, Stereoscopic cameras, Visual process modeling, Video, Smart structures, Aerospace engineering, Feedback control, Automatic control

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Proceedings Article | 25 March 2021 Open Access

Open Access

Presentation

Smart structures: a dance between collaboration, creativity, and commerce

George Lesieutre

Proceedings Volume 11586, 1158605 (2021) https://doi.org/10.1117/12.2585070

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Proceedings Article | 4 April 2017 Presentation + Paper

Presentation + Paper

Bimorph-driven synthetic jet actuators optimized for various piezoelectric materials using a low-order model

Tianliang Yu, George Lesieutre, Steven Griffin, Daniel Brzozowski, Aaron Sassoon

Proceedings Volume 10166, 101660B (2017) https://doi.org/10.1117/12.2263359

KEYWORDS: Actuators, Optimization (mathematics), Performance modeling, Systems modeling, Device simulation, Smart materials, Quantum efficiency, Crystals, Instrument modeling, Ferroelectric polymers, Motion models

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Synthetic jet actuators are of interest for potential applications to active flow control and thermal management. Resonant piezoelectric-diaphragm-type configurations are commonly considered. Modeling of such actuators remains a challenge due to complexities associated with both electro-elastic and fluid-structure coupling, as well as potential non-linearities in both. A key metric for synthetic jet performance is the time-averaged jet momentum. Linear lumped-element modeling is an approach that has demonstrated the ability to predict jet momentum in terms of input frequency and voltage; however, it neglects nonlinearity and increasing losses at high amplitude. Full electro-elastic-fluidic finite element modeling makes the most accurate prediction but is computationally expensive for design and optimization purposes. The assumed-modes method provides an energy-based low-order model which captures electro-elastic and acoustic-structure couplings with adequate accuracy. Tri-laminar circular plates under clamped boundary conditions were modeled using the assumed-modes method. Maximization of jet momentum is considered via the maximization of surrogate device metrics: free volume displacement, effective blocking pressure, strain energy, and device coupling coefficient. The driving frequency of the actuator is treated as a constraint in the optimization which nominally matches the fundamental acoustic natural frequency of the cylindrical cavity. Device configurations were obtained for various polycrystalline and single crystal piezoelectric materials, driven at 10% of their coercive fields in the model. The optimal configurations approximate a simply-supported circular plate with complete piezo coverage. The relative merits of individual materials were also discerned from the optimization results. The low mechanical loss factor of PZT8 enables high output at resonance, while high loss factor and low stiffness limit the utility of PVDF in this application. Due to a combination of lower loss factor and higher coupling, single crystal materials modestly outperform PZT5A.

Proceedings Article | 27 April 2011 Paper

Paper

Design, fabrication, and testing of contact-aided compliant cellular mechanisms with curved walls

Samantha Cirone, Gregory Hayes, Brian Babcox, Mary Frecker, James Adair, George Lesieutre

Proceedings Volume 7977, 79771F (2011) https://doi.org/10.1117/12.880529

KEYWORDS: Finite element methods, Manufacturing, Ceramics, Skin, Computer aided design, Microfabrication, Fabrication, MATLAB, Zirconium dioxide, Particles

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Proceedings Article | 27 April 2011 Paper

Paper

Performance of piezoelectric-based damping techniques for structures with changing excitation frequencies

Jeffrey Kauffman, George Lesieutre

Proceedings Volume 7977, 79770D (2011) https://doi.org/10.1117/12.880515

KEYWORDS: Switching, Switches, Resistance, Solids, Inductance, Analytical research, Motion models, Vibration control, Circuit switching, Vibrometry

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Proceedings Article | 3 April 2008 Paper

Paper

Contact-aided compliant mechanisms for morphing aircraft skin

Vipul Mehta, Mary Frecker, George Lesieutre

Proceedings Volume 6926, 69260C (2008) https://doi.org/10.1117/12.773599

KEYWORDS: Skin, Aerodynamics, Stereolithography, Nomenclature, 3D modeling, Aerospace engineering, Unmanned aerial vehicles, Shape memory polymers, Composites, Einsteinium

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Proceedings Article | 18 April 2007 Paper

Paper

Tendon actuated cellular mechanisms for morphing aircraft wing

Smita Bharti, Mary Frecker, George Lesieutre, Jamie Browne

Proceedings Volume 6523, 652307 (2007) https://doi.org/10.1117/12.715855

KEYWORDS: Prototyping, Diamond, Actuators, Aluminum, Aerodynamics, Finite element methods, Control systems, Skin, Kinematics, Manufacturing

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Proceedings Article | 27 March 2006 Paper

Paper

Optimal structural design of a morphing aircraft wing using parallel non-dominated sorting genetic algorithm II (NSGA II)

Smita Bharti, Mary Frecker, George Lesieutre

Proceedings Volume 6166, 616602 (2006) https://doi.org/10.1117/12.659088

KEYWORDS: Finite element methods, Genetic algorithms, Actuators, Aerodynamics, Chemical elements, Structural design, Optimization (mathematics), Binary data, Francium, Error analysis

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Proceedings Article | 19 May 2005 Paper

Paper

Optimal design of tendon-actuated morphing structures: nonlinear analysis and parallel algorithm

Smita Bharti, Mary Frecker, George Lesieutre, Deepak Ramrakhyani

Proceedings Volume 5757, (2005) https://doi.org/10.1117/12.601088

KEYWORDS: Genetic algorithms, Error analysis, Finite element methods, Actuators, Chemical elements, Aerodynamics, Algorithm development, Genetics, Aerospace engineering, Optimization (mathematics)

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Proceedings Article | 16 May 2005 Paper

Paper

Averaging analysis of state-switched piezoelectric structural systems

A. Kurdila, G. Lesieutre, X. Zhang, C. Prazenica, C. Niezrecki

Proceedings Volume 5760, (2005) https://doi.org/10.1117/12.605488

KEYWORDS: Calcium, Switching, Switches, Cesium, Capacitance, Actuators, Power supplies, Circuit switching, Control systems, Signal attenuation

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Proceedings Article | 29 July 2004 Paper

Paper

Development of a design curve for particle impact dampers

Michael Yang, George Lesieutre, Stephen Hambric, Gary Koopmann

Proceedings Volume 5386, (2004) https://doi.org/10.1117/12.540019

KEYWORDS: Particles, Beam shaping, Calibration, Sensors, Electromagnetism, Video, Aluminum, Liquids, Velocity measurements, Signal analyzers

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Proceedings Article | 29 July 2004 Paper

Paper

Numerical investigation of particle impact dampers

Sanjiv Ramachandran, George Lesieutre

Proceedings Volume 5386, (2004) https://doi.org/10.1117/12.540182

KEYWORDS: Particles, Analytical research, Oscillators, Solids, Motion models, Mathematical modeling, Numerical simulations, Data modeling, Aerospace engineering, Complex systems

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Particle impact dampers (PIDs) have been shown to be effective in vibration damping. However, our understanding of such dampers is still limited, based on the theoretical models existing today. Although considerable research has been carried out in the generic field of 'impact oscillators,' much of it uses sophisticated mathematical tools and is somewhat inaccessible to the practicing engineer. Predicting the performance of the PID is an important problem, which needs to be investigated more thoroughly. This research seeks to understand the dynamics of a PID as well as what parameters govern its behavior. The system investigated is a particle impact damper with a ceiling, under the influence of gravity. The base is harmonically excited in the vertical direction. A discrete event approach is used, wherein the variables at one 'event' (or impact) uniquely dictate the variables at the next 'event', leading to a two-dimensional difference map. This map is then solved using a numerical continuation procedure. Periodic impact motions and 'irregular' motions are observed. The effects of various parameters such as the gap clearance, coefficient of restitution and the base acceleration are analyzed. The dependence of the loss factor on these parameters is also studied. The loss factor results indicate a peak for certain combinations of parameters. These combinations of parameters correspond to a region in parameter space where two-impact-per-cycle motions are observed over a wide range of non-dimensional base accelerations. The value of the non-dimensional acceleration at which the onset of two-impact-per-cycle solutions occurs depends on the non-dimensional gap clearance and the coefficient of restitution. The range of non-dimensional gap clearances over which two-impact-per-cycle solutions are observed increases as the coefficient of restitution increases. In the regime of two-impact-per-cycle solutions, the value of non-dimensional base acceleration corresponding to onset of these solutions initially decreases and then increases with increasing the non-dimensional gap clearance. As the two-impact-per-cycle solutions are associated with high loss factors that are relatively insensitive to changing conditions, they are of great interest to the designer.

Proceedings Article | 26 July 2004 Paper

Paper

Active and passive material optimization in a tendon-actuated morphing aircraft structure

Smita Bharti, Mary Frecker, George Lesieutre, Deepak Ramrakhyani

Proceedings Volume 5390, (2004) https://doi.org/10.1117/12.540198

KEYWORDS: Aerodynamics, Chemical elements, Genetic algorithms, Aircraft structures, Actuators, Finite element methods, Aerospace engineering, Algorithm development, Shape memory alloys, Skin

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Proceedings Article | 26 July 2004 Paper

Paper

Design of a single-crystal piezoceramic-driven synthetic jet actuator

Razvan Rusovici, George Lesieutre

Proceedings Volume 5390, (2004) https://doi.org/10.1117/12.539576

KEYWORDS: Actuators, Control systems, Silicon, Crystals, Finite element methods, Combustion, Aerodynamics, Pollution, Ferroelectric materials, Microfluidics

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Proceedings Article | 31 July 2003 Paper

Paper

Investigations of viscoelastic structure behavior using a three-dimensional anelastic displacement field finite element

Razvan Rusovici, George Lesieutre

Proceedings Volume 5052, (2003) https://doi.org/10.1117/12.483963

KEYWORDS: Solids, Motion models, Wave propagation, 3D modeling, Aerospace engineering, Matrices, Electronics, Vibration isolation, Structural dynamics, Thermodynamics

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Proceedings Article | 15 July 2002 Paper

Paper

Design of single-crystal vibration absorbers

Razvan Rusovici, Jeffrey Dosch, George Lesieutre

Proceedings Volume 4701, (2002) https://doi.org/10.1117/12.474687

KEYWORDS: Crystals, Electromechanical design, Finite element methods, Actuators, Control systems, Capacitors, Transducers, Aluminum, Analytical research, Resistors

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Proceedings Article | 16 August 2001 Paper

Paper

Modeling and simulation of a resonant bimorph actuator drive

Eric Mockensturm, Jeremy Frank, Gary Koopmann, George Lesieutre

Proceedings Volume 4327, (2001) https://doi.org/10.1117/12.436560

KEYWORDS: Actuators, Mathematical modeling, Prototyping, Ferroelectric materials, Motion models, Chemical elements, Data modeling, Modeling and simulation, Performance modeling, Oscillators

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Proceedings Article | 2 July 2001 Paper

Paper

Development and validation of anelastic-displacement-fields-based dynamic finite elements

Razvan Rusovici, Daniel Inman, George Lesieutre

Proceedings Volume 4331, (2001) https://doi.org/10.1117/12.432715

KEYWORDS: Wave propagation, Finite element methods, Motion models, Matrices, Neon, 3D modeling, Signal attenuation, Thermodynamics, Particles, Data modeling

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Proceedings Article | 14 June 2001 Paper

Paper

Resonant bimorph-driven high-torque piezoelectric rotary motor

George Lesieutre, Gary Koopmann, Eric Mockensturm, Jeremy Frank, Weicheng Chen

Proceedings Volume 4332, (2001) https://doi.org/10.1117/12.429675

KEYWORDS: Actuators, Electronics, Diodes, Smart structures, Ceramics, Ferroelectric materials, Position sensors, Control systems, Lead, Magnetism

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Proceedings Article | 22 June 2000 Paper

Paper

Design and performance of a resonant roller wedge actuator

Jeremy Frank, Gary Koopmann, Weicheng Chen, Eric Mockensturm, George Lesieutre

Proceedings Volume 3985, (2000) https://doi.org/10.1117/12.388824

KEYWORDS: Actuators, Ferroelectric materials, Prototyping, Magnetism, Acoustics, Amplifiers, Laser induced plasma spectroscopy, Interfaces, Ceramics, Smart structures

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Proceedings Article | 22 June 2000 Paper

Paper

Design and realization of variable-frequency flexural piezoceramic transducers

Julien Bernard, George Lesieutre

Proceedings Volume 3985, (2000) https://doi.org/10.1117/12.388878

KEYWORDS: Transducers, Polarization, Switches, Acoustics, Electrodes, Finite element methods, Coating, Projection systems, Receivers, Chemical elements

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Being high Q devices, low frequency underwater transducers often lack bandwidth. Variable resonance frequency transducers offer the double advantage of increased effective bandwidth and maximum response at all frequencies within the bandwidth. This paper presents and evaluates a technique to vary the first resonance frequency of some widely used underwater acoustics transducers: flexural piezoceramic bars and disks. DC bias electric fields are added to the AC driving field and used to generate in-plane tensile or compressive loads. These loads modify the flexural rigidity of the transducer, which in turn affects its resonance frequencies. Theoretical investigations show that the frequency shift per DC field is linked to the ratio of the in-plane blocked force to the critical buckling load of the transducer. This ratio depends on the type of piezoceramic material and coupling, the boundary conditions, the length to thickness ratio of the transducer, and the piezoceramic thickness and coverage. Calculations show that both significant frequency shifts per DC field and acceptable device coupling coefficients may be achievable in practice. A flexural bar transducer using k₃₁ coupling was built and tested. The experimental frequency shift per DC field and coupling coefficient were lower than predicted. Measurements show the existence of a polarization switch due to a combined compressive stress and negative field effect at -400 V/mm DC field. This polarization switch limits the range of useful negative DC fields, therefore limiting the total frequency shift, and also results in a permanent reduction of the polarization level, therefore reducing the amount of frequency shift per DC field. In the case of k₃₁ coupling, one must determine the safe stress and field region for the material and try to operate within the corresponding DC field range. In the case of k₃₃ coupling, compressive stresses and negative fields do not occur simultaneously, and the available DC field range should be much higher.

Proceedings Article | 9 June 1999 Paper

Paper

Design and performance of a high-force piezoelectric inchworm motor

Jeremy Frank, Gary Koopmann, Weicheng Chen, George Lesieutre

Proceedings Volume 3668, (1999) https://doi.org/10.1117/12.350747

KEYWORDS: Actuators, Tolerancing, Titanium, Prototyping, Acoustics, LabVIEW, Signal generators, Analog electronics, Transducers, Velocity measurements

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Proceedings Article | 27 July 1998 Paper

Paper

Design, modeling, and performance of a high-force piezoelectric inchworm motor

Timothy Galante, Jeremy Frank, Julien Bernard, Weicheng Chen, George Lesieutre, Gary Koopmann

Proceedings Volume 3329, (1998) https://doi.org/10.1117/12.316945

KEYWORDS: Actuators, Phase shifts, Instrument modeling, Motion measurement, Manufacturing, Performance modeling, LabVIEW, Signal generators, Acoustics, Control systems

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Proceedings Article | 16 June 1998 Paper

Paper

Actively tuned solid state piezoelectric vibration absorber

Christopher Davis, George Lesieutre

Proceedings Volume 3327, (1998) https://doi.org/10.1117/12.310681

KEYWORDS: Capacitance, Actuators, Capacitors, Control systems, Relays, Sensors, Signal attenuation, Switches, Prototyping, Solid state physics

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A tunable solid state piezoelectric vibration absorber and an active tuning method were developed and demonstrated. A passive vibration absorber generally acts to minimize structural vibration at a specific frequency associated with either a tonal disturbance or the response of a lightly damped structural vibratos mode. Because this frequency is rarely stationary in real applications, damping is usually added to ensure some level of effectiveness over a range of frequencies. Maximum response reductions, however, are achieved only if the absorber is lightly damped and accurately tuned to the frequency of concern. Thus, an actively-tuned vibration absorber should perform better than a passive one and, furthermore, could be made lighter. In its simplest form, a vibration absorber consists of a spring-mass combination. A key feature of the tunable vibration absorber described herein is the use of piezoelectric ceramic elements as part of the device stiffness. The effective stiffnesses of these elements was adjusted electrically, using a passive capacitive shunt circuit, to tune the resonance frequency of the device. The tuning range of the absorber is thus bounded by its short- circuit and open-circuit resonance frequencies. An alternative tuning approach might employ resistive shunting, but this would introduce undesirable damping. Another feature of the device is the ability to use the piezoelectric elements as sensors. A control scheme was developed to estimate the desired tuning frequency from the sensor signals, to determine the appropriate shunt capacitance, and then to provide it. The shunt circuit itself was implemented in ten discrete steps over the tuning range, using a relay-driven parallel capacitor ladder circuit. Experimental results showed a maximum 20 dB, and a 10 dB average improvement in vibration reduction across the tuning range, as compared to a pure passive absorber tuned to the center frequency, with additional benefit extending beyond the tuning range.

Proceedings Article | 6 June 1997 Paper

Paper

Can a coupling coefficient of a piezoelectric device be higher than those of its active material?

George Lesieutre, Christopher Davis

Proceedings Volume 3041, (1997) https://doi.org/10.1117/12.275653

KEYWORDS: Aluminum, Ferroelectric materials, Capacitance, Transducers, Actuators, Ceramics, Resistors, Sensors, Dielectrics, Lead

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Proceedings Article | 9 May 1997 Paper

Paper

Finite element for beams having segmented active constrained layers with frequency-dependent viscoelastic material properties

George Lesieutre, Usik Lee

Proceedings Volume 3045, (1997) https://doi.org/10.1117/12.274210

KEYWORDS: Finite element methods, Control systems, Chemical elements, Matrices, Sensors, Motion models, 3D modeling, Modal analysis, Mathematical modeling, Systems modeling

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Proceedings Article | 9 May 1997 Paper

Paper

Tunable electrically shunted piezoceramic vibration absorber

Christopher Davis, George Lesieutre, Jeffrey Dosch

Proceedings Volume 3045, (1997) https://doi.org/10.1117/12.274188

KEYWORDS: Actuators, Capacitance, Acoustics, Capacitors, Resistance, Aircraft structures, Active vibration control, Signal attenuation, Resistors, Aluminum

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Proceedings Article | 1 May 1996 Paper

Paper

Embeddable induced strain actuator using a framed 3-3 piezoceramic stack: modeling and characterization

Gary Koopmann, George Lesieutre, Brian Dershem, Weicheng Chen, Shoko Yoshikawa

Proceedings Volume 2721, (1996) https://doi.org/10.1117/12.239136

KEYWORDS: Actuators, Calibration, Ferroelectric materials, Composites, Transducers, Mechanical efficiency, Ceramics, Electrodes, Multilayers, Titanium

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Proceedings Article | 1 May 1996 Paper

Paper

Heat generation of a piezoceramic induced-strain actuator embedded in a glass/epoxy composite panel

George Lesieutre, Lei Fang, Gary Koopmann, Suresh Pai, Shoko Yoshikawa

Proceedings Volume 2717, (1996) https://doi.org/10.1117/12.239030

KEYWORDS: Actuators, Composites, Temperature metrology, Dielectrics, Ceramics, Convection, Reliability, Interfaces, Smart structures, Titanium

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Proceedings Article | 12 May 1995 Paper

Paper

Inertial piezoceramic actuators for smart structures

Craig Asckler, George Lesieutre, Gary Koopmann, Christopher Davis

Proceedings Volume 2447, (1995) https://doi.org/10.1117/12.209333

KEYWORDS: Actuators, Instrument modeling, Smart structures, Electromechanical design, Performance modeling, Transducers, Solids, Reliability, Vibration control, Manufacturing

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Proceedings Article | 8 May 1995 Paper

Paper

Design of an embedded piezoceramic actuator for active control applications

Gary Koopmann, George Lesieutre, Shoko Yoshikawa, Weicheng Chen, John Fahnline, Suresh Pai, Brian Dershem

Proceedings Volume 2443, (1995) https://doi.org/10.1117/12.208307

KEYWORDS: Actuators, Ceramics, Ferroelectric materials, Composites, Lead, Dielectrics, Electrodes, Polymers, Finite element methods, Amplifiers

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Showing 5 of 31 publications

Conference Committee Involvement (10)

Active and Passive Smart Structures and Integrated Systems II

10 March 2008 | San Diego, California, United States

Active and Passive Smart Structures and Integrated Systems

19 March 2007 | San Diego, California, United States

Smart Structures and Integrated Systems

27 February 2006 | San Diego, California, United States

Damping and Isolation

27 February 2006 | San Diego, California, United States

Smart Structures and Integrated Systems

7 March 2005 | San Diego, California, United States

Showing 5 of 10 Conference Committees

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