Prof. Baillieil is engaged in wide spectrum of research activity involving robotics, controls, and mechatronics.

Readers are encouraged to visit the following sites for a suite of program and project descriptions:

Center for Human and Robot Decision Dynamics

The Intelligent Mechatronics Laboratory

The Personal Website for John Bailliel

Faculty:
Prof. John Baillieul

Back to top

Hybrid Asymptotic-Numerical Methods in Scattering

Hybrid asymptotic-numerical methods for scattering have the potential to combine the flexibility of traditional numerical methods with the efficiency of high-frequency asymptotic methods. The approach taken here is to replace the original boundary value problem (b.v.p.) with an asymptotically equivalent boundary value problem (a.b.v.p.) which can be discretized and solved readily.

The definition of a.b.v.p. depends on a preliminary analysis using the geometrical theory of diffraction. The problem domain Omega is then divided into two (not necessarily connected) subdomains Omega_A and Omega_D, where Omega_D contains all the regions of diffraction and Omega_A contains those portions of the domain where the ray ansatz is valid. The rays in Omega_A are then used as basis functions with unknown amplitudes in a variational statement of the b.v.p., thus resulting in the a.b.v.p. The resulting variational statement over the domain Omega_D=Omega/Omega_A can be discretized and efficiently solved by classical numerical methods. Continuity of the field between Omega_A and Omega_D is enforced through this specially derived variational statement.

Faculty:
Prof. Paul Barbone

Related Projects:
Structural Design for Shock Mitigation

Back to top

MEMS Mirrors

A new class of micro-electro-mechanical deformable mirrors (MEMS-DMs) is being developed at Boston University's Precision Engineering Research Laboratory. These devices are capable of correcting time-varying aberrations in imaging or beam forming applications. Each mirror is composed of a flexible silicon membrane supported by an underlying array of electrostatic parallel plate actuators. Real-time correction of optical aberrations has been demonstrated with these mirrors in a closed-loop feedback control system. Novel processing techniques have been developed to fabricate, planarize, and control the MEMS-DM devices. The advantages of MEMS-DMs in cost, compactness, power consumption, and speed in comparison to existing DMs should, over the next several years, extend the range of optical imaging and beamforming applications that can benefit from adaptive compensation.

Faculty:
Prof. Thomas Bifano, Prof. David Castañon (ECE), Prof. Mark Horenstein (ECE)

Students:
Julie Perrault

Back to top

Refractive and clear air turbulence in the upper troposphere and lower stratosphere

Turbulence in the Upper Troposphere and Lower Stratosphere (UTLS) can adversely impact performance of a range of aerospace systems; optical Turbulence (OpT) from fluctuations in temperature and humidity can disrupt communications, radar, and high energy laser systems and Clear Air Turbulence (CAT) can lead to aircraft upset. The main thrust of this project is characterization and analysis of turbulent layers in the stably stratified regions of UTLS, using high resolution turbulence data collected from Air Force sponsored aircraft measurement campaigns.  The research includes the study of layer formation and evolution, analysis of statistical descriptors of the flow, such as structure functions, and the identification and characterization of coherent structures.  The work also involves collaboration with Direct Numerical Simulation (DNS) researchers, to provide insights that can’t be gleaned from measurements or DNS alone, and to aid in validation of the simulations.  This work is funded by AFRL.

Professors:      D. Wroblewski
Collaboraters:  O. Cote (AFRL), J. Hacker (Flinders University, Australia), R. Dobosy (NOAA), J. Werne (NWRA/CORA).

Back to top

CD Mastering

In North America, more than a billion optical discs (CD and DVD) are sold each year. Discs are made by injection molding using a master stamper. The industry faces demand for increased production speed, increased yield, and decreased hazardous waste generation. At BU-PERL, we have developed a patented new process for DVD stamper manufacturing. This new process replaces several difficult and failure-prone process steps with a radically improved, simpler alternative. The new process entails precision ion etching of DVD features directly onto a nickel master stamper, without electroplating. By eliminating the processes that are responsible for most of the toxic waste by-products (e.g. heavy metals, acids, and solvents) generated during stamper manufacturing, the new process is significantly cleaner. The new process also reduces fabrication time for a DVD stamper by more than half. By industry standards this is a revolutionary change in optical disk mastering technology. The process can be used for all DVD types, and requires almost no retooling of the DVD manufacturing line. A feasibility study funded by the Boston University Center for Photonics Research and the US Department of Energy was recently completed. In partnership with Prism Corporation, we are proceeding with development of a production-scale manufacturing system and optimization of the new process. (Commercial info: PrismCorp@aol.com)

Faculty:
Prof. Thomas Bifano

Students:
Mirela Bancu

Back to top

Targeted Ultrasound Contrast Agents for Drug Delivery

This is project is a collaboration with Prof. Joyce Wong of the Department of Biomedical Engineering (BME) at BU.  Prof. Wong is developing molecules that target and bind to diseased tissue.   One barrier to her work is finding appropriate contrast agents that these molecules can be attached to so that the diseased tissue can be imaged.  One candidate is the ultrasound contrast agent, which typically consists of a gas microbubble, 1 to 5 µm in diameter, encapsulated with a thin shell.  We are investigating the use of polymer-shelled contrast agents.  The ultrasound imaging systems and scanning acoustic microscope are used to characterize the properties of the microbubbles developed in the Wong Lab.  This work is funded by the National Institutes of Health and the NSF Centre for Subsurface Sensing and Imaging Systems.

Faculty:          R.O. Cleveland,  J. Y. Wong (BME-BU).
Recent Students:          W. Duncanson (PhD)

Back to top

Acoustics in Bubbly Media

Increased understanding of sound's interaction with the real ocean environment is sought via theoretical and experimental pursuits. Specifically, we seek to further understand the effects of bubbles and bubble clouds on sound propagation, with practical applications in shallow-water sonar and minehunting. Bubbles and bubble clouds are generated in the near surface layer of the ocean due to both natural processes and human activities. Common examples are breaking waves, biologics and ship wakes.

Faculty:
Ron Roy, William Carey

Students:
Preston Wilson, Ryan McCormick

Back to top

Snapshots from a 3D computer simulation of the passage of a shock wave through a kidney stone.

Lithotripsy

Shock Wave Lithotripsy (SWL) is a non-invasive medical technique for treating kidney stones.  Shock waves generated outside the body are focused onto the kidney stones resulting in fragmentation into pieces small enough to be passed naturally.   The goal of the research is to understand the process by which the shock waves fragment the stones and to understand the mechanisms by which shock waves can damage the surrounding soft tissue.  This work is carried out in collaboration with colleagues at Indiana University Medical School, University of Washington at Seattle, Caltech, University of Illinois and the BU Medical School.   This work is primarily funded by the National Institutes of Health and has also been supported by the Whitaker Foundation.

Faculty:  R.O. Cleveland
Recent Students: P Chitnis (PhD 2006), H. Luo (PhD), J. Kracht (PhD)

To read more about this project visit the Lithotripsy Research page on the Physical Acoustics Laboratory web site.

Back to top

Quantatative Ultrasound Imaging

The goal of this project is to employ tomographic inversion of ultrasound data to detect HIFU lesions.  In general tomographic reconstruction of ultrasound data in the body is not practical because the limited acoustic windows into the body normally mean only limited-view backscatter data is available.  The resulting inversion problem is therefore poorly posed.  In the case of HIFU however the individual lesions are approximately ellipsoidal in shape and the approximate position and size is known a priori.  Second, the process of necrosis results in change in sound speed and attenuation inside the lesion from their nominal values. Therefore the lesion can be described using shape-based methods where it is necessary to estimate only a small number of parameters to describe the geometry of the lesion rather than determine all the acoustics properties over all space.  This makes the inversion problem tractable even with the limited view backscatter data of an ultrasound probe.

Faculty:  R.O. Cleveland,  E.L. Miller (ECE-Tufts), B. Durning (BU/ECE-Tufts).

Recent Students:    B. Ulker-Karbeyaz (Northeasten PhD 2005), A. Draudt (PhD), E. Guven (Northeastern PhD)

Back to top

Targeted Ultrasound Contrast Agents for Drug Delivery

This is project is a collaboration with Prof. Joyce Wong of the Department of Biomedical Engineering (BME) at BU.  Prof. Wong is developing molecules that target and bind to diseased tissue.   One barrier to her work is finding appropriate contrast agents that these molecules can be attached to so that the diseased tissue can be imaged.  One candidate is the ultrasound contrast agent, which typically consists of a gas microbubble, 1 to 5 µm in diameter, encapsulated with a thin shell.  We are investigating the use of polymer-shelled contrast agents.  The ultrasound imaging systems and scanning acoustic microscope are used to characterize the properties of the microbubbles developed in the Wong Lab.  This work is funded by the National Institutes of Health and the NSF Centre for Subsurface Sensing and Imaging Systems.

Faculty:          R.O. Cleveland,  J. Y. Wong (BME-BU).
Recent Students:          W. Duncanson (PhD)

Back to top

Optimal Port Placement for Minimally Invasive Surgery

A computer-based algorithm has been developed which uses preoperative images to provide a surgeon with a list of feasible port triplets ranked according to tool dexterity and endoscopic view quality at each surgical site involved in a procedure. A computer simulation allows the surgeon to select from among the proposed port locations. The procedure selected for the development of the system consists of a coronary artery bypass graft (CABG). In this procedure, the interior mammary artery (IMA) is mobilized from the interior chest wall, and one end is attached to the coronary arteries to provide a new blood supply for the heart. Approximately 10-20 cm is dissected free, using blunt dissection and a harmonic scalpel or electrocautery. At present, the port placement system is being evaluated in clinical trials.

More details.

Faculty:
Prof. Pierre Dupont

Back to top

Modeling by Manipulation

At present, teleoperation is the only way that robots can perform sophisticated manipulation tasks in unstructured environments. In this control mode, the human operator performs all required sensing and planning, and generates all motion commands based on feedback from the remote environment. In practical teleoperation systems (e.g. undersea operations, tele-surgery, etc ), the sensory feedback is often limited to video images without force feedback, which greatly restricts dexterity and productivity. We have been working to alleviate this situation by using information from the remote robot arm's sensors to assist in teleoperated manipulation tasks. We have derived algorithms that identify first order geometric properties such as dimensions and orientations.

More details.

Faculty:
Prof. Pierre Dupon

Back to top

Mechanical Realization

Before building main structures such as ship hulls and airplane fuselages on which equipments can survive, scaled mechanical models are often used to test structural design concepts. In this research, we want to study the design methods for mechanical emulators which preserve the driving-point behaviors of the active machineries (such as turbine generators, motors) and the passive equipments which are usually the most dynamically complex components in the dynamical system. For the passive equipment emulators, the following approaches will be used. First, by using model reduction methods, reduced-order models will be achieved based on modal analysis data. Second, the reduced-order models will be realized by different approaches such as optimization procedure, electrical network synthesis and state space techniques. For active mechanical emulators, shakers will be used to emulate the active components in the machineries.

Faculty:
Prof. Pierre Dupont

Back to top

Multichannel Vibrotactile Display

Augmenting perception in man-machine systems consists of two parts. First, machine sensor data must be interpreted in a way appropriate to the task. Second, the task-specific information must be communicated to the operator in a format that addresses the limitations of human sensory information processing. For example, during teleoperated surgery, vocal communication between non-operator team members can interfere with an auditory display. Similarly, overlaying visual displays with an endoscope view during surgery can be costly and non-intuitive due to scene complexity and the wide range of viewpoints encountered. Within this context, a multichannel vibrotactile device was designed, developed and tested for sensory substitution during teleoperation.

More details.

Faculty:
Prof. Pierre Dupont

Back to top

Friction Modeling and Compensation

The nonlinear and dynamic behavior of friction is often a significant impediment to precision motion control in systems as diverse as disk drives and machine tools. There are three goals of this research. The first is to develop physically-based friction models for control and damping applications. The second is to derive techniques for on-line identification of friction parameters. The third goal is to derive control techniques which are robust with respect to variations in frictional dynamics.

Faculty:
Prof. Pierre Dupont

Publications

Back to top

Use of Conventional Fluid Dynamics to Predict Sound Generated by Complex Flows

The research will enable the acoustic portion of a complicated flow field to be identified as a subsequent step in a CFD calculation even if the original calculation is only valid for incompressible flow. This method is called the acoustic projection method. The fundamental idea is not new in the sense that some researchers currently use methods based on Lighthill's acoustic analogy, take fluid dynamic results, and from them calculate, the sound radiated by the flow. However, the method used in this research allows the acoustics to be identified within the region containing the complex flow as opposed to only outside this region. Also, the outcome of this research will be a computational supplement to CFD codes which can be easily used and understood by those who are not experts in acoustics.

Faculty:
Prof. Sheryl Grace; Prof. Allan Pierce; Christophe Bailly (Ecole Central De Lyon, Lyon France)

Publications

Back to top

Panel Method Based Prediction of Sound Generated by a Multi-Element High-Lift Wing Section

The research provides a prediction tool for airframe noise generated by high-lift wing configurations. The goal of the project is to develop a design tool which will capture the important acoustic production mechanisms without fully modeling the viscous nonlinear fluid dynamics existing near a high-lift wing. The mechanisms which will be modeled include the oscillation of the vortex core which forms in the cove under the slat and the main airfoil element, the forced unsteady flow through the slat gap which interacts with the slat tracks, the upstream airfoil element wakes which convect past the downstream airfoil elements and induce fluctuating surface forces, and the vorticity created at side edges.

The prediction tool will consist of an unsteady panel method for calculating the unsteady aerodynamic forces coupled to an acoustic propagation model. The method will enable simultaneous aerodynamic and acoustic analysis of high-lift systems to be completed in a short time on a modern work station. Moreover, external forces such as ground effect can be included quite simply into the model.

Faculty:
Prof. Sheryl Grace; Prof. Luigi Morino (Univ. of Rome)

Students:
Trevor Wood

Back to top

Rayleigh Conductivity

Use of the Rayleigh conductivity parameter for analyzing low mach number high Reynolds number flow past wall openings and wall apertures. The analysis is used to determine frequency ranges in which unsteady disturbances will be amplified or absorbed by the shear layer which forms in the mouth of the wall opening.

Faculty:
Prof. Sheryl Grace; Prof. Michael Howe

Students:
Trevor Wood, Kelly Horan (former)

Publications

Back to top

The Aeromechanical Effect of Vane Clocking in Turbines

This research will evaluate and improve existing methods for predicting multi-stage effects in turbines. The evaluation will be based on comparisons of the computational predictions and previously obtained experimental data. Until this time, most multi-stage studies focused on the optimization of efficiency. In this research, the emphasis will be on the prediction of the unsteady blade loading. Once a valid unsteady aerodynamic prediction tool is identified, it will give General Electric Aircraft Engineering a method for determining the indexing which will simultaneously provide best efficiency and reduction of blade fatigue.

Faculty:
Prof. Sheryl Grace

Students:
Ruby Zenon

Back to top

Inverse Problem in Aeroacoustics & Unsteady Aerodynamics

Traditionally, in studying aerodynamically generated sound, one first identifies and quantifies the sources of sound and then calculates the scattered sound. This direct approach has been used to study sound generated by incident acoustic and vortical disturbances or turbulence interacting with a body as well as sound from jets.

In this research, we developed an inverse approach for the aeroacoustic problem of a streamlined body in a subsonic mean flow. The radiated sound is generated as a result of either the oscillatory motion of the body or the interaction of incident acoustic or vortical waves with the body. Our development of the inverse approach mirrors the development of the direct problem. We consider the case of a 2-D flat-plate airfoil and a 3-D rectangular wing in unsteady subsonic flow. We have demonstrated the feasibility of performing the aeroacoustic inversion for both of these cases.

Faculty:
Prof. Sheryl Grace

Students:
Trevor Wood

Publications

Back to top

Rheology of Foam

Foams are extremely important in a variety of industrial applications. They are widely used in firefighting applications, including the Fire Suppression Systems aboard the Space Shuttle and Spacelab module. The petroleum industry utilizes foams in flow applications such as enhanced oil recovery and as drilling fluids. They are used in various industries as trapping, transport, and separation agents. Arguably the most important quality of a foam in many of these industrial processes is its response to imposed strain, or its rheological behavior. There exists almost no experimental data on the rheological properties of real 3D foams, even though such knowledge would likely enhance the efficacy of current applications and suggest other unique applications. The lack of 3D data is due in large part to the earth-based requirements for contact containment, and to the fact that gravity-induced drainage quickly destroy all but the "driest" foams, those with a very high gas volume fraction. Our goal in this project is to develop and refine a unique acoustic levitation method to provide non-contact control and manipulation of foam samples. The development of this technique, together with experimentation in Og, will provide the ability to carry out a set of benchmark experiments which will allow determination of a foam's yield stress, bulk shear, and dilatational moduli and viscosities as a continuous function of gas volume (or 'void') fraction from the dry limit through the order-disorder phase transition to the wet limit of a bubbly liquid. In addition to providing the first measurements of such quantities as functions of void fraction to compare with theory, the knowledge gained will have practical application to the myriad of actual uses of foams on the earth, and to space-based systems. By closely interfacing these data with emerging theoretical results from other groups (including our own proposed work) the fundamental understanding of foam rheology will be advanced. We will perform experiments and simulations in our laboratory, with selected tests to be flown aboard NASA's KC-135 research aircraft.

Faculty:
R. Glynn Holt, J. Gregory McDaniel

Back to top

Sonoluminescence in Space

Sonoluminescence is the term to describe the emission of light from a violently collapsing bubble which is acoustically levitated in water. Sonoluminescence ("light from sound") is the result of extremely nonlinear pulsations of gas/vapor bubbles in liquids when subject to sufficiently high amplitude acoustic pressures. In a single collapse, a bubble's volume can be compressed more than a thousand-fold in the span of less than a microsecond. Even the simplest consideration of the thermodynamics yields pressures on the order of 10,000 ATM, and temperatures of at least 10,000K. On the face of things, it is not surprising that light should be emitted from such an extreme process. Single Bubble Sonoluminescence (SBSL) has been intensively investigated both experimentally and theoretically in the past 5 years. Despite such recent attention, there remain (at least!) 3 unexplained phenomena associated with SBSL:

1. The light emission mechanism itself

2. The disappearance of the bubble at some critical acoustic pressure, and

3. The appearance of quasiperiodic and chaotic oscillations in flash timing.

Gravity, in the context of time-varying buoyancy, is implicated in these unexplained phenomena, which have all been observed in 1g experiments. SBSL bubbles experience a time-varying buoyancy which reaches maximal excursions precisely where sonoluminescence is observed. This results in a strong nonlinear coupling between volume and translatory motions. Removing the acceleration of gravity from the system will eliminate buoyancy-driven translatory oscillations of the bubble. Our goal in this project is to perform careful experiments coupled with relevant numerical modeling in order to understand bubble dynamics and light emission in variable acceleration environments. We will perform experiments and simulations in our laboratory, with selected tests to be flown aboard NASA's KC-135 research aircraft.

Faculty:
R. Glynn Holt, Ron Roy

Students:
Sean Wyatt, Charles Thomas

Back to top

Flow-Structure Interaction Noise Predicted from RANS (Reynolds Average Navier-Stokes) Computations of the Blocked Wall Pressure

Use of fluid dynamics (hemodynamics) and structural mechanics to study male impotence as a function of geometry, intracavernosal pressure and cavernosal as well as tunical material properties. Theoretical determination of penile buckling forces and non-invasive determination of cavernosal tissue fibrosis.

Faculty:
Prof. Michael Howe

Related Projects:
A New Approach to 2-D LAS Simulation of Aerodynamic Flow

Back to top

Vibration Damping of Flaps and Airfoils

Faculty:
Prof. Michael Howe

Related Projects:
Non-Equilibrium Modeling of Complex Turbulent Flows

Back to top

Ocean Wave Energy

Only two thousandths of the ocean's power would supply the entire world's power (Jouanne, 2007). We are creating and researching technologies for harvesting this power in a cost-effective way.

Faculty:
J. Gregory McDaniel

Back to top

Automotive Brake Squeal

Automotive companies in North America spend approximately one billion dollars every year on warranty costs associated with brake squeal. This estimate does not include other vehicles, such as trucks and buses, nor does it include out-of-warranty costs. Recognizing that significant design changes to brake systems are not economically feasible, this research develops and interrogates models of advanced damping treatments that mitigate brake squeal.

Faculty:
J. Gregory McDaniel

Back to top

Steering and Mixing of Waves in Composite Structures

Composite structures support waves with strong dependences on propagation angle, enabling acoustic optimization that is not possible with isotropic materials. This research is examining the vibrational and structural acoustic implications by developing models for the steering and mixing of waves.

Faculty:
J. Gregory McDaniel, Paul Barbone, Allan Pierce

Back to top

Fluid/Elastic Wave Propagation Modeling

Faculty:
Prof. Raymond Nagem

Back to top

Acoustic Detection and Identification of Submerged Objects in Shallow Water Environment

Faculty:
Prof. Raymond Nagem

Back to top

Targeted Ultrasound Contrast Agents for Drug Delivery

This is project is a collaboration with Prof. Joyce Wong of the Department of Biomedical Engineering (BME) at BU.  Prof. Wong is developing molecules that target and bind to diseased tissue.   One barrier to her work is finding appropriate contrast agents that these molecules can be attached to so that the diseased tissue can be imaged.  One candidate is the ultrasound contrast agent, which typically consists of a gas microbubble, 1 to 5 µm in diameter, encapsulated with a thin shell.  We are investigating the use of polymer-shelled contrast agents.  The ultrasound imaging systems and scanning acoustic microscope are used to characterize the properties of the microbubbles developed in the Wong Lab.  This work is funded by the National Institutes of Health and the NSF Centre for Subsurface Sensing and Imaging Systems.

Faculty:          R.O. Cleveland,  J. Y. Wong (BME-BU).
Recent Students:          W. Duncanson (PhD)

Back to top

Steering and Mixing of Waves in Composite Structures

Composite structures support waves with strong dependences on propagation angle, enabling acoustic optimization that is not possible with isotropic materials. This research is examining the vibrational and structural acoustic implications by developing models for the steering and mixing of waves.

Faculty:
J. Gregory McDaniel, Paul Barbone, Allan Pierce

Back to top

Acoustics in Bubbly Media

Increased understanding of sound's interaction with the real ocean environment is sought via theoretical and experimental pursuits. Specifically, we seek to further understand the effects of bubbles and bubble clouds on sound propagation, with practical applications in shallow-water sonar and minehunting. Bubbles and bubble clouds are generated in the near surface layer of the ocean due to both natural processes and human activities. Common examples are breaking waves, biologics and ship wakes.

Faculty:
Ron Roy, William Carey

Students:
Preston Wilson, Ryan McCormick

Back to top

Quantatative Ultrasound Imaging

The goal of this project is to employ tomographic inversion of ultrasound data to detect HIFU lesions.  In general tomographic reconstruction of ultrasound data in the body is not practical because the limited acoustic windows into the body normally mean only limited-view backscatter data is available.  The resulting inversion problem is therefore poorly posed.  In the case of HIFU however the individual lesions are approximately ellipsoidal in shape and the approximate position and size is known a priori.  Second, the process of necrosis results in change in sound speed and attenuation inside the lesion from their nominal values. Therefore the lesion can be described using shape-based methods where it is necessary to estimate only a small number of parameters to describe the geometry of the lesion rather than determine all the acoustics properties over all space.  This makes the inversion problem tractable even with the limited view backscatter data of an ultrasound probe.

Faculty:  R.O. Cleveland,  E.L. Miller (ECE-Tufts), B. Durning (BU/ECE-Tufts).

Recent Students:    B. Ulker-Karbeyaz (Northeasten PhD 2005), A. Draudt (PhD), E. Guven (Northeastern PhD)

Back to top

Detection of Buried Mines Using Laser-Acoustic Sensors

The humanitarian search for buried unexploded mines is a problem of grave importance. In this project, we are working in conjunction with Northeastern University to develop a technique for acoustic mine detection using a high-powered CO2 laser as a sound source. When the laser impacts the soil surface, rapid heating occurs, resulting in thermal expansion and the generation of an acoustic wave that propagates into the soil. This wave scatters off of the buried object and generates a scattered field that can be remotely detected using a scanning laser Doppler vibrometer. BU's effort is focused on the physics of opto-acoustic sound generation, and on the possibility that Biot waves may be created by this novel source. The work is supported by the Army Research Office via a subcontract from Northeastern University.

Faculty:
Ron Roy, Robin Cleveland, Chuck DiMarzio (Northeastern Univ.)

Students:
Wen Li (Northeastern Univ.)

Back to top

Volume and Rigidity of the Corpera Cavernosa

Use of fluid dynamics (hemodynamics) and structural mechanics to study male impotence as a function of geometry, intracavernosal pressure and cavernosal as well as tunical material properties. Theoretical determination of penile buckling forces and non-invasive determination of cavernosal tissue fibrosis.

Faculty:
Prof. Daniel Udelson

Students:
Richard Terry(former), James L'Esperance (former), Christopher Arend (former), Daniel Sciortino (former), Justin Chavez and Haibiao Luo.

Related Projects:
Clitoral and Vaginal Mechanics
Corporal veno-occlusion

Back to top

Integrated Plasma Deposition Processing for Advanced Control of Coating Structure

Plasma spray deposition is a process used to deposit metal or ceramic coatings for thermal or corrosion protection, with applications to jet engine components and fuel cells. The process features complex plasma/particle and particle/substrate interactions, which involve significant distributions and variations. The research is focused on understanding the sources of these distributions and their effect on coating quality, and using this knowledge base to mitigate these effects through development of an intelligent control system. This requires a deeper understanding of the fundamental processing/structure relationships, which are studied using a combined experimental and modeling approach.  A major focus of the research is on the development of new sensing capabilities to more effectively study the fundamental processing/structure relationships and to enable feedback control schemes that exploit those relationships.  This work is funded by NSF.

Professors: M. Gevelber, D. Wroblewski, S. Basu
Students: M. Van Hout (MS), D. Willoughby (MS)

Back to top

Refractive and clear air turbulence in the upper troposphere and lower stratosphere

Turbulence in the Upper Troposphere and Lower Stratosphere (UTLS) can adversely impact performance of a range of aerospace systems; optical Turbulence (OpT) from fluctuations in temperature and humidity can disrupt communications, radar, and high energy laser systems and Clear Air Turbulence (CAT) can lead to aircraft upset. The main thrust of this project is characterization and analysis of turbulent layers in the stably stratified regions of UTLS, using high resolution turbulence data collected from Air Force sponsored aircraft measurement campaigns.  The research includes the study of layer formation and evolution, analysis of statistical descriptors of the flow, such as structure functions, and the identification and characterization of coherent structures.  The work also involves collaboration with Direct Numerical Simulation (DNS) researchers, to provide insights that can’t be gleaned from measurements or DNS alone, and to aid in validation of the simulations.  This work is funded by AFRL.

Professors:      D. Wroblewski
Collaboraters:  O. Cote (AFRL), J. Hacker (Flinders University, Australia), R. Dobosy (NOAA), J. Werne (NWRA/CORA).

Back to top

A multi-scale approach to understanding the mechanical and biochemical behavior of tissue engineered blood vessels

Supported by: NSF

PI: Katherine Yanhang Zhang; Co-PIs: Joyce Wong and Xin Zhang

To make functional tissue engineered blood vessels (TEBVs), it is important to understand the underlying principles that govern structural-functional integrity. The ability to mimic and control the mechanical and biochemical behavior is critical for the success of engineering functional TEBVs. The overall goal of this proposal is to understand the mechanical and biochemical behavior of the TEBVs using combined modeling and experimental approaches at both the cellular and tissue level, relate this behavior to the microstructural components – the extracellular matrix and vascular smooth muscle cells, and apply these principles to modify and control the functionality of TEBVs for specific clinical applications.

For more information:

Three ENG Professors Size Up Tissue Engineered Blood Vessels

Back to top

Micro- and Nano- Mechanics of Thin Film and Thin Film Coatings

Supported by: DARPA/MTO

PI: Katherine Yanhang Zhang

Multilayer thin film material systems abound in micro-electromechanical system (MEMS) applications, serving both passive and active structural roles. Thin film coatings have been applied to numerous MEMS structures for optical applications, insulation, biocompatibility, anti-stiction, wear and corrosion inhibition etc. through a variety of chemical surface modification processes. The growing interest in device miniaturization to micro- and nano-scale has posed a new challenge for the development of reliable design and analysis tools. The overall goal of this proposal is to understand the inelastic deformation mechanisms in thin film and coatings, relate these behaviors to the design and analysis, and apply these principles to improve the performance of devices in the sub-micron scale.

For more information:

AME’s Katherine Yanhang Zhang wins DARPA Young Faculty Research Award

Katherine Yanhang Zhang Looks to Improve Micro- and Nano-scale Devices

Back to top