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    J u n e 2 0 07
                     Message from the Chair
                     DE A R F R I E N D S A N D A L U M N I ,
                     It has been quite some time since
                                                             Award for his contributions to
                                                             engineering education, refounding
                                                             of the ME department at JHU in the
                     our last newsletter, and I would like early 1980s, and for his mentoring
                                                                                                      News Briefs
                                                                                                      n Professor Lester Su is the
                                                                                                      recipient of the 2007 Capers and
                                                                                                      Marion McDonald Award for Ex-
                     to tell you about the many exciting     of students in research.
                                                                Our Mechanical Engineering and        cellence in Mentoring and Advis-
                     things that have been happening in
                     the department. Here are just a few     Engineering Mechanics undergradu-        ing. 5/21/07
                     highlights of changes that have oc-     ate programs have been success-
                                                                                                      n Dr. Raul B. Cal of the
                     curred since the last newsletter:       fully reaccredited for six years, due
                                                                                                      Turbulence Research Group
                         We have established a student       in large part to the efforts of Prof.
                                                             Charles Meneveau.                        has been awarded a prestigious
                     lounge on the third floor of Latrobe
                     Hall, where undergraduate and              After 15 years of overseeing          Ford Foundation Diversity Fellow-
                     graduate students can do homework our Senior Design course, Dr.                  ship, to pursue his postdoctoral
                     and socialize between classes.          Andy Conn has now become our             research on wind-turbine-
                         We have upgraded the ME             departmental liaison to industry.        turbulence interactions in the
                                                             Senior Design is now run by our          Corrsin wind tunnel. 4/25/07
 MECHANICALJOHNS                                             lab coordinator, Mr. Mike Johnson,

                                                             who is assisted by graduate student      n Debbi Donhauser, administra-
                                                             teaching assistants, and supervision     tive manager, is the recipient of
                                                             at the highest level by the depart-      the 2007 Whiting School of Engi-
                     Machine Shop with a new CNC             ment chair.                              neering Staff Service Award. The
                     Milling Machine. Students now have         I am happy to report that the
                                                                                                      annual award is given to one staff
                     access to the shop after they undergo departmental budget is balanced, and
                                                                                                      member in the entire school in
                     a rigorous safety/training course,      that the office staff functions like a
                     and can use it when doing their         “well-oiled machine.” This is due in     recognition of outstanding service
                     senior design projects. In addition,    large part to the efforts of Ms. Debbi   in support of the educational and
                     ME students can use the shop for        Donhauser, who was honored recently      research activities of the Whiting
                     extracurricular projects such as the    with the 2007 Whiting School Staff       School, its departments, and the
                     JHU mini-baja vehicle team, which       Service Award, which is given each       university. 4/4/07
                     had a successful finishing in a recent  year to only one staff member in the
                     national competition.                   whole engineering school.                n Of the few coveted National
                        We have embarked on substantial         I have enjoyed my three years as      Science Foundation graduate
                     curriculum reform. In the old days,     chair, and will be returning to life     fellowships awarded annually, 10
                     ME students would partially fill their as a regular faculty member this          have been awarded to students
                     first two years by taking Intro to ME, summer. I have seen the JHU ME de-        in this department over the last
                     Physics I, Statics, Strength of Materi- partment from the perspective of an
                                                                                                      two years: graduate students Amy
                     als, Dynamics, and Intro to Comput-     undergraduate (’84–’88), pre-tenure
                                                             faculty member (’92–’01), full profes-   Blank, Eatai Roth, Tom Wedlick,
                     ing all as separate courses. We are
                     condensing these into fewer courses     sor (’01–’04), and chair (’04–’07).      and Rita Wright, and undergradu-
                     with minimal repetition and maximal Each change has been very insightful,        ate students Reuben Brewer, Em-
                     integration by teaching a new course    and I’m sure that with the robotics      ily Kumpel, and Mary Wu. NSF
                     series in the department. Prof. Allison faculty (including myself) moving        Fellowship honorable mentions
                     Okamura is leading this effort.         from Latrobe Hall into the new Com-      were awarded to undergraduate
                         Since the last newsletter, Louis    putational Science and Engineering
                                                                                                      students Joe Romano and Tim
                     Whitcomb was promoted to full           Building this summer, the next few
                                                                                                      Rupert. 4/3/07
                     professor, and both Allison Oka-        years will be equally challenging and
                     mura and Jean-Francois Molinari         exciting.                                n In 2006 and 2007, six Mechani-
                     were promoted to associate profes-         The future of Mechanical Engi-        cal Engineering students won
                     sor (which under our new system at      neering at JHU looks bright indeed,
                                                                                                      NDSEG (National Defense Science
                     JHU carries tenure). Prof. Molinari     and I wish my successor, Prof. Kevin
                                                                                                      and Engineering Graduate Fel-
                     has subsequently moved back to his Hemker, a most successful tenure as
                     native France but maintains ties to     the new chair of the department.         lowship) awards (Reuben Brewer,
                     the department.                            All the best,                         David Helmer, Matthew Jeffrey,
                         Prof. Bill Sharpe has been honored     Greg Chirikjian                       Chris Kovalchick, Tom Wedlick,
                     with the ASEE Ralph Coats Roe              Professor and Chair                   and Mary Wu). 4/1/07

               News Briefs
                News Briefs                           n Professor Bill Sharpe installed an   n Lester Su received the 2006
                                                      optical strain gauge on a high-fre-    William H. Huggins Excellence in
               n Prof. Noah Cowan’s recent paper      quency, high-temperature, fatigue      Teaching Award, which was pre-
               in the Journal of Neuroscience was     test machine at the University of      sented at Convocation. 4/14/06
               rated as a “Must Read” by two          Michigan. The DARPA-sponsored          n Undergraduate student Reuben
               members of the Faculty of 1000.        system operates at 20 kilohertz        Brewer has been named one of 15
               The paper, coauthored with neuro-      and can measure strains at tem-        Hertz Foundation Fellows from
               scientist Eric Fortune, was a recent   peratures as high as 600C. 10/1/06     across the United States. 4/13/06
               feature in the JHU Gazette, and is
                                                      n Professor Noah J. Cowan, in          n For their work in the Ready, Set,
               part of an ongoing NSF-funded col-
                                                      collaboration with Professor Greg      Design project, student coordina-
               laboration. 2/9/07
                                                      Hager in the Computer Science          tors Emily Kumpel, Olivia Mao,
               n Top 10: JHU Mechanical Engineer-     Department, received a research        Angela Pelletier, Sarah Webster,
               ing has been ranked #7 in the Aca-     award from the National Science        and Professor Lester Su have been
               demic Analytics Faculty Scholarly      Foundation to study “Vision-Based      awarded a 2006 Diversity Recog-
               Productivity Index of U.S. doctoral    Control of Mechanical Systems via      nition Award from the Diversity
               programs in Mechanical Engineer-       Sampling Kernels.” 9/1/06              Leadership Council. 4/4/06
               ing. 1/29/07
                                                      n Professor K.T. Ramesh and            n Special research assistant Jeff
               n The American Geophysical Union       former graduate student Dexin          Jarosz has been been awarded a
               has awarded graduate student           Jia received the M. Hetenyi Award      2006 Diversity Recognition Award
               Saikiran Rapaka an Outstand-           from the Society of Experimental       from the Diversity Leadership
               ing Student Poster Award for his       Mechanics for their work on min-       Council for his work with groups
               presentation, titled “Critical Times   iaturization of Kolsky bar systems.    such as the Whiting School of
               for the Onset of Density-Driven        6/6/06                                 Engineering Diversity Council and
               Convection in Anisotropic Porous       n Undergraduate student Alican         Society of Hispanic Professional
               Media,” at the AGU Fall meeting in     Demir received a Provost’s Under-      Engineers. 4/4/06
               December 2006. 1/28/07                 graduate Research Award for his        n Graduate student Steve Martin
               n The American Academy of              work on tactile sensing in Prof.       has been awarded the Link Founda-
               Mechanics has elected Professor        Noah Cowan’s LIMBS Labora-             tion Fellowship in Ocean Engineer-
               Charles Meneveau as Fellow in          tory. The project is titled “A New     ing. 4/4/06
               recognition of outstanding contribu-   Approach in Tactile Sensing: Fiber
                                                                                             n Undergraduate student Chris
               tions to research and leadership in    Optic Array Sensor.” 4/24/06
                                                                                             Kovalchick was selected to serve as
               Mechanics. 1/2/07                      n Graduate student Francesco           a Young Trustee on the Johns Hop-
               n Professor Greg Chirikjian was        Soranna, Dr. Yi-Chih Chow, Dr.         kins University Board of Trustees.
               an invited speaker at the 16th Fall    Oguz Uzol, and Professor Joe Katz      Chris was also recognized recently
               Workshop on Computational and          have won the Knapp Award from          with an honorable mention on
               Combinatorial Geometry at Smith        the ASME Fluids Engineering Divi-      USA Today’s 2006 All-USA College
               College. 11/7/06                       sion, which is given to the authors    Academic Team and an honorable
               n In a recent issue of The Physical    of the best paper dealing with ana-    mention in the National Science
               Review Letters postdoctoral fellow     lytical, numerical, and laboratory     Foundation graduate fellowship
               Dr. Laurent Chevillard and Profes-     research. 4/14/06                      awards. 3/14/06
               sor Charles Meneveau describe a        n Alumnus Dr. Jun Chen and Pro-        n Two Mechanical Engineering fac-
               new approach to model pressure         fessor Katz were also recognized       ulty, Professors Sean Sun and Jeff
               effects on the dynamics and geom-      with the Outstanding Paper for         Wang, received prestigious CAREER
               etry of turbulent flows. 11/1/06       2005 honor for their publication       awards from the National Science
                                                      “Measurement Science and Tech-         Foundation. 3/1/06
                                                      nology.” 4/14/06
Update0 07 2
  June 2
                                                                                 MECHANICAL ENGINEERING AT JHU

Faculty and                                                    for a single individual and simultaneously increases staff
Research                                                       efficiency by introducing two-way wireless communica-
                                                               tion connecting all people. Figure 2 shows the sound
In this section, we list all departmental faculty members      levels measured at Johns Hopkins Hospital, the WHO
with their research areas, and highlight a recent project      guidelines, and typical levels of speech.
from some of our faculty.

n Ilene J. Busch-Vishniac, Professor, Transduction, electro-
mechanical actuators, acoustic transducers, optical sensors
Control of Noise in Hospitals
Noise in hospitals is among the top three complaints
of patients, staff, and visitors, but little has been done
to address this problem. Hospital noise is important as
well because it impacts patient safety by affecting the
speed of recovery, the need for pain and sleep-inducing
medication, and the ability to communicate clearly. In
this collaborative project with James West, of Electri-
cal and Computer Engineering, we focus on character-
izing the noise found in hospitals and reducing it. Our
                                                               Figure 2: Sound levels measured at Johns Hopkins
work to date has surveyed several inpatient units at           Hospital, the WHO guidelines, and typical levels of
Johns Hopkins Hospital, the top-ranked hospital in the         speech.
U.S. We have found that sound levels are almost the
same throughout the facility, regardless of building age.      Shiyi Chen, Alonzo G. Decker Jr. Chair in Engineering and
Further, the levels are about the same as those reported       Science, Computational fluid dynamics, statistical theory and
in other hospitals scattered throughout the world, and         computation of fluid turbulence, biocomplexity, multiscaling
the levels are high enough to cause concern about speech       computing
communication and possible hearing loss to medical
staff. We have introduced two noise interventions suc-
                                                               Gregory S. Chirikjian, Professor and Chair of Mechanical
cessfully in the hospital. The first, shown in Figure 1,
                                                               Engineering, Robotics, hyper-redundant robotic manipulators,
uses custom-made sound-absorbing materials to reduce
                                                               design, kinematics, motion planning, dynamics and control of
the reverberation and lower the noise in hospital cor-
                                                               mechanisms, computational structural biology
ridors. This material uses common fiberglass covered
with an antibacterial fabric and attached to surfaces by
industrial strength Velcro.                                    n Noah J. Cowan, Assistant Professor, Robotics, vision-based
   The second intervention replaced overhead paging            control, biomechanics, machine learning
with personal communication units. This greatly reduc-         Neural Control of Locomotion in Weakly Electric Fish
es the number of people exposed to the sound intended          Animals must rapidly process sensory information to
                                                               control their locomotion. How does an animal’s nervous
                                                               system translate this information into control signals
                                                               in the brain? This collaborative project with Profes-
                                                               sor Noah Cowan in Mechanical Engineering, and Eric
                                                               Fortune in the Psychological and Brain Sciences Depart-
                                                               ment, addresses this question using a unique species of
                                                               so-called weakly electric knifefish. The fish are called
                                                               “weakly electric” because they produce tiny electric volt-
                                                               ages that enable them to “see” surrounding objects with
                                                               special electroreceptors all over the body surface. They
                                                               are called “knifefish” because of their knife-like body
                                                               shape that allows them to slip through the water using
                                                               a specialized undulatory fin (Figure 1). Curiously, these
                                                               weakly electric knifefish like to swim back and forth to re-
Figure 1: Installation of custom-made sound-absorb-            main hidden in a moving shuttle (Figure 2) using feedback
ing panels in a unit of Johns Hopkins Hospital.                from both their eyes as well as their electric sense. By driv-            /
                                                                                                                                Update0 07 3
                                                                                                                                  June 2

               ing the shuttle back and forth, the fish work to stay in the       temperature, efficiency, and lifetime. TBCs are dynamic,
               shuttle, but as the shuttle is moved at higher and higher          multi-layered, metallic-ceramic structures consisting of
               frequencies, the fish lose the ability to track the motion.        a superalloy substrate, an aluminum-rich bond coat, a
               A detailed mathematical analysis of this behavior suggests         thermally grown oxide (TGO), and a ceramic top coat.
               that the animal’s sensors and brain are “tuned” to take into       The structural integrity of the turbine blade is provided
               account Newton’s laws of motion. This project is broadly           by the single-crystalline superalloy. Environmental
               applicable because locomotor mechanics are similar in a            protection of the superalloy is accomplished with a
               wide array of animals. Thus, these data suggest that the           50-100 μm thick intermetallic bond coat. The ceramic
               neural systems that control locomotion are directly tuned          top coat is a porous Yttrium-Stabilized-Zirconia (YSZ)
               to take into account the underlying mechanics of locomo-           layer specifically designed to thermally insulate the bond
               tion.                                                              coat and superalloy from the extremely hot gases passing
                                                                                  through the engine. Spallation and failure of TBCs are
                                                                                  governed by a sequence of crack nucleation, propagation,
                                                                                  and coalescence steps that are related to the interac-
                                                                                  tions between the various layers during thermal cycling.
                                                                                  Improved knowledge of the mechanical behavior of each
                                                                                  layer as a function of lifetime is therefore a key factor in
                                                                                  developing the more efficient turbines and jet engines
                                                                                  of the future. Figure 1 shows the mechanical response
                                                                                  of a 100 μm thin bond coat layer in two different states.
                                                                                  Prof. Kevin Hemker’s group is collaborating with
                                                                                  researchers in other universities (Harvard, Princeton,
                                                                                  University of Michigan, and UCSB) and aerospace in-
                                                                                  dustries to perform a wide variety of mechanical tests on
                                                                                  each of the layers of a TBC. These tests form the basis of
                                         Figure 2: A: Schematic of                performance and lifing models.
                                         our computer-controlled
                                         moving shuttle. B: Overhead
                                         view, showing the location of
                                         the shuttle r(t) (green),
                                         location of the fish x(t)
               Figure 1: View from       (magenta), and the resulting
               beneath a weakly electric error signal e(t) (blue).
               knifefish hiding in a

               Andrew S. Douglas, Professor and Associate Dean, Mechan-
               ics of compliant materials and soft tissues, including the kine-
               matics of the heart and the tongue, compliant active materials

               n Kevin J. Hemker, Professor, Microsample tensile test-
               ing, advanced structural materials, thermal barrier coatings,
               MEMS, nanocrystalline materials                                    Figure 1: Comparison between as received and near
                                                                                  end of life bond coat properties: The ultimate strength
               Microscale Experimental Techniques for Thermal                     of the thermally cycled bond coat is reduced signifi-
               Barrier Coating Development                                        cantly during service.
               Globalization, environmental awareness, and fuel effi-
               ciency are some of the most important factors driving the
               development of today’s land and aero-based turbines. In               Many of the components in modern thermal barrier
               recent years, thermal barrier coatings (TBCs) have been            coatings are on the order of a few hundred microns thick
               developed to successfully protect the components in a              and usually very difficult to evaluate using conventional
               turbine that are exposed to the highest temperatures. As           mechanical testing setups. In Prof. Kevin Hemker’s lab,
               a result, TBCs are now commonly used in gas turbines               numerous techniques are available for extracting data on
               and jet engines to increase the overall system operating           the strength, stiffness, ductility, thermal expansion, and
                                                                                  creep response of today’s latest thermal barrier systems.
Update0 07 4
  June 2
                                                                                      MECHANICAL ENGINEERING AT JHU

                                                                     n Joseph Katz, William F. Ward Sr. Distinguished Profes-
                                                                     sor of Mechanical Engineering, Experimental fluid mechanics,
                                                                     quantitative visualization of complex flows, turbomachines,
                                                                     breaking waves, bubbly and cavitating flows, stratified shear
                                                                     flows and oceanographic flows, PIV, holography
                                                                     Detailed Measurements of Turbulence in Axial
Figure 2 shows the gage section of a bond coat sample
being tested in tension at 1100oC; the sample width is               Turbomachines
approximately 500 μm.                                                Axial turbomachines are widely used with applications
                                                                     ranging from high capacity water pumps to jet engines.
                                                                     Accurately modeling the inherently unsteady and turbu-
                                                                     lent flow within these machines is essential in order to
n Cila V. Herman, Professor, Experimental heat transfer and
                                                                     design for optimal efficiency while controlling vibra-
fluid mechanics, boiling in microgravity and under the influence     tion and noise. Computational modeling can be a useful
of electric fields, thermoacoustic refrigeration, heat transfer in   alternative to the costly process of manufacturing and
oscillating flows, heat exchangers                                   testing prototypes, but its accuracy needs to be checked
Visualization of the Thermoacoustic Effect                           with detailed experimental data.
Thermoacoustic refrigerators have simple designs with                   Detailed measurements of flow in turbomachinery are
essentially no moving parts and are attractive because               now possible in Prof. Katz’s Laboratory for Experimental
they eliminate the need for harmful refrigerants such as             Fluid Dynamics, thanks to index-matching.
CFCs. Detailed measurements on the associated processes
are being performed in Prof. Cila Herman’s Heat Transfer
Laboratory. Temperature fields in the stack region of the
thermoacoustic refrigerator are visualized using holo-
graphic interferometry. The images below show from full
compression (top left) in the acoustic cycle—heat flows
from the fluid into the stack plate—to full expansion in
the acoustic cycle (bottom right).

                                                                     Figure 1: Test section of the axial turbomachine. The
                                                                     second stage rotors and stators are made of transparent
                                                                        The blades of the turbomachine are made of transpar-
                                                                     ent acrylic and the working fluid has the same index
                                                                     of refraction, allowing full optical access with minimal
                                                                     refractions. In one recent study, Particle Image Velocim-
                                                                     etry (PIV) data were obtained at 10 different rotor phases
                                                                     covering one rotor blade-passing period, and at mid-span.
                                                                     In comparing the measurements with computational
                                                                     model predictions, it was found that, although there is
                                                                     reasonable agreement in general between the experimen-
Figure 1: Visualization of thermoacoustic effect from                tal results and the computational simulations, some criti-
full compression (top left) in the acoustic cycle—heat               cal flow features are not correctly predicted. The turbulent
flows from the fluid into the stack plate—to full                    kinetic energy levels are generally too high in the simula-
expansion in the acoustic cycle (bottom right).
                                                                     tions, with substantial amount of unphysical turbulence
                                                                     generation near the blade’s leading edges. Also, wake
                                                                     diffusion is underestimated. The results highlight the use-
                                                                     fulness of comparisons that cover the entire unsteady flow
                                                                     in a passage, as afforded by the present large data base.                /
                                                                                                                                     Update0 07 5
                                                                                                                                       June 2

               Figure 2: Turbulent kinetic energy (k) distribution
               comparison for two sample rotor phases (top and bot-
               tom rows). Flow is from right to left. Rotor tip speed,
               Utip = 8 m/s; Stage Length, Ls = 203 mm.

               Omar M. Knio, Professor, Computational fluid mechanics,
               reacting shear flows, physical acoustics, atmospheric and oceanic
                                                                                    Figure 1: Streamwise velocity contours of flow over frac-
               flow, energetic materials, microfluids, uncertainty quantification   tal tree. Left: full simulation with five generations of
                                                                                    branches. Top right: Renormalized Numerical Simula-
                                                                                    tion (RNS) in which only the trunk and a 1st genera-
               n Charles Meneveau, Louis M. Sardella Professor in Me-               tion branches are resolved, the rest is represented with
               chanical Engineering and Director, Center for Environmental          a distributed force-field shown in grey. Bottom right:
               and Applied Fluid Mechanics, Theoretical, experimental, and          resulting stream-wise velocity contours.
               numerical studies in turbulence; Large-Eddy Simulation and
               turbulence modeling, fractals and scaling in complex systems         n Allison M. Okamura, Associate Professor, Robotics,
               Computational Modeling of Turbulent Flow over
                                                                                    virtual and teleoperated environments, haptic interfaces, medical
                                                                                    robotics, tissue modeling, robotic fingers and hands
               Complicated Objects
                                                                                    Superelastic Surgical Robots
               What is the drag force of wind flowing over a fractal
               tree? How can we model efficiently the flow over com-                By designing very small robots using superelastic ele-
               plex multi-scale boundaries without having to resolve                ments, we are extending the reach of surgeons into very
               all the fine-scale details of the object? Former graduate            small and confined locations in the human body. Toward
               student Stuart Chester and Professor Meneveau have                   this goal, we are currently pursuing two distinct projects:
               recently developed a new computational technique called              steerable needles and active cannulas. Steerable needles
               Renormalized Numerical Simulation (RNS). It allows                   (Figure 1) are much like normal needles except that they
               efficient computer modeling of interactions between                  are made from superelastic nitinol, which is very flexible.
               turbulence and multi-scale objects when they can be                  This flexibility amplifies the bending effect of the wedge-
               described as scale-invariant objects, i.e., fractals. In the         like bevel tip as the needle is pushed into tissue. By
               figure is shown (left) a full simulation of flow over a              robotically controlling the axial spin of the needle, one
               “Cartesian tree” with five generations of branches.                  can control the direction the needle tip will go as it
                  The idea behind RNS is that the same results may be               travels through soft tissue. Driving the needle is actually
               obtained by simulating only a few “large-scale genera-               much like driving a car or bicycle: it is a nonholonomic
               tions” and measuring their effects on the flow (lower                system. Using nonholonomic models, we are currently
               right). This effect is then parameterized with an effec-             developing automatic controllers and teleoperation
               tive drag coefficient. This same coefficient is then used            techniques to drive the needle to surgical targets using
               in the modeling of small-scale unresolved branches. This             feedback from medical imaging systems. This work is
               method effectively is a computational analogue of the                in collaboration with Noah Cowan and Greg Chirikjian
               time-honored method of “similitude” and model testing                (JHU) and Ken Goldberg (UC Berkeley).
               in which dimensionless parameters are obtained from
               scaled models placed in a wind tunnel. Here the testing
               is being done on the fly during the simulation, at large
               scales. As a next step, wind-tunnel and water channel
               tests are being planned to compare predictions from RNS
               to laboratory measurements in real systems.

                                                                                    Figure 1: Steerable needles harness the bending effect
                                                                                    of the wedge-shaped bevel tip to steer through tissue.
Update0 07 6
  June 2
                                                                                      MECHANICAL ENGINEERING AT JHU

   Active cannulas (Figure 2) are similar to steerable nee-          failure of the entire structure. These large numbers of
dles, but do not need to be inside soft tissue to steer. They        cracks talk to each other through stress waves, and the
are made from telescoping pre-curved superelastic tubes.             resulting fragment size distribution depends on the way
Pushing the tubes in and out of each other and rotating              the cracks nucleate, the way they communicate, and the
them axially creates interesting “snake-like” dexterous              way they fly.
motion that can be used to enable surgical interventions                   Together with Dr. Fenghua Zhou (now at Ningbo
deep inside difficult-to-reach areas of the human body. We           University in China) and Professor Jean-Francois Molinari
are developing beam mechanics–based models describing                (now at Ecole Normale Superieure in Cachan, France),
how the tubes cause each other to bend, allowing us to               we have performed fundamental theoretical, computa-
use them as miniature curved robot arms. Using image                 tional, and experimental investigations into the influence
feedback, we can plan optimal paths for active cannulas to           of material and structural parameters on the mechanics
reach useful surgical sites. The doctor can then use them            of fragmentation of brittle materials. Expressions for a
to accomplish the surgical objective. This work is in col-           characteristic fragment size and a characteristic strain rate
laboration with Noah Cowan (JHU).                                    have been derived, and the average fragment size is calcu-
                                                                     lated for a wide variety of strain rates and a broad range
                                                                     of material parameters. We have also derived an empirical
                                                                     function that relates the normalized fragment size s/s0 to
                                                                     the normalized strain rate and that fits all of the numeri-
                                                                     cal results with a single master curve (Figure 1). The
                                                                     model predicts smaller fragment sizes that are typically
                                                                     assumed, and also provides a distribution of fragment
                                                                     sizes that can be compared with experiment.

Figure 2: Active cannulas are mm-scale curved robot
arms that dexterously reach confined surgical sites.

Andrea Prosperetti, Charles A. Miller Jr. Distinguished
Professor of Mechanical Engineering, Theoretical and computa-
tional fluid mechanics and acoustics, multiphase flow, ther-
moacoustic processes, gas and vapor bubble acoustics, microfluidic

n Kaliat T. Ramesh, Professor and Director, Center for Ad-
vanced Metallic and Ceramic Systems, Nanostructured materi-
als, high strain rate behavior and dynamic failure of materials,
biomimetics and active materials
The Dynamics and Energetics of Fragmentation
                                                                     Figure 1: The fragmentation of a very large number of
                                                                     materials can be represented in terms of a single model that
A common consequence of an impact is fragmentation.                  includes both the dynamics and energetics of the process.
Whether the impact is that of an asteroid into the earth,
or an antitank weapon into a tank, or of one missile
into another (as in the missile defense problem), it is              n William N. Sharpe Jr., Alonzo G. Decker Professor of
always necessary for us to obtain some understanding                 Mechanical Engineering, Experimental solid mechanics, testing
of the resulting debris cloud, i.e., of the fragmentation.           of small specimens, mechanical properties of MEMS materials
Fundamentally, fragmentation occurs because the large                Tensile Properties of Thin Gold Film
amounts of energy associated with the impact have to
be absorbed, and this can only be achieved through the               The specimen is one micron (one-millionth meter) thick
development of very large numbers of cracks (or shear                and 150 microns wide by two millimeters long in the
bands or voids). Under more conventional (static) condi-             straight section. The film is deposited on a silicon wafer
tions, one only generates a few cracks, and correspond-              and photolithography creates a pattern around the entire
ingly only a few fragments. However, in an impact event,             specimen to allow etching away of the wafer underneath
thousands to millions of cracks may be nucleated before              the gold. The left end remains attached to the film on the
any one of the cracks can grow large enough to cause                 wafer, and four tiny straps, which are broken before test-               /
                                                                                                                                     Update0 07 7
                                                                                                                                       June 2

                                                                                 Experiments and Simulations of Mixing in Turbulent
                                                                                 Energy systems that rely on combustion are the subject
                                                                                 of widespread efforts aimed at increasing efficiency and
                                                                                 controlling pollutant generation. Recent rapid advances
                                                                                 in computational power have brought within reach the
                                                                                 possibility of simulating accurately the performance of
               Figure 1. A gold tensile specimen.                                realistic combustion systems. Accurate computer simula-
                                                                                 tions would simplify the design and development of
                                                                                 combustion systems by reducing the need for expensive
                                                                                 testing of physical prototypes. However, numerous chal-
                                                                                 lenges remain for combustion simulations. Among these
                                                                                 challenges is the proper representation of the process by
                                                                                 which the fuel and oxidizer species mix at the molecular
                                                                                 level, in the presence of turbulence in the underlying
                                                                                 fluid flow. Professor Lester Su’s group is attempting to
                                                                                 understand the turbulent fluid mixing process in a way
                                                                                 that will serve efforts to simulate reacting flows, using a
                                                                                 comprehensive approach that combines experimental and
                                                                                 computational tools to study mixing in the well-defined
                                                                                 turbulent jet flow system. One facet of this work involves
                                                                                 jet simulations using the promising Large-Eddy Simula-
                                                                                 tion (LES) method. In LES much of the turbulent activity
                                                                                 is entrusted to models, rather than being computed
                                                                                 explicitly. Complementary to these simulations, Professor
               Figure 2. Gold stress-strain curves
               ing, support the wide right end. A thin silicon fiber (a bit
               bigger than a human hair) is glued to the right end; it is
               connected to a force transducer and piezoelectric actuator
               to pull the specimen until it breaks. The results of an ex-
               tensive series of tests on gold film of three different thick-
               nesses—0.15, 0.5, and 1.0 micron—are shown in Figure
               2. All three show a strength that is very much higher than
               larger specimens of pure gold; this is a common observa-
               tion and related to the microscopic mechanisms of ductile
               material behavior. However, the thinnest material is much
               more brittle, i.e., cannot elongate to a very large strain.       Figure 1: Typical mixing field from the jet simulation,
                  This film—only 150 nanometers thick—contains tiny              in which the jet fluid (depicted as red) issues into still
               pores that cause it to fail at smaller strains. Gold film is      surroundings (depicted as blue).
               widely used in the microelectronics industry to connect
               transistors and other electronic devices on circuit boards.
               One must know its mechanical properties to properly
               design systems that can withstand thermal expansion/
               contraction and shock /vibration loading. The Sensors
               and Electronic Devices Directorate of the Army Research
               Laboratory sponsored this work.

               n Lester K. Su, Assistant Professor, Experimental fluid
               mechanics, turbulent mixing and combustion, laser diagnostics,
               interaction of experiments and simulations, combustion systems,
               spray and droplet dynamics                                        Figure 2: Dilution of jet fluid concentration on the jet
                                                                                 centerline as the fluid moves downstream, for two dif-
Update0 07 8
  June 2
                                                                                 ferent mixing model specifications.
                                                                                   MECHANICAL ENGINEERING AT JHU

Su’s group performs laser diagnostic experiments in the
same flow system. Data from the experiments informs the
                                                                 n Tza-Huei (Jeff) Wang, Assistant Professor, BioMEMS,
specification of the mixing models for the simulations,
and also serves as benchmarking data for the simulation          microfluidics, nano/microfabrication, experimental molecular
results. Figure 1 shows a typical mixing field from the jet      dynamics, single molecule detection and manipulation
simulation, in which the jet fluid (depicted as red) issues      Single Molecule Detection and Manipulation
into still surroundings (depicted as blue). Figure 2 shows
how the jet fluid concentration on the jet centerline is         Our understanding of chemistry and biology comes
diluted as the fluid moves downstream, for two different         almost exclusively from experiments on ensembles of
mixing model specifications. Comparing these simula-             molecules, by which a vast number of duplicate behav-
tion results with the experimental data allows a direct          iors are investigated and averaged responses are recorded.
assessment of the validity of the models.                        However, a lot of important information for fundamental
                                                                 genomic and proteomic exploration, such as intermedi-
                                                                 ates and time-dependent pathways of molecular interac-
n Sean Sun, Assistant Professor, Mechanics of motor proteins,    tions, is difficult to identify by the ensemble methods.
statistical mechanics of soft condensed matter, semi-classical   The ability to make measurements at the single molecule
dynamics                                                         level provides information on time trajectories of indi-
                                                                 vidual objects and their conformational fluctuations that
Elastic Properties of Protein Structures
                                                                 help lead to a detailed understanding of heterogeneities
Proteins are biological macromolecules that undergo              in a system that would otherwise be hidden. Professor
large conformational dynamics. Predictions of conforma-          Jeff Wang’s lab is interested in developing new technol-
tional changes using all-atom simulations are computa-           ogy platforms for analysis of single biomolecules (DNA,
tionally unfeasible. Prof. Sean Sun is developing coarse-        RNA, and protein). A high-throughput single molecule
grained elastic models to describe protein deformations.         tracing platform for quantification of low-concentration
Together with postdoc Seungho Choe and Prof. Charles             DNA has been developed based on confocal spectroscopy
Wolgemuth at University of Connecticut, Prof. Sun                and microfluidic manipulations. Fluorescence of mo-
showed that protein secondary structures have common             lecular beacon probes, emitting upon hybridization with
structural properties and behave like simple mechanical          complementary target sequences, is resolved at the single-
objects. His model, for example, can predict bending             molecule level using a confocal fluorescence spectroscope.
and twisting properties of proteins such as a coiled coil,       Transport of individual molecules is precisely directed
shown in the figure. Other protein structures such as            through a minute confocal detection region via electro-
beta-sheets (lower figure) can be described similarly.           kinetic forces on a microfluidic chip, achieving accurate
                                                                 and high-throughput analysis of biomolecular targets.
                                                                 This technique enables accurate quantification of biomol-
                                                                 ecules at low-abundance and is capable of detecting subtle
                                                                 changes in molecular quantities such as gene expression
                                                                 changes in a singe cell. Thus, this technology provides an
                                                                 effective platform for exploring the heterogeneities in a
                                                                 biological system unattainable by conventional methods.

                                                                 Figure 1: Schematic view of single molecule detection
Figure 1: Proteins are made of universal secondary struc-        and manipulation
tures such as alpha-helices and beta-sheets. A coiled coil
is a common protein structure made of bundled alpha-
helices. Prof. Sun and colleagues showed that components
of the protein structure have mechanical rigidity and can        Louis L. Whitcomb, Professor, Nonlinear dynamical systems,
be described using continuum elastic theories. The theory        design, and model-based control of mechanical systems, including
is generic and can explain energy scales associated with         underwater robotics vehicles, robot arms, and medical robotics.
conformational changes seen in proteins.                                                                                                     /
                                                                                                                                    Update0 07 9
                                                                                                                                      June 2

                                                     Varjola Nelko                                    MSE
               List of Graduate Degrees awarded      Lin Pei                                          PhD
               in 2006 and 2007                      Don “Woody” Pfitsch                              MSE
                                                     Muge Pirtini                                     MSE
               May 2006:
                                                     Carlos Rosales                                   PhD
               Jake Abbott                     PhD
                                                     Jian Sheng                                       PhD
               Takintope Akinbiyi              MSE
                                                     Aris Skliros                                     PhD
               Aaron Beattie                   MSE
                                                     Murray Snyder                                    PhD
               Lorenzo Botto                   MSE
                                                     Daniel Ursu                                      MSE
               Marcelo Chamecki                MSE
                                                     Derek Warner                                     PhD
               Shu-Yi Chao                     MSE
                                                     Sarah Webster                                    MSE
               Kevin Connington                MSE
                                                     Tomonori Yamamoto                                MSE
               Jin Seob Kim                    PhD
                                                     Weihong Zhu                                      PhD
               Reuben Kraft                    MSE
               Jusuk Lee                       MSE
                                                     Bachelor of Science in Mechanical Engineering
               Kiju Lee                        MSE
                                                     awarded May 2006
               Zan Liu                         MSE
               Xiaozhen Lu                     PhD   Ashwini Anjanappa, Candace Brakewood, Reuben
               Luka Luznik                     PhD   Brewer, Ryan Chapman, Lauren Denk, Tristan Flanzer,
                                                     Giles Haysom, David Helmer, Omar Irizarry, Benjamin
               Ian McKelvey                    MSE
                                                     Jackson, Matthew Jeffrey, Jonathan Kracht, Peter Kuhn,
               Tabish Mustufa                  MSE   Emily Krumpel, Joseph Lee, Boyang Li, Peter Lillehoj,
               Angela Pelletier                MSE   Robert Lontoc, Olivia Mao, Marcelo Porto, Michael
               Ramesh Raghupathy               MSE   Scheib, Kwame Small, Daniel Touchette, Eiline Yoon
               Yo-Rhin Rhim                    MSE
               Adam Schuyler                   PhD   Bachelor of Science in Mechanical Engineering
               Michael Sharma                  MSE   awarded May 2007
               Michael Shumski                 MSE   Matthew Baldwin, James Barker, John Benedetto, Joshua
               Misty Steinberger               MSE   Chang, Ovinandan Chatterjee, Alic Chen, David Chow,
               Lawton Verner                   MSE   John Criezis, Alican Demir, Peter Dewey, Evan Earnest,
               Carole Womeldorf                PhD   Scott Hoffmann, Byong Ho Hwang, Joshua Kelley, Joseph
                                                     Kim, Rebecca Kramer, Philip Kwon, Justin Loffredo,
               Binze Yang                      PhD
                                                     Laura Manofsky, Nicholas Marchuk, Ryan Mayes, Ryan
               Quan Zhang                      MSE   McCaffrey, Evan Miller, Robert Ng, Samuel Olesky,
               May 2007:
                                                     Thomas Potter, Penny Robinson, Timothy Rupert, Juan
                                                     Sanchez, Konstantinos Sarafidis, Keith Schellhorn, Aaron
               Justin Caulfield                MSE
                                                     Schlothauer, Michael Squibb, Sairam Subramanian, Ian
               Stuart Chester                  PhD   Wing, Brian Woodworth
               Xu Geng                         PhD
               Daniel Gianola                  PhD
                                                     Bachelor of Science in Engineering Mechanics
               Netta Gurari                    MSE   awarded May 2006
               Piyush Jain                     PhD
                                                     Christopher Kovalchick, Ashley Schwarzmann, Benjamin
               Alireza Kermani                 MSE
               James Kinsey                    PhD
               Axel Krieger                    MSE
                                                     Bachelor of Science in Engineering Mechanics
               Michael Kutzer                  MSE
                                                     awarded May 2007
               Lauren Mace                     MSE
               Peter McPhee                    MSE   Soohong Park, Joe Romano, Hubert Tseng, Mengnan
               Jessica Meulbroek               MSE   “Mary” Wu

Update0 / 10
  June 2 07
                                                                              MECHANICAL ENGINEERING AT JHU

Senior Design                                                work. This desk allowed for easy access to her keyboard,
Projects 2005–2006                                           to the ports on her computer, and to a new printer-fax-
                                                             scanner-copy machine. A second desk, a portable unit,
                                                             was also built to support a laptop computer. This was
Project AWESOME                                              to be used while the client was seated in her motorized,
                                                             high-tech wheel chair in her living room. She often has
(Alternating Wind Energy System for Optimizing               visitors coming to work with her, and thus this portable
Mechanical Efficiency)                                       desk allowed her to easily interact with them. It featured
                                                             a built-in turntable that allowed the laptop to be spun
The objective of this project was to develop a way to        around for viewing by all.
modify a small, wind-driven generator, such as is used
to provide electrical power and to charge up a battery       Sponsor:
onboard small pleasure boats. The modification involved      The Volunteers for Medical Engineering and the JHU
introducing to the power train a new and unique power        Department of Biomedical Engineering
transmission mechanism invented by the sponsor, to           Sponsor Contact:
allow more efficient utilization of the ever-varying wind    Mr. John Staehlin
power that is the input to the system. This totally
                                                             Project Designers:
mechanical device is called the IVMC, standing for Infi-
                                                             Boyang Li, Olivia Mao, Eiline Yoon
nitely Variable Motion Control. A specialized version of
the IVMC—the IVT (Infinitely Variable Transmission)—
was used in Project AWESOME. It provides the ability
to smoothly output a constant RPM and torque, despite        Project HIT IT
variations in the input to the system. This team created     (Heavy Instrumental Tool for Impact Testing)
the means to provide a feedback-actuated power-transfer
                                                             This team was asked by their sponsor to develop a
regulator for the IVT, which allowed for an increase in
                                                             Charpy Impact test machine that was capable of deliver-
the useful wind-speed range, as well as a smoothing of
                                                             ing up to 350 foot-pounds of energy to the specimen
the wind speed versus output power curve.
                                                             to be fractured. The existing Charpy machine at the
Sponsor:                                                     NSWC materials laboratory only had a capacity of 240
DDMotion Corporation                                         ft-lb., insufficient to test the newest, much tougher alloys
Sponsor Contact:                                             the Navy wanted to investigate, hence the motivation for
Mr. Key Han                                                  this project. In addition, Team HIT IT was tasked with
                                                             devising a means to automatically raise the very heavy
Project Designers:                                           mass that swings down to apply the fracturing load to
Candace Brakewood, Giles Haysom, Michael Scheib,             the specimens. This was accomplished by purchasing a
Kwame Small                                                  used machine, adding weights to its striking mass, and
                                                             then retrofitting a motorized chain drive to lift the now
                                                             78 pound weight. A new dial gage, which is needed
Project ePOD                                                 to indicate the energy absorbed by the test specimen
                                                             during fracture, also had to be created. In addition, the
(electronic Portable Office Desk)                            team developed a means to indicate the force created at
This VME project was initiated by the need to enhance        the moment of impact of the mass with the specimen,
the ability of a disabled person to continue to be able      and also developed a means to dynamically measure the
to telecommute to her job. Although plagued by an            propagation of the crack which is formed as the specimen
undiagnosed and progressive neuro-muscular condition,        is being fractured.
which greatly limited her stamina and ability to move,       Sponsor:
she has been able—albeit with growing difficulties —to       Naval Surface Warfare Center, Carderock Division
use her computer to perform her job. But, the arrange-
ment of the components in her computer system had            Sponsor Contacts:
caused her to reach and twist in ways that were becoming     Mr. Gerald Mercier, Mr. Matthew Hayden and
ever more deleterious to her health. Thus, Team ePOD         Ms. Jennifer Gaies
was charged with designing and building a new, easy-to-      Project Designers:
reach layout for her computer system, and to build, first,   Omar Irizarry, Joe Lee, Ashley Schwarzmann, James Wu
a stationary desk to be used adjacent to the hospital bed
in the bedroom in her home where she does most of her                                                                                /
                                                                                                                            Update0 07 11
                                                                                                                              June 2

               Project IBRAIL                                                The U. S. Army Research Laboratory
               (Inexpensive BRAILler)                                        Sponsor Contacts:
               Although last year’s Senior Design Project BPEN was           Mr. Timothy Kogler and Mr. Brendan Patton
               not entirely successful in reaching all of its objectives,    Project Designers:
               it showed sufficient promise to motivate the NFB to           Ovi Chatterjee, Christopher Kovalchick, Kostas Sarafidis,
               support this second effort to invent a new, lightweight,      Daniel Touchette
               inexpensive means for typing Braille. The objective of
               the NFB was to have a design that could be mass-pro-
               duced inexpensively and then supplied to those in need,
                                                                             Project MRMAST
               especially in third world countries where the level of
               Braille illiteracy is shockingly high due to the unreach-     (Mission Reconfigurable Mast for Antenna and Sensor
               able cost of existing Braille typing machines. After nu-      Testing)
               merous design iterations, and constant re-evaluations by      Although the name of this project suggests yet another
               the sponsor’s representatives, Team IBRAIL eventually         follow-up to some previous shipborne mast projects for
               devised a simple-to-use but operationally sophisticated       LMC, the mission of this year’s Team MRMAST was very
               hand-held unit that worked in conjunction with the            different. Their mast, which will be used at sea aboard
               existing plastic slates that are now used with a one-point    an experimental ship called the Sea Slice, has the job of
               stylus to slowly peck out Braille—one dot at a time. By       supporting numerous instruments such as radar units,
               providing the ability to create up to all six dots in the     other sensors, and antennas, which at times would be
               Braille cell simultaneously, this new device offered the      under evaluation by the Navy. The problem to be solved
               means to create Braille up to six times faster than before.   was to find a way to avoid having to interrupt a sea trial
               Sponsor:                                                      and return (at great expense) to the Navy shipyard in
               National Federation of the Blind                              San Diego each time even a small change or repair was
                                                                             needed with one of those instruments, perched 35 feet
               Sponsor Contacts:
                                                                             above the deck. This student design team designed and
               Dr. Betsy Zaborowski, Ms. Ameenah Ghosten, Mr. Steve
                                                                             built a full-scale, simple but very rugged mast system,
               Booth, and Mr. Mike Bullis
                                                                             fully equipped to be installed on the Sea Slice. It con-
               Project Designers:                                            sisted of two main vertical members affixed to the face of
               Emily Kumpel, Peter Kumpel, Mark MacLeod, Penny               the ship’s deckhouse, with a movable carriage carrying
               Robinson                                                      the instruments that could easily be moved up and down
                                                                             since it was powered by cables from a seaworthy hoist.
                                                                             Thus, even at sea the instruments could be brought down
               Project MISSILE                                               to deck level and worked on by the ship’s crew.
               (MIniaturized Solar Sensor for Improved TeLEmetry)            Sponsor:
                                                                             Lockheed Martin Corporation
               The need fulfilled by Team MISSILE was to develop a
               means to allow the USARL to study projectile trajecto-        Sponsor Contacts:
               ries on much smaller warhead systems than they are now        Mr. George Root, Mr. Mark Alberding, Mr. Phil Green-
               able to test. The requirements for this project asked for     wald, and Mr. Alexander Boon
               a rugged device that was half the size of the existing sun    Project Designers:
               sensors that are now being used. Other requested im-          Lauren Denk, Ondrej Juhasz, John Kracht, Peter Kuhn
               provements included achieving a design with fewer parts
               and an easier-to-assemble method, and at less cost. The
               new sensor managed to reduce the number of parts from
                                                                             Project RADAR
               12 to only seven, and used a simplified top-down method
               for assembly. Testing of a half-scale mock-up showed          (Real-Time Antenna Deflection Analysis & Readings)
               that this new design, which features a neutral density        The challenge presented to Team RADAR was to de-
               filter element to control the amount of light reaching the    velop a methodology for allowing corrections to be made
               photocell—instead of the existing set of difficult-to-in-     to radar signals when a large, shipborne antenna array
               stall and costly obstructing pillars—was able to output       suffers mechanical distortions due to a ship’s extreme
               signals that mimicked those required for this application.    motions in heavy seas. The approach suggested by NGC,
                                                                             and successfully carried out by this team, was first to cre-
Update0 / 12
  June 2 07
                                                                               MECHANICAL ENGINEERING AT JHU

ate a finite-element model (FEM) of a scaled-down por-
tion of the full antenna array. The full-sized phased array   Project TRAUMA
antenna was 12 by 12 feet, and contained 36 individual        (Tri-axial Accelerometer for
radar subarrays connected together in a 6 by 6 matrix.        Understanding Medical
The FEM and physical model created under this project         Impact Aftereffects)
had a 3 by 3 subarray matrix and was 3 by 3 feet in size.
                                                              Here again, as with several of this year’s design projects,
Comparisons were then made between the vibrational
                                                              Team TRAUMA was asked to created the equipment
shapes predicted by the FEM and the actual shapes,
                                                              needed for the early part of a program that is ongoing
measured with accelerometers, when the physical model
                                                              between the JHU CIRP and the Whiting School of En-
was shaken in a special test setup. Good agreement was
                                                              gineering. The ultimate goal of this ambitious program
seen between the two. NGC will now take these results
                                                              will be to minimize the serious head injuries experienced
and feed them into software they are developing to make
                                                              by the elderly when they fall. Among the tasks suc-
the needed compensations to the radar signals for the
                                                              cessfully completed by this student team were devising
full-scale system.
                                                              a means to measure, in real time, the accelerations of
Sponsor:                                                      the human head during a fall; developing the software
Northrop Grumman Corporation                                  needed to differentiate between an actual fall and other
Sponsor Contacts:                                             routine head motions such as during standing or while
Mr. John Staehlin, Mr. Daniel Davis, and Mr. Daran            walking; and providing a means to capture, process, and
Ossinger                                                      transmit the data to a remote location where they could
Project Designers:                                            be stored and analyzed. These data might ultimately be
Ryan Chapman, Tristan Flanzer, David Helmer, Byong            used to allow an alarm to sound when a fall occurs. Min-
Hwang                                                         iature electronic accelerometers were fitted into a small,
                                                              specially designed box that could be comfortably worn
                                                              on the head. Another box—to be carried on the belt or
                                                              in a pocket—housed the rest of this system. Extensive
                                                              testing was conducted, both with normal head motions,
(TAGGing AErial Remote System)                                then recording the falls of a Ju Jitsu expert, and finally
It is an unfortunate fact that our country must be ever       with an anthropomorphically correct dummy that the
more creative in its battles against crime and terrorism.     team designed and built, which allowed the most severe
One such tool now under development is a means to             falling modes to be documented.
mark suspect vehicles (cars, ships) by using a remotely       Sponsor:
piloted unmanned air-vehicle (RPV). Team TAGGERS              JHU Center for Injury Research and Policy
was tasked to create the first phase of this developing
                                                              Sponsor Contacts:
program, now ongoing at the JHU APL. This student
                                                              Ms. Sue Baker, Dr. Gary Surock, and Dr. K. T. Ramesh
team assembled a small, unmanned helicopter from a
hobby kit, and then attempted to retrofit it with the         Project Designers:
equipment needed to aim and shoot a paint ball gun at         Scott Chana, Matt Jeffrey, Rob Lontoc
the target. An ultra-small video camera and a range find-
er complemented this part of the system. A special gim-
bal was designed and built that allowed the two remotely      Typical senior design projects from prior years
controlled degrees of motion needed for aiming the gun.       • Tractor for disabled persons—By adding a lifting
Tests were run to determine the best place to strike a car    means, and manual controls for braking and accelerating,
and cause minimal noise and vehicle damage—it was             an ordinary farm tractor was transformed so as to be com-
determined to be the trunk area. The sponsor will now         pletely accessible for a paraplegic to operate unassisted.
take this system and proceed to introduce the desired
fully automated operation on another RPV.                     • Basketball for the blind—A small sound-emitting
                                                              device was placed in a basketball, and with another
Sponsor:                                                      sound-source at the backboard, a means for blind people
The Johns Hopkins Applied Physics Laboratory                  to play basketball and thus develop “hand-ear coordina-
Sponsor Contacts:                                             tion” was provided.
Dr. Jeff Barton and Dr. John Samsundar
Project Designers:
Ashwini Anjanappa, Reuben Brewer, Mark Porto,
Benjamin Soto                                                                                                                        /
                                                                                                                            Update0 07 13
                                                                                                                              June 2

               Senior Design                                                 Northrop Grumman Corp.
               Projects 2006–2007
                                                                             Mr. John Staehlin
               Project SUSPECT                                               Project Designers:
                                                                             Brian Woodworth, Matt Baldwin, Keith Shelhorn,
               System for Useful Space
                                                                             Andrew Pierpont
               Equivalent Cryogenic Testing
               The design and development of systems for space and
               other astronomical applications requires rigorous evalu-    Project CHARC-ATAAC
               ations of all materials, components, and subsystems that
               will make up such systems. This requires that full-scale    Advanced Tactical and Adjustable Cargo
               tests must be conducted under the cryogenic temperatures
               and vacuum conditions these subsystems will be encoun-
               tering. This project required the design and fabrication of
               a fully operational thermal vacuum test chamber, capable
               of withstanding a space-equivalent vacuum, and provid-
               ing a means to control the rate at which components are
               cooled/heated inside the chamber.
               Northrop Grumman Corp.
               Mr. John Staehlin
               Project Designers:
               Tim Rupert, Ryan McCaffrey, Scott Hoffmann, Ryan Mayes
                                                                             The goal of this project was to design and build a fully
                                                                             operational, scale-model of a Cargo Module that will fit
               Project ARODD                                                 into the propulsion hulls of a uniquely designed experi-
                                                                             mental ship, the CHARC, which is under development
                                                                             by LMCO for the U.S. Navy. A prominent feature of this
                                                                             SWATH-type vehicle is its two large, fully submerged
                                                                             propulsion hulls, which provide the CHARC’s propul-
                                                                             sion and its variable buoyancy capability that is used to
                                                                             adjust the craft’s draft and thus optimize its speed and
                                                                             sea keeping for various missions. The team built a full
                                                                             scale mock-up and tested the buoyancy control system.
                                                                             Lockheed Martin Co.
                                                                             Mr. George Root
                                                                             Project Designers:
                                                                             John Benedetto, Tom Potter, John Criezis, Juan Sanchez

               Portable Ground Based Radars often need to be rapidly         Project COBRA
               transported and set up in remote locations. When placed       Calibrator for Ballistic Accelerometers
               on rough terrain, the need to keep these large units level
                                                                             The testing and evaluation of new ballistic munitions
               can be a challenge, especially on soft and yielding ground.
                                                                             requires sensors, such as accelerometers, to measure the
               This project developed a means to automatically deploy
                                                                             performance of these new weapons under actual firing
               from a truck, and then to sense and adjust the level of
                                                                             conditions. However, to assure that valid data are being
Update0 / 14   these systems.
  June 2 07
                                                                              MECHANICAL ENGINEERING AT JHU

gathered, it is necessary to calibrate these very high per-
formance accelerometers. Under this project a machine         Project RADAR
was developed that is capable of providing the needed         Real-Time Antenna Deflection Analysis and Readings
calibrations up to 8,000 g’s.
U.S. Army Research Laboratories
Mr. T. Gordon Brown and Mr. Ben Topper
Project Designers:
Jacob Arrowsmith, Rebbeca Kramer, Peter Dewey,
Joshua Kelly, David Chow

Project bPOD
Backpack Positioning Device                                   Although mounted on sturdy frames, when a large array
                                                              of antennas is placed aboard a ship, the motions and de-
                                                              flections of the ship are transferred to the antenna array,
                                                              thus causing distortions in the signals received. Phase
                                                              compensation can be achieved to remove these signal
                                                              distortions, and this project’s objective was to develop
                                                              a way to monitor the movements and distortions of
                                                              the array, and thus provide inputs to the compensating
                                                              software. A new test stand and large model analysis were
                                                              Northrop Grumman Corporation
                                                              Mr. John Staehlin
                                                              Project Designers:
                                                              Michael Squibb, Andrea Pringle, Dave Haldane, James

This project is to help TJ, a 10-year-old boy who has         Project AFOLD
limited physical capabilities due to cerebral palsy. When     Automatic Folder
in school he would like to be able, unaided, to access the
contents of his backpack, which is now hung from the          One of this sponsor’s products is a huge, multi-stage
back area of his motorized wheelchair. Under this proj-       machine that automatically handles, folds, and stuffs pa-
ect a mechanism was developed, which TJ can control,          pers into envelopes. The folding stage requires periodic
and which allows the backpack to be moved from the            adjustments, both for each size of paper that is to be han-
back area of his wheelchair to the front, where he will       dled as well as for various folding configurations. This
then be able to easily access its contents.                   project’s objective was to provide a means to automate
                                                              what is now a tedious and difficult by-hand adjustment
Sponsors:                                                     of the components in this folding stage. A complete
Volunteers for Medical Engineering, Inc.                      redesign of the folding mechanism was accomplished.
Contacts:                                                     Sponsor:
Ms. Theo Pinette and Mr. John Staehlin                        Pitney Bowes
Project Designers:                                            Contact:
Mary Wu, Nick Marchuk, Soohong Park, Justin                   Mr. John Masotta
Loffredo, Rami Subramanian                                    Project Designers:
                                                              Joe Romano, Evan Miller, James Weisheit, Alican Demir                  /
                                                                                                                            Update0 07 15
                                                                                                                              June 2
               Project HIDEF                                                   Project EZ-LIFT

               Although whiplash injuries due to rear impact colli-
               sions of automobiles are all too frequent, the exact injury
               mechanisms are not as yet understood due to a lack of
               an adequate simulation of the neck in existing crash test
               dummies. The objective of this project was to develop a
               new test dummy neck, with sufficient instrumentation to
               allow measurements of displacements and/or loads in these
               cervical spine segments (i.e., in the neck).
               JHU Applied Physics Laboratory
               Dr. Liming Voo
               Project Designers:
               Ian Wing, David Jamison IV, Joshua Chang, Alic Chan

               Project BEAST
               Baby Exercise Apparatus and Stroller
               Although there exist jogging strollers that allow one to
               have some aerobic exercise while rapidly pushing one’s baby     A common cause of back injury is due to one’s attempt-
               along, there does not now exist a means to allow one’s arms     ing to lift a too heavy object. A means to easily lift and
               to work in a comfortable motion and also provide an ad-         move such heavy items is needed, both for military and
               equate workout for the upper body while pushing a stroller.     industrial situations. An easily portable, minimum
               The team designed and built a mechanism that is part of         cost device, which can be adapted to handle a variety of
               a baby stroller, which allows one’s arms to move back and       shapes and sizes, was the objective for this project.
               forth in a significant exercise rhythm. A significant part of
               the project was the testing and market analysis.
                                                                               JHU Center for Injury Research & Policy
               BB Baby LLC                                                     Contacts:
                                                                               Ms. Sue Baker and Mr. Steven Chervak
               Ms. Krista Brick and Ms. Jill Balow                             Project Designers:
                                                                               Robert Ng, Aaron Schlotauer, Joseph Kim, Philip Kwon
               Project Designers:
               Laura Manofsky, Sam Olesky, Hubert Tseng, Evan Earnest
                                                                                Update 2007 Editorial Committee: C. Meneveau,
                                                                                (Chair), N. Cowan, and D. Santoni-Long

Mechanical Engineering                    Whiting School of Engineering
                                          223 Latrobe Hall
                                          3400 North Charles Street
                                          Baltimore, MD 21218

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