Openings for research assistants in Mechanical Engineering
August 27, 2012
The list below presents research opportunities for graduate students in Mechanical Engineering, as of
the beginning of Fall Semester 2012. In some cases, as indicated, the openings are funded and in
other cases, the openings are unfunded. Additional openings, not shown here, may become available
during the fall and spring semesters.
Prof. Alptekin Aksan (2-3 RA positions - available immediately)
Smart Reactive Bioreactive Material for Bioremediation:
We focus on developing nanoporous silica biomaterials to stably encapsulate reactive biologics
(mainly, enzymes and bacteria) to produce reactive coatings and bioreactors to be used in removing
chemicals from wastewater. The porous gel encapsulating the reactive biological enables control and
protection, while enhancing the activity of the encapsulated biological material. In very close
collaboration with the Biotechnology Institute, in an NSF-funded project we focus on developing
biomaterials to be used in bioremediation of the industrial, and agricultural wastewaters, with specific
emphasis placed on degrading the chemicals that exits in the waters used in oil and gas extraction.
Biopreservation of Human Serum:
Currently, millions of serum biospecimens are being stored in biorepositories across the nation, while
tens of thousands of new biospecimens are added to the pool daily. These biospecimens are stored for
future research, mainly for biomarker discovery and verification (e.g. for diagnostic, therapeutic, and
epidemiologic outcomes). In most biorepositories, serum is stored by freezing without following any
preservation protocol. This NIH-funded research focuses on developing the techniques to store serum
biospecimens at room temperature using isothermal vitrification technology. Isothermal vitrification
is the process by which liquids doped with sugars are desiccated to a “glass” (a very viscous fluid). In
this state, biochemical reactions are halted, degradation of the specimen is stopped, and
macromolecules are stabilized in their native states.
Note: Prof. Aksan is on sabbatical until August 2013 but is available for discussions over e-mail
(aaksan@umn.edu) and Skype. He is actively soliciting students for the RA positions available
immediately. Please contact him directly for any inquiries.
Prof. John Bischof
The bioheat and mass transfer laboratory (BHMT) at the University of Minnesota is dedicated to the
study of thermophysical and biological changes within biomaterials after thermal manipulations (esp..
heating or cooling). This work is broadly in the scientific fields of thermal biology including
cryobiology (low temperature biology) and hyperthermic biology, with particular focus in the
following application areas: (1) Nanomedicine, (2) Thermal Therapies, (3) Cryo and Biopreservation
and (4) Thermal/Mechanical Properties. The areas with support include: iron oxide and gold
nanoparticles to enhance thermal therapies. For example, iron oxide can be used for detection and
heating of cancer. In addition, gold nanoparticles can be used to deliver drugs or neo-adjuvants and to
heat cancer locally by their excitation due to electro-magnetic and optical sources. In addition,
support is anticipated in the area of microscale biomaterial thermal property estimation and predictive
modeling, a new and evolving area of biotransport research.
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Prof. Tom Chase (1 Opening)
Design of Efficient Digital Displacement Hydraulic Pump/Motors:
Digital displacement hydraulic pump/motors have the ability to effectively vary the piston
displacement stroke-by-stroke. They have potential for higher efficiency than alternative
pump/motors, particularly at low displacements. We are developing novel digital pump/motor
designs which exploit a unique valve architecture developed by our research group. This project
includes opportunities for design, modeling and control. We are particularly interested in an
application to a hydraulic hybrid passenger vehicle, also developed by our research group. This is a
joint project with Professor Perry Li.
Neutrino Detector Design and Fabrication Support:
Our group is responsible for the design of over 12,000 modules utilized in a unique 14 kiloton
neutrino detector being developed for the Fermi National Accelerator Lab. Information on the
overall experiment is available at: http://www-nova.fnal.gov. The modules will be fabricated at a
factory site staffed largely by students and located about ½ mile from campus. We are seeking a
mechanical engineering student who will support design improvements and materials testing
associated with building the modules.
Prof. Jane Davidson (1 funded opening for PhD students, 1 funded for MS)
Solar Energy Research
Prof. Davidson’s research works on solar energy technologies for both high temperature thermochemical cycles that utilize concentrated solar radiation for fuel production, and lower temperature
systems for space heating and electricity. Research on solar fuels focuses on processes to split H2O,
recycle CO2 to fuel, and gasification of biomass. Research on low temperature solar focuses on the
characterization of the fluid dynamics and heat and mass transfer of compact storage technologies.
Funding is from the National Science Foundation, the Department of Energy, and the University of
Minnesota Initiative for Renewable Energy and the Environment. We collaborate with researchers at
the National Research Energy Laboratory, Sandia National Laboratories, 3M, Caltech, and in the
Departments of Chemistry, Applied Economics, and Material Science at the University of Minnesota.
One to two funded openings in solar fuels are for experimental characterization of chemical reactors.
Prior experimental experience is preferred.
Prof. Traian Dumitrica
Thermoelectricity in Silicon Nanostructures (M.S. project 25% RA position is provided for 1
semester).
This computational project explores via microscopic modeling with the molecular dynamics method,
the thermoelectric properties of silicon nanowires. Thermoelectric materials convert temperature
differences into electricity and vice versa. Bulk silicon is a poor thermoelectric due to its large
thermal conductivity. However, silicon nanowires may have a dramatically reduced thermal
conductivity. In this project, the M.S. student will perform molecular dynamics simulations to
understand the dependence of thermal conductivity of silicon nanowires on size, temperature, and
impurity doping levels. The necessary fundamental aspects of the molecular dynamics method will be
presented in the ME8253 Computational Nanomechanics course.
Discrete Element Simulations of Hierarchically Structured Polycrystalline
Hollow Gold Nanoparticles M.S. project 25% RA position is provided for 1semester).
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This computational project is part of a larger combined experimental theoretical research program
that aims to gain fundamental understanding into the mechanics of hierarchically structured gold
nanospheres. Multiple length scales such as grain size, shell thickness, and diameter of sphere exist
within an individual structure. Specifically, our gold nanospheres are about 100 nm in diameter, and
feature a polycrystalline shell with a thickness ranging from 20 to 50 nm, and grain size around 5 nm.
Such combination provides a golden opportunity to explore the effects of structural hierarchy on the
deformation mechanisms of nanoscale materials. The M.S. student will perform simulations to
understand the mechanical response of hollow gold nanoparticles using the Discrete Element Method
in the PFC3D implementation of Itasca Co, Minneapolis. Simulations will rely on input from
experiment (in-situ TEM nanoindentation) and atomic-scale (molecular dynamics) simulations.
Training with the PFC3D software will be covered within the Itasca Education Partnership program.
Prof. Will Durfee
Medical Device Design
Muscle force assessment: System identification and clinical device development to assess the
function of healthy and diseased human muscle. Paralyzed walking: Clinical device development of a
system that combines electrical stimulation of muscle with a mechanical orthosis to restore
rudimentary walking for those paralyzed as a result of spinal cord injury. Powered orthotics:
Wearable hydraulic and pneumatic assistive devices for those with mobility impairments. Tiny
hydraulic components: Simulation and development of novel, tiny hydraulic components for human
amplifier applications. These projects have research openings, but at this time do not have additional
funding for new students.
Prof. Steven Girshick
Magnetic/Plasmonic Nanoparticles for Cancer Theranostics
The use of engineered nanoparticles opens up new and promising avenues for the diagnosis and
treatment of cancer. Tumors that are loaded with targeted nanoparticles can be destroyed by heating
the nanoparticles by either magnetic field (in the case of magnetic nanoparticles) or by laser (in the
case of nanoparticles with suitable optical absorption). In parallel, the interaction of the nanoparticles
with applied magnetic fields or laser radiation can be used to image the tumor and the heating
process. Under NSF support, an opening exists for a research assistant who will design and
implement processes for synthesizing multilayer nanoparticles, consisting of layers of
superparamagnetic iron oxide, silica, gold, and/or other materials. Synthesis methods include plasma,
UV, thermal and chemical approaches. Extensive use is made of aerosol instrumentation for
characterizing particles online, and of electron microscopy and other tools for characterizing particles
off-line. Developing control of the dimensions, morphology, chemical composition and properties of
each layer of the nanoparticle represents a major engineering challenge. This project involves
collaboration with others who study the interactions of nanoparticles with biological media.
Prof. Richard Goldstein
Several topics are available for studies of fluid mechanics and heat transfer. These include: jet
impingement flow and heat transfer, energy separation in vortex flows, heat and mass transfer
analogy studies, heat transfer related to film cooling and vortex flows in high performance gas
turbines, and buoyancy driven convection at high Rayleigh numbers. The work generally would
involve experiments with numerical analysis to predict or confirm the results. Students are expected
to be interested in pursuing a PhD.
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Prof. Jiarong Hong
Flow-structure interactions in wind power, marine and hydrokinetic power applications
This project aims at studying the interaction of turbulent flow with energy devices including mainly
wind and hydrokinetic turbines. The students are expected to design and perform experiments to
measure flow fields in the vicinity of turbine blades, and investigate the effect of turbulence
characteristics on wind or hydro energy production as well as the environment impact of these energy
devices. Students will have the opportunity to work with the-state-of-the-art research facilities at St.
Anthony Falls Laboratory, which include the 2.5 MW full-scale research wind turbine
(http://eolos.umn.edu/) and 100 m long experimental flumes operating with Mississippi River. The
experimental techniques involve particle image velocimetry, hot-wire and ultrasonic anemometry.
Students are encouraged to develop new experimental tools to accomplish the measurements.
Turbulent flow field over complex, biomimetic surfaces
This project will investigate the behaviors of turbulence over surfaces with some interesting
biomimetic topography, e.g. the surfaces that replicate shark skin denticles and deformable roughness
that mimic marine vegetations. Optical-based experimental approach will be applied to measure the
detailed flow fields neighboring the surface. We will study how the turbulence structures are
modified by these surface protrusions to achieve certain hydrodynamic functions. In order to reduce
the optical scattering at the fluid-solid interface that contaminant the near-wall flow measurement, the
experiment will operate with a fluid that matches optical refractive index of the surface. The students
are expected to take part in the designing of such facility, overcome the difficulty of near-wall flow
measurement and carry out in-depth data analysis.
For both projects, students are expected to be interested in pursuing a PhD. Please feel free to contact
Prof. Hong at jhong@umn.edu for more information.
Prof. David Kittelson
Advanced Engine Combustion and Fuels
We are seeking students to work on projects focusing on advanced engine cycles and fuels. In recent
years a variety of new engine combustion paths have been developed that involve low temperature
combustion, largely avoiding soot and NOx formation but maintaining high thermodynamic
efficiency. While these approaches offer great promise there are still many challenges including;
difficulty controlling the start of combustion, poor transient behavior, and limited range of operation.
We are working a new type of low temperature combustion called reaction controlled compression
ignition (RCCI) that has the potential of overcoming many of these problems. RCCI is also well
suited for combustion of biofuels and we are currently exploring such fuels as ethanol, biogas, and
gas produced by biomass gasification. We are also researching alternatives to diesel fuel derived from
biomass. These include biodiesel, vegetable oils, butanol, and di-methyl ether (DME). DME is
particularly interesting because it can be made from various biomass feed-stocks including municipal
waste, grasses, crop and forestry residues, algae, and black liquor. On the other hand, DME can't be
run in current diesel engines without significant fuel system modifications. We are working on
characterizing performance and emissions of DME fueled engines at the same time as we develop
new fuel system components. Students working on these projects should be interested in
thermodynamics and combustion, data acquisition and processing, sensors, and have good hands-on
skills.
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Improving Energy Efficiency of Urban Buses
Reducing emissions from transportation is a function of reducing vehicle miles traveled, fuel carbon
content, and increasing fuel efficiency, and these parameters are influenced by engineering practice.
Our research will focus on improving bus fuel efficiency through the electrification of “hotel loads”
(accessories such as heating, cooling, fans, etc.). We will quantify the cost savings and estimate the
emissions reduction of such improvements. Previous we completed a small project that was jointly
funded by the Center for Transportation Study (CTS), Metro Transit and IREE. We found that hotel
load electrification could improve fuel efficiency by more than 10%, but our data were limited, and
the cost of bus conversion was not well quantified. Our research goal is to quantify the real-world, inuse hotel load power consumption for three types of buses including a standard diesel bus, a parallel
hybrid bus and a fully electrified series hybrid bus, and make recommendations on specific bus
configurations, estimate conversion cost, and GHG emissions. We expect that hotel load
electrification will achieve significant improvements in fuel economy improvement at far less cost
than the purchase of new, hybrid bus technology. Students working on this project should be
interested in transportation, data acquisition, management, and processing, sensors, and have good
computer and data management skills.
Prof. Barney Klamecki (2 funded openings: 1 PhD, 1 MS)
Removal of Plaque from Arteries by Machining
This is a collaborative project involving the University of Minnesota, the University of Michigan and
a Twin Cities-based medical device manufacturer. The general project topic is the machining of
biological tissue. The specific application area is machining for removal of plaque from arteries. The
research will span from developing basic mechanics of machining of tissue, to describing the
dynamics of a cutting tool at the end of a long drive wire, to the characterizing deformation and
possible damage to the artery wall, to monitoring the material removal process in the artery. The
primary work to be done at the University of Minnesota includes formulating and constructing
numerical and physical experiments to characterize the deformation of the soft tissue supporting the
plaque that is being machined and to describe the behavior of a long, flexible drive wire operating in
a confined, fluid-filled space approximating machining plaque in an artery. Research will also include
developing a sensing system for deducing the type of material being machined.
Prof. Uwe Kortshagen (1-2 openings)
Nanomaterials for Renewable Energy
Professor Kortshagen's group is interested in exploring new nanoscale materials in the area of
renewable energy. His group has developed a novel plasma synthesis approach to produce
nanometer-sized semiconductor particles. This technology has been licensed by major multi-national
corporations and is currently being employed by several solar cell manufacturers.
Professor Kortshagen has research openings in a new project involving plasmonic properties of
nanocrystals. In this project, the oscillation of free electrons in a semiconductor will be used to
actively tune the absorption properties of the nanomaterial. The possibility to tailor the optical
properties of nanocrystals may be of significant benefit to photovoltaic applications, light emitting
devices, and defense related technologies.
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Prof. Perry Li (1-3 Openings)
Hydraulic Transformers
The intension for hydraulic transformer is similar to that of an electric transformer – to transform
power at one pressure/flow rate (voltage/current) to another. This is a potentially efficient approach
for distributing and controlling hydraulic power. This will find applications in hydraulic actuated
machines, such as all kinds of robots, construction equipment, hydraulic hybrid vehicles etc. Yet,
hydraulic transformers are not generally available. This research aims to gain fundamental
understanding of configuration, dynamics and control, so as to guide in their designs, and to
demonstrate their potential in an interesting application. One additional RA position may be available
for a highly motivated, qualified student interested in the intersection of controls, dynamics, machine
design and robotic actuation. A PhD student is preferred. This project is funded by the Center for
Compact and Efficient Fluid Power.
Design of Efficient Digital Displacement Hydraulic Pump/Motors.
Hydraulic pump/motors are critical for many emerging applications such as wind turbines and
hydraulic hybrid vehicles, as well as established applications such as mobile construction equipment,
injection molding machines and material testing. Using current means of varying displacements,
hydraulic pump/motors are not very energy efficient at partial or low displacements. Digital
displacements, or the use of on/off valves to control displacements, can potentially maintain high
efficiencies at all displacements. An RA is sought to work on hydraulic and mechanical design of
such a digital displacement pump/motor. This project is funded by the NSF Center for Compact and
Efficient Fluid Power. (Joint project with Prof. Tom Chase)
Compressed Air Energy Storage for Off-Shore Wind Turbines.
This is a NSF funded multi-university/industry collaborative project that involves developing a novel
approach for storing excess wind energy using compressed air vessels. This will make wind power
more available and alleviate our dependence on fossil fuels. At the University of Minnesota, we are
responsible for the overall systems architecture and design; as well as the fundamental research in
heat transfer to achieve near isothermal compression and expansion. This project is highly
interdisciplinary and involves fluid flow, fluid power, heat transfer, machine design and system
dynamics and controls. A possible RA position exists for an exceptional PhD candidate to focus on
either the heat transfer and system/integration aspect of the project. Successful candidates will have
opportunities to do analytical and experimental work, as well as to work with teams at other sites and
to develop multi-disciplinary skills.
Prof. Wojciech Lipinski: Thermochemical sciences, solar power and fuels
Radiative heat transfer in chemically reacting media for high-temperature solar thermo-chemical
cycles (unfunded)
Numerical and experimental techniques are employed to study radiative transfer and properties of
materials encountered in novel solar thermochemical cycles for renewable fuel production and CO2
capture. The radiative models and properties are employed in combined heat and mass transfer
simulations of chemically reacting media to predict their temperatures and composition as a function
of time.
Radiative heat transfer in micro- and nanomaterials for solar energy conversion (unfunded)
Multi-scale radiative heat transfer is analyzed for novel materials featuring ordered and/or random
nano- and micro-structures that are encountered in solar energy conversion processes. Exact
morphology of the materials is determined by sub-micron computed tomography techniques, and
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used in electromagnetic solvers to obtain continuum optical and radiative properties.
Thermodynamic and heat transfer analyses of a solar tower power plant using molten salt storage for
24-hour electricity generation (unfunded)
Thermodynamic and heat transfer analyses are performed for a solar tower power plant with a molten
salt high-temperature heat storage for continuous 24-hour electricity generation.
Prof. Will Northrop
The Center for Diesel Research (CDR) is a leader in research focusing on the nexus of emissions,
alternative fuels, and advanced combustion in internal combustion engines. Opportunities exist for
motivated students with experience in experimental work and enthusiasm for thermal sciences.
Current openings include:
In-cylinder temperature measurement using ultrasonic thermometry (unfunded)
Currently, high speed, and spatially-resolved measurement of in-cylinder temperature in internal
combustion engines is not possible without significant engine modification and the use of expensive
optical diagnostic equipment. Building on a bio-analog to the navigation system of bats, the use of
ultrasound as a minimally invasive temperature diagnostic in engines is a promising technique. A
student is desired to work on developing a National Instruments-based data acquisition system for
measuring temperature in a reciprocating engine using ultrasonic transducers. Applicants with strong
skills in LabVIEW are preferred. Knowledge in acoustics is also a plus for this challenging project.
Exhaust gas recycle (EGR) cooler fouling in diesel engines (RA, 1.5 years)
Exhaust gas recirculation (EGR) is extensively used in non-road diesel engines in concert with
common-rail direct-injection (CIDI) and turbocharging, to meet stringent EPA Tier 4 Final emissions
requirements. Extensive use of EGR in new diesel engines presents new challenges as the heat
exchanger required to cool the exhaust before mixing with the intake gas can be fouled by a mixture
of carbonaceous soot and semi-volatile hydrocarbons. For applications with long service intervals,
EGR cooler fouling represents a significant challenge. A student is needed to conduct a study in
cooperation with a local industrial partner to characterize the rate of EGR cooler fouling and to build
on current knowledge in fouling processes. The project will involve the use of specialized particle
and gas measurement instruments.
Prof. David Pui
Center for Filtration Research (CFR)
CFR is funded by twelve filter companies and end users: 3M, Boeing, Cummins, Donaldson,
Entergris, W.L. Gore, Hollingsworth & Vose, Mann+Hummel (Germany), MSP Corp, Shigematsu
(Japan), Samsung (Korea), and TSI Inc. The objectives are to foster industry/university collaboration
in filtration and to help University to become more relevant in its research and education. We
perform fundamental filtration research and theoretical modeling; develop improved experimental
methods useful for filtration research, filter characterization and filter testing; and to seek new
applications of scientific knowledge to practical filtration problems.
Prof. Rajesh Rajamani
The research program in Prof. Rajamani’s laboratory focuses on the development of novel sensors
and control systems for automotive and biomedical applications. The sensors and control systems
developed in our lab often serve as enabling technologies that make important new mechanical
devices and systems possible. Examples of new systems under development include ultra-small
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muscle sensors for quantification of neuromuscular diseases, tactile micro-sensors for minimally
invasive medical applications, tire sensors for measurement of slip angle, slip ratio and tire-road
friction coefficient and battery-less wireless sensors for traffic flow measurements. To find out more
about our research projects, please visit our web site:
http://www.me.umn.edu/labs/advcontrols/index.html
One research opening is available in Fall 2012 in the area of biosensors.
Prof. Terrence Simon (1 opening)
Forced Unsteady Heat Transfer
We are developing a new technology for energy conversion. It uses an alloy that passes through
phase transformation, changing its magnetic properties with changing temperature. During
transformation, latent heat is absorbed and electricity is produced by induction without a separate
electrical generator. A major challenge is rapidly oscillating the temperature back and forth through
the transformation temperature at near ambient temperatures. Ideas to be pursued include shuttered
radiate heating, oscillating heat pipes and intermittent cooling with thin-film evaporation of liquid
droplets, An additional challenge is integration of the heat transfer system into the remainder of the
power generation system. Coincident with this development, and parts of the same program, will be
activities in the AEM and CEMS Departments developing and improving upon the alloys. It is a
project sponsored by the Department of Energy.
Prof. Eph Sparrow (4 openings)
LABORATORY FOR ENGINEERING PRACTICE (LEP)
LEP works on any and all problems within and on the edges of mechanical engineering. Since LEP
does not depend on external funding, everyone in the group is free to work on whatever she/he
wishes and to fulfill their personal objectives in whatever way they wish. Problems are attacked by
two complementary powerful tools: laboratory experiment and numerical simulation. The lab is very
well equipped, and the simulation software is at the cutting edge. DESIGN is a common
denominator.
LEP is the happy recipient of a wide variety of real-world projects from local industry. These
projects represent a unique learning experience. Currently, there are projects in Biomedical
Engineering, Electronics, Solar Photovoltaics, Wind Engineering, Geothermal Heat Transfer,
Structures, Materials Processing, Particle Transport, and Cryogenics. Anyone is free to work on any
project depending on what she/he wishes to learn. Help is always available at all hours. LEP is a
family, where giving, sharing, and mutual respect prevail. LEP has especially enjoyed working with
physics majors from liberal arts colleges and with persons employed in industry.
Prof. Zongxuan Sun
Control Oriented Model for Advanced Engines
The research objective is to develop accurate yet tractable dynamic models for SI (Spark Ignited) and
HCCI (Homogeneous Charge Compression Ignition) dual mode engines to enable model-based realtime control and optimization of this novel and efficient internal combustion engine. Increasing
concerns about global warming and ever-increasing demands on fossil fuel capacity call for reduced
emissions and improved fuel efficiency. Homogeneous Charge Compression Ignition (HCCI) engine
that blends characteristics of spark ignition (SI) and compression ignition (CI) engines has been
proposed as a promising solution. Like the SI engine, a homogeneous air and fuel mixture is drawn
into the cylinder during the intake stroke. There is no spark and the mixture temperature and pressure
are increased during the compression stroke (like a CI engine) for auto-ignition. Since the start of
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combustion depends on the dynamic conditions of the in-cylinder mixture, precise control of the
mixture states in real-time is necessary. This requires an accurate model that captures the dynamic
behavior and interactions of fuel, air, and other combustion products (charge mixing). Specifically,
we are developing a control oriented charge mixing model to capture the fluid dynamics and
chemical composition of the engine. This charge mixing model will be first validated with CFD
simulation and then with experiments. Finally the mixing model will be integrated with a hybrid
combustion model developed by our collaborator. Interested student should send a detailed resume to
Prof. Sun at zsun@umn.edu.
Prof. James Van de Ven
Soft Switching for Digital Hydraulics
(50% RA position)
An emerging method to control hydraulic circuits is digital hydraulics, where a high-speed valve is
used to switch a circuit between efficient on and off states, theoretically improving efficiency. At
high switching frequencies, the transitional throttling and hydraulic fluid compressibility become
important sources of energy loss. A novel approach to minimize this loss is to absorb or redirect the
flow during the valve transition events in a “soft switch.” This project involves the construction of a
dynamic model of a digital hydraulic circuit, design and optimization of a soft switch mechanism,
and experimental work to validate the model and test the design solution.
Energy Storage in Hydraulic Systems
Hydraulic power transmission has an order of magnitude higher power density than competing
technologies, yet suffers from poor energy storage density. The energy storage issue is being
addressed through a flywheel-accumulator, which integrates pneumatic and rotating kinetic energy
storage, and compressed air energy storage. Exceptional students with interests in machine design
and fluid dynamics will be considered for inclusion in one or both of these research projects.
Liquid Piston Stirling Cycle Engine Parameter Space Exploration:
(50% RA position for 1 semester)
A liquid piston Stirling cycle engine has the potential for good efficiency and high power density by
isothermalizing the compression and expansion of the working gas and eliminating the volume
associated with conventional hot and cold heat exchangers. In this project, a guided parametric study
will be performed to determine areas in the parameter space that will maximize the efficiency and
power density. These parameters will then be used to design optimal liquid piston
compressor/expanders.
Prof. Rusen Yang
Energy harvesting with nanostructures
Piezoelectric nanomaterials will be thoroughly investigated. Energy harvester will be fabricated to
convert the mechanical energy into electricity. A better understanding of the working principle as
well as a better design will significantly improve the performance of the energy harvester. A large
scale fabrication of the device will result in practical application in various fields. The technique
involved in this project will include the atomic force microscopy (AFM), photo lithography, e-beam
lithography, focused ion beam (FIB), as well as electric and mechanic property characterization.
Tactile sensing with nanomaterials
When a material with both piezoelectric and semiconducting property, such as zinc oxide, is stressed,
the electrical potential generated due to the stress (piezopotential) can effectively change the band
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structure at the heterojunction interface and result in significant changes in the electronic transport
property. This phenomenon is promising for designing novel devices, including tactile sensors to
replicate the human finger tactile perception capabilities. This research offers exciting possibilities
for applications in robotics, teleoperation, manufacturing, mechatronic devices and minimally
invasive surgery.
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