Current Projects

• Studies to be conducted under higher in-cylinder flows with tumble planks installed in the intake port
• Studies of alternative geometry plugs
• Studies of plug orientation and gap
• Chemiluminescent imaging for combustion signature

Confidential

1. A method for obtaining instantaneous wave surface elevation information on a wave-by wave basis using a low-cost X-band Radar (the state of the art, as represented by the commercially available WaMOS system is optimized to provide spectral information.
2. A method for providing constrained near-optimal wave-by-wave control for maximizing the energy conversion by small wave energy converters.
3. Although the focus of the proposed research is wave energy converter technology, the results of this work are expected to find application in other forthcoming Navy developments. Wave-by-wave surface elevation prediction and near-optimal power absorption techniques demonstrated in this effort can be extended to facilitate critical mid-sea shipboard operations such as helicopter/ aircraft landing, cargo handling, etc. The techniques demonstrated as part of this research will also provide technology to enhance and optimize seakeeping characteristics of Navy ocean platforms.

The objective of this project is to develop the combustion system for a low-cost, low diesel contribution, high brake mean effective pressure (BMEP), high-efficiency premixed charge medium/heavy duty (MHD) natural gas engine and demonstrate the technology on an engine with peak thermal efficiency of up to 44%, diesel pilot contribution of 1-5%, and BMEP up to 25 bar. Emissions will be compliant with current Environmental Protection Agency (EPA) standards for heavy-duty (HD) on-road engines by using a three-way catalyst.

This project encompasses three separate projects that are a part of a NSF I/UCRC that is centered at the University of Denver. The three projects are:

• B3: Physical and Chemical Aging of Carbon/Epoxy Composites

• Cl: Development of Advanced Aluminum Alloys for High Conductivity, Elevated Temperature Strength, and Low Galanic Corrosion

• C2: Thermo-Mechanical-Electrical Properties of Carbon Fiber /Nanoparticle/Epoxy Composites

Project Goal of B3

This project has three objectives: (1) Develop simple and accurate structure­ property relationships relating exposure conditions and nanoparticle content to expected thermo-mechanical performance; (2) Fabricate, characterize, and test polymer and polymer composite materials exposed to long durations of sub-Tg and elevated temperatures, moisture, UV radiation, and oxidative environments; and (3) Use molecular modeling techniques to provide physical insight into observed behavior.

Project Goal of C1

Potential aluminum alloys will be identified and examined for their conductivity through Vienna Ab-initio-Simulation Package (VASP) Density Functional Theory (DFT). Precipitation kinetics will be simulated with Prisma using the MOBA13 database. Using VASP DFT calculations and ThermoCalc, a computational survey will be utilized to select promising alloy compositions and heat treatments. Once this computational survey has been performed, select alloys will be fabricated and assessed experimentally for conductivity and hardness amongst other properties.

Project Goal of C2

This project has two objectives: (1) Develop molecular models to efficiently determine nanoparticle/epoxy combinations that enhance stress & heat transfer and (2) Fabricate and test graphite fiber/nanoparticle/epoxy hybrid composite panels for thermal conductivity, impact & compression strength, and electrical conductivity and shielding

Overview:

Success of numerous long-term robotic network missions in space, air, ground, and water is measured by the ability of the robots to operate for extended time in highly dynamic and potentially hazardous operating environments. The proposed work responds to the urgency for development of innovative mobile power distribution systems that lower deployment and operating costs, while simultaneously increasing mission efficiency, and supporting the network's need to be responsive to changing physical conditions. The overall CAREER goal is to develop a power distribution system that responds to individual robot needs, as well as, overall robotic network goals to guarantee persistence of long-term operation in uncertain and unstructured environments.

The proposed work is informed by the hypothesis that network persistence hinges on the ability to establish stable energy transfer cycles necessary to accomplish coverage specifications, while simultaneously dealing with physical and environmental constraints. To test this hypothesis and as an example of such a system, this work will focus on creating a reliable autonomous recharging system for autonomous underwater vehicles (AUVs) that enables continuous real-time marine observation and data collection in the presence of continuously changing underwater environmental circumstances. The key challenges are two-fold: there are fundamental hardware challenges connected to energy transfer in the harsh underwater environment, but more importantly there are basic network science needs that are novel to a mobile power network. The specific research thrusts for this CAREER work include: 1) Task and Energy Routing Scheduling for Persistent Mission Planning. 2) Efficient Network Path Planning and Coordination to Accomplish Persistent Mission Plan. 3) Experimental Validation through Test-bed Development. 4) Design-based, Research-integrated Education Plan for Broadening Underrepresented Participation in STEM.

Intellectual Merit:

This project builds a roadmap to achieve robust continuous marine autonomy that advances unmanned marine systems ability to perform autonomous long-term missions. More specifically the proposed work will provide: 1) resource based task scheduling, 2) path planning formation for mission and charging, and 3) integration tools for testing. Expected outcomes will overcome the current challenge of significant interruptions during underwater missions due to battery limitations and recharging needs. Through this CAREER proposal, the Pl will establish the theoretical, computational, and experimental foundation for mobile power delivery and onsite recharging capability for autonomous underwater vehicles (AUVs). The developed power distribution system will be able to reconfigure itself depending on the scope of the mission, as well as, the energy consumption needs of the network, the number of operational AUVs and required operation time, recharging specifications, communication and localization means, and environmental variables.

Such a system will play a vital role in real-time controlled applications across multiple disciplines, such as: sensor networks, robotics, and transportation systems where limited power resources and unknown environmental dynamics pose major constraints. All developed tools will be suited for the capabilities of not only low-cost AUVs with limited sensing and computational resources, but also high-tech AUVs with state of the art sensor packages.

Broader Impacts:

The developed active power distribution system focuses on underwater scenarios, but will be transferrable to space, air, and ground missions as well. This type of feasible power distribution solution can be used to optimize: 1) immediate high-risk disaster recovery missions like the Fukushima nuclear plant accident; 2) search missions that require vast underwater inspection and detection like the Malaysia MH370 passenger aircraft; and 3) long-term space observation and monitoring like that of the lunar skylight or Europa space mission. The findings from this project will be disseminated through publications, software sharing, and technology commercialization. The project provides interdisciplinary training opportunities for graduate, undergraduate, and pre-college students, including those from underrepresented groups. Research activities will be integrated with education through curriculum development, outreach and improved GUPPIE design.

Overview:

Design optimization of cyber-physical systems (CPS) includes optimizing the system architecture (topology) in addition to the system variables. Optimizing the system architecture renders the dimension of the design space variable (the number of design variables to be optimized is a variable.) This class of Variable-Size Design Space (VSDS) optimization problems arises in many CPS applications including (1) microgrid design, (2) automated construction, (2) optimal grouping, and (3) space mission design optimization.

Evolutionary Algorithms (EAs) present a paradigm for statistical inference that implements a simplified computational model of the mechanisms embedded in natural evolution, with potential to solve this problem. However, existing EAs cannot optimize among solutions of different architectures because of the inherent strategy for coding the variables in EAs. Existing EAs resembles natural evolution in which a given architecture can evolve by improving the state of its variables but cannot be revolutionized. Inspired by the concept of hidden genes in biology, this project investigates revolutionary optimization algorithms that can optimize among different solution architectures and autonomously develop new architectures that might not be known a priori, yet are more fit solution architectures. Efficacy of the new algorithms for CPS is evaluated in the context of space mission design optimization.

Intellectual Merit:

There is an increasing demand in the scientific community for autonomous design optimization tools that can revolutionize systems designs and capabilities. Most existing optimization algorithms can only search for optimal solutions in a fixed-size design space; and hence they cannot be used for solution architecture optimization. Few existing algorithms can search for optimal solutions in VSDS problems; however these are problem-specific algorithms and cannot be used as a general framework for VSDS optimization. This project investigates the novel concept of hidden genes in coding the variables in evolutionary algorithms so that the resulting algorithms can be used for optimizing VSDS problems. The key innovation in these new algorithms is the new coding strategies. In addition, in this project, the standard operations in EAs will be replaced by new operations that are defined to enable revolutionizing a current population of solution architectures using the new coding strategy. The Pl's recent research results, in the context of space mission design optimization, demonstrate that the hidden genes optimization algorithms can search for optimal solutions among different solution architectures, revolutionize an initial population of solutions, and construct new solution architectures that are more fit than the initial population solutions.

Overview:

Correctly, the 2009 Roadmap for US Robotics report predicted that robotics technology would transform the future of the US workforce and households. From Roomba vacuum cleaners to Wii video games, we increasingly see robotic technology in work spaces and homes. Yet, the US continues to lag behind China, South Korea, Japan, and European Union in its investment in robotics research and education. The Next Generation Science Standards for Today's Students and Tomorrow's Workforce responds to this critical need by providing a curricular framework for using crosscutting concepts and disciplinary ideas that: have broad importance across science and engineering disciplines; are taught around a key organizing concept (like health or water) and use key tool (pedagogical platform); have a significant context for students and are explicitly connected to societal needs; and are teachable and learnable over multiple grades. Informed by this framework, our proposed NRI aims to develop, test, and assess two co-robotic platforms with high impact potential and longevity as a pedagogical platform (use is applicable from 4th grade through graduate school learning). Two unique robotics educational platforms will be used to teach 6th-8th grade: an educational underwater glider called GUPPIE and a surface electromyography (sEMG)- controlled manipulator called Neu-pulator. Both of these platforms can be categorized as co-robot and cost less than $1000. GUPPIE is an unmanned vehicle that has application in monitoring and inspection of the environment and can be used to introduce students to the application of robots as co-explorers in everyday life. Neu-pulator is a human-interactive robot that uses electrical activity of human muscles to move a manipulator. It introduces students to assistive robots, which are a class of co-robots that aim to amplify or compensate for human capabilities. We hypothesize that meaningful contexts and hands-on learning with co-robotic platforms will broaden impact to diverse audiences and increase interest in critical STEM areas. The overall goal of the proposed NRI is to develop and evaluate the use of co-robotic platforms in learning contexts that are socially meaningful, especially for underrepresented students (female students from rural, low socioeconomic areas in the Upper Peninsula of Michigan). Our specific objectives are to: 1) Optimize Michigan Tech's co-robotic platform designs for teaching STEM concepts. 2) Develop educational activities/curriculum utilizing Michigan Tech's co-robotic platforms. 3) Investigate the co-robotic platforms effectiveness in engaging students in STEM learning.

Intellectual Merit:

The proposed work will develop a pedagogical platform and evaluation method that can be easily translated for classroom practice from grades 4th-12th and in undergraduate to graduate degree programs. Training teachers in platform use during teacher workshops will help schools respond to and integrate new science standards - efficiently and effectively using meaningful contexts. Continued online training and modules will be available to broadly disseminate platform applications for informal and formal learning contexts. The hardware development and programming of co-robots will teach critical analytical thinking. The nature of co-robotic platforms, on the other hand, will inspire students to become integrative designers. By exercising both analytical thinking and design skills, these co-robotic platforms will improve students' ability for creative problem solving, and ultimately increase individual motivation for pursuing STEM academic and career pathways. The project will produce research that compares the effectiveness of mission-based and application-based robotics activities for engaging students in STEM.

Abstract

For shear driven flows, a comparison of the traditional boiler and condenser operations with those of the proposed innovative boiler and condenser operations. The innovative devices are introduced for functionality and high heat capability for shear dominated situations that arise in milli-meter scale operations, certain gravityinsensitive operations (on aircrafts), and zero-gravity operations. These devices therefore facilitate the development of thermal management applications which employ boilers and condensers under these conditions. The operational methodologies that exploit ways to significantly enhance heat-flux (e.g. > 1 kW/cm2) within the context of the proposed operations are also presented. These benefits are realized at acceptably low mass-fluxes, pressure drops, and inlet temperatures close to saturation temperatures (i.e. without subcooling requirements).

The experimental realizations for innovative devices are reported for flows within horizontal channels. Results for these flows of FC-72 vapor in a horizontal rectangular cross-section duct (2 or 6 mm gap and 15 mm width) of 1 m length. The experiments demonstrate the ability to restrict the boiling and condensing flows to annular flows where a thin film flows (< 0.5 mm) over the entire heat exchange surface of the device.

Introduction and utilization of controlled pulsations (in 5-20 Hz range) in the mass flow rate show an ability to maintain thin film flows with significant additional enhancements ( >300 %) in heat-transfer rates over those obtained in the absence of controlled pulsations. The reported enhancements are associated with asymmetric reduction in the timeaveraged mean film thickness (associated with high heat-flux values) appears to be related to the larger “dwell” time (relative to the characteristic time period of the pulsation) of wave-troughs when the instantaneous film thicknesses (at the wave troughs) become less than tens of micro-meters. The demands of this “dwelling/sticking” nature of micro-scale flows on top of a wetting heat-exchange surface are believed to be met by interactions with (and destabilization of) the adjacent solid-like adsorbed layer (whose thickness may be <200 nm) on the heat-exchange surface. The presence of adsorbed layer under these conditions (three phases being close to one another) allows for the presence of phenomena that govern film dynamics – e.g. a range of positive to negative disjoining pressures and the ability to withstand shear stresses. In nucleate pool boiling, similar phenomena (very high heat-flux values) under similar conditions are known to be present at the contact line of growing and departing bubbles.

Abstract

Overview: Apoferritin is an organic cage that captures the toxic free ferrous ions and transforms them into a ferrihydrite and iron oxide crystalline nanoparticle through a complex biomineralization process (the resulting structural protein is called ferritin). Any dysfunction of ferritin protein can result in iron toxicity, serious illness, chronic diseases, and especially neurological diseases. Dysfunction in ferritin results in the alterations in the biomineralization of the ferritin cores, and therefore, understanding the process of biomineralization within ferritin, is of great importance in the study of neurodegeneration and other chronic diseases. While these unique proteins have been the subject of intense research in biology and chemistry fields due to their importance in many chronic diseases, little effort has been made to unveil the dynamics of such biomineralization processes in liquid conditions. To the Pl's knowledge, there has been no direct evidence at atomic level on how the biomineralization or demineralization inside a ferritin protein progresses over time. This research aims to fill this gap.

The objective of this project is to investigate the in situ crystallization of ferrous ions into crystalline ferrihydrite and iron oxide nanoparticles as well as the demineralization of crystalline core in healthy and dysfunction ferritins in unprecedented resolutions within liquids. In-situ studies conducted inside an atomic resolution aberration-corrected scanning transmission electron microscope (STEM) enabling imaging at resolutions better than 1A. A miniaturized graphene-based electron transparent bio/nano reactor compatible with the microscope chamber is utilized to preserve the liquid environment inside the electron microscope. In this graphene bio/nano reactor, ferrous ions delivered to apoferritins through break down of liposomes acting as reservoirs of irons to trigger the biomineralization within apoferritins cores.

The research is the first atomic resolution study of proteinmediated biomineralization and demineralization within a liquid media and inside a transmission electron microscope. This CAREER research unfolds: (I) The nucleation and growth mechanisms of mineral core (ferrihydrite and iron oxide crystals), (II) the existence and evolution of atomic defects (vacancy, twinning, misorientation boundaries, amorphous regions, etc) during the crystallization, (Ill) the evolution of chemical gradient from surface to core of crystals during the biomineralization, (IV) the mechanisms of demineralization due to iron release, and (V) The atomic-scale morphological and structural differences between a healthy and dysfunctional ferritins.

This research probes the ground rules for ferritin biomineralization with the goal to unveil the fundamental differences with dysfunctional ferritins responsible for neurological diseases. In addition, a new research field for the utilization of bio/nano reactors to image complex biochemical reactions at atomic resolutions will be developed. The CAREER plan will impact the society by integrating multi-disciplinary research with education at all levels while promoting diversity. Graduate and undergraduate students involved with the project will be trained in cross-cutting areas.

MTU Consortium in Diesel Engine Aftertreatment Research

Starting from a well-established research program and as a result of a Dept. of Energy 3 year project, we have significantly enhanced our laboratory, experimental methods and procedures, and modeling/estimator capability. The faculty and students have produced thirteen publications from this research.

Consortium Goal:

The underling goal of the consortium is to develop and conduct precompetitive research on advanced aftertreatment systems through experimental engine methods, development and calibration of high fidelity models, and development and application of estimators and controllers. Achieving this goal will provide an improved understanding of the systems under dynamic and low temperature conditions characteristic of advanced medium and heavy duty diesel engines allowing the consortium members to apply this knowledge and models to improve system performance, reduce cost, and develop new approaches to diagnostics and increase robustness of their on-board-diagnostics.

Research Activities:

The existing facilities and an extensive model base will be used as developed in previous research including the current DOE program. This includes temperature controlled exhaust, positive torque drive cycles, and validated component models and estimators. Additionally we will add real-time functionality to perform aftertreatment estimation and control in the engine test cell.

The consortium research themes integrate fundamental and applied aspects of (1) Experimental Engine Studies (2) Modeling and Simulation and (3) Estimation, Control, and diagnostics. The proposed research is split into three major themes (I) Experimental, (II) Modeling, and (III) Estimation and Controls with a number of outcomes from the composite research program.

Areas of study will be determined based upon proposed research by MTU with input from the Partners to direct the research.

Based upon input from our partners and continuing some efforts from the DOE program, the following have been identified as key areas from which yearly research topics will be selected.

• Experimentally validated reduced order models and state estimation algorithms of aftertreatment components which are accurate for low temperature and dynamic operation.
• Quantify particulate matter (PM) maldistribution, loading, and NO2/PM ratio effects on passive and active regeneration, bio-fuel blends, and aging for catalyzed particulate filters (CPFs).
• Increased knowledge of ammonia (NH3) storage behavior, optimal NH3 loading, hydrocarbon (HC) poisoning, and aging for selective catalytic reduction (SCR) catalysts
• Understanding effect of sensor type/configuration on state estimation quality.
• Optimal reductant strategies for SCR operation and CPF regeneration.
• Integrated response and optimization of engine feedgas and aftertreatment systems
• Thermal control of the aftertreatment components for light-off, maintaining operational temperature, and regeneration relevant to engine low temperature operation and integration with exhaust energy recovery systems
• Fundamental studies of DEF introduction and functional responses – hydrolysis and pyrolysis
• Diagnostic concept development: Based upon existing virtual sensor and estimator work this will be translated into system and component diagnostics
• Sensor displacement by applying estimators and virtual sensors. For example, determining whether a NH ₃ sensor is needed if an accurate SCR NH ₃ storage model is available.
• Improved DPF PM estimation and measurement. Although systems are going to increase passive oxidation with engines moving to higher NO _X and lower PM, this is still an important research area to improve methods to accurately estimate CPF loading.
• Alternative and integrated aftertreatment technologies such as integrated SCR with PM filtration. Many fundamental questions remain about this technology including architecture of combining functions that still enable high passive PM oxidation and high NO _X conversion.
• PM Sampling and related diagnostic use. Quantifying the effect of sensor location on the ability to detect failures. does it matter where the sensor is and what the type of failure is. e.g. For example, how does the location of the PM sensor impact the speed of CPF melt down detection and can this speed of detection be optimized?

Overview:

Mobility is a key factor to well-being, both emotionally (through increased independence and decreased depression and anxiety) and physically {through reduced disease risk, bone maintenance, muscle strength, and weight control). Over a million US citizens are limb amputees, primarily lower leg amputees. This program will 1) work to improve the mobility of lower extremity amputees through research in design and control of powered ankle-foot prostheses, which mimic the steering mechanism of human gait by having two controllable degrees of freedom (DOF) and 2) integrate research with education and outreach to inspire and equip a diverse next generation of engineers. To work toward these long-term goals, this program will develop – and use in education and outreach - a lightweight, cable-driven, powered ankle-foot prosthesis capable of steering and traversing slopes by learning from human ankle impedance in the sagittal and frontal planes during gait.

This research is based on the hypothesis that an ankle-foot prosthesis capable of applying torques and impedance modulation in both the sagittal and frontal planes, similar to the human ankle, will improve maneuverability and increase mobility by lowering the metabolic cost of gait - both when walking straight and turning. Advances in powered prostheses have shown the ability to reduce metabolic cost and increase the preferred speed of gait for unilateral transtibial amputees during straight walking by providing sufficient power during push-off. Powered prostheses can also reduce asymmetrical gait patterns and thus may lower risk of secondary complications. However, studies show that turning steps account for 8-50% of steps, depending on activity, and thus may account for 25% of daily steps. Modulation of ankle impedance in the sagittal and frontal planes plays a major role in controlling lateral and propulsive ground reaction forces. While a non-amputee relies on hip movement in the coronal plane and the moment generated in the ankle joint, an amputee using a passive prosthesis uses the hip extension in the sagittal plane as a gait strategy. The hypothesis is supported by preliminary results which show a large inversion of the ankle during the stance period of step turns, indicating a significant deviation of ankle rotations from the straight-step pattern.

Understanding the role of the ankle in locomotion and developing a platform for design and control of new ankle-foot prostheses will allow exploratory research and education. Research includes: Thrust 1: Estimate ankle impedance in the sagittal and frontal planes during the stance period of gait; Thrust 2: Develop a powered ankle-foot prosthesis with two controllable DOF; Thrust 3: Evaluate the design and control of the prosthesis using an evaluation platform and with below-knee amputees through collaboration with Mayo Clinic; and Thrust 4: Education/Outreach: Utilize the steerable ankle-foot prosthesis for education, outreach, and research experiences to impact diverse K-12, community college, undergraduate, and graduate students.

The work is significant in that it will contribute 1) new knowledge about multivariable impedance modulation of the human ankle during the stance period of gait, an area not yet fully explored, and 2) a unique framework for developing and evaluating powered ankle-foot prostheses. The steerable ankle-foot prosthesis is innovative because it will enable amputees to walk with a more natural gait by using the ankle joint, rather than merely the hip and knee. Development of this novel platform will be a substantial step toward the long-term goal of improving design and maneuverability in lower extremity assistive prostheses and robots.

Robotics is a high-impact way to attract the attention of future engineers. Outreach activities are included to that spark and sustain STEM interest in pre-college students, especially underrepresented minorities. Development of an inexpensive powered ankle-foot prosthesis will improve well-being of Wounded Warriors and civilian amputees, while at the same time inspiring and training the future STEM workforce. In addition, a newly developed a low-cost EMG-controlled manipulator will be included as an educational platform that will be used in outreach programs to teach fundamentals of mechatronics, robotics, and biomechanics to K-12, community college, undergraduate, and graduate students.