ARC Collaborative Research Seminar Series
Fall 2011

ARC members can download the presentation files on our password-access online portal iARC.
Non-ARC members please email arcweb-info@umich.edu with your requests.

If you wish to attend the seminar remotely, please contact William Lim (choonhun@umich.edu) for teleconference details.


September 16th, Friday (9:00-11:00am)
University of Michigan, Lurie Engineering Center, 3rd Floor, Johnson Rooms B & C

Battery Thermal Packing Optimization
Paolo Guarneri, Brian Dandurand, Ravi Teja Katragadda, Aravind Shanthakumar, Margaret Wiecek, Georges Fadel (Clemson University)

Scalable Stack Battery Thermal Model
Anna Stefanopoulou (PI), Jason Siegel, XinFan Lin, Hector Perez, (University of Michigan), Yi Ding, Matthew Castanier (TARDEC)

Click here for abstracts (pdf)


September 30th, Friday (9:00-11:00am)
University of Michigan, Lurie Engineering Center, 3rd Floor, Johnson Rooms B & C

Estimation of the Ignition Delay from the Measured Crankshaft Speed
Dinu Taraza (Wayne State University)

Synthetic Fuels and Study of Fuel Volatility and Cetane Rating
Naeim Henein (Wayne State University)

Autoignition Characteristics of Military Fuels: JP8, ULSD, Synthetic and Biodiesel Fuels
Naeim Henein (Wayne State University)

Combustion Behavior of a Modern Heavy-Duty Diesel Engine Using JP-8
Dohoy Jung, Jason Martz (University of Michigan)

Click here for abstracts (pdf)


October 28th, Friday (11:00am-1:00pm)
University of Michigan, Electrical Engineering and Computer Science (EECS) Building, Room 1008

Preamble by Dr. Jim Overholt
Senior Research Scientist for Robotics, U.S. Army TARDEC

Enhanced Reliability for Tele-operated Mobile Robots
Johann Borenstein (University of Michigan)

Integrated Power Systems for Improved Mobility of Ground Robots
Huei Peng (University of Michigan)

Click here for abstracts (pdf)


November 4th, Friday (9:00-11:00am)
University of Michigan, Electrical Engineering and Computer Science Building, Room 1008

I-RBDO Code for Reliability Analysis & Reliability-Based Design Optimization
K.K. Choi, Ikjin Lee, Liang Zhao, Yoojeong Noh, Byeng Youn, Jian Tu, Nick Gaul, and Hyeongjin Song, The University of Iowa
David Gorsich and David Lamb, US Army TARDEC

Adaptive Virtual Support Vector Machine for Reliability Analysis of High-Dimensional Problems
K.K. Choi, Ikjin Lee, Liang Zhao, Yoojeong Noh, Byeng Youn, Jian Tu, Nick Gaul, and Hyeongjin Song, The University of Iowa
David Gorsich and David Lamb, US Army TARDEC

Next-Generation Parametric Reduced-Order Models for Design Modifications and Robust Signal Processing
Sung Kwon Hong, Bogdan I. Epureanu, The University of Michigan
Matthew P. Castanier, U.S. Army TARDEC

Click here for abstracts (pdf)


November 18th, Friday (11:00am-1:00pm)
University of Michigan, Electrical Engineering and Computer Science Building, Room 1008

UGV System Reliability Modeling and Improvement
A. Galip Ulsoy (University of Michigan)

The research proposes a unified methodology for improving UGV mission reliability in three deployment phases of the UGV lifecycle to a) remove design deficiencies through simulation-guided acceptance testing before the field deployment; b) prevent mission failure by real time monitoring, prediction and online task planning during mission execution, as well as reduce human induced operational failures with an intelligent human-UGV user interface; and c) analyze failure data after the mission execution for causal modeling and reliability improvement. A second focus is to improve the reliability, utility and efficiency of a robot arm, by using optimized passive energy storage elements in parallel with robot joint motors. Preliminary experiments demonstrate torque reductions of about 50%, and 5 to 25% improvements in energy efficiency.

Reconfigurable Control for Failure Prevention and Recovery
Dawn Tilbury and Ella Atkins (University of Michigan)

Robot failures can lead to costly downtime, both for the armed forces who have to pay to have the robot repaired, as well as the soldiers who no longer have a buffer between them and the explosive objects in the field. Having discussed the Packbot operation with Army technicians at JRRF, it is evident from their anecdotal experience that manipulator arms, mobility systems, limited battery power, and thermal overload all contribute to the high rate of failures. Since the UGV platforms are typically overactuated, reconfigurable or fault-tolerant control has the potential to allow continued operation of UGVs even in the presence of failed actuators and/or sensors the operator would find difficult to manage via direct teleoperation. Our overall research goal is develops models, algorithms and methods both to prevent failures from occurring and to recover from or adapt to failures after they occur. In this presentation, we will first present the context of our research in terms of mission scenarios that describe the required goals and actions a robot must execute. We then briefly present three pieces of the overall control solution. First, we describe a reconfigurable control method for the Packbot manipulator arm with failed joints. Second, we present results on thermal modeling of the Packbot that could be used in a prediction methodology to predict overheating. Finally, we present an energy-aware coverage algorithm that takes into account the available battery power. We will conclude with some discussion of our ongoing and future work.


December 9th, Friday (9:00-11:00am)
University of Michigan, Electrical Engineering and Computer Science Building, Room 1008

Advancements in TerrainSim: Terrain Characterization, Modeling, Analysis, and Synthesis Software
Phil Chin, John B. Ferris (Virginia Tech)

Terrain is the main excitation to a vehicle and remains a consistent excitation as changes to the vehicle design are contemplated. The fundamental problem that is addressed is that terrain topology is a very rich and complex signal that has significant physical characteristics over a wide range of wavelengths. In order to study terrain characteristics, TerrainSim software has been successfully designed and implemented in a GUI to provide multiple modeling and synthesis techniques (Autoregression, Markov Chains, Wavelets), a comprehensive set of statistical analyses (linearity, Gaussianity, etc.) comparing measured and synthesized road profiles. In this presentation, the addition of new modeling techniques in TerrainSim will be demonstrated. The technical approach to enhance TerrainSim to model 3D surfaces and deformable off-road terrain is discussed. The current results indicate that TerrainSim is a powerful modeling and simulation tool, applicable to full surfaces, profiles, and their decompositions.

Off-Road Soft Soil Tire Model Development, Validation, and Interface to Commercial Multibody Dynamics Software
Corina Sandu (Virginia Tech)

The goal of this project is to develop a more realistic, comprehensive, and efficient off-road tire model for soft soil applications as needed to support current Army simulation needs. The proposed approach is a detailed semi-analytical tire model for soft soil that utilizes tire construction details which parallel commercially available on-road tire models. The novelty relies on increasing the level of details for the tire model, in improving the tire-soil interface model, and by accounting for effects specific to terrain vehicles. The concept for the 3D tire model is presented. Simulation results for dynamic settling on rigid terrain and on soft soil are included, as well as results for straight forward driving at various slips. Progress on the soil testing experimental work conducted will be discussed. Experimental results for the tire testing on soft soil in the lab will be presented, for various slips. Future work will be proposed.

Elasto-Hydrodynamic Frictional Losses Induced by the Ring-Pack of the Piston-Assembly
Nabil Chalhoub (Wayne State University)

The intricate dynamics of the piston-assembly have significant impact on engine fuel economy, oil consumption, thermal efficiency, wear, and noise. The present study focuses on developing a reliable tool to provide engine designers and manufacturers with valuable insights into the dynamic behavior and the lubrication regimes of the piston-assembly. The formulation predicts the rigid body motion of the crank-slider mechanism and the piston secondary motions. Moreover, each ring is modeled as an independent shear deformable structure undergoing both rigid and flexible motions within its piston groove. Both ring-liner and ring-groove interactions are accounted for in the formulation, which considers the impact problem arising from the collision of the rings with their respective grooves. The solid-fluid interaction has also been considered to determine the frictional losses associated with the elasto-hydrodynamic lubrication regime of the ring-pack. The capability of the tool will be demonstrated through digital simulations.


December 16th, Friday (9:00-11:00am)
University of Michigan, , Electrical Engineering and Computer Science Building, Room 1005

Computationally-Efficient Finite-Element-Based Thermal Models of Electric Machines
Kan Zhou, Heath Hofmann (University of Michigan)

Knowledge of the internal temperatures of an electric machine under real-time operating conditions would be extremely useful in order to determine its torque capabilities. This knowledge is also useful for full-scale electric vehicle simulation and optimization. In this paper we present a technique for developing computationally-efficient thermal models for electric machines that can be used for real-time thermal observers and vehicle-level simulation and optimization. The technique is based upon simulating the eigenmode of the system as determined by finite element analysis. The order of the model is then dramatically reduced in two ways. First, the extent of excitation of each mode is calculated, and only eigenmodes that are significantly excited are included in the dynamic model; other eigenmodes are treated as static modes. Second, only a few “hot spots” in various regions are chosen. The result is a thermal model that can accurately model internal temperatures of the machine while requiring the modeling of only a handful of states. Such a model can be used in vehicle simulations, or for real-time observers in actual vehicles. The computation time of the model presented in this paper is dramatically reduced compared with a typical full–order finite element model.

Ultracapacitor Energy Storage for Improving Fuel Economy and Extending Battery Life in Heavy Vehicles
Yasha Parvini, Ardalan Vahidi (Clemson University)

The power demands imposed on a heavy vehicle can be substantially higher than those seen in smaller vehicles due to its larger mass. The high power capability of ultracapacitors is well suited to assisting a heavy hybrid vehicle in meeting these high power demands. Because of the properties which differentiate ultracapacitors from batteries, high power-density ultracapacitors may be integrated with a vehicle powertrain to boost available power during vehicle acceleration and relax engine transients, making them an effective mechanism for reducing fuel consumption without compromising vehicle agility.
In this presentation potential fuel economy gains enabled by ultracapacitor assist is shown first, based on high fidelity simulations of a cargo truck. A few of existing ultracapacitor hybrid implementations are reviewed, including our test-bench implementation. This leads to a discussion of challenges and technology bottlenecks. In particular we emphasize the power electronic needs when ultracapacitors are used as the main energy storage and calculate attainable energy recovery efficiencies in regeneration events.

Design and Fabrication of High Energy, Asymmetric Supercapacitors
Priyanka Pande, Paul Rasmussen and Levi T. Thompson (University of Michigan)

Batteries are the principal energy storage devices used for military and commercial applications. While these devices can have energy densities exceeding 100 Wh/kg, this energy is difficult to fully access in pulsed and high power applications due to the relatively slow kinetics associated with their redox processes. Supercapacitors are based on very fast and highly reversible processes and offer high power at modest energy densities. To achieve broader application, these devices will have to deliver higher energy densities. This talk will describe our efforts to develop nanostructured early transition metal nitrides and carbides for use in high energy density, asymmetric supercapacitors. In addition to performance characteristics, we will discuss the charge storage mechanisms for these materials and design features for these devices.


ARC members can download the presentation files on our password-access online portal iARC.
Non-ARC members please email arcweb-info@umich.edu with your requests.