The Solid Modeling Laboratory is used for research in integrated automation of geometry-based engineering applications. The Robotics Laboratory features several research-quality robot arms, vision systems, and workstations with state-of-the-art robotics software. A Mechatronics Laboratory for the integration of electrical and mechanical systems is under development. The Nondestructive Testing and Evaluation Research Laboratory provides acoustic emission, ultrasonics, acousto-ultrasonics, eddy-current, magnetic particle, holography, and real-time microfocus x-ray equipment for nondestructive evaluation/characterization of a variety of materials and structures. The Decision Systems Laboratory focuses on the development of decision support systems utilizing both operations research and artificial intelligence techniques. In the Manufacturing Systems Laboratory, new modeling, decision making, and control techniques to improve the efficiency of large-scale manufacturing systems are investigated. The Illinois Genetic Algorithms Laboratory investigates the theory and application of genetic algorithms search procedures based on the mechanics of natural selection and natural genetics. In the Algorithm Visualization Laboratory, the performance of numerical methods in engineering applications is studied using computer graphics.
Many long-term wheelchair users suffer from chronic shoulder pain.
This problem is significantly caused by the loads acting upon the
upper extremity and trunk during the wheelchair propulsion. This
project involves the mathematical development and determination of the
upper extremity joint forces and moments during wheelchair propulsion.
The upper extremity and the trunk are modeled by a 3-D four-bar link
system representing trunk, arm, forearm, and hand and with 10 degrees
of freedom. Included in the model also are the significant muscle
forces. Knowing the hand-rim interface loads and geometric factors of
the wheelchair, the optimal wheelchair/user match may be obtained.
Bones in normal condition are electropositive. When one is broken,
there are electronegative charges around the broken part which
enhances the healing process. Although there are some invasive
approaches to maintain this electronegativity, noninvasive
electromagnetic stimulators are preferred. This project involves the
development of a biomechanical model of the bone-healing process. The
model will be used to obtain the optimal design parameters, such as
wave form, intensity, and geometric parameters, for the most efficient
bone-healing process. Two new strategies, discontinuous stimulation
and time-dependent stimulation, will be considered. A laboratory
prototype stimulator using optimal parameters will be designed and
manufactured.
Walking is the basic means of locomotion for human beings. Various
aspects of walking have been studied by a number of researchers;
however, there is limited information on the unique characteristics of
changing direction during walking. This study investigates the kinetic
walking patterns and properties of the ground reaction forces (GRF) in
changing direction. Thirty-three subjects are tested through a walking
protocol representative of all of the complex movements of directional
walking. Their GRF and body movements are recorded via a force plate
and motion analysis systems, respectively. The insight gained in this
study will be helpful in the clinical diagnosis of dysfunctional
walking.
The purpose of this research is to investigate the sequential motion
and interaction of the upper extremity in underarm throw through the
study of the relationship between kinematic factors and muscle
activities. The proximal-to-distal sequential motion (a whip lash-like
action) of the upper extremity is frequently associated not only with
fast movements, such as throwing and kicking, but also with slow
movements, such as running and walking. Kinematic data of several
subjects are collected via high-speed cameras and digitizing systems
and selected muscle activites are recorded by surface-mounted
electrodes. The results of this study will enhance understanding of
the muscle usage, joint forces, and torque and provide the
biomechanical basis for the prevention and prediction of injuries in
various sport activities.
Power tools are used daily by the professional and the handyman. They
can be great time savers or products that can deliver lacerations,
amputations, or death. Research has focused on the guards on saws and
how the saws are used. Tests have shown that some saws have guards
that will move out of the way if they are accidentally bumped by the
user. A 5500 rpm blade is the next object to come in contact with the
hand after the guard has moved. Considering human movements when
designing power tools will increase their safety.
The analysis and design of some types of structures must be performed
with due consideration to material and geometric nonlinearities.
Typical structural elements are governed by underlying power function
relationships between the dimensions of the member and its
forces/stresses. Yet, when nonlinearization is typically used, it
inadequately models power function behavior. This project concerns an
alternative type of linearization that has significant advantages when
applied to nonlinear structural systems. It provides a higher quality
approximation to the nonlinear behavior, allowing significantly larger
steps to be taken in incremental methods.
Traditionally, performance analysis and routing algorithms for
connection-oriented telecommunication networks were studied for only
one type of connection, i.e., voice calls. However, there are two main
features that distinguish emerging networks from voice networks:
general network topology and multiple traffic classes having widely
different arrival and departure characteristics. The main thrust of
this research is to address the myriad challenges that arise due to
these characteristics of integrated services networks. Specifically,
we focus on developing optimal admission control and routing schemes
and fast, accurate analytic and simulation techniques to evaluate the
performance of these schemes.
A new hierarchical framework for the intelligent control of large-
scale, discrete-event systems has been formulated. The conceptualized
hierarchy defines a coordinated object that can be employed
recursively to describe the desired hierarchy. To provide for
distributed intelligent control, a hierarchical subsystem coordinator
is included within each coordinated object. The essential mechanisms
to coordinate the distributed decision making and control are now
being explored. New object-oriented simulation tools are also being
developed to model the interaction among the coordinated objects.
Using a new object-oriented simulation framework, a distributed
software emulator is being developed for the rapid access to
manufactured parts (RAMP) flexible manufacturing systems (FMS)
operated by the Department of Defense. The emulator models by defining
distributed central objects for each of the 70 controllers. The
controllers interpret with a client server. The same server also
manages the Java-based controller allowing the emulation to be viewed
anywhere on the World Wide Web. The project will eventually seek to
produce a real-time scheduler for the RAMP FMSs.
The notion of "steering quality" is difficult to quantify in
the design of steering systems for earth-moving vehicles. We envision
an expert driver operating a simulated vehicle within a virtual
environment where the parameters in the design of a steering system
can be altered instantaneously. In this paradigm, the process of
trial-and-error design becomes a viable option. This project involves
the derivation of vehicle models of appropriate complexity and detail
that can be simulated in real-time within a virtual environment. To
improve the real-time performance of these models, particular
attention is focused on artificial neural networks.
This research considers design of a nonlinear, variable structure
controller for multivariable nonlinear systems. The controller is
based on the concept of polar partition of the polar control and is
intended to insure semiglobal stability, to be robust to plant
perturbations, and to possess qualities of interest in such
applications as fast prototyping and off-the-shelf availability.
This research considers control scheduling and
communication/control/sensing issues in the regulation of lateral and
longitudinal motion of vehicles participating in high flow density,
multilane traffic. The goal is to survey present approaches to the
problem and develop control strategies and control schedules to enable
lane maneuvers and entrance into/exit from traffic, when traffic in
each lane is moving at different target velocities.
The need to continuously operate technical systems in the presence of
structural changes in the system, damage to parts of the system, or
failures in the control system has long been recognized as an
important issue in system design and operational control. The project
emphasis is on the development of systematic procedures for the design
of fault-tolerant control systems. The focus is on design of reliable
control systems using redundant sensors and actuators, on fault
assessment methods, reconfiguration procedures and development of
controllers based on coarse partitioning of the state space, using
methods based on variable structure control, cell-to-cell mapping, and
state space partitioning.
The objective in this project is the development and evaluation of
reconfigurable control algorithms for the new generation of tailless
fighter aircraft. The main effort is placed on the provision of system
identification algorithms that are reliable, fast for on-line
implementation, and efficiently support reconfigurable dynamic
inversion control laws. The overall reconfigurable system is tested
and evaluated on nonreal-time simulation as well as real-time piloted
simulation using the McDonnell Douglas facilities.
Hydrogenerator governors are designed with predetermined rotational
inertias and conduit dimensions for maximum acceptable off-speeds
(speed deviations from reference). However, this parameter selection
may not be favourable for stable operation and satisfactory small
signal level performance when governing isolated loads. Poorly
governed plants operating in interconnected systems degrade the
overall stability. This work develops a graphical method to determine
expected performance and stability characteristics based on inertia
and conduit sizing decisions. It is directed toward mechanical and
civil engineers involved in the design and associated economics of
plant layouts.
A number of published works deal with governor tuning for speed
control of hydrogenerators. This work is based on the hypothesis that
some system parameters are not known at the design stage. It develops
a graph that can be used to predict optimum proportional and integral
gains based on four parameters: the time constants of the water column
and the rotor inertia and the self-regulation constants of the turbine
and the loading grid. The pole cancellation method of design is used
and the results are posed in an easy-to-use format not requiring the
solution of systems of equations.
This research investigates an optimal strategy for controlling the
speed response of Kaplan hydrogenerating systems to decreases in load.
Typically, primary control gates restrict and redirect water through
the turbine to stabilize and transfer the system to operating point
demand. The adjustable turbine blade angle is used to return to
maximum operating efficiency at the new load level. The overspeed
reduction is limited by the conduit's ability to withstand the
overpressure caused by the flow restriction at the turbine. A control
scheme using gates and blades simultaneously and independently is
developed.
We concern ourselves with 11 broad research issues in the modeling,
analysis, control, and performance evaluation of Discrete Event
Dynamic Systems (DEDS). Research in modeling and analysis concerns the
identification of modeling paradigms suitable for supervisory control
of DEDS. The control of DEDS concerns the archetypal problem of
elimination of deadlocks. The performance analysis of DEDS concerns an
approach that will permit a system designer to modify automatically
discrete event simulation programs that only estimate performance so
as to efficiently obtain the sensitivity of the performance. This
sensitivity information can be used toward system optimization using
stochastic approximation techniques.
The main objectives of this research are twofold: (1) a synthesis of
descriptive, normative, and prescriptive aspects of decision making
and (2) a synthesis of decision theoretical approaches for decision
aiding and artificial intelligence techniques for problem solving. The
result of this research is expected to be a computational theory of
decision making for developing automated decision tools. The
application domain under consideration is the scheduling problem in
manufacturing.
The traditional approach to manufacturing control systems is the so-
called push strategy, such as material requirement planning (MRP). The
Japanese alternative is the "pull" strategy in which the
material supply is just-in-time (JIT). It is becoming evident that
neither one is consistently better than the other. In fact, in many
instances, a hybrid approach is more superior, depending upon the
manufacturing system. However, it is not known which characteristics
of the manufacturing system affect the performance of different
strategies. The main objectives of this research are to identify the
factors affecting the performance of the manufacturing control
strategy and to design an optimal hybrid strategy parameterized by the
characteristics of the manufacturing system.
Empirical data indicate that microlevel engineering and management by
themselves are not adequate for improving the rate of increase of
productivity in manufacturing. This research identifies technology
management and production techniques to be the major contributors to
an increase in productivity. Under investigation is development of
models for organizing macro- (e.g., government, university) and micro-
(e.g., firm, union) agents around technology development and adoption,
as well as innovative production processes.
A first-of-its-kind emulator for an FMS has been constructed to test
algorithms for the distributed real-time scheduling and control of
large-scale, discrete-event systems. A network of 13 computers defines
the control hierarchy. An automated guided vehicle and an automated
storage and retrieval system are included for material handling. Four
generic processing and one fixturing station will have virtual
processing capability. Eventually we will construct a second FMS
emulator and a coordinator to synchronize production in both FMSs over
the World Wide Web. The emulator will also be employed as an
educational laboratory in several manufacturing engineering courses.
A new object-oriented simulation approach is being developed for the
production planning problem. The approach will permit the product
structure diagram and specialized policies for managing the inventory
for each product to be considered. Finally, the simulation approach
defines a generalized queue for all staged and dispatched orders so
that a generic interface to any investigated decision algorithm for
managing the production can be provided. Eventually, the modeling will
be expanded to consider the purchasing of materials from external
vendors, material and capacity requirements planning, and real-time
production scheduling.
This research deals with integrating three stages of the quality
control and assurance process in a manufacturing or assembly
environment: design, manufacturing, and fault-detection stages. The
principal objectives of this research are twofold. First, a
probabilistic network model (PNM) is to be developed as a diagnostic
tool. For this purpose, the existing PNMs, such as influence diagrams,
belief networks, and path analysis, are investigated. The second
objective is the integration of the PNM with the data from SPC charts
and with the robust design techniques. The results are to be applied
to the Italtel's printed circuit board production process in Milan,
Italy.
A computational method employing the conventional means of finite-
element analysis is being developed for the statical analysis of
underconstrained structural systems. The method features the
comprehensive stiffness matrix combining the two principal sources of
first-order structural stiffness--elastic and statical-kinematic.
Evaluating the statical-kinematic stiffness requires knowing the
member forces produced by the equilibrium part of the applied load.
These forces are found by modifying the singular elastic stiffness
matrix. With the construction of the comprehensive stiffness matrix
accomplished by the conventional finite-element means, the method can
be incorporated into structural analysis software.
Designers are aware that product quality, manufacturing cost,
environmental impact, and product development time are all important.
However, they tend to address each of these issues in isolation. Then,
the crucial and inevitable tradeoff decisions are often made in an
unstructured, ad hoc manner. Designers lack a single metric which
encompasses all these important issues simultaneously. In their
analytic arsenal, designers need procedures for quantifying the
appropriate tradeoffs among conflicting objectives. Our goal is to
develop a multiobjective manufacturing metric and incorporate it into
technical design analysis in a systematic, rigorous manner.
This project develops a rigorous new method for integrating
quantitative decision analysis over the entire range of product
design, manufacture, use, and disposal. Specifically, the methodology
combines statistical manufacturing process control with life-cycle
analysis and concurrent multiobjective design optimization. Pollution
and its removal cost are treated as product defects. This project
significantly expands on previous work to develop design tools that
can be used by any industry. Procedures for classes of manufacturing
processes and their resultant waste streams are specified. The best
combination of strategies is identified, including specification of
the product design, materials, manufacturing process design, and
manufacturing process control settings.
The thrust of this project is to develop improved instructional
materials and methods for engineering design graphics. Computer
software employing three-dimensional databases is being used to
achieve this goal.
This work combines the best features of the fast messy genetic
algorithm (fmGA), the gene expression messy genetic algorithm (gemGA),
and the linkage learning genetic algorithm (LLGA) to create a broadly
competent GA that solves an array of hard problems quickly,
accurately, and reliably. Once developed, the so-called evolving
expression-linkage GA (eelGA) will be applied to a problem of U.S. Air
Force interest, and a series of seminars will be held to disseminate
the methods and procedures to a variety of air force personnel and
contractors.
This project funds travel and ancillary expenses to permit the
principal investigator to visit the Indian Institute of Technology,
Madras, and collaborate with C. S. Krishnamoorthy of the Department of
Civil Engineering. The goal of the project is combine Illinois
foundational and theoretical knowledge of genetic algorithms with IIT
structural and GA applications experience to create a structural
optimization system capable of solving difficult, large-scale
structural problems.
This project builds on the fast, accurate, reliable results obtained
using fast messy genetic algorithms and investigates four means of
obtaining even faster results: (1) spatial efficiencies, (2) temporal
efficiencies, (3) sampling efficiencies and evaluation relaxations,
and (4) systematic convergence criterion relaxations. Primary among
these are spatial and temporal efficiencies, and the efficient use of
space and time are critical to obtaining fast results on both serial
and parallel machines. Bounding analytical studies show how to do the
appropriate decomposition and empirical studies to verify the speedup.
Although the work is intended for the speedup of messy GAs in
particular, the study generalizes to almost all evolutionary
computations with little or no modification.
This project builds on a recently developed model of population sizing
for simple GAs to obtain models for bounding cases of parallel GAs.
Our objective is to provide practitioners with simple ways to
determine how to use their computational resources to find a solution
of a desired quality. The bounding models cover the spectrum isolated
subpopulations to completely connected subpopulations with maximal
migration rates. They can be used to predict the parallel speedups
attained with different communication schemes. The models also show
that under some circumstances there is an optimal spatial allocation
of individuals and that the expected execution time can be minimized.
Models are being developed to account for the conditional reliability
of structures. For example, successful past performance of a
nondeteriorating structure has a proof load effect that increases its
reliability estimate for subsequent service and decreases the
likelihood of gross error in strength. For deteriorating systems,
uncertainty of the state of the system grows significantly with time.
Thus, reliability models are being developed that can combine new
information, such as test or inspection results, with older estimates
of serviceability, and enable the costs and expected value of new test
information to be balanced against each other, and against nontest
options.
For economical reasons, many structural members are produced in fixed
sizes rather than in a continuous supply of structural shapes. This
presents an interesting optimization problem, namely, how to design an
assortment of profiles or sizes to best satisfy a structural demand.
One solution approach is to minimize the material waste from
overdesign that occurs when standardized sizes are selected rather
than "made-to-order" cross sections. Related problems
include the modeling of economy of scale and the optimal consolidation
of production materials.
The ability of a structural control system to maintain stability is
measured by its robustness. When parameter uncertainty is modeled by a
probability distribution, robustness becomes analogous to system
reliability, in which the joint distribution is of dimension equal to
the number of uncertain parameters and the failure boundary is defined
by the onset of instability. In the approach taken, root loci provide
a mapping of system performance into the parameter space, defining
failure boundaries. System reliability methods are then used to assess
system robustness from the set of all modal failure regions. A further
benefit is the ability to revise the robustness measure when new
information from testing or observation is obtained.
Reliability models of structural design are extended to cover the use
of load testing for design of new structures or evaluation of existing
structures. Approaches are being developed to incorporate into
decision making the information from sample tests, single-mode or
multimode proof tests, and other sources. These and other load-testing
models allow both test and nontest information on strength and safety
to be used in the evaluation of a structure. Procedures for design by
testing can be assessed for their likely effects on achieved
reliability, and design resistance factors can be found that account
for test uncertainties.
This research investigates stability changes associated with theater
missiles and theater missile defenses.
The scope of this work is to provide an objective view of the relative
advantages and limitations of the nondestructive testing and
evaluation (NDTE) methods that are currently being used in the
evaluation of bridge decks with bituminous overlays. Several NDTE
techniques will be evaluated and a nondestructive testing and
evaluation procedure, including methodology and equipment to evalu-ate
concrete bridge decks with asphalt overlays, will be presented.
Presently, the most commonly used tests to assess the structural
integrity of particleboard are the boil swell and the cyclic soak
tests. Although these tests predict how well the particleboard will
perform, with the exception of visual examination, there are at
present no nondestructive evaluation (NDE) techniques for its
structural integrity. The purpose of this study is to investigate the
applicability of the acousto-ultrasonic technique to assess the
functional structural integrity of particleboard. During the pressing
operation, wood-based composite materials are compressed in thickness
beyond the gross density of the wood species and remain compressed
because of resin bonding.
Failure of rope can result in significant property damage and/or
personal injury. Because ropes can fail with no quantifiable change in
visual appearance, the development of nondestructive testing
evaluation techniques is essential in improving the safety and
reliability of operations involving rope. The purpose of this study is
to investigate the applicability of the acousto-ultrasonic stress wave
factor technique to the nondestructive evaluation of nylon and kevlar
ropes.
A nondestructive technique to evaluate the strength of wood in early
stages of decay is being investigated. Although the "pick
test" is commonly used to detect wood decay in the field, it has
not been known how advanced decay must be before it can be detected by
this means. Because much of the wood's strength is lost in the early
stages of decay, a high-sensitivity testing procedure is desirable.
The importance of this research can be appreciated by noting that for
each real estate transaction only a termite inspection is required
even though the wood frame structure may have reached moderate or
advanced stages of decay.
Concrete is unusual among construction materials in that it is
manufactured as used and cannot be tested for acceptance in advance.
Acceptance is commonly based on strength tests at an advanced age.
Clearly, a need exists to assess the quality of concrete much earlier,
ideally before it is placed. It is generally agreed that the most
important parameter for determining the quality of concrete is the
water-cement ratio. The objective of this study is to investigate a
procedure for the instantaneous determination of water-cement ratio to
allow a go/no go decision on an actual batch prior to discharge.
Laminated safety glass is widely used in architectural applications
and in windshields of motor vehicles. The purpose of this study is to
nondestructively evaluate the adhesive bond strength between the
plastic interlayer and the two adjacent glass plates in laminated
safety glass.
Friction welds are currently used in plastic components of air intake
manifolds. The evaluation/characterization of the weld (weld defects
as well as the strength) is important for the structural integrity of
this component. The purpose of this project is to develop a robust
nondestructive testing and evaluation method to evaluate/characterize
friction welds in plastic components. Both the ultrasonic immersion C-
scan method and the acousto-ultrasonic approach will be used to
evaluate/characterize friction welds.
Underinflated or run-flat radial truck tires can be subjected to steel
cord fatigue damage caused by overflexing of the tire. Weakened cords
may break with potential catastrophic consequences such as loss of
life. The purpose of this project is to develop a prototype instrument
capable of 100% on-line inspection of new or retreaded tires. The
instrument should provide easily interpreted results (color-coded
scans) to reduce the possibility of operator error.
Using impulse-echo (IE), spectral analysis of surface wave (SASW),
pulse velocity (PV), and acousto-ultrasonics (AU), the purpose of this
project is to develop an instrument capable of scanning airport
pavements to evaluate layer thicknesses, material properties, and
defects such as damage accumulation and delaminations. The output of
this instrument should include a color-coded feature pavement scan.
Segregation is the separation of the coarse and fine aggregate
particles from a mass containing a variety of particle sizes. Current
methods of detecting and evaluating segregation are basically
qualitative and strongly operator dependent. The purpose of this
project is to develop a nondestructive testing and evaluation method
to quantitatively evaluate/characterize porosity and segregation in
asphalt concrete.
The objective of this work is to develop a methodology for on-line
monitoring of incipient die/punch failure in cold-heading processes in
order to assure parts within specified tolerances. Current work
consists in developing transducers and AI signal processing software
(that is, neural nets) to make the monitoring process more adaptive,
less operator dependent, and therefore more reliable.
Construction planners face the decisions of selecting appropriate
resources, including crew sizes, equipment, methods, and technologies,
to perform the tasks of a construction project. In general there is a
tradeoff between time and cost--the less expensive the resources, the
longer it takes. Using CPM techniques, the overall project cost can be
reduced by using less expensive resources for noncritical activities
without impacting the duration. This project concerns a lower-bounding
technique to generate a high-quality estimate of the overall time-cost
trade-off curve of a project.
This project concerns the integration of machine learning and sensor-
based control in intelligent robotic systems. The research combines
techniques of explanation-based control with robust and adaptive
nonlinear control, computer vision, and robot motion planning. We wish
to go beyond the strict hierarchical control architectures typically
used in robotic systems by integrating modeling, dynamics, and control
at all levels of intelligence. Our ultimate goal is to combine
analytical techniques of nonlinear dynamics and control with
artificial intelligence into a single new paradigm, in which symbolic
reasoning holds an equal place with differential equation-based
modeling and control.
This project is to develop a three-degree-of-freedom air hockey-
playing robot. Research issues being addressed include real-time
visual serving, adaptive camera calibration and windowing, hybrid
estimation, and hybrid nonlinear control. Based on the reliability of
sensory information, a supervisory control system switches among a
fixed set of nonlinear controllers, each designed for a particular
task such as blocking or striking the puck. Future research is aimed
at learning through repetitive play.
This project seeks to develop stability and tracking results for
underactuated mechanical systems using tools from Lagrangian and
Hamiltonian dynamics, geometric nonlinear control theory, hybrid
control, and saturation. Our work exploits the underlying structure of
the nonlinear existing energy and passivity methods and more recent
backstepping methods, all of which attempt to exploit more fully the
inherent nonlinearities of the system, by "shaping" rather
than by "canceling" all of the nonlinearities in the system.
This project investigates the modeling of the sensorimotor control
systems in humans and robots. We use techniques from control theory
and artificial intelligence to understand dynamics and control of
human motion and the mechanisms by which humans learn sensorimotor
control. At the same time, we use studies of human motion to aid the
development of improved control techniques for mechanical systems.
Future applications of our work will include more dextrous robots and
more effective diagnostics and physical therapy approaches for
disabled humans, as well as better balance training and fall-
prevention programs for elderly and individuals with balance deficits.
This project concerns the nonlinear control of underactuated
mechanical systems. This class of systems is quite broad and
encompasses flexible structures of all kinds including flexible link
robots, flexible joint robots, as well as robot models that include
actuator dynamics, and many of the classical control problems like the
ball-and-beam and cart-pole systems. Techniques such as partial
feedback linearization, singular perturbations, and passivity methods
are being applied for global and semiglobal stabilization of these
systems.
Thermal and misalignment effects on the operation of railroad bearing
are examined. In the thermal analysis, a finite-element model is being
developed to examine the seizure process in railroad bearings as a
function of speed, load, and lateral play. Maps will be developed
indicating seizure thresholds as a function of these variables. How
adapter wear affects bearing life is also being examined through
modeling of the adapter/bearing/axle assembly. Obtaining both linear
and angular stiffnesses of these components is a major part of the
modeling process.
Automobile behavior and control are studied in the presence of
significant crosswinds. Qualitative and quantitative measures of
performance have been modeled and results compiled for a variety of
vehicles (automobiles, sport/utility vehicles, vans, and pick-up
trucks).
Vehicles with locked wheels exhibit both yaw and lateral instability
in addition to roughly longitudinal deceleration. This work focuses on
calculation of vehicle trajectories under such conditions.
Road vehicle aerodynamics has up to now been concentrated on drag
reduction. This work examines potential handling and braking
performance improvements that could be made through proper use of
vehicle aerodynamics. The practicality of the enhancements is also
addressed in light of packaging and styling considerations.
This work examines the vehicle dynamics associated with a single flat
tire at various locations on automobiles. Fixed control and active
steering vehicle dynamic response are studied. Effects associated with
understeer/oversteer, tire capabilities, and vehicle inertial
properties are included. Effects of underinflation of a pair of tires
are also included. A road vehicle and a racing car are examined.
Vehicle dynamics associated with a vehicle with a locked rear end (no
differential, rear-wheel-drive) are of interest, especially in racing
and off-road performance. A limited-slip differential constitutes a
special case of such behavior. In this work, handling characteristics
and nonlimit-performance maneuvering are modeled. New results for
changes in understeer/oversteer are developed, and improvement or
degradation of vehicle performance is addressed.
Communications Networks
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PERKINS, J. and R. SRIKANT. Scheduling multiple part types in a prone single machine flexible manufacturing system. IEEE Trans. Automat. Contr., 42, 364-377 (1997).
Control Systems
DIONG, B. M and J. V. MEDANIC. Simplex-type variable structure controller design for systems with nonmatching disturbances and uncertainties. Int. J. Contr., 68:3, 625-656 (1997).
RAMASWAMY, D., J. V. MEDANIC, W. R. PERKINS, and R. BENEKOHAL. Lane assignment on automated highway systems. IEEE Trans. Vehic. Technol., 46:3, 755-769 (1997).
SREENIVAS, R. S. On Commoner's liveness theorem and supervisory policies that enforce liveness in free-choice petri nets. Syst. Contr. Lett., 31, 41-48 (1997).
SREENIVAS, R. S. On supervisory policies that enforce global fairness and bounded fairness in partially controlled petri nets. Discrete Event Dyn. Syst.: Theory and Appl., 7:2, 191-208 (1997).
SREENIVAS, R. S. On the existence of supervisory policies that enforce liveness in discrete event dynamic systems modeled by controlled petri nets. IEEE Trans. Automat. Contr., 42:7, 928-945 (1997).
SREENIVAS, R. S. On Commoner's liveness theorem and supervisory policies that enforce liveness in free-choice petri nets. Syst. Contr. Lett., 31, 41-48 (1997).
Evolutionary Computation
CANTU-PAZ, E. and D. E. GOLDBERG. Modeling idealized bounding cases of parallel genetic algorithms. Genetic Programming, 97, 353-361 (1997).
KARGUPTA, H., D. E. GOLDBERG, and L. WANG. Extending the class of order-k delineable problems for the gene expression messy genetic algorithm. Genetic Programming, 97, 364-369 (1997).
Integrated Mechanical and Structural Design
KUZNETSOV, E. N. Geometric analysis of woven or braided reinforcement for use in composite shells. Composites Part B, 28B:5-6, 565-572 (1997).
KUZNETSOV, E. N. Orthogonal load resolution and statical-kinematic stiffness matrix. Int. J. Solids Struct., 34:28, 3657-3671 (1997).
Interdisciplinary Research
MAZUMDER, M. K., D. L. WANKUM, R. A. SIMS, J. R. MOUNTAIN, C. HUA, P. PETTIT, and T. CHASSER. Influence of powder properties on the performance of electrostatic coating process. J. Electrostat., 40-41, 369-374 (1997).
MUELLER, K. and S. A. BURNS. An alternative linearization technique. Engr. Computat., 14:7, 735-745 (1997).
PALMORE, J. Shadowing by computable orbits of continued fraction convergents for algebraic numbers, II. Complex Variables, 32:4, 263-272 (1997).
Operations Research
CAPELLO, W., R. COLYER, C. KERNEK, and J. V. CARNAHAN. Failure of the micron screw-in ring. J. Bone Joint Surgery, 75:5, 485-486 (1993).
FENG, C-W., L. LIU, and S. A. BURNS. Using genetic algorithms to solve construction time-cost trade-off problems. ASCE J. Comput. Civil Engr., 11:3, 184-189 (1997).
Robotics
DE SCHUTTER, J., H. BRUYNINCHX, W-H. ZHU, and M.W. SPONG. Force control: a bird's eye view. Control Problems in Robotics and Automation (Siciliano and Valavanis, eds.; Springer-Verlag) Lecture Notes in Control and Information Science, 230, 1-17 (1997).
SPONG, M.W. Underactuated mechanical systems. Control Problems in Robotics and Automation (Siciliano and Valavanis, eds.; Springer-Verlag) Lecture Notes in Control and Information Science, 230, 135-150 (1997).
ALVAREZ-GALLEGOS, J., D. CORTES, and M. W. SPONG. A stable control scheme for teleoperators with time delay. Int. J. Robotic Syst., 12:3, 73-79 (1997).
Tribology
YANG, F., T. F. CONRY, and J. C. M. LI. Squeezing flow of an Eyring fluid. ASME J. Tribol., 119, 593-596 (1997).
Vehicle Dynamics
RUHL, R. L. and M. HUDSON. Ventilated brake rotor air flow investigation. Overview of ABS/TCS Brakes, SAE SP-1229 (SAE 971033) 53-62 (1997).
RUHL, R. L. and R. A. RUHL. Prediction of steady state roll threshold for loaded flat bed trailers--theory and calculation. Heavy Duty Braking and Steering, SAE SP-1307 (SAE 976261) 39-49 (1997).
Biomechanics/Rehabilitation Engineering
MOEINZADEH, M. H. Biomechanics of shoulder injuries and the analysis of the dynamic motion of the upper limbs during wheelchair propulsion. Proc. 2nd Ann. Conf. of the Iranian Academic Assn. (IAA) (City College of New York, New York, N. Y., Sept. 1997).
Communications Networks
AETMAN, E., T. BASAR, and R. SRIKANT. Multi-user rate-based flow control: a team theoretic approach. IEEE Conf. on Decision and Contr. (Dec. 1997).
GREENBERG, A., R. SRIKANT, and W. WHITT. Resource-sharing between instantaneous-request and book-ahead calls. Int. Teletraffic Congr. (Jun. 1997).
LU, S., V. BHARGHAVAN, and R. SRIKANT. Fair scheduling in wireless packet networks. ACM Sigcomm (Sept. 1997).
V. SUBRAMANIAN and R. SRIKANT. Statistical multiplexing with priorities: tail probabilities of waiting times and queue lengths. IEEE Conf. on Decision and Contr. (Dec. 1997).
Control Systems
NORRIS, W. R. and R. S. SREENIVAS. On a control policy that maintains indoor air quality in a variable-air-volume air-handling unit. 1997 IEEE/ASME Conf. on Contr. Appl. (Hartford, Conn., Oct. 1997).
MEDANIC, J., M YUAN, and B. MEDANIC. Robust multivariable control of a two link excavator, Part A. Proc. 36th IEEE Conf. on Decision and Contr. (San Diego, Calif., Dec. 1997) 4231-4236 (1997).
SREENIVAS, R. S. On a free choice equivalent of a petri net. 36th IEEE Conf. on Decision and Contr. (San Diego, Calif., Dec. 1997).
Design and Manufacturing Systems
BISHOP, B. and M. W. SPONG. Adaptive calibration and control of 2D monocular visual servo systems. SYROCO '97 (Nantes, France, Sept. 1997) 525-530 (1997).
DAVIS, W. J., A. BROOK, and M. S. LEE. A simulation-based controller for a flexible manufacturing cell. Proc. 1997 IEEE Conf. on Syst., Man Cybernet., 3642-3647 (1997).
GONZALEZ, F. G. and W. J. DAVIS. A new simulation methodology for master production scheduling. Proc. 1997 IEEE Conf. on Syst., Man Cybernet., 1808-1813 (1997).
GONZALEZ, F. G. and W. J. DAVIS. A simulation-based controller for distributed discrete-event systems with application to flexible manufacturing. Proc. 1997 Winter Simulat. Conf. (Andradotir, Healy, Withers, and Nelson, eds.) 845-852S (1997).
WEILE, D. S., E. MICHIELSSEN, and D. E. GOLDBERG. Genetic algorithm design of Pareto optimal broad-band microwave absorbers. Proc. IEEE Symp. on Antennas and Propagat., 518-525 (1997).
Design Theory and Methodology
THURSTON, D. L. and J. L. ALVARADO. Structuring design optimization for multiple stakeholders over product life. Proc. Int. Conf. on Engr. Des. (Tampere, Finland, 1997).
THURSTON, D. L. and J. V. CARNAHAN. Statistical process control for pollution prevention. NSF Des. and Mfg. Syst. Grantees Conf. Proc. (Seattle, Wash., 1997).
THURSTON, D. L. and J. V. CARNAHAN. Statistical process control and optimization for pollution prevention. Proc. Int. Conf. on Engr. Des. (Tampere, Finland, 1997).
Evolutionary Computation
HARIK G. E. CANTU-PAZ, D. E. GOLDBERG, and B. L. MILLER. The gambler's ruin problem, genetic algorithms, and the sizing of populations. Proc. 1997 IEEE Int. Conf. on Evolutionary Computat., 7-12 (1997).
LOBO, F. and D. E. GOLDBERG. Decision making in a hybrid genetic algorithm. Proc. 1997 IEEE Int. Conf. on Evolutionary Computat., 121-125 (1997).
Interdisciplinary Research
MOUNTAIN, J. R., D. L. WANKUM, M. K. MAZUMDER, T. CHASSER, and P. PETTIT. Conf. Record 1997 IEEE Indus. Appl. Soc., 3, 1710-1715 (1997).
PALMORE, J. (ed.). SIMVAL '94. Proceedings of the Symposium on Simulation Validation (Military Operations Research Soc., 1997).
SIMS, R. A., M. K. MAZUMDER, X. LIU, J. R. MOUNTAIN, D. L. WANKUM, P. PETTIT, and T. CHASSER. Electrostatic effects on first pass transfer efficiency in the application of powder coatings. Conf. Record 1997 IEEE Indust. Appl. Soc., 3, 1697-1704 (1997).
Nondestructive Evaluation and Testing
REIS, H. L. M. DOS. Acousto-ultrasonic nondestructive evaluation of materials and structures. Invited paper, 134th Mtg., Acoust. Soc. of Amer. (San Diego, Calif., Dec. 1997).
REIS, H. L. M. DOS. Broken rail detection using remote sensing: air coupled transducers and laser generation of ultrasound. Wkshp. on Rail Defect Detection and Removal Policies and Broken Rail Detection (Transportation Technol. Center, Amer. Assn. of Railroads) (Pueblo, Colo., Jul. 1997).
REIS, H. L. M. DOS and K. A. WARMANN. Nondestructive evaluation of the residual life of steel belted radial truck tires. 8th Int. Symp. on Nondestructive Characterization of Mater. (Boulder, Colo., Jun. 1997).
Operations Research
DAVIS, W. J. An object-oriented simulator for flexible logistics. 1997 Army Operations Res. Symp. (Ft. Lee, Va., Nov. 1997).
DAVIS, W. J. A distributed object-oriented simulator for command and control. 1997 Army Operations Res. Symp. (Ft. Lee, Va., Nov. 1997).
DAVIS, W. J. A distributed intelligent control architecture for command and control. 1997 Army Operations Res. Symp. (Ft. Lee, Va., Nov. 1997).
Robotics
SPONG, M. W. and T. GROENEWALD. An experimental evaluation of Riemannian curvature based feedback linearization for a direct drive manipulator. IFAC-IFIP-IMACS Conf. on Contr. of Indus. Syst. (Belfort, France, May 1997) 643-647 (1997).
Vehicle Dynamics
RUHL, R. L. and K. GASTON. Favorable outcomes in highway accident litigation and settlement: the decisions start on-site. 1997 ATA Mgt. Conf. Exhibition (Las Vegas, Nev., Oct. 1997).
RUHL, R. L. and A. SIEVERS. The latest in accident investigation and reconstruction. Amer. Trucking Assn. Highway Accident Litigation Conf. (Monterey, Calif., Sept. 1997).
Control Systems
BISHOP, B. Intelligent visual servo control of an air hockey playing robot. Ph.D. thesis, Electrical and Computer Engr., M. W. Spong, adviser (1997).
Design and Manufacturing Systems
CHEN, T. Intelligent modeling and development of a flexible object-production planning simulator. M.S. project, W. J. Davis, adviser (1997).
GONZALEZ, F. G. Real-time distributed control and simulation of a physical emulator of a flexible manufacturing system. Ph.D. thesis, Electrical and Computer Engr., W. J. Davis and R. S. Sreenivas, advisers (1997).
Evolutionary Computation
HARIK, G. Learning linkage to efficiently solve problems of bounded difficulty using genetic algorithms. Ph.D. thesis, Electrical Engineering and Computer Science (Univ. of Michigan), D. E. Goldberg, adviser (1997).
HORN, J. The nature of niching: genetic algorithms and the evolution of optimal, cooperative populations. Ph.D. thesis, D. E. Goldberg, adviser (1997).
MILLER, B. L. Noise, sampling, and genetic algorithms. Ph.D. thesis, Computer Science, D. E. Goldberg, adviser (1997).
Integrated Mechanical and Structural Design
ERLER, N. Reliability study of the O'Brien lock and dam. M.S. thesis, B. Hall, adviser (1997).
Interdisciplinary Research
DAI, M. Iterated function systems, Hausdorff dimension and related topics. Ph.D. thesis, Mathematics, J. Palmore, adviser (1997).
NIAMSUP, P. Julia sets and symbolic dynamics of certain rational and entire functions. Ph.D. thesis, Mathematics, J. Palmore, adviser (1997).
STAJNER, I. Baker's transformation. Ph.D. thesis, Mathematics, J. Palmore, adviser (1997).
Nondestructive Evaluation and Testing
BARIGHT, M. D. Inspection of concrete bridge decks with asphalt overlays--a comparison of three nondestructive evaluation methods. M.S. thesis, H. L. M. dos Reis, adviser (1997).
COOK, B. Real-time tool condition monitoring in cold heading processes using an acoustic approach. M.S. thesis, Mechanical and Industrial Engr., H. L. M. dos Reis, adviser (1997).
GOLKO, P. J. Prototype acousto-ultrasonic machine for the nondestructive evaluation/characterization of damage in steel belted radial tires. M.S. thesis, Mechanical and Industrial Engr., H. L. M. dos Reis, adviser (1997).
HELIKER, G. J. Remote sensing-air coupled transducer and laser ultrasonics. M.S. project, H. L. M. dos Reis, adviser (1997).
NINNAN, N. NDT&E of ultrasonic welding and materials characterization. M.S. thesis, Mechanical and Industrial Engr., H. L. M. dos Reis, adviser (1997).
TIMMINS, J. S. NDT&E of adhesive bond strength in protective coatings. M.S. project, H. L. M. dos Reis, adviser (1997).
VOEGELE, A. C. Cold header process monitoring using a genetic algorithm designed neural network approach. M.S. thesis, H. L. M. dos Reis, adviser (1997).
Operations Research
DELIGIANNIS, W. J. Analysis of effectiveness of training programs for truck drivers. M.S. project, J. V. Carnahan, adviser (1997).
Scott A. Burns
NSF Presidential Young Investigator Award, 1989
Gamma Epsilon Teaching Excellence Award, Department of General Engineering, UIUC, 1989, 1990, 1992
Everitt Award for Teaching Excellence, College of Engineering, UIUC, 1990
Center for Advanced Study, Beckman Associate, UIUC, 1992
Engineering Council Advisors List for Outstanding Advising, UIUC, 1996
James V. Carnahan
Gamma Epsilon Teaching Excellence Award, Department of General Engineering, UIUC, 1986, 1991
Everitt Award for Teaching Excellence, College of Engineering, UIUC, 1989
Andersen Consulting Award for Excellence in Advising, College of Engineering, UIUC, 1990, 1991, 1992, 1993
Thomas F. Conry
Fellow, American Society of Mechanical Engineers
Osman Coskunoglu
Outstanding Dissertation of the Year Award, School of Industrial and Systems Engineering, Georgia Institute of Technology, 1979
Wayne J. Davis
Andersen Consulting Award for Excellence in Advising, College of Engineering, UIUC, 1990, 1993
Engineering Council Advisors List for Outstanding Advising, College of Engineering, UIUC, 1995
Jerry S. Dobrovolny, Emeritus
Fellow, American Association for the Advancement of Science
Life Member, American Society of Civil Engineers
Life Member, National Society of Professional Engineers
Award of Merit, National Advisory Council on Vocational Education, 1973
Illinois Award, Illinois Society of Professional Engineers, 1983
Distinguished Service Award, Illinois Society of Professional Engineers, 1986
Gamma Epsilon Distinguished Alumni Award, Department of General Engineering, UIUC, 1988
David E. Goldberg
Prater Exchange Professor, University of Alabama and National Taiwan University, 1986
Capstone Engineering Society Outstanding Research Award, University of Alabama, 1989-90
NSF Presidential Young Investigator Award, 1985-90
Distinguished Visiting Professor, ITESM, Monterrey, Mexico, 1990
Associate, Center for Advanced Study, UIUC, 1995-96
Wickenden Award, American Society for Engineering Education, 1996
Gambrinus Fellow, University of Dortmund, Germany, 1997
W. Brent Hall
Excellence in Teaching Award, Department of General Engineering, UIUC, 1995, 1997
Engineering Council Advisors List for Outstanding Advising, UIUC, 1995, 1996
Edward N. Kuznetsov
Gamma Epsilon Teaching Excellence Award, Department of General Engineering, UIUC, 1984, 1994
Juraj V. Medanic
Dusan Mitrovic Award for Best Paper in Control, ETAN (Yugoslavia), 1983
L. Daniel Metz
Everitt Award for Teaching Excellence, College of Engineering, UIUC, 1970
Ralph R. Teetor Award, Society of Automotive Engineers, 1972
Urbana-Champaign Campus Award for Excellence in Undergraduate Teaching, UIUC, 1977
Gamma Epsilon Teaching Excellence Award, Department of General Engineering, UIUC, 1983
Andersen Consulting Award for Excellence in Advising, College of Engineering, UIUC, 1988
Best Paper Presentation, Society of Automotive Engineers Passenger Car Meeting, 1989
Manssour H. Moeinzadeh
Ralph R. Teetor National Educational Award for Teaching Excellence, Society of Automotive Engineers, 1984
Centennial Recognition for Exceptional Contribution to American Society for Engineering Education and the Profession of Engineering, 1993
United Nations Development Programme Award for Collaborative Research and Educational Projects with Overseas Institutions, 1994 and 1995
Julian I. Palmore
Associate Fellow, American Institute of Aeronautics and Astronautics
American Rocket Society Award, 1960
Bernard Friedman Prize, University of California, Berkeley, 1973
Lilly Postdoctoral Teaching Award Fellow, Massachusetts Institute of Technology, 1974-75
Fellow, Center for Advanced Study, UIUC, 1979
Sigma Xi National Lecturer, 1989-91
Commander's Award for Distinguished Public Service, U.S. Army Construction Engineering Research Laboratory, 1991
Editor, PHALANX, The Bulletin of Military Operations Research, 1995-
Chair, Menger Prize Committee, American Mathematical Society, 1995-98
Director, Military Operations Research Society, 1996-2000
Chair, Warfare Analysis and Complexity Mini Symposium/Workshop, Johns Hopkins University, September 1997
MCAP Award, Military Operations Research Society, 1995, 1997
Michael H. Pleck
Everitt Award for Teaching Excellence, College of Engineering, UIUC, 1974
Campus Award for Undergraduate Teaching Excellence, UIUC, 1975
Champaign-Urbana Jaycees Outstanding Young College Educator Award, 1976-77
Ralph R. Teetor Award, Society of Automotive Engineers, 1980
Western Electric Fund Award, American Society for Engineering Education, 1983
Gamma Epsilon Teaching Excellence Award, Department of General Engineering, UIUC, 1987
National Computer Graphics Association, Micro CADD Academic Award, 1990
Joe B. Wyatt Challenge Award, Educom, 1991
Andersen Consulting Award for Excellence in Advising, College of Engineering, UIUC, 1991, 1993, 1994
Engineering Council Advisors List for Outstanding Advising, UIUC, 1995
Robert P. Larsen Human Development Award, 1996
Delta Sigma Omicron Distinguished Teaching Award, 1997
Henrique L. M. dos Reis
Fellow, British Institute of Non-Destructive Testing
Fellow, Acoustic Emission Working Group
Mark W. Spong
Best Paper Award, 1987 Robotics and Expert Systems Symposium
Fellow, Institute of Electrical and Electronics Engineers
Editor, IEEE Transactions on Control Systems Technology
R. S. Sreenivas
Research Initiation Award, National Science Foundation, 1994
Mark G. Strauss
Outstanding Biomedical Engineering Student Award for Teaching, Research, and Academic Standing, University of Texas at Arlington, 1985
Andersen Consulting Award for Excellence in Advising, College of Engineering, UIUC, 1990, 1994
Deborah L. Thurston
National Science Foundation Research Initiation Award, 1988
NSF Presidential Young Investigator Award, 1989
Andersen Consulting Award for Excellence in Advising, College of Engineering, UIUC, 1990, 1993, 1994
Xerox Award for Faculty Research, College of Engineering, UIUC, 1992, 1995
Eugene L. Grant Award for best paper of the year in The Engineering Economist (with A. Locascio), 1996
Louis Wozniak
Fellow, Institute of Electrical and Electronics Engineers
Gamma Epsilon Teaching Excellence Award, Department of General Engineering, UIUC, 1985
Andersen Consulting Award for Excellence in Advising, College of Engineering, UIUC, 1989, 1991, 1992, 1994, 1995
Energy Development and Power Generation Committee Prize Paper Award, International Joint Power Generation Conference, 1990
Energy Development and Power Generation Committee Prize Paper Award, International Joint Power Generation Conference, 1993
Engineering Council Advisors List for Outstanding Advising, UIUC, 1996