Lawrence L. ("Larry") Hoberock

Professor and Department Head
School of Mechanical and Aerospace Engineering

Note:  For information concerning admissions issues, application materials and forms, financial aid, or other questions on the Graduate Program in the School of Mechanical and Aerospace Engineering, please use the following addresses:

E-mail:  maeacad@okstate.edu

Regular Mail:
Graduate Program Director
School of Mechanical and Aerospace Engineering
218 Engineering North
Oklahoma State University
Stillwater, OK 74078

Such correspondence addressed to L.L. Hoberock's personal e-mail or regular mail addresses, will result in either no response or very long delays in receiving information and assistance.
 

Academic Background

Ph.D., Purdue University
M.S., Mechanical Engineering, Purdue University
B.S., Mechanical Engineering, University of Missouri-Rolla

Areas of Interest

Dynamics and Control of Mechanical and Electromechanical Systems
Robotic and Machine Vision Systems
Machine Design
Vibrating Screen Technology
Drilling Mechanics

Listed In

American Men & Women of Science
2000 Outstanding Scientists of the 20th Century, 2nd Edition
Who's Who in the World
Who's Who in America
Who's Who in America – Science and Engineering
Who's Who in the South and Southwest

Current and Recent Projects

Robot Design for Large, Automated Dishwashing Operations – Large commercial dishwashing operations handle upwards of 15,000 dish pieces per day with manual labor in poor working conditions. Operating costs and labor turnover are high. Techniques are sought to automatically load, unload, sort, and inspect a wide variety of dish pieces for flight-type automatic dish washers. This involves selection and integration of a suitable robotic arm, design and construction of a material handling system and robotic end effectors, programming robot motions, developing machine vision sorting and inspection software, and integrating these with a machine vision system for fast, adaptable, and efficient automatic dish handling.

Silverware Separation, Sorting, and Inspection – Technology and prototype development is underway to process cleaned, mixed silverware pieces washed in batch mode by a high-volume commercial automatic dish washers. The goal is for individual pieces to be automatically separated from the batch after washing and then sorted and inspected by machine vision and automated sorters. Special challenges are to design and construct a high speed, efficient mechanical separator; design, program, and implement machine vision sorting and inspection software; integrate the separation, sorting, and inspection into a single working prototype; and add modular enhancements, such as napkin wrapping..

Enlarged Region Stabilizing Control of Nonlinear Dynamic Systems – Linear controllers are often used to stabilize complex nonlinear systems in a region where a linear approximation of the nonlinear system is valid.  Typically, the extent of this region is not predictable, and the stabilized attractive region is often unsatisfactorily small.  For uncertain nonlinear systems, we seek methods to design both linear and nonlinear robust controllers to substantially enlarge the attractive region over those obtained from linearization.  Systematic procedures are sought for generating suitable controllers given uncertainty specifications for the system.  Lyapunov-based design strategies are employed in developing new methodologies, while incorporating so-called “intelligent” techniques, including neural networks, genetic programming, and genetic algorithms.  Benchmark nonlinear systems are used to compare different controller design strategies.

Flow Through Vibrating Screens – Drilling fluids and industrial slurries are often passed through vibrating screens to either separate solids from liquids or to grade the solids.  The rheologies of such fluids are usually characterized by power law or Bingham plastic models.  Methods are sought to easily characterize the fluid-handling properties of the screens such that performance of different screen designs can be compared.  While there is evidence that such characterization can be accomplished for low velocities of fluids through the screens, almost no work has been done for large fluid velocities.  Comparison and validation of analytical results with experimental data is an integral part of this program.

Professional Experience

Professor and Head, School of Mechanical and Aerospace Engineering, Oklahoma State University, June 1987–present
Independent Consultant, Buffalo, New York, December 1986–May 1987
Vice-President, Research and Development, Derrick Manufacturing Corp., Buffalo, New York, July 1985–November 1986
Research Supervisor I, Amoco Production Company, Tulsa, Oklahoma, Evanston, Wyoming, April 1983–June 1985
Research Supervisor II, Amoco Production Company, Tulsa, Oklahoma, June 1981–March 1983
Research Associate, Amoco Production Company, Tulsa, Oklahoma, September 1978–May 1981
Consultant, Amoco Production Company, Tulsa, Oklahoma, June 1977–August 1978
Associate Professor (tenured)/Assistant Professor, The University of Texas, Austin, August 1968–May 1977
Research Coordinator, U.S. Army Ballistic Research Labs, Aberdeen Proving Ground, Maryland, August 1966–August 1968
Research Engineer, Arnold Air Force Station, Tennessee/Aro, Inc., June 1964–September 1964
Research Engineer, Hamilton-Standard, Inc., Windsor Locks, Connecticut, June 1963–September 1963

Professional Affiliations

American Society of Mechanical Engineers (ASME), 1969–present

Fellow, 1992–present

Vice President, Systems and Design Group, 1999–2002

Knowledge and Community Groups

    1 of 4 Members, Blue Ribbon Selection Committee for 5 ASME Vice Presidents, 2005

Council on Engineering:

Chair, Nominating Committee, 1999–2002
Member of the Council, 1999–2002

Board on Engineering Education:

National M.E. Department Heads Committee: Chairman 1997–1998, Vice Chair 1996–1997, Secretary 1995–1996
Member-Planning and Organizing Committee, ASME M.E. Dept. Heads Conference, 1998-2000, 1994–1997, 1993–1993
Region X M.E. Department Heads:  Chairman, 1993–1995, V. Chair, 1992–1993, and Secretary, 1991–1992

Board on Research and Technology Development:

Member-Board Committee on Technology Development, 1995–1999
Member-Executive Committee, 1993–1995

Systems and Design Technical Group:

ASME Director, American Automatic Control Council, 1994–1996

Dynamic Systems and Control Division:

Honors Committee: Chair, 1998–1999; Vice Chair, 1996–1998; Member, 1993–1999
Division Executive Committee: Chair, 1990–1991, Member, 1988–1993, Chairman, Long-Range Planning, 1998–1990
Program Chairman-1974 ASME Winter Annual Meeting
Associate Editor, ASME Transactions, Journal of Dynamic Systems, Measurement, and Control, 1974–1977

American Automatic Control Council (AACC), 1994–1996

Member-Control Engineering Practice Award Committee, 1998–1999  
Director-ASME, 1994–1996

American Institute of Aeronautics and Astronautics (AIAA), 1989–present

Society of Petroleum Engineers (SPE), 1978–present

Drilling Review Chairman, 1988–1990 and Associate Editor, 1987–1988, SPE Journal of Petroleum Technology and SPE Drilling Engineering
Member, Technical Program Committee, 61st Technical Conference, 1986; Joint SPE/IADC Drilling Conference, 1986–1987

American Society of Engineering Education (ASEE), 1971–1978; 1987–present

Member, Executive Committee, AE Division, 2003-Present
Chair, Awards Committee, M.E. Division, 2002-2003
Member, Executive Committee, M.E. Division, 1993–1995
Member, Awards Committee, ME Division, 1988–1991, 1994–1997, 2001–2003
Director, Educational Research and Methods Division, 1974–1975 

IEEE Control Systems Society and Robotics and Automation Society, 1993–present

Industrial Member, Advisory Committee on Interdisciplinary Fluid Mechanics Research, The University of Texas, Austin, 1984–1985

Registrations

Registered Professional Engineer, Texas, #3142
Registered Professional Engineer, Oklahoma, #11356

Selected Publications

"Using Robust Stability Analysis Theorems For Robust Controller Design" (with P. Ngamsom), ASME Journal of Dynamic Systems, Measurement, and Control, Vol. 125, December 2003.

"Dynamic Differential Pressure Effects on Drilling of Permeable Formations" (with G. Bratcher), ASME Journal of Energy Resources Technology, Vol. 120, June 1998.

"Machine Vision Fuzzy Object Recognition and Inspection Using a New Fuzzy Neural Network" (with B. Chen), 1996 IEEE International Symposium on Intelligent Control, Dearborn, MI, Sept 15-18, 1996.

"Machine Vision Recognition of Fuzzy Objects Using a New Fuzzy Neural Network" (with B. Chen), 1996 IEEE International Conference on Robotics and Automation", Minneapolis, MN, April 22-28, 1996.

"A New Approach For Determining In-Situ Rock Strength While Drilling" (with G. Bratcher), ASME Journal of Energy Resources Technology, Vol. 118, December 1996.

"Fuzzy Logic Controller for Automatic Vision Parameter Adjustment in a Robotic Dish Handling System" (with B. Chen), 10th IEEE international Symposium on Intelligent Control", Monterey, CA, Aug. 27-29, 1995.

"A Modified Artmap Network, With Applications to Scheduling of a Robot-Vision Tracking System" (with K. Feng", 1992 ASME Winter Annual Meeting, Anaheim, CA, Nov. 8 - 13, 1992. In press, ASME Trans., J. of Dynamic Systems, Measurement, and Control.

"Fluid Conductance and Separation Characteristics of Oil field Screen Cloths," Fluid/Particle Separation Journal, Vol. 4, No. 2, June, 1991.

"Solids Conveyance Dynamics and Shaker Performance" (with. M. Lal). SPE # 14389, 60th Annual Technical Conference and Exposition of the SPE, Las Vegas, NV, Sept. 22-25, 1985. Also published in SPE Drilling Engineering, Dec. 1988.

"Solids Conveyance Dynamics and Shaker Performance" (with M. Lal), SPE Drilling Engineering, pp. 385-394, December 1988.

"Flow Limits in Vibrating Screen Separation of Drilling Fluids." Filtration and Separation, pp. 109-114, March/April 1982.

"Pressure Dynamics in Wells During Gas Kicks, Part I--Fluid Line Dynamics," (with S. R. Stanbery), Journal of Petroleum Technology, pp. 1357-1366, August 1981.

"Pressure Dynamics in Wells During Gas Kicks, Part II--Component Models and Results," (with S. R. Stanbery), Journal of Petroleum Technology, pp. 1367-1378, August 1981.

"A Study of Vibratory Screening of Drilling Fluids," Journal of Petroleum Technology, pp. 1889-1202, November 1980.

"A Survey of Longitudinal Acceleration Comfort Studies in Ground Transportation Vehicles." ASME Transactions, Journal of Dynamic Systems, Measurement, and Control, Vol. 99, No. 2, June 1977.

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