Experience

Scientist IX
General Atomics
Electromagnetic Systems
October 2021 -- Present

Principal Scientist
QinetiQ Inc.
350 Second Avenue 
Waltham, MA 02451-1196
July 1998 -- August 2021

Projects Include:

• Chief Engineer for military vehicle electric drive program
• Chief Engineer for Small Robot Program of Record
• Wound field flux switching machines for use as high-speed generators and as motors for electric vehicles.
• Energy harvesting, metrology, and modeling and simulation for Smart-Grid Sensors.
• Launch motor controls lead for the Electromagnetic Aircraft Launch System (EMALS) System Functional Demonstration (SFD) system, subcontracting to General Atomics. This phase involved the design, construction, and test of a shipboard-ready linear motor capable of catapulting aircraft off the decks of Navy carriers. [press release][Video]
• Magnetic Actuator design and system model for the Phase II SBIR, Development of a micro-pumped cryogenic two-phase heat transport system.
• Motor design and controller development for the EMALS Program Definition Program Definition phase, subcontracting to General Atomics. The PDRR phase culminated in the successful deadload testing of a full-scale prototype linear motor system at NAES Lakehurst. [article][mov]
• Controller development for the Navy’s Advance Arresting Gear (AAG) program, subcontracting to General Atomics.
• Design of synchronous PM linear motor, electrodynamic "null-flux" suspension, and eddy current brake for NASA's Maglifter program. This project involved the successful design and construction of a bearingless motor that accelerates 6 kg mass to a speed of 55 mph over the length of a 20 foot drive section.  [avi]
• Design of slotless axial flux linear induction motors for the Navy Electric Aircraft Recovery System (EARS) Phase II SBIR. This project involved the successful design, construction, and testing of a scale model arrestor system for Navy aircraft carriers. This system accelerates a 100 lb. mass to a speed of approximately 25 mph using an air cannon. The mass then hooks onto a cable, either end of which is connected to a vector controlled linear induction motor. By applying carefully controlled forces to the ends of the cable, the mass is brought to a halt.  [avi]
• Creation and implementation of a model-based reasoning algorithm for power system reconfiguration for the Navy Nonlinear Power Systems Phase II SBIR.  
• Analysis of an electrodynamic suspension for a rocket sled, done as a subcontractor to General Atomics' Holloman High Speed Test Track Upgrade program. 
• Design of a block-switched linear transformer intended to supply field excitation for a large linear synchronous machine under the Navy Phase I SBIR, Electric Power Transfer. 

Independent Consultant
Brighton, MA
August 1997 -- July 1998

Design and analysis of novel electric machines. Projects included:

• Created a full-featured finite element package for the solution of 2D planar and axisymmetric problems in low frequency magnetics under Windows. [Download]
• Testing of a Hybrid PM Generator for SatCon.  
• Creation of a Win95/98/NT program for the weight-optimal design of magnetic bearings for gas turbine engines for SatCon.  
• Analysis of a Homopolar PM Bias magnetic bearing system for Avcon.  
• Design of passive magnetic bearings and eddy current dampers for energy storage flywheels for Beacon Power.  

Research and Development Engineer
SatCon Technology Corporation
161 First Street
Cambridge, MA 02142-1221
July 1996 -- July 1997

Design and analysis of novel electromechanical machines; Design and implementation of multiple input/multiple output controllers. While at SatCon, work included:

• Design of magnetic bearings for energy storage flywheels including both active and passive magnetic bearings.  
• Design of magnetic bearings for gas turbine engines. These designs focused on achieving the low bearing losses and high speeds possible with magnetic bearings while tolerating the extremely high temperatures present in gas turbine engine cores. Severe constraints on bearing size and weight are also driving considerations in these designs.  
• Principal Investigator for a precision positioning system for silicon photolithography. Designed Lorentz actuators employed by the system, and wrote C code implementing a 1400 Hz, three degree-of-freedom control loop yielding positioning accuracy of +-50 nm.  
• Design of a 10 kW hybrid PM alternator. The alternator is excited via permanent magnets but has an additional stationary field coil that can be used to regulate output voltage. The alternator was modeled both analytically and via a custom finite element program that was required to account for the alternator's intrinsically three-dimensional flux paths. This work was patented as US6097124 
• Authoring of several SBIR grant proposals relating to magnetic bearings, dynamics, and controls.  

Research Assistant
University of Virginia
Department of Mechanical, Aerospace and Nuclear Engineering
August 1990 -- May 1996

While at the University of Virginia, work included:

• Design and construction of a six degree of freedom large-gap magnetic actuator to be used as an experimental apparatus for the study of vortex breakdown in fluids. Work sponsored by NSF.  
• Development of a hybrid analytical/finite element model of the effects of eddy currents, flux leakage, and fringing in magnetic bearings. Work sponsored by Kingsbury, Inc.  
• Derivation of a general method for the control the Magnetic Stereotaxis System, a large-gap magnetic actuator used to perform neurosurgery. Work done in conjunction with the Department of Physics, University of Virginia.  
• Design of passive magnetic bearings for use in an artificial heart.  
• Development of fault-tolerant magnetic bearing control strategies. Work sponsored by the Mobil Corporation.  
• Investigation of the feasibility of the use of neural networks in automobile collision prediction. Work sponsored by the National Highway Transportation Safety Administration.

Education

Doctor of Philosophy, Mechanical and Aerospace Engineering, May 1996
University of Virginia, School of Engineering and Applied Science, Charlottesville, VA

Dissertation: Optimal solutions to the inverse problem in quadratic magnetic actuators.

Abstract: The formulation of current-to-force relationships for magnetic actuators proceeds in a fairly straightforward fashion from Maxwell's equations for magnetostatic problems. However, the inverse problem of determining a set of currents to realize a desired force is less well understood. Historically, this problem has been relatively neglected because actuators were built in symmetric geometries where a viable solution could be intuited. Recently, calls for both optimal actuator performance and fault tolerance have necessitated the formulation of general solution methodologies for magnetic actuators. This work will consider such formulations for magnetic actuators whose current-to-force relationships are homogeneous quadratics. This class of actuators includes active magnetic bearings and the magnetic stereotaxis system.

Advisor: Eric H. Maslen

Master of Science, Mechanical and Aerospace Engineering, May 1993
University of Virginia, School of Engineering and Applied Science
Thesis: Pre-crash sensing and restraint optimization for automobiles.

Advisor: Eric H. Maslen

Bachelor of Science, Mechanical Engineering, May 1990
Duke University, School of Engineering, Durham, NC

Cum Laude

Publications

D. Meeker and E. Maslen, "A Parametric Solution to the Generalized Bias Linearization Problem", Actuators. 9(1):14, Mar. 2020. https://doi.org/10.3390/act9010014

D. Meeker, N. Bianchi, J. Gyselinck, R. V. Sabariego, L. Alberti, G. Pellegrino, and F. Cupertino, "Electrical machine analysis using free software", in 2017 IEEE Energy Conversion Congress and Exposition (ECCE 2017), Oct. 1-5 2017, pp. 1– 289.

D.C. Meeker, "A Generalized Unbiased Control Strategy for Radial Magnetic Bearings," Actuators, 6(1):1, Jan. 2017.

D.C. Meeker, "Series-Wound Heteropolar Inductor Motor for Automotive Applications," IEEE Transportation Electrification Conference (ITEC 2016), Dearborn, MI, June 27-29, 2016. [Poster]

D.C. Meeker, "Improvised asymptotic boundary conditions for electrostatic finite elements," IEEE Transactions on Magnetics, 50(6):7400609, June 2014.
http://dx.doi.org/10.1109/TMAG.2014.2300196

D.C. Meeker, "Doubly Salient Synchronous Generator for Gas Turbine Engines," Electric Machines Technology Symposium (EMTS 2014), Villanova, PA, May 28-29, 2014.

D.C. Meeker, "Improvised open boundary conditions for magnetic finite elements," IEEE Transactions on Magnetics, 49(10):5243-5247, Oct. 2013.
http://dx.doi.org/10.1109/TMAG.2013.2260348

D.C. Meeker, "An improved continuum skin and proximity effect model for hexagonally packed wires," Journal of Computational and Applied Mathematics, 236(18):4635-4644, Dec. 2012. http://dx.doi.org/10.1016/j.cam.2012.04.009

D.C. Meeker and M. J. Newman, "Indirect vector control of a redundant linear induction motor for aircraft launch," Proceedings of the IEEE, 97(11):1768-1776, Nov. 2009.

D.C. Meeker and E.H. Maslen, "Analysis and Control of a Three Pole Radial Magnetic Bearing," Tenth International Symposium on Magnetic Bearings, Martigny, Switzerland, Aug. 2006.

D.C. Meeker, A.V. Filatov, and E.H. Maslen, "Effect of Magnetic Hysteresis on Rotational Losses in Heteropolar Magnetic Bearings," IEEE Transactions on Magnetics, 40(5):3302-3307, Sept. 2004.

J. Dill and D. Meeker, Maglifter tradeoff study and subscale system demonstrations, NASA report NAS-98069-1362, Dec. 2000.

D.C. Meeker and E. H. Maslen, "Prediction of rotating losses in heteropolar radial magnetic bearings," Journal of Tribology, 120(3):629-635, July 1998.

D. C. Meeker, E. H. Maslen, and M. D. Noh, "An augmented circuit model for magnetic bearings including eddy currents, fringing, and leakage," IEEE Transactions on Magnetics, 32(4):3219-3227, July 1996.

D. C. Meeker, E. H. Maslen, R. R. Ritter, and F. M. Creighton, "Optimal realization of arbitrary forces in a magnetic stereotaxis system," IEEE Transactions on Magnetics, 32(2):320-328, March 1996.

E. H. Maslen and D. C. Meeker, "Fault-tolerance of magnetic bearings by generalized bias current linearization," IEEE Transactions on Magnetics, 31(3):2304-2314, May 1995.

D. C. Meeker and M. A. Townsend, "Motions of a powered top with a spherical tip on a curved surface," Shock and Vibrations Journal, 2(1):23-32, Jan. 1995. [exe]

D. C. Meeker and D. M. Dozor, "Thermomagnetic optimization of solenoidal magnetostrictive actuators," SPIE 6th Annual International Symposium on Smart Structures and Materials, Newport Beach, CA, March 1999.

D. C. Meeker, E. H. Maslen, and M. Kasarda, "Influence of actuator geometry on rotating losses in heteropolar magnetic bearings," Sixth International Symposium on Magnetic Bearings, Cambridge, MA, Aug. 1998.

D. C. Meeker and E. H. Maslen, "A thin plate model of rotating losses in magnetic bearings," Fifth International Symposium on Magnetic Bearings, Kanazawa, Japan, Aug. 1996.

D. C. Meeker and E. H. Maslen, "Power optimal solution of the magnetic inverse problem for heteropolar magnetic bearings," Fifth International Symposium on Magnetic Bearings, Kanazawa, Japan, Aug. 1996.

D. C. Meeker, E. H. Maslen, and M. D. Noh, "A wide bandwidth model for the electrical impedance of magnetic bearings," Third International Symposium on Magnetic Suspension Technology, Tallahassee, FL, Dec. 13-15, 1995.

E. H. Maslen and D. C. Meeker, "Bias linearization and decoupling for active magnetic bearings: a generalized theory," Fourth International Symposium on Magnetic Bearings, Zurich, Switzerland, 1994.

D. C. Meeker and M. A. Townsend, "Motions of a powered top with a spherical tip on a curved surface," ASME Winter Annual Meeting, New Orleans, LA, 1993.

Patents

US2020/0346699: Method of traversing difficult terrain. Inventors: Meeker, D. et al. Assignee: Foster-Miller. Filing Date: Apr. 30, 2020

US2020/0114529: Remotely controlled packable robot. Inventors: Meeker, D. et al. Assignee: Foster-Miller. Filing Date: Oct. 7, 2019

US11034015: Remotely controlled packable robot. Inventors: Meeker, D.; Mason, T.; Kirouac, A.; Wasserman, R. Assignee: Foster-Miller. Filing Date: Jul. 11, 2019

US10471589: Remotely controlled packable robot. Inventors: Meeker, D.; Mason, T.; Kirouac, A.; Wasserman, R. Assignee: Foster-Miller. Filing Date: Sept. 14, 2017

US10414039: Remotely controlled packable robot. Inventors: Meeker, D.; Mason, T.; Kirouac, A.; Wasserman, R. Assignee: Foster-Miller. Filing Date: Sept. 14, 2017

US10331132: Remotely controlled robot. Inventors: Meeker, D.; Mason, T.; Wiesman, R. Assignee: Foster-Miller. Filing Date: June 9, 2017

US2016/0370408: Weather resistant ungrounded power line sensor. Inventors: Meeker, D.; Berglund, J.; Mason, T.; Murphree, M.; Post, A.; Godfrey, J. Assignee: Foster-Miller. Filing Date: June 22, 2015

US10075051: Series-wound heteropolar inductor motor. Inventor: Meeker, D. Filing Date: March 16, 2015

US9347972: Alternate voltage sensing method for increased weather robustness of ungrounded power line sensors. Inventors: Meeker, D.; Compter, B. Assignee: Foster-Miller. Filing Date: March 25, 2013

US9293952: Wound field flux switching machine with sinusoidal back electromotive force. Inventor: Meeker, D. Assignee: Foster-Miller. Filing Date: March 25, 2013

US9347976: Hot Stick Power Analyzer. Inventors: Mason, T.; Meeker, D; Godfrey, J; Travis, J; Leary, W; Post, A Assignee: Foster-Miller. Filing Date: October 23, 2013

US9027454: Ground Pressure Detonation Device. Inventors: Wiesman, R; Kirouac, A; Meeker, D; Berglund, J; Tavernini, M. Assignee: Foster-Miller. Filing Date: October 25, 2012

US2005/0147512: Rotary pump with electromagnetic LCR bearing. Inventors: Chen, Hsiang Ming; Smith, William A.; Vitale, Nicholas G.; Chapman, Peter A. JR.; Donahue, Arthur C.; Meeker, David C. Assignees: Foster-Miller, Inc.; The Cleveland Clinic Foundation. Filing Date: July 7, 2005

US6097124: Hybrid permanent magnet/homopolar generator and motor. Inventors: Rao, Gita P.; Kirtley, James L.; Meeker, David C.; Donegan,Kevin J. Assignee: Satcon Technology Corporation. Filing Date: August 1, 2000

Affiliations

Member, Institute of Electrical and Electronics Engineers