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Topher

I am a Ph.D. candidate in the Department of Mechanical Engineering at the Johns Hopkins University. I am a member of the Dynamical Systems and Control Laboratory under the direction of Professor Louis Whitcomb.

Resume

This page provides my perspective on my current achievements and professional goals. For a more "just the facts" presentation of my background, I encourage you to view a PDF of my Resume.

Research Overview

My current objective is to facilitate Unmanned Underwater Vehicle (UUV) scientific deployments by enabling these systems to better utilize their capacity for dynamic motion. To this end, my advisor and I are using a range of techniques from geometric mechanics and systems theory in the development of state/parameter estimation and control algorithms for submerged vehicles during dynamic operation. For example, we have developed a new angular velocity observer for a rotating rigid body (see the figure below for a sample from the preliminary analysis). Currently we are developing several UUV adaptive identification and adaptive control algorithms.

Simulation of an Angular Velocity Observer developed as part of my work at Johns Hopkins University. Note the convergence of the estimated angular velocity to the true value as time progresses.


Providing evidence which can convince scientists (and other end users) that theoretical contributions are worth the risks of deployment is not an easy task. Experimental evaluation must be used to show that new algorithms are both safe and will enable deep sea robotic interventions previously thought infeasible or impractical. The Dynamical Systems and Control Laboratory has a proven track record of developing this type of evidence using our Hydrodynamic Test Facility to quantify UUV performance gains (here is an article describing the Hydrodynamics Testing Facility). For example, this facility is well suited to testing the algorithms presented at the 2003 IFAC Workshop on Guidance and Control of Underwater Vehicles by Whitcomb et all. (A New Control System for the Next Generation of US and UK Deep Submergence Oceanographic ROVs). Currently I am using the facility to characterize parameter estimation performance and will soon move to testing adaptive control algorithms. The figure below shows the facility during one of my recent adaptive identification experiential evaluations. My work with this facility over the past half-decade has not only allowed me to become comfortable with its operation, but also to play a key role in vehicle maintenance and vehicle upgrades (including its electrical, mechanical and software subsystems). For example, I took part in an experimental redevelopment of the JHUROV control software. The results of this redevelopment are featured in this video.

The Hydrodynamic Test Facility during an Adaptive Identification experiment. This algorithm finds parameters which model the JHUROV's performance during dynamic operation.

My metric for success as a researcher has been (and will continue to be) creating useful developments for deep-sea UUV deployments. Therefore, I have participated in every possible opportunity to work with UUVs in the open ocean. These opportunities were available from my internship with Anadarko Petroleum Company's Worldwide Deepwater Operations Group and my lab's collaborations with Woods Hole Oceanographic Institution (WHOI). For example, in 2011 I deployed to the mid Atlantic for an engineering cruise with WHOI's UUV Nereus. The figure below is a picture of me with the vehicle. During this work I supervised autonomous vehicle operation using an acoustic vehicle-to-ship link, retasked the vehicle through this acoustic link based on changing mission parameters, helped maintain the vehicle, and helped post process the vehicle's mission data.

Me with Nereus at the end of the June 2011 deployment.

Future Directions

After I finish my PhD there are several directions I am interested in pursuing:

Deployment Design/Project Management During my time at Johns Hopkins University I have developed a UUV skill set through my time utilizing our Hydrodynamic Test Facility; I am interested in pursuing opportunities which allow me to use these skills to solve real world problems in the open ocean. For example, I would be interested in managing projects which require effective use of off-the-shelf ROV/ AUV systems or working as part of a team to accomplish difficult intervention missions.

Collaborative Control Techniques During my 2007 summer internship with the Adaptive Robotics Group at Idaho National Laboratory I was introduced to collaborative control techniques for remotely controlling land based robotic vehicles. That experience convinced me control methods designed to intelligently shuffling the strengths of the human operator with autonomous algorithms have the potential to significantly outperform both autonomous operation and teleoperation. The constraints of working in the deep ocean promise to allow even greater collaborative control performance gains and I would pursue any opportunity to research this topic in that problem domain.

UUV System Science Developments A number of the results we are developing at Johns Hopkins University are the simplifications of more difficult research questions; I am very interested in pursuing these questions past their simple starting points. Therefore, continuing my work developing UUV control, navigation and state estimation capabilities is of interest to me, as are opportunities to develop mission specific UUVs.

Education

Ph.D. Mechanical Engineering, Johns Hopkins University, expected Summer 2013
B.S. Mechanical Engineering, Washington University in St. Louis, 2007
B.A. Physics, University of Puget Sound, 2007

Publications

C. J. McFarland and L. L. Whitcomb. Adaptive model-based control for underwater vehicles: Theory and experimental evaluation in the presence of unmodeled actuator dynamics,” Johns Hopkins University, Tech. Rep., 2013.

C. J. McFarland and L. L. Whitcomb. A New Adaptive Identifier for Inertial Parameters of Robotic Manipulators. IEEE Transactions in Robotics. In Preparation

C. J. McFarland and L. L. Whitcomb. A New Adaptive Identifier for Inertial Parameters of Rotational Plants. In Proceeding of the IEEE/MTS Oceans 2012, Hampton Roads, VA October 26-29.

G. Troni, C. McFarland, K. Nichols, L. L. Whitcomb. Experimental Evaluation of an Inertial Navigation System for Underwater Robotic Vehicles. In ICRA 2011, Shanghai, China, September 2011.

D. I. Gertman, C. J. McFarland, T. A. Klein, A. E. Gertman, and D. J. Bruemmer. A methodology for testing unmanned vehicle behavior and autonomy. In Proceedings of the 2007 Workshop on Performance Metrics for Intelligent Systems, PerMIS ’07, pages 62–69, New York, NY, USA, 2007. ACM.

Awards and Honors

Fellowships

Contact Information

223 Latrobe Hall
3400 N. Charles Street
Baltimore, MD 21218 USA
cmcfarland@jhu.edu
410-516-8021 (Office & Hydrodynamic Test Facility phone)
410-516-4316 (fax)

This page was last modified on 20 September 2013, at 14:33.