| Introduction | Objectives | Qualifications | Skills | Professional Experience | Education |
|---|---|---|---|---|---|
| Publications | Patents | Back to the main page ... | |||
|
|---|
Allows me to mentor a small team of less experienced engineers.
Has a strong physical and signal processing content.
Has as it's goal a product or set of products that makes the the world a little bit better.
Twenty two years industrial research experience. Proven ability to contribute to multiple phases of research projects, from physical measurements and mathematical modeling, signal processing and algorithm design, to market analysis for new technologies. A track record of identifying technological trends, past, present, and future. A prolific inventor who knows how to turn technical insights into intellectual property (12 out of 25 filed patent applications granted so far).
Areas of technical expertise: servo control of precision mechatronics, including storage and instrumentation systems. Adaptive filtering and control, nonlinear systems, phase-locked loops, demodulation & synchronization, optimal control and estimation, PID controllers, measurements, instrumentation, measurement automation, real-time systems, and signal post-processing. Expertise in implementing algorithms to minimize latency in real time systems.
Computer Languages: C/C++, Pascal, Perl, DSP, Visual Basic, FORTRAN, 80X86 ASM. Fluent in HTML. Knowledge of Perl, JavaScript, Java, XML, and Microsoft .NET. Expertise with FPGA and DSP implementation of sophisticated filtering and control algorithms. Comfortable across multiple computer platforms: Windows, Linux/Unix, MS-DOS, Mac-OS, and real time systems. Local expert in several modeling, simulation, and design environments including Matlab, Simulink, and VEE. Created and taught two internal classes on Matlab.
Professionally active. Frequent publisher at controls conferences and journals. Senior Member of the IEEE. Chair of IEEE CSS History Committee. As Vice Chair for Industry and Applications of the 2004 American Controls Conference (ACC), recruited a record number of tutorial sessions. Vice Chair for Workshops at the 2006 ACC and Special Sessions at the 2007 ACC. Vice Chair for Industry and Applications for the 2009 ACC. Program Chair of the 2013 ACC. Winner of the 2003 IEEE Control Systems Magazine Outstanding Paper Award.
An excellent communicator. Have taught multiple internal classes both at Agilent and at HP. My tutorial paper on PLLs gets frequently downloaded from my external web site and has been used by several professors in their controls classes. Industrial mentor for several graduate students from top universities. Frequent invited speaker at universities. Fluent in French, passable in Spanish.
Contributor to the workplace infrastructure. Host and organizer of an extremely popular series of technical Chalk Talks. Originator of idea behind Agilent Labs Academy, an internally generated training group at Agilent Labs. Member of the Agilent Labs Academy board and instructor for two Matlab classes. Member of the mentoring task force.
Professional Expertise:
Technical Skills:
Computer Languages: C/C++, Pascal, Perl, Visual Basic, FORTRAN, TMS DSP and 80X86 Assembly Language, VHDL.
Real Time Implementation: μProcessor, DSP, & FPGAs
Knowledge Of: Perl, JavaScript, Java, XML, and Microsoft .NET.
Modeling/Design Tools: Local Matlab and Simulink expert. Matlab/C interface. Matlab/VEE interface. Ojbect oriented Matlab and C++ programming.
Communication Skills:
Professionally Active:
Principal Project Engineer at Agilent Laboratories, Palo Alto & Santa Clara, CA, 8/04-present:
Servo engineer for Agilent Labs atomic force microscope (AFM) project. I have been working on control issues for improving atomic force microscopes, both from a performance and a usability perspective. My analysis of the effect of time delay on the closed-loop performance of the AFM control system was justification for new analog IO hardware for our test system. My analysis of the utility of state space methods led to 4 patent applications. I implemented a combination of on-line and off-line identification methods to allow nearly automatic tuning of the AFM control system (another patent application). I have implemented sophisticated demodulation algorithms in FPGA to improve the performance of non-contact AFM methods. I have restructured filtering operations to minimize their latency and allow for greater closed-loop bandwidth. I have brought methods from oscilloscopes into the decimation of AFM images and have generated several methods of using non-raster scan methods for AFMs (two patent applications). Recent work has allowed automation of the gain selection in the control system based on user criteria for minimum gain and/or phase margins, as well as maximum closed-loop ringing. So far, 16 invention disclosures (and from these 7 patent applications) based on my work in this area have been filed. Recently, I have set up collaborations with several professors in academia to further this work. I have helped raise the profile of my company in the AFM space by co-organizing an AFM control tutorial session at the 2007 American Control Conference and by co-organizing a full day of AFM control sessions at the 2008 American Control Conference. At the latter, I presented a method of increasing the bandwidth of a simple AFM PID controller by using it as an inverse dynamics filter.
Apart from the direct control work, I worked on an early GUI for the system and on extensive post processing of the scan data. I both debugged other engineers' FPGA code and written my own to implement advanced control functions. I wrote communications interfaces between the FPGA and Matlab, making possible large data block transfers between the two. I have written extensive Matlab code to automate measurement processing and control design
In this time, I was a founding board member for the Agilent Labs Academy, an internal training program based largely on a white paper that I wrote in 2003. The Academy board was awarded a unit level Ned Barnholdt Award for Innovation by Agilent in 2005. I have also generated and taught both introductory and intermediate level Matlab classes for this program, and am now the technical lead on the board.
| Top of this item | Back to the table of contents ... |
Principal Project Engineer at Agilent Laboratories, Palo Alto, CA, 4/00-8/04:
Conducted research on measurement systems for high-speed optical communications. I completed a digital front end to do data collection system for high-speed optical pulse sampling. This digital design streams data from the ADCs through a FPGA board to a host PC. This is complicated by the fact that the sampling scope nature of the system means that any stoppage in data collection due to slowness of the transfer of data to the host PC must be accounted for less the measurement data become meaningless. I came up with several innovative ways to maximize the use of the available PCI bus bandwidth by parallelizing the data streams. The buffers also had to contain information about when sampling might have been stopped so that the data stream could be meaningfully reconstructed on the PC. Upon completing this, and before my transfer to another project, I completed a 50+ page report detailing the design and operation for the remaining team members and supported them for several months after that.
Prior to this I worked on a way of making instrument data more accessible to users and on analysis and simulation of high speed phase-locked loop designs for jitter analysis, each of which lead to patent applications. I built a custom, modular time domain PLL simulation tool in C++ and Matlab. Class libraries of different phase detectors, oscillators, circuit components, and delay elements were constructed, allowing for a modular simulation of a wide variety of loops. The inherent stiffness of the PLL simulation problem was overcome by allowing multiple time scales within different parts of the loop. The simulation could directly import filters generated in Matlab and could save data back to Matlab files. This tool allowed the team to look at a variety of loop types, plus observe the effect of data on phase error and jitter. Post processing algorithms that I wrote allowed a single long simulation to be analyzed using a variety of filtering schemes.My initial work at Agilent Labs was in creating technology for a prototype of Agilent's first 40 Gbps Bit Error Ratio Tester, granted Test and Measurement World's 2003 Best in Test Award. I worked on software to identify and synchronize multiple parallel channels (US Patent # 6961317). I wrote software for building telecom standard compliant memory based test data that was directly ported into the product by the division (US Patent # 6973599). Finally, I worked on algorithms to dramatically improve the generation of eye error maps from BER measurements (US Patent # 6745148).
In my time at Agilent Labs, I have been co-organizer of a highly successful internal technical talk series, known simply Chalk Talks. Both at Agilent and HP Labs, I was involved in setting up the internal mentoring program, porting a constrained optimization algorithm to Matlab to fairly match mentees and mentors.
| Top of this item | Back to the table of contents ... |
Member of the Technical Staff at Hewlett-Packard Laboratories, Palo Alto, CA, 10/88-3/00:
Conducted research on servo systems for magnetic and optical disk drives. My most recent work had been research on rewritable DVD drives. This included work on high frequency wobbles (original idea and co-inventor), a new write clock generation scheme that allows near drop-in compatibility of rewritable media in DVD-ROM readers. This patented (US Patent # 6046968) scheme is the fundamental difference between the DVD+RW format and all other rewritable DVD schemes. I architected and co-developed real time testbed and separately wrote a large set of software that took measurements to web pages in a few keystrokes. Furthermore, I did some work in the end product applications for rewritable DVD systems, most notably real time video recording.
Prior to that, my work had been in the area of position sensing on disk drives. The general focus of this work was to identify the root causes of position sensing noise. This work generated a new servo demodulation algorithm (US Patent # 5801895). That work was inspired by a project on identifying the limiting factors for achieving high track density disk drives. I co-developed a straightforward methodology for isolating the major contributors to disk drive Position Error Signal and extrapolating this to future drives (US Patent # 5909661). Since HP's exit from the disk drive business and the publication of the method in 1997, this technique has become pervasive in the disk drive industry. I also organized department's internal web page to document measurements, data, and methodology from this project, thus making it all readily available to our customer division.
An earlier project dealt with high track density issues for a small form factor disk drive (the HP KittyHawk 1.3'' drive). At this time, I mentored a Ph.D. candidate from the Information Systems Laboratory at Stanford. We developed a tool for doing frequency domain evaluation of nonlinear systems. We used this tool to create an advanced model of friction in the actuator pivot bearing. I mentored the candidate as she followed this work with time domain modeling and compensation and provided guidance through her thesis defense.
I also did work on rejecting the effects of external shock and vibration on disk drives using auxiliary sensors (US Patent # 5663847). During this time, I evaluated the applicability of fuzzy logic control to compensate for the nonlinear behavior of disk drive actuator pivot. Upon gaining an understanding of the issues, I wrote what has become a well-known paper on understanding how, why, and when fuzzy logic controllers work.
My early research on optical drives focused on using multivariable identification and control to deal with crosstalk issues between the focus and tracking loops. This work led to one patent (US Patent # 5446648) and some new concepts in instrumentation. For this project, I also developed a DSP based control design/implementation tool that interfaced cleanly with Matlab. Sure, you say, can't anyone drop filters from Matlab into a running high speed MIMO control loop sampled at 20 kHz? Maybe that happens all the time now, but this was in 1990, and it was a lot harder to do back then.
| Top of this item | Back to the table of contents ... |
Sr. Research and Development Engineer for Ford Aerospace Corporation, Palo Alto, CA, 12/87-10/88: My work focused on signal processing applications, including: Lyapunov analysis of phase-lock loops, the control of distributed sensor network, and dynamic resource allocation for a signal processing application.
Research Assistant for Prof. Gene Franklin, Stanford University, 1/85-12/87: I worked on adaptive control of nonlinear systems. My original work dealt with adaptive control of linear systems with saturating inputs. Later, my work focused on identification and control of an unstable, nonlinear system.
Computer Software Engineer for Digital Equipment Corporation, Nashua, NH, 5/83-8/83: I did performance evaluation of backup facilities of VMS operating system.
Computer Software Engineer for Milliken & Co., Spartanburg, SC, 5/80-9/82: Spartanburg, SC, as part of co-op program at Clemson University. Over the course of four co-op assignments, I worked on a variety of computer control and performance monitoring systems for large textile ranges, texturing machines, and spinning and dyeing machines. I also worked on feasibility study for the company's future computer network. After returning to school, I learned that the before and after diagrams I had drawn were the key documents for the advantages of improving the computer network communicating to upper management.
| Back to the table of contents ... |
Ph.D. in Electrical Engineering from Stanford University, 1988.
My thesis research was on adaptive control, specifically on adaptive control applied to nonlinear dynamic systems. I worked for Professor Gene Franklin.
M.S. in Electrical Engineering from Stanford University, 1984.
This was a one-year masters. My classes focused on robotics, systems theory, adaptive systems, and computer systems.
B.S. in Electrical Engineering from Clemson University, 1983.
I graduated at the top of my class with a 4.0 grade average. I received the Faculty Scholarship Award at graduation. My time at Clemson focused on engineering classes related to computers and systems. I graduated in 4 years despite completing 4 sessions of a co-op assignment at Milliken and Company. I also did enough course work to minor in Spanish, although Electrical Engineering did not allow for a minor.
| Back to the table of contents ... |
| Back to the main page ... | Back to the table of contents ... |