Et profilbilde

Førsteamanuensis
Arnfinn Aas Eielsen { "honorific-suffix": "Førsteamanuensis", "fn": "Arnfinn Aas Eielsen", "tel": "Telefon: 51832823", "email": "arnfinn.a.eielsen@uis.no" }

Avdeling/enhet Det teknisk- naturvitenskapelige fakultet
Institutt/senter Institutt for data- og elektroteknologi
Rom KE E-438

Forskningsområder

Control theory: Repetitive control; fixed-order, fixed-structure control laws; adaptive control Instrumentation: Digital-to-analog converters for high-precision motion control, laser interferometric displacement measurements

Utvalgte publikasjoner

[1] AA Eielsen, JT Gravdahl, and KY Pettersen. Adaptive feed-forward hysteresis compensation for piezoelectric actuators. Review of Scientific Instruments, 2012.
[2] T Polóni, AA Eielsen, B Rohal?-Ilkiv, and TA Johansen. Adaptive Model Estimation of Vibration Motion for a Nanopositioner with Moving Horizon Optimized Extended Kalman Filter. Journal of Dynamic Systems Measurement and Control, Transactions of the ASME, 2013.
[3] AA Eielsen, M Vagia, JT Gravdahl, and KY Pettersen. Damping and Tracking Control Schemes for Nanopositioning. Mechatronics, IEEE/ASME Transactions on, 2014.
[4] AA Eielsen, JT Gravdahl, and KK Leang. Low-order continuous-time robust repetitive control: Application in nanopositioning. Mechatronics, 2015.
[5] JÅ Stakvik, MRP Ragazzon, AA Eielsen, and JT Gravdahl. On Implementation of the Preisach Model: Identification and Inversion for Hysteresis Compensation. Modeling, Identification and Control, 2015.
[6] YR Teo, AA Eielsen, JT Gravdahl, and AJ Fleming. A Simplified Method for Discrete-Time Repetitive Control Using Model-Less FIR Filter Inversion. Journal of Dynamic Systems Measurement and Control, Transactions of the ASME, 2016.
[7] AA Eielsen and AJ Fleming. Improving Digital-to-analog Converter Linearity by Large High-frequency Dithering. Circuits and Systems I, IEEE Transactions on, 2016.
[8] AA Eielsen, YR Teo, and AJ Fleming. Improving Robustness Filter Bandwidth in Repetitive Control by Considering Model Mismatch. Asian Journal of Control, 2016.
[9] AA Eielsen and AJ Fleming. Existing Methods for Improving the Accuracy of Digital-to-Analog Converters. Review of Scientific Instruments, 2017.

Pågående forskning

Developing a prototype ultra-high resolution digital-to-analog converter with 50 kHz bandwidth using methods from nonlinear control theory.

The current state-of-the-art for low-latency converters is approximately 15 effective number of bits (ENOB) and 16 ENOB for Delta-Sigma modulators (which has latencies in excess of 400 µs). Our current experimental setup yields in excess of 17 ENOB with only interface latency (less than 1 µs). The goal is to reach 21 ENOB (equivalent of a dynamic range of 1 ppm).

Simplified interferometer with sub-nanometer resolution and high bandwidth for displacement measurements.

Using a Fabry?Pérot scanning interferometer optical design, it is the goal of the project to use dithering techniques to obtain the same performance as more optically elaborate Fabry?Pérot and Michelson interferometers (that are using e.g. multiple wavelengths, multiple beams, and adaptive interpolation).

Arbeidserfaring

2018-current: University of Stavanger (Stavanger, Norway),
Associate professor: Cybernetics.
2017: University of Newcastle (Newcastle, Australia),
Research associate: Researching system identification (maximum likelihood, expectation maximization). Teaching. Co-supervisor for PhD students. Reviewer for international conferences and journals.
2015-2017: University of Newcastle (Newcastle, Australia),
Postdoctoral fellow: Researched high-resolution data-conversion, and interferometer-based distance measurement. Assembled lab facilities. Co-supervisor for PhD and Master?s students. Reviewer for international conferences and journals.
2013-2014: Norwegian University of Science and Technology (Trondheim, Norway),
Postdoctoral researcher: Researched periodic motion control and high-resolution data-conversion. Co-supervisor for PhD and Master?s students. Reviewer for international conferences and journals.
2008-2012: Norwegian University of Science and Technology (Trondheim),
PhD candidate: Researched motion control for precision systems, esp. scanning probe microscopy. Planned and assembled a lab for research on precision mechatronics. Co-supervisor for Master?s students.
2008-2010: Norwegian University of Science and Technology (Trondheim),
Teaching assistant: Developed software for student lab booking (PHP and SQL) and a fully automatic system for optical mark recognition on student feedback questionnaires. Teaching duties in: TTK4125 Computerized control in industrial systems, TTK4195 Modeling and control of robots, TTK4115 Linear systems theory, and TTK4150 Non-linear systems theory.
2007-2009: St. Olavs Hospital (Trondheim),
Software developer: Developed a system for handling medical questionnaires and demographic information, based on XML, Ruby on Rails, Java, and SQL.
2007: Norwegian University of Science and Technology/St. Olavs Hospital (Trondheim),
Research assistant: Instrumented a portable lab for video analysis of infants with cerebral palsy.
2006: NeoGuide Systems, Inc. (Los Gatos, California),
Intern via Gründerskolen: Worked on instrumentation, measurements, and automating test procedures for a medical robotics device.
2005: Sensorlink AS (Trondheim),
Embedded software developer: Developed software for reading and storing measurement data from a pipeline corrosion-monitoring device using the GNU C/C++ AVR toolchain on an Atmel AVR microcontroller.
2004: Statoil ASA (Trondheim),
Software developer: Summer project (competitive mentoring and technology development program). Developed software for retrieving and visualizing measurements of pipeline corrosion, based on Java, the Java 3D API, and an SQL database. In cooperation with Sensorlink AS.

Vitenskapelige publikasjoner (fra CRISTin)

  • Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy (veileder) (2012). Topics in Control of Nanopositioning Devices. Norges teknisk-naturvitenskapelige universitet. ISBN 978-82-471-3949-3. 209 s.
  • Vagia, Marialena; Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy; Pettersen, Kristin Ytterstad (2016). Nonlinear Tracking Control Scheme for a Nanopositioner. IEEE; 2016-06-21 - 2016-06-24.
  • Gale, Serge; Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy (2015). Modelling and Simulation of a Flywheel Based Energy Storage System for an Industrial Manipulator. IEEE; 2015-03-17 - 2015-03-19.
  • Ragazzon, Michael Remo Palmén; Gravdahl, Jan Tommy; Pettersen, Kristin Ytterstad; Eielsen, Arnfinn Aas (2015). Topography and Force Imaging in Atomic Force Microscopy by State and Parameter Estimation. 2015-07-01 - 2015-07-03.
  • Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy; Leang, Kam K. (2014). Analog Robust Repetitive Control for Nanopositioning Using Bucket Brigade Devices. IFAC; 2014-08-24 - 2014-08-29.
  • Ragazzon, Michael Remo Palmén; Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy (2014). H_inf Reduced Order Control for Nanopositioning: Numerical Implementability. IFAC; 2014-08-24.
  • Teo, Yik R.; Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy; Fleming, Andrew J. (2014). Discrete-Time Repetitive Control With Model-Less FIR Filter Inversion for High Performance Nanopositioning. IEEE; 2014-07-08 - 2014-07-11.
  • Eielsen, Arnfinn Aas; Vagia, Marialena; Gravdahl, Jan Tommy; Pettersen, Kristin Ytterstad (2013). Fixed-Structure, Low-Order Damping and Tracking Control Schemes for Nanopositioning. IFAC; 2013-04-10 - 2013-04-12.
  • Vagia, Marialena; Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy; Pettersen, Kristin Ytterstad (2013). Design of a nonlinear damping control scheme for nanopositioning. IEEE/ASME; 2013-07-09 - 2013-07-12.
  • Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy (2012). Adaptive Control of a Nanopositioning Device. IEEE; 2012-12-10 - 2012-12-13.
  • Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy; Leang, Kam K. (2012). Robust Damping PI Repetitive Control for Nanopositioning. American Automatic Control Council (AACC); 2012-06-27 - 2012-06-29.
  • poloni, tomas; Eielsen, Arnfinn Aas; Rohal-Ilkiv, B; Johansen, Tor Arne (2012). Moving Horizon Observer for Vibration Dynamics with Plant Uncertainties in Nanopositioning System Estimation. 2012-06-27 - 2012-06-29.
  • Eielsen, Arnfinn Aas; Burger, Mernout; Gravdahl, Jan Tommy; Pettersen, Kristin Ytterstad (2011). PI2-Controller Applied to a Piezoelectric Nanopositioner Using Conditional Integrators and Optimal Tuning. IFAC; 2011-08-28 - 2011-09-02.
  • Eielsen, Arnfinn Aas; poloni, tomas; Johansen, Tor Arne; Gravdahl, Jan Tommy (2011). Experimental Comparison of Online Parameter Identification Schemes for a Nanopositioning Stage with Variable Mass. IEEE; 2011-07-03 - 2011-07-07.
  • Eielsen, Arnfinn Aas; Fleming, Andrew J. (2010). Passive Shunt Damping of a Piezoelectric Stack Nanopositioner. IFAC; 2010-06-30 - 2010-07-02.
  • Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy; Pettersen, Kristin Ytterstad; Vogl, Lukas (2010). Tracking Control for a Piezoelectric Nanopositioner Using Estimated States and Feedforward Compensation of Hysteresis. IFAC; 2010-09-13 - 2010-09-15.