Dr Arnfinn Aas Eielsen

Dr Arnfinn Aas Eielsen

Research Associate

School of Engineering (Electrical and Computer Engineering)

Career Summary

Biography

Arnfinn A Eielsen received the Siv.Ing. (MSc) degree and the Ph.D. degree in Engineering Cybernetics from the Norwegian University of Science and Technology, Trondheim, Norway in 2007 and 2012, respectively. He is currently employed as a research fellow in the School of Electrical Engineering and Computer Science at the University of Newcastle, Australia. Research interest include mathematical modeling, identification, adaptive systems, motion control, and control theory in general. He has extensive experience with experimental and prototype systems.


Qualifications

  • PhD, Norwegian University of Science and Technology

Keywords

  • Control Engineering
  • Signal Processing

Languages

  • Norwegian (Mother)
  • English (Fluent)

Fields of Research

Code Description Percentage
090609 Signal Processing 40
090602 Control Systems, Robotics and Automation 60

Professional Experience

UON Appointment

Title Organisation / Department
Research Associate University of Newcastle
School of Engineering
Australia

Teaching

Code Course Role Duration
TTK4125 Computerized Control in Industrial Systems
Norwegian University of Science and Technology (NTNU)
System analysis and design using UML, with emphasis on event and time driven systems. Use case, class, state, communication and sequence diagrams.
The C programming language: Pointers and complex data structures (arrays and structs). Operations on register level, bits in input and output registers, program development based on C.
Measurement principles: level, temperature, density, viscosity, moisture, force, torque and pressure.
Signal transmission, instrumentation amplifiers, power supply units, the power supply network, motors and motor control. Noise and noise subjugation, EMC.
Teaching assistant 1/01/2009 - 30/06/2009
TTK4115 Linear System Theory
Norwegian University of Science and Technology (NTNU)
Theory for linear multivariable systems, state space models, discretization, canonical forms and realizations, Lyapunov stability, controllability and observability, state feedback, LQ control, state estimation, the Kalman filter, descriptions of stochastic processes and random signals.
Teaching assistant 1/08/2008 - 31/12/2008
TTK4150 Nonlinear Control Systems
Norwegian University of Science and Technology (NTNU)
Methods for analysis and design of nonlinear systems, with an emphasis on nonlinear control systems. The course includes:
1) Mathematical models of nonlinear systems, and fundamental differences between the behavior of linear and nonlinear systems. Equilibrium points, limit cycles and general invariant sets.
2) Phase plane analysis, Lyapunov stability, Input-to-state stability, Input-Output stability, and Passivity analysis.
3) Nonlinear control design, including Lyapunov-based control, Energy-based control, Cascaded control, Passivity-based control, Input-Output linearization, and Backstepping.
Teaching assistant and lecturer 1/08/2010 - 31/12/2010
TTK4125 Computerized Control in Industrial Systems
Norwegian University of Science and Technology (NTNU)
System analysis and design using UML, with emphasis on event and time driven systems. Use case, class, state, communication and sequence diagrams.
The C programming language: Pointers and complex data structures (arrays and structs). Operations on register level, bits in input and output registers, program development based on C.
Measurement principles: level, temperature, density, viscosity, moisture, force, torque and pressure.
Signal transmission, instrumentation amplifiers, power supply units, the power supply network, motors and motor control. Noise and noise subjugation, EMC.
Teaching assistant 1/01/2008 - 30/06/2008
TTK4195 Modeling and Control of Robots
Norwegian University of Science and Technology (NTNU)
An overview over different types of manipulators.
Kinematics: description of position and orientation of rigid bodies, the Denavit-Hartenberg convention, forward and inverse kinematics, the velocity transformations, singularities, kinematics for vehicles.
Dynamics: dynamics of rigid bodies, reference frames in relative motion, equations of motion for manipulators and vehicles in closed and recursive form, elasticity.
Motion Planning: point-to-point motions, interpolation and path primitives, localization of robots, mapping a robot environment.
Control: feedback linearization, passivity based controllers, position and force control.
Teaching assistant 1/01/2008 - 30/06/2008
TTK4150 Nonlinear Control Systems
Norwegian University of Science and Technology (NTNU)
Methods for analysis and design of nonlinear systems, with an emphasis on nonlinear control systems. The course includes:
1) Mathematical models of nonlinear systems, and fundamental differences between the behavior of linear and nonlinear systems. Equilibrium points, limit cycles and general invariant sets.
2) Phase plane analysis, Lyapunov stability, Input-to-state stability, Input-Output stability, and Passivity analysis.
3) Nonlinear control design, including Lyapunov-based control, Energy-based control, Cascaded control, Passivity-based control, Input-Output linearization, and Backstepping.
Teaching assistant and lecturer 1/08/2009 - 31/12/2009
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Publications

For publications that are currently unpublished or in-press, details are shown in italics.


Journal article (10 outputs)

Year Citation Altmetrics Link
2017 Eielsen AA, Fleming AJ, 'Improving Digital-to-Analog Converter Linearity by Large High-Frequency Dithering', IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS, 64 1409-1420 (2017) [C1]
DOI 10.1109/TCSI.2016.2561778
Citations Scopus - 1Web of Science - 1
Co-authors Andrew Fleming
2017 Eielsen AA, Fleming AJ, 'Existing methods for improving the accuracy of digital-to-analog converters', REVIEW OF SCIENTIFIC INSTRUMENTS, 88 (2017) [C1]
DOI 10.1063/1.5000974
Co-authors Andrew Fleming
2016 Eielsen AA, Teo YR, Fleming AJ, 'Improving Robustness Filter Bandwidth in Repetitive Control by Considering Model Mismatch', Asian Journal of Control, (2016)

© 2016 Chinese Automatic Control Society and John Wiley & Sons Australia, Ltd. Repetitive control (RC) is used to track and reject periodic signals by including a model of ... [more]

© 2016 Chinese Automatic Control Society and John Wiley & Sons Australia, Ltd. Repetitive control (RC) is used to track and reject periodic signals by including a model of a periodic signal in the feedback path. The performance of RC can be improved by including an inverse plant response filter, but due to modeling uncertainty at high frequencies, a low-pass robustness filter is also required to limit the bandwidth of the signal model and ensure stability. The design of robustness filters is presently ad-hoc, which may result in excessively conservative performance. This article proposes a new automatic method for designing the robustness filter based on convex optimization and an uncertainty model. Experimental results on a nanopositioning system demonstrate that the proposed method outperforms the traditional brick-wall filter approach.

DOI 10.1002/asjc.1437
Co-authors Andrew Fleming
2016 Teo YR, Fleming AJ, Eielsen AA, Tommy Gravdahl J, 'A Simplified Method for Discrete-Time Repetitive Control Using Model-Less Finite Impulse Response Filter Inversion', Journal of Dynamic Systems, Measurement and Control, Transactions of the ASME, 138 (2016) [C1]

© 2016 by ASME. Repetitive control (RC) achieves tracking and rejection of periodic exogenous signals by incorporating a model of a periodic signal in the feedback path. To impro... [more]

© 2016 by ASME. Repetitive control (RC) achieves tracking and rejection of periodic exogenous signals by incorporating a model of a periodic signal in the feedback path. To improve the performance, an inverse plant response filter (IPRF) is used. To improve robustness, the periodic signal model is bandwidth-limited. This limitation is largely dependent on the accuracy of the IPRF. A new method is presented for synthesizing the IPRF for discrete-time RC. The method produces filters in a simpler and more consistent manner than existing best-practice methods available in the literature, as the only variable involved is the selection of a windowing function. It is also more efficient in terms of memory and computational complexity than existing methods. Experimental results for a nanopositioning stage show that the proposed method yields the same or better tracking performance compared to existing methods.

DOI 10.1115/1.4033274
Citations Scopus - 1
Co-authors Andrew Fleming
2015 Eielsen AA, Gravdahl JT, Leang KK, 'Low-order continuous-time robust repetitive control: Application in nanopositioning', Mechatronics, 30 231-243 (2015)

© 2015 Elsevier Ltd. All rights reserved. A low-order repetitive control (RC) design in continuous-time for nanopositioning applications is presented. It focuses on achieving hig... [more]

© 2015 Elsevier Ltd. All rights reserved. A low-order repetitive control (RC) design in continuous-time for nanopositioning applications is presented. It focuses on achieving high performance and sufficient robustness to uncertainties. The design is mainly applicable to analog implementation, but due to the exceptionally low order, it also results in a fast and efficient digital implementation. Experimental results for an analog implementation using a bucket brigade device (BBD), as well as a digital implementation, is presented. RC can provide fast and accurate tracking of periodic reference signals, which is useful in many scanning probe microscopy and nanofabrication applications.

DOI 10.1016/j.mechatronics.2015.07.006
Citations Scopus - 5
2015 Stakvik JÅ, Ragazzon MRP, Eielsen AA, Gravdahl JT, 'On Implementation of the Preisach Model: Identification and Inversion for Hysteresis Compensation', Modeling, Identification and Control: A Norwegian Research Bulletin, 36 133-142 (2015)
DOI 10.4173/mic.2015.3.1
Citations Scopus - 3
2014 Eielsen AA, Gravdahl JT, Leang KK, 'Low-order continuous-time robust repetitive control: Application in nanopositioning', Mechatronics, (2014)

A low-order repetitive control (RC) design in continuous-time for nanopositioning applications is presented. It focuses on achieving high performance and sufficient robustness to ... [more]

A low-order repetitive control (RC) design in continuous-time for nanopositioning applications is presented. It focuses on achieving high performance and sufficient robustness to uncertainties. The design is mainly applicable to analog implementation, but due to the exceptionally low order, it also results in a fast and efficient digital implementation. Experimental results for an analog implementation using a bucket brigade device (BBD), as well as a digital implementation, is presented. RC can provide fast and accurate tracking of periodic reference signals, which is useful in many scanning probe microscopy and nanofabrication applications.

DOI 10.1016/j.mechatronics.2015.07.006
2014 Eielsen AA, Vagia M, Gravdahl JT, Pettersen KY, 'Damping and tracking control schemes for nanopositioning', IEEE/ASME Transactions on Mechatronics, 19 432-444 (2014)

Fast and accurate tracking of reference trajectories is highly desirable in many nanopositioning applications, including scanning probe microscopy. Performance in common positioni... [more]

Fast and accurate tracking of reference trajectories is highly desirable in many nanopositioning applications, including scanning probe microscopy. Performance in common positioning stage designs is limited by the presence of lightly damped resonances and actuator nonlinearities such as hysteresis and creep. To improve the tracking performance in such systems, several damping and tracking control schemes have been presented in the literature. In this paper, six different control schemes are presented and applied to a nanopositioning system for experimental comparison. They include schemes applying damping control in the form of positive position feedback, integral resonant control, integral force feedback, and passive shunt-damping. Also, general pole placement in the form of model reference control, as well as a control scheme requiring only a combination of a low-pass filter and an integrator, is presented. The control schemes are fixed-structure, low-order control laws, for which few results exist in the literature with regard to optimal tuning. A practical tuning procedure for obtaining good tracking performance for five of the control schemes is, therefore, presented. Experimental results show that the schemes provide similar performance, and the main differences are due to the specific implementation of each scheme. © 2013 IEEE.

DOI 10.1109/TMECH.2013.2242482
Citations Scopus - 31
2013 Poloni T, Eielsen AA, Rohal'-Ilkiv B, Johansen TA, '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, 135 (2013)

Fast, reliable online estimation and model adaptation is the first step towards highperformance model-based nanopositioning control and monitoring systems. This paper considers th... [more]

Fast, reliable online estimation and model adaptation is the first step towards highperformance model-based nanopositioning control and monitoring systems. This paper considers the identification of parameters and the estimation of states of a nanopositioner with a variable payload based on the novel moving horizon optimized extended Kalman filter (MHEKF). The MHEKF is experimentally tested and verified with measured data from the capacitive displacement sensor. The payload, attached to the nanopositioner's sample platform, suddenly changes during the experiment triggering the transient motion of the vibration signal. The transient is observed through the load dependent parameters of a single-degree-of-freedom vibration model, such as spring, damping, and actuator gain constants. The platform, before and after the payload change, is driven by the excitation signal applied to the piezoelectric actuator. The information regarding displacement and velocity, together with the system parameters and a modeled force disturbance, is estimated through the algorithm involving the iterative sequential quadratic programming (SQP) optimization procedure defined on a moving horizon window. The MHEKF provided superior performance in comparison with the benchmark method, extended Kalman filter (EKF), in terms of faster convergence. © VC 2013 by ASME.

DOI 10.1115/1.4024008
Citations Scopus - 4
2012 Eielsen AA, Gravdahl JT, Pettersen KY, 'Adaptive feed-forward hysteresis compensation for piezoelectric actuators', Review of Scientific Instruments, 83 (2012)

Piezoelectric actuators are often employed for high-resolution positioning tasks. Hysteresis and creep nonlinearities inherent in such actuators deteriorate positioning accuracy. ... [more]

Piezoelectric actuators are often employed for high-resolution positioning tasks. Hysteresis and creep nonlinearities inherent in such actuators deteriorate positioning accuracy. An online adaptive nonlinear hysteresis compensation scheme for the case of symmetric hysteretic responses and certain periodic reference trajectories is presented. The method has low complexity and is well suited for real-time implementation. Experimental results are presented in order to verify the method, and it is seen that the error due to hysteresis is reduced by more than 90 compared to when assuming a linear response. © 2012 American Institute of Physics.

DOI 10.1063/1.4739923
Citations Scopus - 22
Show 7 more journal articles

Conference (19 outputs)

Year Citation Altmetrics Link
2016 Vagia M, Eielsen AA, Gravdahl JT, Pettersen KY, 'Nonlinear tracking control scheme for a nanopositioner', 24th Mediterranean Conference on Control and Automation, MED 2016, Athens, Greece (2016) [E1]
DOI 10.1109/MED.2016.7536016
2016 Eielsen AA, Fleming AJ, 'Improving DAC resolution in closed-loop control of precision mechatronic systems using dithering', 2016 IEEE 55th Conference on Decision and Control, CDC 2016, Las Vegas, Nevada (2016) [E1]
DOI 10.1109/CDC.2016.7798374
Co-authors Andrew Fleming
2016 Eielsen AA, Fleming AJ, 'Experimental assessment of dynamic digital-to-analog converter performance for applications in precision mechatronic systems', 2016 Australian Control Conference, AuCC 2016, Newcastle, NSW (2016) [E1]
DOI 10.1109/AUCC.2016.7868211
Co-authors Andrew Fleming
2015 Teo YR, Eielsen AA, Fleming AJ, 'Model-less FIR repetitive control with consideration of uncertainty', 2015 IEEE Conference on Control and Applications, CCA 2015 - Proceedings (2015) [E1]

© 2015 IEEE. Repetitive control (RC) is used to track and reject periodic exogenous signals by including a model of a periodic signal in the feedback path. The performance of RC ... [more]

© 2015 IEEE. Repetitive control (RC) is used to track and reject periodic exogenous signals by including a model of a periodic signal in the feedback path. The performance of RC can be improved by also including an. The accuracy of this filter is the main limitation to the RC bandwidth. The bandwidth is typically limited with a robustness filter - often a low-pass filter which attenuates the model at high-frequencies where the model-mismatch often occurs. In this paper, two robustness filter designs are compared. The first design is a brick-wall low-pass filter commonly used in the literature. The second design is based on the uncertainty between the inverse plant response filter and the measured response of the system. Experimental results demonstrate that the proposed method outperforms the traditional brick-wall filter approach.

DOI 10.1109/CCA.2015.7320670
Co-authors Andrew Fleming
2015 Ragazzon MRP, Gravdahl JT, Pettersen KY, Eielsen AA, 'Topography and force imaging in atomic force microscopy by state and parameter estimation', Proceedings of the American Control Conference (2015)

© 2015 American Automatic Control Council. A novel imaging method for atomic force microscopy based on estimation of state and parameters is presented. The cantilever dynamics is... [more]

© 2015 American Automatic Control Council. A novel imaging method for atomic force microscopy based on estimation of state and parameters is presented. The cantilever dynamics is modeled as a linear system augmented by the tip-sample interaction force. The states of this augmented system are observed. The tip-sample force function is based on the Lennard-Jones potential with a nonlinearly parameterized unknown topography parameter. By estimating this parameter together with the tip-sample force using a nonlinear observer approach, the topography of the sample can be found. The observer and parameter estimator is shown to be exponentially stable. Simulation results are presented and compared to a more conventional extended Kalman filter.

DOI 10.1109/ACC.2015.7171872
Citations Scopus - 2
2015 Godfrey TD, Eielsen AA, Fleming AJ, IEEE, 'Digital-to-analog Converter Considerations for Achieving a Dynamic Range of 1 ppm in Precision Mechatronics Systems', 2015 IEEE CONFERENCE ON CONTROL AND APPLICATIONS (CCA 2015) (2015) [E1]
Co-authors Andrew Fleming
2015 Gale S, Eielsen AA, Gravdahl JT, 'Modelling and simulation of a flywheel based energy storage system for an industrial manipulator', Proceedings of the IEEE International Conference on Industrial Technology (2015)

© 2015 IEEE. This paper investigates feasibility of using a flywheel based energy recovery and storage system for a robotic manipulator. The incentive is supported by ever growin... [more]

© 2015 IEEE. This paper investigates feasibility of using a flywheel based energy recovery and storage system for a robotic manipulator. The incentive is supported by ever growing necessity for efficient systems and optimisation of power consumption of industrial processes. Previous work has shown that robotic manipulators can benefit from incorporation of energy recovery and temporary energy storage system which resulted in significant reduction in power consumption. The ABB IRB 140 manipulator is used as a test bed for simulation and data collection. The manipulator internal parameters are identified and model is constructed using MATLAB/Simulink. The manipulator is programmed to executed a number of trajectories representing typical industrial tasks during which joints data is recorded and applied to the model. Simulation results show that flywheel based energy storage system is fully compatible with the manipulator controller hardware and is able to achieve reduction in power consumption.

DOI 10.1109/ICIT.2015.7125120
2014 Teo YR, Eielsen AA, Gravdahl TJ, Fleming AJ, 'Discrete-time repetitive control with model-less FIR filter inversion for high performance nanopositioning', 2014 IEEE/ASME International Conference on Advanced Intelligent Mechatronics AIM, Besancon, France (2014) [E1]
Citations Scopus - 5Web of Science - 3
Co-authors Andrew Fleming
2014 Eielsen AA, Gravdahl JT, Leang KK, 'Analog robust repetitive control for nanopositioning using bucket brigade devices', IFAC Proceedings Volumes (IFAC-PapersOnline) (2014)

© IFAC. In many applications of nanopositioning, such as scanning probe microscopy, tracking fast periodic reference trajectories with high accuracy is highly desirable. Repetiti... [more]

© IFAC. In many applications of nanopositioning, such as scanning probe microscopy, tracking fast periodic reference trajectories with high accuracy is highly desirable. Repetitive control is a simple and effective control scheme to obtain good tracking of such reference trajectories. In order to implement repetitive control, a method for introducing time-delay is necessary. This can easily be implemented using a memory buffer with digital signal processing equipment. To achieve fast, high accuracy, and low noise performance, fast microcontrollers or field-programmable gate array hardware with fast highresolution analog-to-digital and digital-to-analog converters are needed. As an inexpensive alternative to digital signal processing, the use of an analog bucket brigade device to implement the time-delay is investigated in this paper. Bucket brigade devices use switching to carry the input voltage over an array of capacitors, achieving a specified time-delay. Low-noise bucket brigade devices can achieve a signal-to-noise ratio around 80 dB, comparable to the actual performance when using 16-bit analog-to-digital converters. In this paper, the proposed control scheme utilizes a modified integral control law in conjunction with the repetitive control law. The overall control scheme ensures robustness towards plant uncertainty. Experimental results demonstrate the effectiveness of the overall control scheme and the analog implementation.

Citations Scopus - 2
2014 Ragazzon MRP, Eielsen AA, Gravdahl JT, 'H<inf>8</inf> reduced order control for nanopositioning: Numerical implementability', IFAC Proceedings Volumes (IFAC-PapersOnline) (2014)

© IFAC. In this paper we discuss how model reduction affects the stability and computational complexity of controllers for nanopositioning systems. A robust H &lt; inf &gt; 8 &lt... [more]

© IFAC. In this paper we discuss how model reduction affects the stability and computational complexity of controllers for nanopositioning systems. A robust H < inf > 8 < /inf > multiple-input multiple-output controller is designed and implemented for the lateral stage of an atomic force microscope. A model-based controller can often be of high order and may be difficult to run in real-time on hardware with limited computational power. The resulting controller can be considered to be stiff, which is characterized by a large spread of eigenvalues. Continuous-time systems running in real-time are often solved using explicit Runge-Kutta (ERK) methods, which easily becomes unstable for stiff systems. We show how small the time-step for a given controller needs to be for a selection of ERK methods. We also consider how model reduction affects the computational complexity of the controller, and show how the reduction can alter the placement of the eigenvalues and thus the required step-size for implementability. We demonstrate that the original 18th-order H < inf > 8 < /inf > controller can be reduced to a 10th-order controller without any significant reduction in performance or stability, which results in a 46.7% reduction in execution time, partly because the order reduction enables the use of a simpler solver type.

Citations Scopus - 2
2013 Vagia M, Eielsen AA, Gravdahl JT, Pettersen KY, 'Design of a nonlinear damping control scheme for nanopositioning', 2013 IEEE/ASME International Conference on Advanced Intelligent Mechatronics: Mechatronics for Human Wellbeing, AIM 2013 (2013)

The application of a nonlinear control law for vibration damping on a typical nanopositioning system is investigated. The nonlinear control law is an augmentation of the linear in... [more]

The application of a nonlinear control law for vibration damping on a typical nanopositioning system is investigated. The nonlinear control law is an augmentation of the linear integral force feedback scheme, where the constant gain used in integral force feedback, is replaced by a passive nonlinear operator. The nonlinear control law improves the performance of integral force feedback as it provides more rapid suppression of large disturbances, while maintaining low noise sensitivity. L 2 -stability for the control law is established. Experimental results are presented, showing improved performance when applying the nonlinear augmentation of the integral force feedback scheme, compared to the original linear integral force feedback scheme. © 2013 IEEE.

DOI 10.1109/AIM.2013.6584074
Citations Scopus - 2
2013 Eielsen AA, Vagia M, Gravdahl JT, Pettersen KY, 'Fixed-structure, low-order damping and tracking control schemes for nanopositioning', IFAC Proceedings Volumes (IFAC-PapersOnline) (2013)

Fast and accurate tracking of periodic reference trajectories is highly desirable in many nanopositioning applications, including scanning probe microscopy. Performance in common ... [more]

Fast and accurate tracking of periodic reference trajectories is highly desirable in many nanopositioning applications, including scanning probe microscopy. Performance in common positioning stage designs is limited by the presence of lightly damped resonances, and actuator nonlinearities such as hysteresis and creep. To improve the tracking performance in such systems, several damping and tracking control schemes have been presented in the literature. In this paper, five different control schemes are presented and applied to a nanopositioning system for experimental comparison. They include schemes applying damping control in the form of positive position feedback, integral resonant control, integral force feedback, and passive shunt-damping. Also, a control scheme requiring only a combination of a low-pass filter and an integrator is presented. The control schemes are fixed-structure, low-order control laws, for which few results exist in the literature with regards to optimal tuning. A practical tuning procedure for obtaining good tracking performance for all of the presented control schemes is therefore presented. The schemes provide similar performance, and the main differences are due to the specific implementation of each scheme. © 2013 IFAC.

DOI 10.3182/20130410-3-CN-2034.00026
2012 Poloni T, Eielsen AA, Rohal'-Ilkiv B, Johansen TA, 'Moving Horizon Observer for vibration dynamics with plant uncertainties in nanopositioning system estimation', Proceedings of the American Control Conference (2012)

This paper considers the estimation of states and parameters of a Single-Degree-of-Freedom (SDOF) vibration model in nanopositioning system based on a nonlinear Moving Horizon Obs... [more]

This paper considers the estimation of states and parameters of a Single-Degree-of-Freedom (SDOF) vibration model in nanopositioning system based on a nonlinear Moving Horizon Observer (MHO). The MHO is experimentally tested and verified on measured data. The information about the displacement and speed together with the system parameters and unmodeled force disturbance is estimated through the Sequential Quadratic Programming (SQP) optimization procedure. The MHO provided superior performance in comparison with the benchmark method Extended Kalman Filter (EKF) in terms of faster convergence. © 2012 AACC American Automatic Control Council).

Citations Scopus - 6
2012 Eielsen AA, Gravdahl JT, Leang KK, 'Robust damping PI repetitive control for nanopositioning', Proceedings of the American Control Conference (2012)

In many applications of nanopositioning, such as scanning probe microscopy, tracking fast periodic reference trajectories with high accuracy is highly desirable. Repetitive contro... [more]

In many applications of nanopositioning, such as scanning probe microscopy, tracking fast periodic reference trajectories with high accuracy is highly desirable. Repetitive control (RC) is a simple and effective scheme to obtain good tracking of such reference trajectories. However, the highly resonant dynamics of the positioning stage combined with hysteresis and creep behavior in the piezoelectric actuator can degrade performance and even make creating a stable RC system difficult. In this paper, a damping proportionalintegral (PI) controller is combined with a repetitive controller for robustness and high performance. Compared to a regular PI controller, the modified PI controller introduces damping, increases the bandwidth, and reduces the overall noise level due to feedback. Also, due to the integral action, the hysteresis and creep nonlinearities inherent in the piezoelectric actuator is minimized. A novel method for tuning the PI controller is proposed. The control approach is applied to a custom-design flexure-guided nanopositioning system with a dominant resonance of approximately 725 Hz. Experimental results demonstrate the effectiveness of the overall control scheme, and the maximum tracking error for scanning at 100 Hz and 400 Hz is measured at 0.27% and 2.7%, respectively, of the total positioning range. © 2012 AACC American Automatic Control Council).

Citations Scopus - 6
2012 Eielsen AA, Gravdahl JT, 'Adaptive control of a nanopositioning device', Proceedings of the IEEE Conference on Decision and Control (2012)

High-bandwidth tracking control is desirable in many nanopositioning applications, including scanning probe microscopy. Typical nanopositioner designs have several sources of unce... [more]

High-bandwidth tracking control is desirable in many nanopositioning applications, including scanning probe microscopy. Typical nanopositioner designs have several sources of uncertainty which can degrade control performance, and even induce instability. Salient uncertainties are in the control gain and the resonant frequencies of the mechanical structure. The control gain varies due to hysteresis and creep which result in a control gain that is dependent on the offset, range, and form of the driving signal, as well as actuator temperature and age. The resonant frequencies change due to payload mass. In order to maintain performance in the presence of a moderately changing dynamic response, a model reference adaptive control (MRAC) scheme is proposed and implemented. The details of implementing a working MRAC will be discussed. Most notably, a novel augmentation of the parameter identification scheme in the form of a special pre-filter will be shown to be necessary to obtain parameter convergence, and thus also for stability and performance in the case of the MRAC scheme. Experimental results are presented to assess the performance. © 2012 IEEE.

DOI 10.1109/CDC.2012.6426799
Citations Scopus - 2
2011 Eielsen AA, Polóni T, Johansen TA, Gravdahl JT, 'Experimental comparison of online parameter identification schemes for a nanopositioning stage with variable mass', IEEE/ASME International Conference on Advanced Intelligent Mechatronics, AIM (2011)

An experimental comparison of two common parameter identification schemes is presented. The recursive least-squares method and the extended Kalman filter are applied to identify t... [more]

An experimental comparison of two common parameter identification schemes is presented. The recursive least-squares method and the extended Kalman filter are applied to identify three parameters of a second-order linear mass-spring-damper model, using data obtained from a nanopositioning stage with a highly resonant dynamic response. © 2011 IEEE.

DOI 10.1109/AIM.2011.6027083
Citations Scopus - 4
2011 Eielsen AA, Burger M, Gravdahl JT, Pettersen KY, 'PI 2-controller applied to a piezoelectric nanopositioner using conditional integrators and optimal tuning', IFAC Proceedings Volumes (IFAC-PapersOnline) (2011)

For tracking control of nanopositioning stages using piezoelectric actuators, controllers with integral action can be employed to robustly track a reference in the presence of hys... [more]

For tracking control of nanopositioning stages using piezoelectric actuators, controllers with integral action can be employed to robustly track a reference in the presence of hysteresis, creep, and plant parametric uncertainties. In any practical configuration of instrumentation for this application, saturations will be present. Thus, a controller with integral action is prone to windup, which typically cause large transients and long settling times, and will in general degrade performance and potentially damage equipment. In this paper it is demonstrated that conditional integrators provides a very accessible and convenient framework for introducing anti-windup for any order integral controller, and the effectiveness is verified experimentally. Also, the inuence reconstruction and anti-aliasing filters have on the stability limits for PI and PI 2 controllers is investigated, and a novel tuning procedure is proposed in order to obtain the best performance for the overall system. It is demonstrated experimentally that optimal tuning can damp resonances and increase bandwidth. © 2011 IFAC.

DOI 10.3182/20110828-6-IT-1002.01401
Citations Scopus - 8
2010 Eielsen AA, Fleming AJ, 'Passive shunt damping of a piezoelectric stack nanopositioner', 2010 American Control Conference, ACC 2010, Baltimore, MD (2010) [E1]
Citations Scopus - 16Web of Science - 12
Co-authors Andrew Fleming
2010 Eielsen AA, Gravdahl JT, Pettersen KY, Vogl L, 'Tracking control for a piezoelectric nanopositioner using estimated states and feedforward compensation of hysteresis', IFAC Proceedings Volumes (IFAC-PapersOnline) (2010)

Nanopositioning stages utilizing piezoelectric actuators exhibit several undesired features inhibiting good reference tracking performance. The most salient features are lightly d... [more]

Nanopositioning stages utilizing piezoelectric actuators exhibit several undesired features inhibiting good reference tracking performance. The most salient features are lightly damped mechanical resonances, hysteresis, and creep. In addition, sensor noise can limit the resolution achievable when applying closed-loop control schemes. In order to reduce sensor noise when using closed-loop control, we develop a state estimator in the form of an adaptive Luenberger observer. Furthermore, we propose a novel method for compensating the hysteretic behavior in piezoelectric actuators when tracking a reference trajectory, and present a method for online identification of the parameters of the system, aiming for simplicity and ease of implementation. The backstepping framework is used to obtain an adaptive control law and to analyze stability and boundedness of the tracking error. Experimental results are presented in order to assess the performance of the proposed hysteresis compensation, as well as the backstepping control law, on a flexure-based nanopositioner using piezoelectric actuators. © 2010 IFAC.

DOI 10.3182/20100913-3-US-2015.00106
Citations Scopus - 1
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Grants and Funding

Summary

Number of grants 2
Total funding $11,140

Click on a grant title below to expand the full details for that specific grant.


20151 grants / $1,200

2015 IEEE Multi-Conference on Systems and Control, Novotel Manly Pacific, Sydney, 21 - 23 September 2015$1,200

Funding body: University of Newcastle - Faculty of Engineering & Built Environment

Funding body University of Newcastle - Faculty of Engineering & Built Environment
Project Team Doctor Arnfinn Aas Eielsen
Scheme Travel Grant
Role Lead
Funding Start 2015
Funding Finish 2015
GNo G1501093
Type Of Funding Internal
Category INTE
UON Y

20141 grants / $9,940

2014 International Visitor from Norwegian University of Science and Technology, Norway$9,940

Funding body: University of Newcastle

Funding body University of Newcastle
Project Team Doctor Andrew Fleming, Doctor Arnfinn Aas Eielsen
Scheme International Research Visiting Fellowship
Role Investigator
Funding Start 2014
Funding Finish 2014
GNo G1400875
Type Of Funding Internal
Category INTE
UON Y
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Research Supervision

Number of supervisions

Completed1
Current1

Total current UON EFTSL

PhD0.1

Current Supervision

Commenced Level of Study Research Title Program Supervisor Type
2016 PhD Control and Optimisation for Nanolithography PhD (Electrical Engineering), Faculty of Engineering and Built Environment, The University of Newcastle Co-Supervisor

Past Supervision

Year Level of Study Research Title Program Supervisor Type
2017 PhD Damping and Tracking Controllers for Nanopositioning Systems: Applications for High-Speed Scanning Probe Microscopy PhD (Electrical Engineering), Faculty of Engineering and Built Environment, The University of Newcastle Co-Supervisor
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Dr Arnfinn Aas Eielsen

Position

Research Associate
School of Engineering
Faculty of Engineering and Built Environment

Focus area

Electrical and Computer Engineering

Contact Details

Email arnfinnaas.eielsen@newcastle.edu.au
Mobile 0475 909 828
Link Research Networks

Office

Building EF - Engineering Classrooms
Location Callaghan
University Drive
Callaghan, NSW 2308
Australia
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