Guest lecture by Associate Professor Arnfinn Aas Eielsen, University of Stavanger, Norway


16.05.2018 kl. 10.00 - 16.05.2018 kl. 11.00


“Dithering and Analogue-to-Digital Conversion in Control Applications”


Digital-to-analogue converters (DACs) is presently the principal limitation to improved accuracy in precision mechatronic systems.

Other high-quality components, sensors and actuators used in the signal-chain have lower impact on the overall non-linearity and noise contribution.

Examples of precision mechatronic system include adaptive optics, semiconductor lithography, semiconductor fabrication and inspection, laser interferometry, metrology (measurement science), imaging and manipulation in microbiology, chemistry, materials science, and scanning probe microscopy in general.

A DAC will have several non-ideal effects that generate distortion, and these effects will in general be the main contributors of disturbances. Noise is presently less of a problem. Hence, we have investigated several, if not all, known techniques for mitigating static and dynamic non-linearities in DACs, and came to the conclusion that large-scale dithering is most effective in terms of reducing the impact of static and some dynamic non-linear effects.

Arnfinn A. Eielsen received the Siv.Ing. (MSc) degree and the in Engineering Cybernetics from the Norwegian University of Science and Technology, Trondheim, Norway, in 2007 and 2012, respectively. He is currently employed as an associate professor at the University of Stavanger, and has previously been employed as a research Associate in the School of Electrical Engineering and Computer Science at the University of Newcastle, Australia. He has mainly worked on precision mechatronics systems, particularly with adaptive non-linear observers for hysteresis, fixed structure and order control law synthesis, repetitive control, and most recently control of and signal processing in digital-to-analogue converters and laser interferometric systems. General research interest include mathematical modeling, identification, adaptive systems, motion control, and control theory.

All are welcome.


Free of Charge


Automation and Control Section, Department of Electronic Systems


Aalborg University, Fredrik Bajers Vej 7, C3-204