2 Guest Lectures by Professor David Q. Mayne, Imperial College London, on "MPC Stability and Robustness"

1st lecture: 13 October 2014 at 09:15-11:00 in H1, Gløshaugen campus
2nd lecture: 14 October 2014 at 14:15-16:00 in EL4, Gløshaugen campus

2 Guest Lectures by Professor David Q. Mayne, Imperial College London, on "MPC Stability and Robustness"

1st lecture: 13 October 2014 at 09:15-11:00 in H1, Gløshaugen campus
2nd lecture: 14 October 2014 at 14:15-16:00 in EL4, Gløshaugen campus

The lectures will be based on Chapter 2 and 3 in his book with Jim Rawlings, "Model Predictive Control: Theory and Design".

Professor Mayne is a legend in the automatic control community, see Wikipedia and IEEE Global History Network (from which the below is copied):

"David Quinn Mayne's wide collection of research contributions has had tremendous impact on the development of control theory. Among these, the most important is his work in optimizing model predictive control (MPC), in which he provided a rigorous mathematical basis for analyzing MPC algorithms. His framework for studying the stability of MPC loops has become highly influential in MPC, whose impact can be seen in today's high-speed electromechanical, aerospace and automotive systems.

Dr. Mayne was the first to describe what is now known as "particle filtering," which is one of the central building blocks in nonlinear filtering. These methods are used in a vast array of applications including vehicle autopilots, aircraft tracking and the prediction of commodity prices. He also introduced the concept of differential dynamic programming as a method for solving optimal control problems and provided early guidelines for adaptive control.

An IEEE Life Fellow, Dr. Mayne is currently an emeritus professor and senior research investigator at Imperial College London."
 

3 Days Seminar on Sensor Fusion: Professor Fredrik Gustafsson, Linköping University

20 October 2014 at 13:15-15:00  (Sensor Networks)
21 October 2014 at 13:15-16:00 (UKF with an EKF perspectiv and particle filters)
22 October 2014 at 16:15-18:00 (SLAM as an application of EKF and particle filters)
Room B-343, Elektro Bld. D, Gløshaugen

 

3 Days Seminar on Sensor Fusion: Professor Fredrik Gustafsson, Linköping University

20 October 2014 at 13:15-15:00  (Sensor Networks)
21 October 2014 at 13:15-16:00 (UKF with an EKF perspectiv and particle filters)
22 October 2014 at 16:15-18:00 (SLAM as an application of EKF and particle filters)
Room B-343, Elektro Bld. D, Gløshaugen

 

AMOS welcome Professor Frederik Gustafsson from Linköping University, Sweden. Professor Gustafsson is one of the authorites on sensor fusion and he will be giving a series on lectures in the period 20-22 October 2014.

About the Speaker: Fredrik Gustafsson is a professor in Sensor Informatics at Department of Electrical Engineering, Linköping University, since 2005. He received the M.Sc. degree in electrical engineering 1988 and the PhD degree in Automatic Control, 1992, both from Linköping University. During 1992-1999 he held various positions in automatic control, and 1999-2005 he was professor in Communication Systems.

Research interests: His research interests are in stochastic signal processing, adaptive filtering and change detection, with applications to communication, vehicular, airborne and audio systems.

Editorships: He was an associate editor for IEEE Transactions of Signal Processing 2000-2006 and Journal on Observations and Navigation 2008-2011. He is currently associate editor for EURASIP Journal on Applied Signal Processing and IEEE Transactions on Aerospace and Electronic Systems. He was head of the Signal and Systems review panel for the Swedish Research Council (VR) 2009, 2011 and 2012.

Fellowships: Distinguished Professor (rådsprofessor) awarded from the Swedish Research Council 2015-2024. IEEE Fellow (2011). Elected member of the Royal Academy of Engineering Sciences (IVA) 2007.

Awards: Arnberg prize 2004 from the Royal Swedish Academy of Science (KVA). SAAB award in the name of former CEO Åke Svensson 2011.
Harry Rowe Mimno Best Paper Award 2011 for the tutorial "Particle Filter Theory and Practice with Positioning Applications", which was published in the IEEE AESS Magazine in July 2010. Entrepreneurial researcher of the year at Linköping University, 2012.

 


3 Guest Lectures on Hydrodynamic Aspects of Marine Structures

9, 16 and 23 March 2015 at 13:15-16:00
Room T6, Marine Technology Centre, Tyholt

3 Guest Lectures on Hydrodynamic Aspects of Marine Structures

9, 16 and 23 March 2015 at 13:15-16:00
Room T6, Marine Technology Centre, Tyholt

1.
9 March 2015 at 13:15-16:00
Room T6, Marine Technology Centre, Tyholt
"Harmonic Polynomial Cell (HPC) methods and its applications in marine hydrodynamics"
Lecturer: Dr. Yanlin  Shao

2.
16 March 2015 at 13:15-16:00
Room T6, Marine Technology Centre, Tyholt
"Mesh generation and analysis for Computational Fluid Mechanics"
Lecturer: Dr. Giuseppina Colicchio

3.
23 March 2015 at 13:15-16:00
Room T6, Marine Technology Centre, Tyholt
"Wave impacts in sloshing flows"
Lecturer: Prof. Claudio Lugni


3rd PROST seminar in 2014: Prof. David Q. Mayne, Imperial College London, on tube-based control of constrained nonlinear systems

15 October 2014 at 12:30-13:30
Room K4-203, Chemistry builing 4, Gløshaugen campus

This seminar is in addition to the two lectures on MPC stability and robustness that David Q. Mayne gives 13 and 14 October 2014.

3rd PROST seminar in 2014: Prof. David Q. Mayne, Imperial College London, on tube-based control of constrained nonlinear systems

15 October 2014 at 12:30-13:30
Room K4-203, Chemistry builing 4, Gløshaugen campus

This seminar is in addition to the two lectures on MPC stability and robustness that David Q. Mayne gives 13 and 14 October 2014.

"David Quinn Mayne's wide collection of research contributions has had tremendous impact on the development of control theory. Among these, the most important is his work in optimizing model predictive control (MPC), in which he provided a rigorous mathematical basis for analyzing MPC algorithms. His framework for studying the stability of MPC loops has become highly influential in MPC, whose impact can be seen in today's high-speed electromechanical, aerospace and automotive systems.

Dr. Mayne was the first to describe what is now known as "particle filtering," which is one of the central building blocks in nonlinear filtering. These methods are used in a vast array of applications including vehicle autopilots, aircraft tracking and the prediction of commodity prices. He also introduced the concept of differential dynamic programming as a method for solving optimal control problems and provided early guidelines for adaptive control.

An IEEE Life Fellow, Dr. Mayne is currently an emeritus professor and senior research investigator at Imperial College London."

Guest lecture by Associate Professor Ulrik Dam Nielsen, Technical University of Denmark, on Response-based sea state estimation - Safe and efficient ship operations in a seaway

13 November 2014 at 12:15-13:00
Room T6, Marine Technology Centre

Guest lecture by Associate Professor Ulrik Dam Nielsen, Technical University of Denmark, on Response-based sea state estimation - Safe and efficient ship operations in a seaway

13 November 2014 at 12:15-13:00
Room T6, Marine Technology Centre

Abstract:
The presentation focuses mainly on work made in relation to the wave buoy analogy, where the central point is to use available wave-induced global vessel responses (motion components, accelerations, hull girder strains, etc.) to make on-site sea state estimation from an advancing ship in a seaway. Thus, within technical ship operations at sea – and more generally for all maritime operations – knowledge of the on-site sea state can be used to improve both safety and efficiency. In particular, this type of sea state estimation can provide fundamental information to control- and decision support systems (DSS), which also include the area of dynamic positioning, where the sea state estimate can be used for feed-forward control, improving both station-keeping behaviour and fuel consumption. Moreover, vessel performance systems for onboard as well onshore (‘in-house office') fleet analyses gain advantage by having available continuous estimates of the sea state at the particular position.

Short bio:
In 2005, Ulrik Dam Nielsen obtained his Ph.D. degree from the Section of Coastal, Maritime and Structural Engineering at DTU Mechanical Engineering. After four years as Post Doc. and assistant professor at DTU, Ulrik joined, in 2009, the staff of DTU Mechanical Engineering as an associate professor. He has since then been involved in research and teaching primarily about wave-ship interactions with a main focus on onboard monitoring and decision support systems for operational guidance and performance. In the research, several topics are addressed, including analysis of full-scale measurements, in-situ estimation of the sea state at the location of an advancing vessel, fatigue damage accumulation in the hull girder, numerical models for the prediction of ship responses. Ulrik has since January this year, 2014, been affiliated with AMOS as an associate professor II.

Guest Lecture by Associate Professor Ulrik Dam Nielsen, Technical University of Denmark, on safe and efficient ship operations in a seaway – response‐based sea state estimation used in onboard DSS

30 September 2014 at 12:00-12:45
Room AMOS 2, Marine Technology Centre, Tyholt

Guest Lecture by Associate Professor Ulrik Dam Nielsen, Technical University of Denmark, on safe and efficient ship operations in a seaway – response‐based sea state estimation used in onboard DSS

30 September 2014 at 12:00-12:45
Room AMOS 2, Marine Technology Centre, Tyholt

About the presentation

Safe and efficient ship operations in a seaway – Response‐based sea state estimation used in onboard DSS

by Assoc. prof. Ulrik Dam Nielsen

The presentation focuses mainly on work made in relation to the wave buoy analogy, where the central point is to use available wave‐induced global vessel responses (motion components, accelerations, hull girder strains, etc.) to make on‐site sea state estimation from an advancing ship in a seaway. Thus, within technical ship operations at sea – and more generally for all maritime operations – knowledge of the onsite sea state can be used to improve both safety and efficiency. In particular, this type of sea state estimation can provide fundamental information to control‐ and decision support systems (DSS), which also include the area of dynamic positioning, where the sea state estimate can be used for feed‐forward control, improving both station‐keeping behaviour and fuel consumption. Moreover, vessel performance systems for onboard as well onshore (‘in‐house office') fleet analyses gain advantage by having available continuous estimates of the sea state at the particular position.

Guest Lecture by Prof. A. Pedro Aguiar, University of Porto, on "Cooperative Navigation and Motion Control of Multiple Marine Autonomous Robotic Vehicles"

31 October 2014 at 11:15-12:00
Room B343, Electro building B, Gløshaugen campus (map)

Guest Lecture by Prof. A. Pedro Aguiar, University of Porto, on "Cooperative Navigation and Motion Control of Multiple Marine Autonomous Robotic Vehicles"

31 October 2014 at 11:15-12:00
Room B343, Electro building B, Gløshaugen campus (map)

ABSTRACT

This talk addresses the general topic of cooperative navigation and motion control of marine autonomous robotic vehicles, both from a theoretical and a practical standpoint. The presentation is rooted in practical developments and experiments. Examples of scientific mission scenarios with autonomous surface vehicles (ASVs) and autonomous underwater vehicles (AUVs), acting alone or in cooperation, set the stage for the main contents of the presentation. From a theoretical standpoint, special attention is given to a number of challenging problems that include: cooperative motion control strategies of a fleet of autonomous vehicles in the presence of complex vehicle dynamics and severe acoustic-based navigation and communication constraints, where the latter are imposed by intermittent failures and latency; nonlinear control, optimal control, minimum-energy estimators, and networked control. The efficacy of some of the systems developed will be illustrated with videos from actual field tests with multiple marine robots and a human diver in the loop.

Short Bio:

A. Pedro Aguiar - PhD in Electrical Engineering from the Instituto Superior Técnico (IST), Lisbon, Portugal. Currently, Dr. Aguiar holds an Associate Professor position with the Department of Electrical and Computer Engineering (DEEC), Faculty of Engineering, University of Porto (FEUP). From 2002 to 2005, he was a post-doctoral researcher at the Center for Control, Dynamical-Systems, and Computation at the University of California, Santa Barbara (UCSB). From 2005 to 2012, he was a senior researcher with the Institute for Systems and Robotics at IST (ISR/IST), and an invited assistant professor with the DEEC of IST. Expertise in Dynamical Systems Theory, Trajectory Tracking and Path Following Techniques, Nonlinear Control, and Networked Control and Estimation. Associate Editor of IFAC Automatica.

Welcome!

Guest Lecture by Prof. Jing Sun, University of Michigan, Ann Arbor, on "Predictive Control of Integrated Power Systems for Electrified Vehicles"

4 November 2014 at 11:15-12:00
Room T3, Marine Technology Centre

Guest Lecture by Prof. Jing Sun, University of Michigan, Ann Arbor, on "Predictive Control of Integrated Power Systems for Electrified Vehicles"

4 November 2014 at 11:15-12:00
Room T3, Marine Technology Centre

Guest Lecture by Prof. Jonathan Tu, UC Berkeley, on "Data-Driven Approaches for Overcoming Temporal Sampling Rate Limitations in Particle Image Velocimetry"

15 October 2014 at 10:15-11:00
Room T3, Marine Technology Centre, Tyholt campus

Guest Lecture by Prof. Jonathan Tu, UC Berkeley, on "Data-Driven Approaches for Overcoming Temporal Sampling Rate Limitations in Particle Image Velocimetry"

15 October 2014 at 10:15-11:00
Room T3, Marine Technology Centre, Tyholt campus

ABSTRACT

Particle image velocimetry (PIV) is a powerful tool in the arsenal of measurement techniques available to fluid flow experimentalists.
The resulting velocity data are both spatially distributed and quantitative, enabling rigorous global analysis.
However, when studying fluid flows with complex temporal dynamics, the use of PIV is often constrained by limitations on the maximum sampling rate.
In this talk, I will present two data-driven approaches to dealing with this issue, leveraging techniques from control theory and signal processing to extend the capabilities of existing equipment.
I will focus specifically on the challenge of identifying characteristic flow frequencies and their associated spatial structures using sub-Nyquist-rate PIV.
The first approach that I will discuss uses slowly sampled PIV data in combination with a fast probe signal.
These data are post-processed with a Kalman smoother, which produces a time-resolved estimate of the flow field evolution.
Spectral analysis can then be done using the estimated velocity fields, for instance using dynamic mode decomposition.
I will also describe a compressed sensing approach that takes advantage of sparsity and random sampling strategies to avoid aliasing, making it possible to circumvent the Nyquist-Shannon sampling criterion.
The capabilities of each approach will be demonstrated using data collected from bluff-body wake experiments.

BIO

Jonathan Tu is currently a postdoctoral scholar at the University of California, Berkeley, where he studies the hydrodynamics of flagellar locomotion under Profs. Murat Arcak and Michel Maharbiz.
His work is part of a collaborative effort to design and manufacture millimeter-scale microbiorobots.
Previously, Jonathan studied at Princeton University, where he earned a Ph. D. working on flow control problems with Prof. Clancy Rowley.
Prior to that Jonathan attended the University of Washington, where he earned Bachelor's degrees in both Aeronautics/Astronautics and Mathematics.
His research looks to bring advanced tools from control and dynamical systems theory to bear in fluid mechanics.
In particular, he is interested in using data-driven methods such as modal decomposition, compressed sensing, and machine learning to model and control fluid mechanical systems.
 

Guest Lecture by Prof. R. Andrew Schwartz, Michigan Technological University, on Model Updating of Spinning Beam Structures for Load Characterization and Structural Health Monitoring Applications

2 February 2015 at 15:15-16:00
Room T9, Marine Technology Centre, Tyholt

Guest Lecture by Prof. R. Andrew Schwartz, Michigan Technological University, on Model Updating of Spinning Beam Structures for Load Characterization and Structural Health Monitoring Applications

2 February 2015 at 15:15-16:00
Room T9, Marine Technology Centre, Tyholt

Abstract:

Structural health monitoring (SHM) relies on models to exploit damage-sensitive features in order to identify and characterize damage.  Mechanistic models that are able to incorporate damage behavior are preferred, as they can represent damage type and severity, as well as characterize the danger posed to the structure by hypothesized damage scenarios.  Fusion of data-driven models, realized from vibrational response data, with useful mechanistic models must be achieved in order to  make use of sensor data in this way.  In addition, low-order models are preferred for SHM owing to the need for such systems to operate autonomously and in near real time.  In this study, a mechanistic model, based on spinning finite elements with damped gyroscopic and coupled flexural torsional effects, is fused with a data-driven model, based on output-only cyclo-stationary stochastic subspace identification, for spinning beam structures using an adaptive simulated annealing algorithm.  The ultimate goal of the project is to incorporate fluid-structure interaction into the mechanistic model for use in load characterization and SHM of wind turbine structures.  Related work integrating novel 2D strain-sensing skins for damage detection is also presented.


Guest Lecture by Professor Mark A. Moline, University of Delaware, USA, on applications for autonomous underwater vehicles

24 September 2014 at 16:15-17:00
Aud. T2, Marine Technology Centre, Tyholt

Guest Lecture by Professor Mark A. Moline, University of Delaware, USA, on applications for autonomous underwater vehicles

24 September 2014 at 16:15-17:00
Aud. T2, Marine Technology Centre, Tyholt

AMOS is currently hosting one of our international collaborators, Professor Mark A. Moline, from the University of Delaware, USA.

Professor Mark Moline is regarded as one of the pioneers in operation of autonomous underwater vehicles including sensors.

Professor Mark A. Moline obtained BA degree in Biology in 1986 from St. Olaf College, and PhD degree in Oceanography from the University of California, Santa Barbara in 1996. After a year-long post-doctoral fellowship at Rutgers University, Moline became a Professor at California Polytechnic State University.  During his tenure at Cal Poly, Moline received numerous national awards including the New Investigator Award from NASA, the Young Investigation Award from the Office of Naval Research and the Presidential Early Career Award for Scientists and Engineers.  In 2004, Moline established the Center for Coastal Marine Sciences and was the founding Director until 2012.  In 2010, Moline became a co-founder of the NTNU spin-off company Ecotone AS.  In 2011, Moline was named the Fulbright's Distinguished  Arctic Chair and served in that position at the University Centre in Svalbard.  In 2012, Moline became the Director of the School of Marine Science and Policy at the University of Delaware, overseeing activity of 40 faculty, 25 staff, 250 students, a satellite campus, and a regional class research vessel.  Moline has published over 150 peer-review articles on biological oceanography, marine ecology, polar biology, bioluminescence, underwater robotics, ocean observation networks, and scales of dynamics in the marine environment. 

Guest Lecture by Professor Murat Arcak, UC Berkeley, on "An Input/Output Approach to Networked Dynamical Systems"

14 October 2014 at 13:15-14:00
Room B343, Gløshaugen

Guest Lecture by Professor Murat Arcak, UC Berkeley, on "An Input/Output Approach to Networked Dynamical Systems"

14 October 2014 at 13:15-14:00
Room B343, Gløshaugen

Abstract

We will present a compositional approach that uncovers the dynamical properties of a networked system by exploiting input-output properties of the subsystems and the structure of their interconnection. This approach overcomes the complexity of a large-scale, nonlinear network model by abstracting important input-output properties from more detailed dynamical models describing the subsystems.  We will illustrate this approach with examples from synthetic biology, multi-agent systems, and traffic networks. These examples will also serve to exhibit special interconnection structures and input-output properties that are compatible with these structures. We will then present a large-scale optimization technique to search for input-output properties that certify a prescribed network performance criterion for a given interconnection.
Biosketch

Murat Arcak is a professor at UC Berkeley in the Electrical Engineering and Computer Sciences Department. He received a B.S. degree in Electrical Engineering from the Bogazici University, Istanbul, Turkey (1996) and M.S. and Ph.D. degrees from the University of California, Santa Barbara (1997 and 2000). His research is in dynamical systems and control theory with applications to synthetic biology and multi-agent systems. He received a CAREER Award from the National Science Foundation in 2003, the Donald P. Eckman Award from the American Automatic Control Council in 2006, and the Control and Systems Theory Prize from the Society for Industrial and Applied Mathematics (SIAM) in 2007. He is a member of SIAM and a fellow of IEEE.

URL: http://www.eecs.berkeley.edu/Faculty/Homepages/arcak.html


Mini-course by Prof. Manfredi Maggiore, University of Toronto, Canada, on Reduction Principles for Hierarchical Control Design

18 February 2015 at 09:00-16:00
Room B343, Electro Building B, Gløshaugen Campus

Mini-course by Prof. Manfredi Maggiore, University of Toronto, Canada, on Reduction Principles for Hierarchical Control Design

18 February 2015 at 09:00-16:00
Room B343, Electro Building B, Gløshaugen Campus

Abstract

This mini-course presents a formulation of the hierarchical control design problem for nonlinear systems. The idea in hierarchical control design is to “divide and conquer” a complex control specification by decomposing it into a hierarchy of sub-specifications, each one typically easier to enforce than the original specification. The backstepping technique for equilibrium stabilization is a popular example of hierarchical control design.

Hierarchical control specifications arise naturally in modern robotics applications. To illustrate, the path following problem for vehicle formations involves a hierarchy of two specifications: first enforce the desired formation, then make the formation follow a pre-specified path in three-space. Enforcing the formation corresponds to stabilizing a subset $\Gamma_1$ of the vehicles’ state space; making the formation follow the path corresponds to stabilizing a second subset, $\Gamma_2$, contained in $\Gamma_1$. Thus in this context, hierarchical control design corresponds to the simultaneous stabilization of two nested invariant sets $\Gamma_2 \subset \Gamma_1$.

In this mini-course a framework is proposed in which hierarchical control design amounts to the simultaneous stabilization of a finite collection of nested controlled invariant sets. I will discuss so-called reduction principles as tools to address this stabilization problem. The theory will be used to solve two problems: the design of distributed controllers solving the circular formation stabilization problem for nonholonomic vehicles, and the design of almost-global position controllers for thrust-propelled underactuated vehicles. In the context of equilibrium stabilization of lower-triangular control systems, I will show that reduction principles allow one to improve the classical backstepping technique.

Biography

Manfredi Maggiore was born in Genoa, Italy. He received the Laurea degree in Electrical Engineering in 1996 from the University of Genoa and the PhD degree in Electrical Engineering from the Ohio State University, USA, in 2000. Since 2000 he has been with the Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Canada, where he is currently Professor. He has been a Visiting Professor at the University of Roma Tor Vergata (2001) and the University of Bologna (2007-2008). His research focuses on mathematical nonlinear control, and relies on methods from dynamical systems theory and differential geometry.


Guest lecture by Ondřej Marek, VUTS Liberec, Czech Republic, on the repositioning of the flexible mechanical structures using wave-based control

18 November 2014 at 13:15-14:00
Room B343, Electro building B, Gløshaugen campus (map)

Guest lecture by Ondřej Marek, VUTS Liberec, Czech Republic, on the repositioning of the flexible mechanical structures using wave-based control

18 November 2014 at 13:15-14:00
Room B343, Electro building B, Gløshaugen campus (map)

ABSTRACT

Fast repositioning of the mechanical systems is a very actual topic especially when the systems are flexible. Every impact is exciting vibrations and when the system is low damped the residual vibrations preserve for a long time when compared to the time of repositioning. The methods which can control the flexible structures indeed exist. They are mostly feed forward methods called “input shaping”. IS when knows the natural frequencies of the system can pre-calculate the shape of the input (displacement law). These techniques work well when the system does not change its characteristics in time and when there is no disturbance. These impacts can be reduced only by methods with the feedback. The wave-based control is one of these methods. Wave-based control is a powerful, relatively new strategy that has many advantages over most existing techniques. The central idea is to consider the actuator motion as launching mechanical waves into the flexible system while simultaneously absorbing returning waves. This simple, intuitive idea leads to robust, generic, highly efficient, adaptable controllers, allowing rapid and almost vibrationless re-positioning of the remote load (tip mass). For the first time there is a generic, high-performance solution to this important problem that does not depend on an accurate system model.
The important questions are: stability, realization using real actuators (servomotors).

 

Short Bio:

Ondrej Marek have received his PhD degree in Mechanics of Solids, Deformable Bodies and Continua at the Department of Mechanics and Mechatronics at the Czech Technical University in Prague (CTU in Prague) in 2014. Currently he works as a researcher in research institute “VUTS Liberec” in Liberec, Czech Republic. His main research interests are in theory and control of vibrating structures. His dissertation thesis is called “The position control of flexible structures using wave-based method”.
 

Guest Lecture by Prof. Martin Kühn, ForWind and University of Oldenburg, Germany, on wake effects in the German offshore test field »alpha ventus« measured with synchronised long-range lidar windscanners

19 November 2014 at 15:30-16:15
Room T6, Marine Technology Centre

Guest Lecture by Prof. Martin Kühn, ForWind and University of Oldenburg, Germany, on wake effects in the German offshore test field »alpha ventus« measured with synchronised long-range lidar windscanners

19 November 2014 at 15:30-16:15
Room T6, Marine Technology Centre

Abstract

The flow conditions in the planned very large offshore wind farms with hundreds of multi-megawatt wind turbines sited in wind farm clusters will differ in various aspects significantly from what is presently known on wake effects of small to medium-scale wind farms. The contribution will provide an overview on the results gathered during the measurement campaign in German offshore test site »alpha ventus« with two scanning long-range lidars on »Fino1« and one scanning lidar on the substation conducted from summer 2013 till spring 2014.

In addition, a brief summary of the research on wind physics at ForWind – Oldenburg and on the development of novel wind farm control concepts will be given.

figure 1

 

 

 

Figure 1: Two dimensional scan of the wind farm flow at "alpha ventus".

Two azimuthal scans performed with long range lidars based on the substation in »alpha ventus« (marked by green box) and »Fino1« are visualized in the background. The highlighted section shows the horizontal component of the farm flow calculated from the two scans. Wakes of three rows of turbines are clearly visible.


Guest Lecture by Prof. Nikos A. Aspragathos, University of Patras, on the manipulation of non-rigid objects of sheet form

29 September 2014 at 13:15-14:00
Room G-144, Gløshaugen campus

Guest Lecture by Prof. Nikos A. Aspragathos, University of Patras, on the manipulation of non-rigid objects of sheet form

29 September 2014 at 13:15-14:00
Room G-144, Gløshaugen campus

The guest lecture is part of the Lighthouse Robotics project at the IME-faculty ("Fyrtårnsprosjektet Robotikk").

Summary

Definitions and classification of non-rigid objects of sheet form. Applications in services and industry for robotic manipulation of deformable objects.  Characteristics and physical properties of deformable objects.  Experimental evaluation of the most critical configuration parameters.

Robot abilities for deformable objects manipulation. Approaches for manipulation of sheet form non-rigid objects. Manipulation of low bending rigidity objects such as sheet of thin foam or thin plastic. State of the Art on sensor -based model free motion planning and control methods for robotic manipulation of low bending rigidity objects.

Manipulation of very low bending rigidity objects (Fabrics).  Fabric placement by robot manipulators without additional sensors.  Visual servoing for fabric folding and intelligent hierarchical control scheme for robotic sewing of fabrics. Development of hands with underactuated fingers and their motion sequences for fabric grasping.  Methods developed for reducing fabric configurations and configuration recognition towards fabric unfolding. Human-robot interaction for fabric manipulation based on force and vision feedback.

Future work trends and perspectives.

 

Short CV

Professor Nikos A. Asprgathos leads the Robotics Group in Mechanical and Aeronautics Engineering Department, University of Patras, Greece. His main research interests are robotics, intelligent motion planning and control for mobile robots, as well as dextrous manipulation of rigid and non-rigid objects, micro-manipulation, knowledge-based design,  metamorphic manipulators, industrial automation, and computer graphics.

He is reviewer in more than 30 Journals and more than 20 conferences, member of the editorial board of the Mechatronics Journal, Robotica, and ISRN Robotics. He published more than 70 papers in Journals and more than 130 papers in conference proceedings. He was and is currently involved in research projects funded by Greek and European Union sources.

Guest lecture by Professor João Borges de Sousa, University of Porto, on networked vehicles for maritime operations: design and implementation

14th January 2014 at 13:15-14:30
Room B343, Gløshaugen, Elektro Bld. D

Guest lecture by Professor João Borges de Sousa, University of Porto, on networked vehicles for maritime operations: design and implementation

14th January 2014 at 13:15-14:30
Room B343, Gløshaugen, Elektro Bld. D

Professor Sousa's research group is a collaborator on AMOS, with a focus on coordinated operations involving UAVs (unmanned aerial vehicles) and AUVs (autonomous underwater vehicles).


Guest Lecture by Professor Louis L. Whitcomb and Dr Christopher McFarland, Johns Hopkins University, USA, on underwater operations and robotics

7 August 2014 at 11:15-12:00
Room T3, Marine Technology Centre, Tyholt

AMOS is welcoming members of a world leading research group on underwater robotics.

Guest Lecture by Professor Louis L. Whitcomb and Dr Christopher McFarland, Johns Hopkins University, USA, on underwater operations and robotics

7 August 2014 at 11:15-12:00
Room T3, Marine Technology Centre, Tyholt

AMOS is welcoming members of a world leading research group on underwater robotics.

Professor Louis L. Whitcomb and Dr. Christopher McFarland are returning from an expedition in the arctic oceans after successful testing the new ROV Nereid-UI's first under-ice deployments.

News note from Louis

Dear Colleagues:

We are presently at 71° 10.627′ N 17° 19.843′ E in transit to Tromso, Norway, after conducting Nereid-UI's first under-ice deployments during the July 2014 R/V Polarstern PS86 expedition at 86° N 6 W° in the Arctic Ocean - near the Aurora hydrothermal vent site on the Gakkel Ridge approximately 200 km NE of Greenland.  We conducted 4 dives to evaluate and develop Nereid-UI's overall functioning and its individual engineered subsystems including energy storage, propulsion, ice-relative underwater navigation, fiber-optic tether, underwater acoustic telemetry, radio-frequency (RF) telemetry, command and control, acoustically controlled semi-autonomous operation, buoyancy, emergency localization, and launch/recovery operations.  We also conducted Nereid-UI's first science operations including targeted high-resolution vertical profiling; constant distance from ice or constant depth survey, primarily for IR/radiance measurements and electronic still camera imaging, multibeam under-ice topography mapping, high-definition optical imaging of the upper water column, under-ice biology, and under-ice topography.

Each of the four dives commenced with deployment of the acoustic telemetry and ranging package from the ship's moon pool. Nereid-UI and its mated tow-body/depressor were then deployed from Polarstern‘s starboard deck just aft of the CTD station into an open pool of water created by the ship's main propellers and bow/stern thrusters.  After preliminary checkout of Nereid-UI on the surface, Nereid-UI was piloted to 26 m depth while the depressor/towbody was lowered to about 23 m depth, where a full checkout of all vehicle systems was completed.

After remote-controlled release of the tow-body from the depressor, Nereid-UI was piloted at 40 m depth to its planned site of operation under a floe. Dead-reckoning (Ice-locked Doppler sonar and north-seeking gyrocompass) complemented by acoustic ranging provided excellent navigation throughout the dives, and supports closed-loop control of heading, depth, and XY position relative to the ice. Science operations included multibeam transects of under-ice topography, precision vertical profiles for the bio-sensor suite and IR/radiance sensor suite, IR/radiance/multibeam transects at constant depth interlaced with vertical profiles and upward-looking digital still-camera surveys of the ice, inclluding areas rich with algal material.   The fiber-optic tether remained intact throughout most of all 4 dives.  Consistent with the Nereid-UI concept of operations, in 3 of 4 dives the fiber-optic tether eventually failed, and the vehicle was then commanded acoustically in a series of short-duration maneuvers to return to Polarstern before surfacing in an open pool on Polarstern's starboard side.   RF communications enabled the pilot to maneuver the vehicle around small surface floes to the ship's side for recovery.

These preliminary dives were each 5 hours in duration, with Nereid-UI ranging up to 800 m from Polarstern at a maximum depth of 45 m and traveling up to 3.7 km under the moving sea ice.

The Woods Hole Oceanographic Institution and collaborators from the Johns Hopkins University and the University of New Hampshire have developed for the Polar Science Community a remotely-controlled underwater robotic vehicle capable of being teleoperated under ice under remote real-time human supervision.  The Nereid Under-Ice (Nereid-UI) vehicle will enable exploration and detailed examination of biological and physical environments including the ice-ocean interface in marginal ice zones, in the water column of ice-covered seas, at glacial ice-tongues, and ice-shelf margins, delivering realtime high-definition video in addition to survey data from on board acoustic, optical, chemical, and biological sensors. The vehicle employs a novel lightweight fiber-optic tether that will enable it to be deployed from a ship to attain standoff distances of up to 20 km from an ice-edge boundary under the real-time remote control of its human operators, providing real-time high-resolution optical and acoustic imaging, environmental sensing and sampling, and, in the future, robotic intervention. The goal of the Nereid-UI system is to provide scientific access to under-ice and ice-margin environments that is presently impractical or infeasible.

The Nereid-UI at-sea team on Polarstern PS86 is Christopher R. German (science lead and PI of the NOAA grant that funded these PS86 Nereid-UI ops, and CO-PI on the Nereid-UI NSF MRI development grant), Michael V. Jakuba (Nereid-UI engineering and ops lead), John Bailey, Steve Elliott, Christopher Judge, and Stefano Suman, all from WHOI, and Christopher McFarland and myself from JHU.  I am a CO-PI of Nereid-UI NSF MRI Grant that funded Nereid-UI's development.  Christopher McFarland is the lead developer of the ship-based navigation system that we used to remotely guide Nereid-UI, submerged under moving ice, back to the ship.

Nereus development was supported by NSF OPP (ANT-1126311), WHOI, James Family Foundation, and George Frederick Jewett Foundation East. Nereid-UI PS86 operations were supported by NOAA-OER, PS86 Chief Scientist Antje Boetius, and the Captain and Crew of the R/V Polarstern PS86.

We are grateful to the many engineers and scientists who supported the Nereid-UI development and operations efforts before and during this expedition including the WHOI Deep Submergence Operations Group and the WHOI Acoustic Communications Group. The ships officers, crew, science party, and Chief Scientist Dr. Antje Boetius have been wonderful.

More information about Nereid-UI and the multiple scientific and engineering objectives of this expedition are available here http://www.whoi.edu/main/nereid-under-ice and here http://www.marum.de/en/ARK-XXVIII3.html

Our present location is available here: http://www.awi.de/en/infrastructure/ships/polarstern/where_is_polarstern .


Guest lecture by Professor Gianluca Antonelli, University of Cassino and Southern Lazio, on "Control problems for floating-base manipulators"

23 April 2014 at 10:15-11:30
EL6, Elektro, Gløshaugen

Guest lecture by Professor Gianluca Antonelli, University of Cassino and Southern Lazio, on "Control problems for floating-base manipulators"

23 April 2014 at 10:15-11:30
EL6, Elektro, Gløshaugen

Abstract

The University of Cassino is currently involved in two projects considering the use of floating base manipulators. One scenario concerns autonomous aerial platforms while the other autonomous underwater vehicles. In both cases two vehicles should cooperatively grasp and transport an object. The lecture will address possible kinematic and dynamic strategies to the case study under concern. Preliminary numerical simulation and experimental results will be shown.

Biosketch

Gianluca Antonelli is an Associate Professor at the "University of Cassino and Southern Lazio''. His research interests include marine and industrial robotics, multi-agent systems, identification. He has published 32 international journal papers and more than 90 conference papers, he is author of the book "Underwater Robots'' (Springer-Verlag, 2003, 2006, 2014) and co-authored the chapter ``Underwater Robotics'' for the Springer Handbook of Robotics, (Springer-Verlag, 2008). He has been scientific responsible of the European project Co3AUVs, Associate Editor for ECHORD and researcher for ARCAS and EUROC. He served both as independent expert and reviewer for the European FP calls several times since 2006. He is chair of the IEEE RAS Chapter of the IEEE-Italy section, he has been Chair of the IEEE Robotics and Automation Society (RAS) Technical Committee in Marine Robotics. He serves/served in the Editorial Board of the IEEE Transactions on Robotics, IEEE Transactions on Control Systems Technology, Springer Journal of Intelligent Service Robotics, he is Editor for the RAS Conference Editorial Board.

URL: http://www.eng.docente.unicas.it/gianluca_antonelli