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Nguyen, Hoang Nam Du; Huynh, van Khang & Robbersmyr, Kjell Gunnar
(2023).
Current and stray flux sensors for anomaly detection in PMSM drive based on gradient boosting machine.
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Pretto, Riccardo; Dayal, Aveen; Oghbasilasie Haile, Yonas; Amendola Netto Andrade, José; Cenkeramaddi, Linga Reddy & Robbersmyr, Kjell Gunnar
[Vis alle 7 forfattere av denne artikkelen]
(2023).
Motor Bearing Fault Classification using Laser Sensor and Light Weight CNN.
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Eid, Mahmoud Sayed Mahmoud; Huynh, van Khang; Senanayaka, Jagath Sri Lal; Robbersmyr, Kjell Gunnar & Panadero, Ruben
(2023).
A two-stage Fault Diagnosis Scheme of Partial Demagnetization Faults in PMSMs with Low Labelled Rates.
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Kandukuri, Surya Teja & Robbersmyr, Kjell Gunnar
(2021).
Analytics for asset integrity management in wind farms (AIMWind).
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Nyberg, Svein Olav Glesaaen; Robbersmyr, Kjell Gunnar; Holm, Jan Andreas & Sanfilippo, Filippo
(2021).
Effects of Material Selection on Adhesion between glass and aluminium pre-recorded video for digital attendees.
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Wæhle, Andreas; Nilsen, Jørgen; Tollevik, Sigurd; Rogne, Nora; Westbye, Stian & Robbersmyr, Kjell Gunnar
(2021).
The culture of product development in student organizations.
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Jakobsen, Mette Mo; Tørdal, Sondre Sanden; Klausen, Andreas; Robbersmyr, Kjell Gunnar & Tyapin, Ilya
(2021).
Product development and project-based learning in Mechatronics, in the context of digitization and sustainability.
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Wæhle, Andreas Otter; Rogne, Nora; Westbye, Stian; Nilsen, Jørgen; Tollevik, Sigurd & Robbersmyr, Kjell Gunnar
(2021).
How to succeed with volunteers on the basis of commitment and ownership.
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Husebø, Arild Bergesen; Huynh, Khang; Robbersmyr, Kjell Gunnar & Klausen, Andreas
(2021).
Classification of Mechanical Fault-Excited Events based on Frequency.
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Nyberg, Svein Olav Glesaaen; Robbersmyr, Kjell Gunnar; Holm, Jan Andreas & Sanfilippo, Filippo
(2021).
Static Tensile Experiments on Adhesion between Aluminium Profiles and Glass.
Vis sammendrag
In this work, we study the effects of the adhesion between aluminium profiles and glass from a static tensile perspective. A series of stretch curves from a 2016 experiment are analysed from their derivatives to find their points of float and maximum load bearing. The variable factors in this experiment are glass type, and type of connection: edge gluing, side (fugue) gluing, and excessive fugue gluing, which we have named fugue-edge. The stretch data gives us four quantities to analyse and compare: displacement and load at respectively float and at max load.
We first display the results by simply comparing factor group against factor group. Whit this tool, only a few significant conclusions may be found. We then look at the more powerful statistical tools of linear regression and Anova (analysis of variance), explain these tools, and then draw conclusions about which factors are significant, and then about the size of the effect on the four variables under study. This forms the basis for our recommendation to window producers on where to focus their attention for the strongest possible glass-frame system.
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Knausgård, Kristian Muri; Skar, Siv; Sanfilippo, Filippo; Buldenko, Albert; Lindheim, Henning & Lunde, Jakob
[Vis alle 8 forfattere av denne artikkelen]
(2021).
Branch-Manoeuvring Capable Pipe Cleaning Robot for Aquaponic Systems.
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Aquaponic systems are engineered ecosystems combining aquaculture and plant production. Nutrient rich water is continuously circulating through the system from aquaculture tanks. A biofilter with nitrifying bacteria breaks down fish metabolism ammonia into nitrite and nitrate, which plants and makes the aquaculture wastewater into valued organic fertiliser for the plants, contenting essential macro and micro elements. At the same time, plants are cleaning the water by absorbing ammonia from the fish tanks before it reaches dangerous levels for the aquatic animals. In principle, the only external input is energy, mainly in the form of light and heat, but fish food is also commonly provided. Growing fish food is potentially feasible in a closed loop system, hence aquaponic systems can possibly be an important source of proteins and other important nutrition when, for example, colonising other planets in the future. Fully autonomous aquaponic systems are currently not available. This work aims at minimising manual labour related to cleaning pipes for water transport. The cleaning process must be friendly to both plants and aquatic animals. Hence, in this work, pure mechanical cleaning is adopted. A novel belt-driven continuum robot capable of travelling through small/medium diameter pipes and manoeuvring branches and bends, is designed and tested. The robot is modular and can be extended with different cleaning modules through an interface providing CAN-bus network and electric power. The flexible continuum modules of the robot are characterised. Experimental results demonstrate that the robot is able to travel through pipes of diameter 50 mm to 75 mm, and also capable of handling T-branches of up to 90 degrees.
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Sanfilippo, Filippo; Thorstensen, Rein Terje; Jha, Ajit; Jiang, Zhiyu; Knausgård, Kristian Muri & Robbersmyr, Kjell Gunnar
(2021).
A Perspective of Road Infrastructure and Bridges Digital Twins.
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Noorsumar, Gulshan; Robbersmyr, Kjell Gunnar; Rogovchenko, Svitlana & Vysochinskiy, Dmitry
(2021).
An overview of Data Based Predictive Modeling Techniques used in Analysis of Vehicle Crash Severity.
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Noorsumar, Gulshan; Rogovchenko, Svitlana; Robbersmyr, Kjell Gunnar; Vysochinskiy, Dmitry & Klausen, Andreas
(2021).
A Novel Technique for Modeling Vehicle Crash using Lumped Parameter Models.
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Attestog, Sveinung; Huynh, Van Khang & Robbersmyr, Kjell Gunnar
(2020).
Improved Quadratic Time-Frequency Distributions for Fault Detection in Transient States.
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This paper aims to improve quadratic time-frequency distributions to adapt condition monitoring of electrical machines in transient states. Short-Time Fourier transform (STFT) has been a baseline signal processing technique for detecting fault characteristic frequencies. However, limits of window sizes due to loss of frequency- or time-resolution, make it hard to capture rapid changes in frequencies. Within this study, Choi-Williams and Wigner-Ville distributions are proposed to effectively detect peaks at characteristic frequencies while still maintaining low computation time. The improved quadratic time-frequency distributions allow for generating spectrograms of a longer lasting data signal and capturing multi-component signals with a better separation of the components than STFT. Further, the time resolution of the spectrograms generated by the proposed method is not affected by the window size. The effectiveness of the proposed methods is numerically verified from the data of an in-house test setup.
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Senanayaka, Jagath Sri Lal; Huynh, Khang & Robbersmyr, Kjell Gunnar
(2019).
Electromagnetic and Vibration Modelling of an Electric Powertrain for a Simulation-driven Fault Diagnosis System.
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Attestog, Sveinung; Huynh, Khang & Robbersmyr, Kjell Gunnar
(2019).
Modelling Demagnetized Permanent Magnet Synchronous Generator for Fault Diagnosis
.
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Prediction of the lifetime for transformers is very important for maintenance and asset management. Finite element analysis was performed on a 5 MVA distribution transformers with aluminium foil-type windings and voltage rating 6600 V/23000 V. Electromagnetic modelling is implemented on the full three-phase transformer to calculate distributed losses, taking the skin effect into account. To reduce the computational burden, the distributed losses in one phase are used to analyse temperature rise in one phase of the transformer. The temperature rise results were used to determine the ageing rate of the transformer. Further, the influence of ambient temperature and cooling on the temperature rise and ageing rate of the transformer is numerically investigated.
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Hemmer, Martin; Robbersmyr, Kjell Gunnar; Waag, Tor Inge; Meyer, Thomas J. J.; Albrigtsen, Rolf & Pedersen, Torfinn
[Vis alle 7 forfattere av denne artikkelen]
(2018).
Rib-Roller Wear in Tapered Rolling Element Bearings: Analysis and Development of Test Rig for Condition Monitoring.
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Robbersmyr, Kjell Gunnar & Knausgård, Kristian Muri
(2018).
Studentprosjekter 2018.
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Robbersmyr, Kjell Gunnar & Ottestad, Morten
(2018).
Mekatronikk.
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Robbersmyr, Kjell Gunnar; Choux, Martin Marie Hubert; Zhou, Jing & Knausgård, Kristian Muri
(2018).
Mekatronikk.
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Robbersmyr, Kjell Gunnar & Knausgård, Kristian Muri
(2018).
Mekatronikk.
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Noorsumar, Gulshan; Rogovchenko, Svitlana; Robbersmyr, Kjell Gunnar & Vysochinskiy, Dmitry
(2023).
Modeling, Simulation and Prediction of Vehicle Crashworthiness in Full Frontal Impact.
University of Agder.
ISSN 978-82-8427-113-2.
Fulltekst i vitenarkiv
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Attestog, Sveinung; Robbersmyr, Kjell Gunnar & Huynh, Khang
(2022).
Modelling and Detecting Faults of Permanent Magnet Synchronous Motors in Dynamic Operations.
University of Agder.
ISSN 978-82-8427-095-1.
Fulltekst i vitenarkiv
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Ali, Ahmed Mohamed Salem; Huynh, Khang & Robbersmyr, Kjell Gunnar
(2021).
Multilevel Inverters with Reduced Component Count for Energy
Systems.
Universitetet i Agder.
ISSN 978-82-8427-045-6.
Fulltekst i vitenarkiv
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Multilevel inverters (MLIs) have gained increasing interest for advanced energy-conversion systems with a wide range of voltage levels, due to their attractive features of low harmonic contents, low dv/dt stress, low filtering requirements, low switching frequency, low electromagnetic interference (EMI), and employing low-rated semiconductor devices for producing high voltages. Further, some MLIs have a modularity feature, facilitating voltage and current scalability with high redundancy in switching states, allowing for fault-tolerant operations. The mentioned features are directly related to the number of generated voltage levels. However, enlarging level count renders challenges of requiring massive component counts, including DC sources, capacitors, power diodes, switches, inductors, and transformers. The high count of components negatively affects the size, cost, efficiency, lifespan, reliability, complexity of MLI-based energy conversion systems. Thus, proposing novel MLIs, which can enlarge the voltage level number with a low component count, is currently one of the most attractive topics in this research theme.
In this dissertation, four three-phase topologies are proposed to mitigate the aforementioned shortcomings. Two transformerless topologies are proposed for low- and medium voltage applications, while two transformer-based topologies are intended for medium- and high-voltage applications. The proposed topologies have the key features of being capacitor-, diode-free, and low counts of DC sources, switches, and transformers. Further, three of them have a high modularity degree, allowing for higher voltage operations without increasing the voltage stress across the switches. The working principle of the proposed topologies are theoretically demonstrated, numerically verified, and experimentally validated through an in-house experimental setup. The effectiveness of the proposed topologies is proven through detailed comparative studies regarding component counts and voltage ratings. The proposed topologies are briefly described in this dissertation, while detailed explanations and results can be found in the appended papers.
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Munyazikwiye, Bernard & Robbersmyr, Kjell Gunnar
(2020).
Mathematical Modelling and Analysis of Vehicle Frontal Crash using Lumped Parameters Models.
07 Media.
ISSN 978-82-7117-961-8.
Fulltekst i vitenarkiv
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Senanayaka, Jagath Sri Lal & Robbersmyr, Kjell Gunnar
(2020).
Online Condition Monitoring of Electric Powertrains using Machine Learning and Data Fusion.
07 Media.
ISSN 978-82-7117-971-7.
Fulltekst i vitenarkiv
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Hemmer, Martin & Robbersmyr, Kjell Gunnar
(2020).
Condition Monitoring Methods for Large, Low-speed Bearings.
Universitetet i Agder.
ISSN 978-82-7117-960-1.
Fulltekst i vitenarkiv
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Kandukuri, Surya Teja; Robbersmyr, Kjell Gunnar & Huynh, Khang
(2018).
Health Monitoring of Pitch and Yaw Systems in Offshore Wind Farms.
Universitetet i Agder.
ISSN 978-82-7117-891-8.
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Knausgård, Kristian Muri & Robbersmyr, Kjell Gunnar
(2018).
Studentprosjekter - innhenting og valg.
Universitetet i Agder.