Selaus koulutusohjelman mukaan kokoelmassa VäitöskirjatSchool of Energy Systems, Konetekniikka
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An experimental and theoretical investigation of power losses in planetary gearboxes
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 12.10.2018)Gearboxes based on planetary gear sets are preferred for their advantages, such as higher gear ratios, improved self-centering capabilities, kinematic flexibility, favorable bearing support conditions and higher power ... -
Applications of the 4R method for the fatigue assessment of welded joints considering different steels, joint types, post-weld treatments, and load conditions
Acta Universitatis Lappeenrantaensis : 1172 (Lappeenranta-Lahti University of Technology LUT, 10.12.2024)The use of high-strength steels (HSS) and ultra-high-strength steels (UHSS) is a way to reduce the mass of a structure while increasing mechanical performance. However, a high strength-to-weight ratio does not guarantee ... -
Artificial intelligence : a modern approach to increasing productivity and improving weld quality in TIG welding
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 29.07.2021)Recent years have seen the welding industry facing demands for improved productivity and efficiency together with simultaneous enhancement of the quality of welded structures. The welding industry has met these challenges ... -
Assessment of weld root fatigue strength of load-carrying fillet welded joints using notch stress approaches and finite element analysis
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 21.11.2023)This thesis uses nominal and notch stress concepts to evaluate the fatigue strength of loadcarrying fillet welded joints (LCFWJs) made of high-strength steel. The study investigates the effect of different reference radii ... -
Contact modelling in multibody applications
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 08.10.2021)Multibody system dynamics (MSD) offers a reliable and easy-to-use tool to analyze the dynamics of complex systems. This approach allows for the description of equations of motion for a dynamic system that consist of ... -
Coupling multibody dynamics and hydraulic actuators for indirect Kalman filtering and real-time simulation
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 15.10.2021)The computer simulation of complex mechanical systems can be performed using multibody dynamics. Multibody models often include a description of hydraulic actuators, which can introduce numerical stiffness into the models. ... -
Dependence of manufacturing parameters on the performance quality of welded joints made of direct quenched ultra-high-strength steel
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 29.09.2018)The use of ultra-high-strength steels (UHSS) has increased in the engineering industry during past decades especially in the fields of welded structural applications where products are required to possess a specific ... -
Design, development, and multi-objective optimization of robotic systems in a fusion reactor
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 08.04.2022)Fusion is the energy source of the sun and stars, and a fusion reactor is a machine to harness the fusion energy. The heat absorbed during the operation is used to produce steam, and then electricity just like a conventional ... -
Designing printing parameters for geopolymer concrete prepared from construction and demolition waste and industrial side streams
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 24.11.2023)The high demand for construction and infrastructure materials, the reduction of global warming potential (GWP) and the European union (EU) environmental protection policy have led to the use of environmentally friendly ... -
Development of continuum beam elements for the Achilles tendon modeling
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 27.01.2023)Finite element analysis is a robust and effective tool for studying soft tissues and living systems. It can analyze them despite their sophisticated forms, and the results provide crucial information. However, the computational ... -
Development of learning methodology of additive manufacturing for mechanical engineering students in higher education
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 07.07.2021)The main aim of this thesis was to research the learning of additive manufacturing (AM) and the impact of using multiple AM technologies as a form of learning. The goal was to develop a new methodology for learning additive ... -
Dynamic analysis and parameter identification for robotic manipulators
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 20.11.2023)This paper presents a comparative advanced study on parameter identification and dynamic analysis of lightweight and heavy-duty robotic manipulators. The ultimate goal is to enhance the performance and control of these ... -
Dynamic analysis of flexible multibody systems using finite elements based on the absolute nodal coordinate formulation
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 19.10.2018)The computational analysis of mechanical systems has a wide array of applications and is therefore essential in many fields of modern industry. This dissertation studies the simulation of mechanical systems using the ... -
Dynamic analysis of rotating systems including contact and thermal-induced effects
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 16.10.2018)Rotor dynamics is a special field of structural dynamics focusing on the study and analysis of rotating structures. Practical applications for rotor dynamics are found in typical industrial rotating electrical machine ... -
Dynamic and thermal modeling of touch-down bearings considering bearing non-idealities
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 26.06.2020)In an active magnetic bearing (AMB) supported rotor, the touchdown bearings support the rotor in case of an electromagnetic field failure or a fault in the control system. In this work, a dynamic and thermal model of ... -
Ecodesign of Construction and Demolition Waste-Derived Thermoplastic Composites
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 12.12.2020)The use of recycled materials in composites has been studied since the 1990s. Research has traditionally focused on technical properties, as well as the recyclability of materials. How these composites should be used or ... -
Effects of unbalanced magnetic pull on rotordynamics of electric machines
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 21.05.2021)The unbalanced magnetic pull (UMP) that results from air-gap eccentricity can present a potential risk to the lifetime and dynamic stability of rotating electric machines. Nevertheless, a method to identify the effects of ... -
Extended reality-enabled smart manufacturing in multi-robot welding applications
Acta Universitatis Lappeenrantaensis : 1210 (Lappeenranta-Lahti University of Technology LUT, 01.07.2025)Enhancing the performance of robotic welding automation is crucial to achieve high quality and flexibility in high-variation, low-volume welding production, particularly for small and medium enterprises. However, there is ... -
Fast and accurate simulation of fluid power circuits in the presence of small volumes using advanced methods and models for numerical stiffness elimination
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 02.06.2023)The modeling and simulation of fluid power systems are essential parts of the real-time simulation of virtual prototypes of mobile working machines. In several cases, in the dynamic simulation of such fluid power systems, ... -
Faster than real-time simulation of fluid power-driven mechatronic machines
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 01.06.2021)The level of automation of mechatronic machines, such as excavators, logging harvesters or fluid power-driven cranes, has increased significantly over the past few decades. In the machine industry, this led to the emergence ...