Search results for "570"
showing 10 items of 1074 documents
Modelling of a hydro-pneumatic system for heave compensation
2017
Masteroppgave i mekatronikk MAS500 - Universitetet i Agder 2017 Testing of control systems on simulators has been found to be both cost and time e cient. To get good results from testing, a realistic response from the simulator is important. In this thesis, a mathematical model of a hydropneumatic heave compensation system for such purposes is proposed. The emphasis has been on developing a relatively simple model which is easy to run, but also accounts for important e ects like friction, non-ideal gas behaviour and temperature variation in the gas system. The mathematical model is veri ed against log data obtained from real drilling operations. Then, it is compared to simpler versions to i…
Secondary Control of a Digital Hydraulic Motor for Winch Applications
2018
Master's thesis Mechatronics MAS500 - University of Agder 2018 The reliable traditional hydraulic systems for industrial purposes is being challenged by an emerging technology called digital hydraulics. This technology shows promising improvements in regards to e ciency, especially in comparison to systems dependent on hydraulic pumps or motors with variable displacement. Digital hydraulic motors eliminate the need for a servo valve by connecting each individual motor cylinder directly to the high-pressure and low-pressure line by means of fast-acting on/o -valves. In this thesis, the potential of digital hydraulics is investigated by developing a control system intended for a digital displ…
Fault Diagnosis of an Electrical Winch based on Structural Analysis
2018
Master's thesis Mechatronics MAS500 - University of Agder 2018 This report covers development and implementation of a model-based fault-detection and fault diagnosis algorithm based on structural analysis, providing deeper knowledge of predictive maintenance, which o ers the industry increased uptime and reduced spending. Failure mode and e ect analysis are carried out at component level for an electrical winch. Construction of a Simulink model, used to verify the algorithms, are described in detail including governing equations and implementation. The basis of a structural analysis is outlined and tested on the electrical winch system. Results from the simulation model covers faults in per…
Modelling, Simulation and Control of offshore crane Develop a kinematic and dynamic crane model and study of several control designs
2018
Master's thesis Mechatronics MAS500 - University of Agder 2018 This master thesis is about Modelling, Simulation and Control of a MacGregor Active Heave Compensation (AHC) 250t crane operating on the supply vessel Gran Canyon. The crane model was developed mathematically using robot modeling theory including both kinematic and dynamic equations. This model was developed and simulated in Matlab and Simulink and further compared, where the two models showed equal results. Control designs for an offshore crane can be developed in several ways, but in this thesis the control task only concerns position control of the crane and can be divided into two control tasks. The main goal is to determine…
Dual-speed planetary gearbox for internal mounting in winch drum : design, actuation, and control
2018
Master's thesis Mechatronics MAS500 - University of Agder 2018 Konfidensiell til / confidential until 01.07.2023
Modelling and Detecting Faults of Permanent Magnet Synchronous Motors in Dynamic Operations
2022
Permanent magnet synchronous motors (PMSMs) have played a key role in commercial and industrial applications, i.e. electric vehicles and wind turbines. They are popular due to their high efficiency, control simplification and large torque-to-size ratio although they are expensive. A fault will eventually occur in an operating PMSM, either by improper maintenance or wear from thermal and mechanical stresses. The most frequent PMSM faults are bearing faults, short-circuit and eccentricity. PMSM may also suffer from demagnetisation, which is unique in permanent magnet machines. Condition monitoring or fault diagnosis schemes are necessary for detecting and identifying these faults early in the…
Modeling of Modified Vehicle Crashworthiness using a Double Compound Pendulum
2022
Vehicle crash modeling has been a challenge for researchers for several decades. Occupant injury prevention and prediction is a critical area within vehicle safety design. The modeling of material failure in structural members during a full frontal crash has been presented in this paper. This study presents a Lumped Parameter Model (LPM) with an elastic double compound pendulum replicating the impact kinematics. The model defined using Lagrangian formulation; presents a novel methodology to represent material fracture caused due to heat affected zones or welding in Ultra High Strength Steels (UHSS) in a non-linear crash event. The material fracture leads to rotation of the vehicle; presente…
Hybrid modeling and control of mechatronic systems using a piecewise affine dynamics approach
2020
This thesis investigates the topic of modeling and control of PWA systems based on two experimental cases of an electrical and hydraulic nature with varying complexity that were also built, instrumented and evaluated. A full-order model has been created for both systems, including all dominant system dynamics and non-linearities. The unknown parameters and characteristics have been identi ed via an extensive parameter identi cation. In the following, the non-linear characteristics are linearized at several points, resulting in PWA models for each respective setup. Regarding the closed loop control of the generated models and corresponding experimental setups, a linear control structure comp…
Modeling and Control of Flexible Link Manipulators
2022
Autonomous maritime navigation and offshore operations have gained wide attention with the aim of reducing operational costs and increasing reliability and safety. Offshore operations, such as wind farm inspection, sea farm cleaning, and ship mooring, could be carried out autonomously or semi-autonomously by mounting one or more long-reach robots on the ship/vessel. In addition to offshore applications, long-reach manipulators can be used in many other engineering applications such as construction automation, aerospace industry, and space research. Some applications require the design of long and slender mechanical structures, which possess some degrees of flexibility and deflections becaus…
Mathematical Modelling and Analysis of Vehicle Frontal Crash using Lumped Parameters Models
2020
A full-scale crash test is conventionally used for vehicle crashworthiness analysis. However, this approach is expensive and time-consuming. Vehicle crash reconstructions using different numerical modelling approaches can predict vehicle behavior and reduce the need for multiple full-scale crash tests, thus research on the crash reconstruction has received a great attention in the last few decades. Among modelling approaches, lumped parameters models (LPM) and finite element models (FEM) are commonly used in the vehicle crash reconstruction. This thesis focuses on developing and improving the LPM for vehicle frontal crash analysis. The study aims at reconstructing crash scenarios for vehicl…