Academic literature on the topic 'Modellbygge'

Syftet med detta arbete att bygga en modell av det seglande lastfartyget WPCC. År 2021 vill Wallenius Marine att detta seglande lastfartyget ska vara i bruk. Från tidigare arbete inom detta projekt så har de geometriska formerna för seglen samt skrovet bestämts, men även ett program har gjorts som tillämpar Vortex-Lattice metoden, som beräknar kraftutvecklingen på seglen för olika anfallsvinklar. I programmet har även två olika vingkonfigurationer testats, den första enligt en baslinje och den andra enligt en rektangel. Modellen som ska göras ska kunna verifiera dessa tidigare arbeten med hjälp av ett vindtunneltest. I vindtunneltesten kommer kraftutvecklingen för olika anfallsvinklar testas för de två olika vingkonfigurationerna. De krav som ställs på modellen är att den ska hålla för vindtunneltestet samt att modellen ska möjliggöra dessa två olika vingkonfigurationer. Med hjälp av hållfasthetslära så ska seglen dimensioneras så att de tål lasten då vindtunneln brukar sin maxkapacitet på 60 m/s. För att underlätta testerna ska styrservo implementeras, vilken upprepade gånger ska ställa seglen i rätt position och ha hög noggrannhet vid varje försök. Detta bidrar till att modellen görs utan skrov för att möjliggöra att alla komponenter som behövs till styrservon ska få plats, samt för att underlätta ihopmonteringen av modellen och monteringen i vindtunneln. För att modellen ska få plats i vindtunneln kommer den konstrueras i skala 1: 267.
The purpose of this project is to build a model of the sailing cargo ship WPCC. In 2021, Wallenius Marine wants this sailing cargo ship to be in use. From previous work in this project, the geometric shape of the sails and the hull have been determined, and a program has also been made that applies the Vortex-Lattice method, which calculates the power generation on the sails for different angles of attack. In the program, two different wing configurations have also been tested, the first according to a baseline and the second according to a rectangle. The model to be made is going to verify these previous works by means of a wind tunnel test. In the wind tunnel test, the power generation for different angles of attack will be tested for the two different wing configurations. The requirements imposed on the model are that it must hold for the wind tunnel test and that the model should enable these two different wing configurations. With the help of solid mechanics theory, the sails are dimensioned so that they can withstand the load when the wind tunnel is used at its maximum capacity of 60 m/s. In order to facilitate the tests, a steering servo is implemented. The steering servo must repeatedly place the sails in the correct position and have high accuracy at every attempt. This contributes to the model being made without hull, in order to allow all components needed for the steering servo to fit and to facilitate assembly of the model and installation in the wind tunnel. In order for the model to fit in the wind tunnel, it is built in scale 1: 267.

This master thesis is one part of a project, called “StabSim”, with the purpose to develop a simulation model for the align and stabilisation system in main battle tank 122. The origin of this project is that it should be possible to make control analysis without risking any hardware. Besides that it will be easy to change components in order to investigate the behaviour of the system.

The report includes modelling of tower and weapon mechanics and also the modelling of the synchronous motors, which control these. There is also a discussion whether the model can be reduced in order to receive a less stiff system.

To get a proper system the models needs many parameters. Some of them are unknown and that’s why this report includes methods to estimate them. Measurements have then been done on a main battle tank, and requisite parameters have been estimated.

This master thesis holds a modelling in Simulink for a physical model of a main battletank tower, a three-phase induction motor and some mechanics. The aim of this work is to connect an earlier project at AerotechTelub, named StabSim to another called Eldris. In StabSim it has been made a Simulink model of the align and stabilisation system in a main battle tank 122 and in Eldris it has been build a physical model of a main battle tank tower.

In this thesis the models that differs between Eldris and a real tower is changed in StabSim, and the parts that only exist in Eldris is added, for example a torque generating system which purpose is to make the model to behave like a real tower in control application, although it only has half the inertia as a real tower.

The thesis even includes proposing a calculation of the torque that the torque generating system will actuate at the model.

This master thesis covers the development of an automatic tuning process for the existing speed controller for drive systems. The drive systems are resonant two-mass systems where a motor is used to drive a load connected by a shaft. The developed method relies heavily on system identification and the construction of a complete mechanical model of the process. With this approach, the common problem with poor load speed control that derives from measuring only the motor speed can be addressed and solved for a majority of such processes.

The automatic tuning method has along with general test functions been implemented in a complete tool for automatic tuning, testing and performance evaluation and reporting for drive systems.

This study investigates how upper secondary school students constitute relations between the environment and humanity. The aim of the study is to analyse relations that emerge between and within the Earth´s major systems (humanity included) and how these relations are composed when students are faced with a fictional decision of consuming a pair of jeans.                        Using workshop as a data collection method, students creatively visualize their discussions through participatory modelling in groups. The results of the study are based on the analyses of the concluding presentations of the completed models. The results show difficulties in submitting relations between the three dimensions of the concept of sustainable development together with a dualistic worldview, indicating a lack of complexity in the presentations. Therefore, a gap can be identified between the empirical results and the aims of education for sustainable development (ESD) that, according to the Ministry of Education and Research, should be a part of Swedish upper secondary education. In addition, a gap between the steering documents for the Swedish upper secondary schools and the UNESCO guidelines on ESD is revealed, consisting of the latter more distinctly promoting systems thinking and embracing pluralism.                                                                  Three national programmes are represented in the study; social science, science and economics. Differences between the three are established. Groups with a focus on social science present complexity to higher extent than groups on science orientation. Groups with a focus on economics present least complexity in their presentations.