<p>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.</p><p>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.</p>

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 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.

<p>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. </p><p>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. </p><p>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.</p>

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.