Prototyping and Modeling of a Temperature Controlled Sleeping Surface in a Child Pram

Sammanfattning: Accurate temperature control is important for various applications and products. This would also be the case in an electrically heated child pram, since children are vulnerable to both cold and warm environments. There will be high demands that a heated/cooled child pram maintains stable temperatures on the sleeping surface. The purpose of this thesis is to explore the feasibility of model-based control design for an electrically heated child pram. To realize this, a prototype is developed as well as a thermodynamic model of the child pram's sleeping surface. Finally, a temperature controller is proposed and later implemented on the real plant, using PI tuner on the thermodynamic model. A white-box modeling approach is selected to construct a model of the heat system. The model is developed in MATLAB Simulink/Simscape environment. Based on measured data from system testing, Simulink Design Optimization Tool is employed to estimate and verify some important parameters of the developed model. Consequently, a grey-box model of improved accuracy is generated, which is then used for controller design. The controller is tested and refined in simulation environment, before being implemented on the prototype. After this, its performance is validated against the simulated controller as well as the initial system requirements. The proposed controller shows high equivalence in simulation and in practise. It also meets thedesign specifications for this specific temperature controlled child pram. The results show that model-based design is a suitable method to develop temperature controllers for an electrically heated child pram. This thesis also highlights how to improve the accuracy of a white-box model, which plays a significant role in controller design.