Development of a Compact Drive System for Total Artificial Heart

Sammanfattning

Over eight decades of research into total artificial hearts (TAHs) has significantly contributed to saving end-stage heart failure patients. However, at the current stage of development TAHs have several limitations, one of them being their bulkiness. Hence this thesis, with the goal to evaluate the right pump of the TAH developed by Scandinavian Real Heart and propose a compact right drive system without consuming significantly more power than the initial system. In order to do this, the requirements for the right drive systems are evaluated and defined. These requirements are then used to develop a methodology, including a MatLab simulation, for examining and selecting motors for the drive unit of the TAH. Subsequently, the methodology and the simulation are used to identify and assess over 200 motors, as well as select 3 motors for real-world experimental analysis. The suggested motors and the initial motor are then tested in a mock circulatory loop to investigate the performance characteristics and power consumption of the motors. This is done to select the final motor for the right drive unit, as well as verify and validate the created simulation. Based on careful analysis of the mathematical models used in the simulation and presented experimental data, the simulation was accepted to be verified. However, the support for validation of the simulation was lacking, as conflicting outcome for some cases were observed between the simulation and experimental data. Furthermore, given the empirical evidence, a brushless dc motor for the right drive unit and its implementation was proposed. The proposed motor has 11% reduction in size, 20% reduction in power consumption and 34% reduction in weight compared to the initial motor. Therefore, a drive unit with the suggested motor can have a significant impact on the right pump, and potentially even the left pump. Furthermore, the utilisation of the developed simulation can ultimately result in efficient and cost-effective motor selection and provide valuable contribution to the field of drive system development for TAHs.