Modelling and Development of a Magnetic Levitation System: for Fault-Tolerance Demonstration of a Hard Real-Time Avionics

Magnetic levitation technology has evolved as an important consideration in designing and developing systems with frictionless guidance and suspension. The main objective undertaken in this thesis is to create a model and develop a magnetic levitation system capable of levitating and moving a ferromagnetic object by means of a real-time controlled magnetic field generated by a set of electromagnets. An analytical mathematical model describing the electromechanical dynamics of the system is obtained and identified. In addition, a simplified and more efficient mathematical model based on experimental data is investigated. Three different vertical direction controllers based on different nonlinear control theories: Jacobian Linearization, Feedback Linearization and Sliding Mode Control, are proposed and validated. The mechanical components of a three-dimensional magnetic levitation system with simple position control scheme are designed and analyzed. A concept of digital control system consist of microcontroller based digital controller, position sensor system and digitally controlled power drivers is developed and implemented to track a reference position signal. Finally, the procedure of integrating the designed system into a suggested avionics system concept to estimate the performance of the avionics system's fault-tolerance capability is discussed as a basis for future work.

The author received his M.Sc. degree in Electrical Engineering with specialization in Automation and Control from the University of Kaiserslautern, Germany in 2010. In the same year he has started his scientific and academic activities as a research assistant at the Chair of Aerospace Information Technology at the University of Würzburg, Germany.