Control results for an electromagnetically levitated vehicle prototype

Several magnetically levitated transport systems have been constructed, tested and constantly improved. Various technologies for the magnetic levitation system are also being developed and some of them use electromagnets for the vehicle levitation. In this work, a magnetically levitated vehicle prototype with four electromagnets, located in each one of the extremities of the vehicle, is studied. The vehicle levitation is achieved through the control of the gaps of these electromagnets. The constructed prototype will have independent levitation and propulsion systems; this paper considers only the magnetic levitation system. The resultant system is strongly non-linear, multivariable and open loop unstable. A MIMO controller. based on an analytical model of the vehicle, was designed in the LQG/LTR context. The performance and robustness bounds for this design were based on simulations for a similar SISO system. Although conceived in the MIMO context, the final controller resulted close to a set of decentralized SISO controllers.