The frictionless electromagnetic control system
The Magnetic Levitation System (MLS) is a nonlinear, open-loop, unstable time varying frictionless dynamical system. The basic principle of MLS operation is to apply the voltage to an electromagnet to keep a ferromagnetic sphere levitated. Moreover, the sphere can follow a desired position value varying in time. The coil current is measured to explore identification and multi loop or nonlinear control strategies. To levitate the sphere a real-time controller is required. The equilibrium stage of two forces (the gravitational and electromagnetic) is maintained by the controller to keep the sphere in a desired distance from the magnet.
The system is fully integrated with MATLAB/Simulink and operates in the real-time in MS Windows. In the case of two electromagnets the lower one can be used for external excitation or as a contraction unit. This feature extends the MLS application and is useful in robust controllers design. The PC equipped with the RT-DAC/PCI I/O board communicates with the power interface. The user can create his own controller in a fast and easy way. Another MLS variant is shown on the left. Instead of the infrared position sensoring the magnetic flux is measured.
- ferromagnetic sphere- position sensor
- current sensor
- power interface
- RTDAC/PCI I/O board with a logic stored in the XILINX chip
450x380x530 mm (right one)