Abstract
In order to study contact-free levitation systems for micromachines, our group has developed a levitation system with a millimeter-sized cylindrical rotor. The system consists of a rotor (2.0 mm φ×8 mm, 95 mg), a pair of electromagnets for levitation, two pairs of photo diodes for sensing, and an analog PD controller. The photo diodes detect axial displacements and rotation speeds of the rotor. The rotor and the electromagnets are so small that the rotor in the axial direction is passively stabilized. This paper describes closed-loop frequency responses, follow-up control characteristics, impulse responses, and rotation decay characteristics. From the results, it is found that the levitating rotor makes a very quick response because of the small mass 95 mg, and that photo diodes are useful for sensing rotation speeds.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
