Fault Tolerant Control of Magnetically Suspended Sliders.
Yasuyuki SUZUKI · TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C · 2003
While magnetically suspended sliders controlled five degrees of freedom have been used as a linear guide system for wafer transportation in clean atmosphere, three degrees of freedom controlled sliders may be applied to suspensory equipments which can move along a ceiling board without an effect of friction. Space saved and reliable suspensory equipments are very helpful for transporting handicapped people to take care of. In this paper, fault-tolerant control system using an observer for magnetically suspended sliders is discussed and the design method for the observer which can function in replacement of outputs caused by isolation of faulty sensors is proposed. In experiments, some disturbance signals are added to a displacement sensor and the responses are measured. Sensor faults are successfully detected and isolated by the designed diagnostic system for abrupt disturbances.