磁気浮上形位置決め機構の設計法 : 第3報, 磁気浮上系の安定性と非線形性の近似的線形化

抄録

The stability criteria based on the root locus method in the magnetically suspended positioning mechanism with six degrees of freedom were derived using characteristic matrices. These describe the linear characteristics of the mechanism including the driven tetrahedron armature with load mass, controller, displacement sensors and magnetic actuators. The nonlinear electromagnetic force was approximately linearized. From these were derived linear expressions of dynamic characteristics on every equilible position, and was shown how every real parameter affects the system characteristics of the mechanism. Eigenfrequency variation along with the static equilible position travel of the tetrahedron was computed using the dynamic matrix equations, and was compared with experimental data obtained from the tetrahedron model fabricated for this purpose. The results were used for the stability evaluation of the mechanism in a wide operational range.