Fabrication of a Three-dimensional Force Measurement System Using Double Series Magnetic Suspension

:Double series magnetic suspension is applied to force measurement. In a double series magnetic suspension system, two floators are suspended with a single electromagnet. When the position of the second floator is regulated, for example by PID control, the second floator is maintained at the original position against an external force acting on it whereas the first floator displaces in proportional to the force. Therefore, the force acting on the second floator can be estimated for the displacement of the first floator. This principle of force measurement was applied to single-dimensional force measurement. In this work, an apparatus for three-dimensional force measurement is designed and fabricated. An individual three-axis control is applied to the apparatus to achieve noncontact suspension. Then, three-dimensional force measurements are carried out to study the performances of the fabricated apparatus.