Study on a novel contact-free planar system using direct drive DC coils and permanent magnets

To cope with the severe specification such as a concurrent realization of high accuracy and wide operating range demanded in many fields, we suggest a novel contact-free planar system that realizes the spatial motion of a plate by generating a levitation force and a thrust force at the same plane concurrently. The system utilizes an interaction between the direct drive dc coils of a common shape and the permanent magnets with a coincident polar direction and, thus, it is very facile to implement and simple to quantify the magnetic interaction. In this paper, we discuss a driving principle of the planar system including magnetic force generation mechanism, a framework for force model, governing characteristics of the levitated plate and a planar motion control of the constructed prototype. The experimental results are given to verify the derived theoretical model and the feasibility of the system.