Master-slave mechanism synchronized by three-phase electrostatic induction

In some environments, electromagnetic motors cannot be used because of the strong electromagnetic field they produce. Examples of such environments are inside magnetic resonance imaging (MRI) devices and inside vacuum chambers with presence of electron beams. In such cases, an electromagnetic motor can be replaced by a DEMED (dual excitation multiphase electrostatic drive), which is a high power linear electrostatic motor, whose capability to operate in such environments has been proven by past studies. Since human hands cannot perform any task in these environments, they must be replaced by a master-slave system with manipulators controlled from outside the environment. However, to realize a master-slave system with an intuitive interface, the system must incorporate additional sensors and controllers, which makes the system more complicated. A simple master-slave mechanism comprised of two DEMED type electrostatic motors is introduced in this paper. The two motors are passively synchronized by three-phase electrostatic induction, and thus no additional sensors are necessary. Feasibility of the synchronization was confirmed by an experiment, and the maximum attainable speed was 0.1 mm/s.