New Concepts for Low-Cost Mechatronics: Magnetic Bearing Example

Abstract

Mechatronic systems typically combine mechanical components with controllers and electro-mechanical actuators, as implied in the word “mechatronics”. Controller input and output are signals. The other components involve the flow of energy (mechanical or electrical). By their very nature, such energy interactions are not unidirectional, but bidirectional.As an example, a mechanical part moved by an electromagnet will itself exert a reciprocal influence back into the electrical system. Such effects often tend to be dismissed as unwanted because they do not occur in the unidirectional signal-flow patterns of control systems.The new approach here aims at taking advantage of such interactions. It is shown that the electromagnet of the example above can, in addition to its task as a force actuator, be used simultaneously as a cheap sensor for measuring displacements, thus contributing to a low cost solution. Other examples are conceivable.Magnetic bearing concepts and experiments based on this idea are presented. Application of this concept results in a substitution of hardware through software.