Title: Magnetically suspended balance beam with disturbances: a test rig for non-linear output regulation

Authors: Zongli Lin, Matthias Glauser, Tingshu Hu, Paul E. Allaire

Addresses: Charles L. Brown Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA 22904–4743, USA. ' Charles L. Brown Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA 22904–4743, USA. ' Department of Electrical and Computer Engineering, University of Massachusetts, Lowell, MA 01854, USA. ' Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904–4746, USA

Abstract: This paper presents an experimental test rig for non-linear output regulation. This experimental setup consists of a beam free to rotate on a pivot at its centre of mass, and stabilised by two active electromagnets located at each end of the beam. The rotation of the beam is measured by a non-contacting displacement sensor. A motor with unbalance weight is mounted on a track on top of the beam. This mounted motor serves as an exosystem in the problem of output regulation. By moving the motor position along the track and adjusting the motor rotational speed, constant and sinusoidal disturbances of different frequencies and magnitudes can be imposed on the system to test controllers. The input output characteristics of the active electromagnets are non-linear and are difficult to be determined precisely. The air gaps between the beam and the electromagnets are narrow. These properties of the setup make it a good platform for testing non-linear output regulation controllers, including robust output regulation and output regulation under the actuator and state constraints.

Keywords: nonlinear output regulation; constrained control; active magnetic bearings; exosystems; control design; dynamic modelling.

DOI: 10.1504/IJAMECHS.2008.020833

International Journal of Advanced Mechatronic Systems, 2008 Vol.1 No.1, pp.2 - 9

Published online: 17 Oct 2008 *

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