Modeling and distributed control of an array magnetic manipulator


The task is to build a mathematical (simulation) model of a planar (electro)magnetic manipulator used to steer one or several iron balls in plane (the balls move by rolling, not by levitation). Such manipulator has already been built and it consists of a rectangular array of special modules, each consisting of a 2x2 electromagnets (coils with an iron core) and including the necessary amplifiers and microcontrollers (ARM Cortex M3) and communication circuits (RS485). Currently available are 4 modules, offering to build a 2x2 array of modules, hence 4x4 array of coils. See the attached photo and video or come and see it in our lab.

The manipulator is intended to be used to test various distributed control/manipulation strategies. The experiment can be viewes as an extension  of the popular ball and plate laboratory model, here the plate can be "deformed" locally. Of course, no mechanical deformation is visible, it is just the potential from which the force field is derived that is shaped here.

Whereas another student project is oriented towards finalizing the design of the hardware and working on the firmware, the proposed project aims at a bit more theoretical (or rather computing oriented) part: modeling and model-based control design.

Modeling will be done using Comsol Multiphysics software tool for Finite Element Modeling (FEM) but lumped-system approximation will be searched for to allow for model-based control design. The outcomes of the simulation might also be relevant for possible design modifications and optimizations.

Control design will address several scenarios such as manipulation of a single ball from one position to another (and back) as fast as possible, with no overshoot; following precisely a precomputed trajectory such as the figure eight trajectory; driving two (or more) balls simultaneously so that they come together and then split apart.

Contact person: 
Zdeněk Hurák
Contact person: 
Jiří Zemánek
Video: Module for distributed planar magnetic manipulation
Image: Modul for planar magnetic manipulation
Image: Visualization of an array of modules for magnetic manipulation