This paper presents the concept, implementation, feedback control, and experimental verification of a noncontact magnetic manipulator that relies on a controllable array of permanent magnets to manipulate magnetized objects inside a workspace encircled by the magnets. To gain control over the aggregate magnetic field inside the workspace, the position of each magnet is independently controlled by a linear servomotor that dynamically changes the distance between that magnet and the workspace. By feedback control of the array of servomotors, the magnetic force applied to a magnetized object inside the workspace is dynamically adjusted to steer it along a desired reference trajectory. The successful steering of a small magnetic bead is demonstrated by experiments performed on a planar magnetic manipulator, designed and prototyped with six linear servomotors and six permanent magnets.
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Steering Magnetic Particles by an Array of Rotatable Permanent Magnets: Control Design and Experimental Verification
This paper presents experimental results to verify a novel concept of magnetic manipulation in which arrays of permanent magnets and electromechanical actuators generate and effectively control magnetic fields, through which, magnetic objects can be manipulated from a distance without any direct contact. This concept is realized by an experimental setup that consists of six diametrically magnetized permanent magnets actuated by rotary servomotors to control their directions, by which, the aggregate magnetic field is controlled in a planar circular workspace. To leverage this magnetic field for control of magnetic objects inside the workspace, a feedback loop must be established to command the servomotors based on the positions of these objects measured in real time. A suitable control law is developed for this feedback loop, and is verified by experiments, which demonstrate successful results. The experimental results are compared with those generated by computer simulations under similar conditions.
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- Award ID(s):
- 1941944
- PAR ID:
- 10573554
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-5536-9
- Page Range / eLocation ID:
- 474 to 479
- Format(s):
- Medium: X
- Location:
- Boston, MA, USA
- Sponsoring Org:
- National Science Foundation
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