Development of an Electromagnetic Micromanipulator Levitation System for Metal Additive Manufacturing Applications

Abstract

Magnetism and magnetic levitation has found significant interest within the field of micromanipulation of objects. Additive manufacturing (AM), which is the computer-controlled process for creating 3D objects through the deposition of materials, has also been relevant within the academic environment. Despite the research conducted individually within the two fields, there has been minimal overlapping research. The non-contact nature of magnetic micromanipulator levitation systems makes it a prime candidate within AM environments. The feasibility of integrating magnetic micromanipulator levitation system, which includes two concentric coils embedded within a high permeability material and carrying currents in opposite directions, for additive manufacturing applications is presented in this article. The working principle, the optimization and relevant design decisions pertaining to the micromanipulator levitation system are discussed. The optimized dimensions of the system allow for 920 turns in the inner coil and 800 turns in the outer coil resulting in a Ninnercoil:Noutercoil ratio of 1.15. Use of principles of free levitation, which is production of levitation and restoration forces with the coils, to levitate non-magnetic conductive materials with compatibility and applications within the AM environment are discussed. The Magnetomotive Force (MMF) ratio of the coils are adjusted by incorporation of an resistor in parallel to the outer coil to facilitate sufficient levitation forces in the axial axis while producing satisfactory restoration forces in the lateral axes resulting in the levitation of an aluminum disc with a levitation height of 4.5 mm. An additional payload of up to 15.2 g (59% of mass of levitated disc) was added to a levitated aluminum disk of 26 g showing the system capability coping with payload variations, which is crucial in AM process to gradually deploy masses. The final envisioned system is expected to have positional stability within the tolerance range of a few μm. The system performance is verified through the use of simulations (ANSYS Maxwell) and experimental analyses. A novel method of using the ratio of conductivity (σ) of the material to density (ρ) of the material to determine the compatibility of the levitation ability of non-magnetic materials with magnetic levitation application is also formulated. The key advantage of this method is that it does not rely on experimental analyses to determine the levitation ability of materials.

Development and Analysis of a Novel Magnetic Levitation System with a Feedback Controller for Additive Manufacturing Applications

“…The research presented in this article highlights the successful development of two novel levitation systems with a significant improvement in performance compared to the prototype previously developed by the authors in [17]. The newly developed systems saw a 77% increase in levitation height (from 4.5 mm in [17] to 8 mm in this article), a 476% increase in the surface area for powder deposition activities (from 1963 mm 2 in [17] to 11,309 m 2 in this article), and assuming a powder deposition rate of 1 g/min, at least a 346% increase in time available for AM operations (from 15.2 min in [17] to 67 min in this article) by having the ability to support 340% additional mass (from 15.2 g in [17] to 66.74 g in this article) within the limits of allowable inputs. The improvement in the performance of the newly developed levitation systems highlights the significant enhancement for performance with AM operations, therefore highlighting the contributions of this article.…”

“…We subsequently developed a novel levitation system with the prime point of emphasis being placed on compatibility with AM operations. The levitation experiment was deemed a success and the initial viability with AM operation was verified [17]. The performance of the levitation system developed, while satisfactory, had significant potential for improvement.…”

“…The working principle has been described in our previous work [16,17]. It is discussed here as well.…”

“…The overall structure of the levitation system remains unchanged from the first iteration of the prototype developed [17]. The levitation system is made up of two currentcarrying coils that carry current in opposite directions.…”

Editorial for the Special Issue on Flexible Micromanipulators and Micromanipulation

“…Kazemzadeh Heris et al [ 1 ] present the design and fabrication of a magnetic actuator for torque and force control using an artificial neural network (ANN)/simulated annealing (SA) algorithm. Kumar et al [ 2 ] propose an electromagnetic micromanipulator levitation system for metal additive manufacturing applications. These two papers demonstrate the potential of magnetic and electromagnetic actuation for micromanipulation and their application in various fields, including additive manufacturing.…”