Magnetic-Field-Assisted Projection Stereolithography for Three-Dimensional Printing of Smart Structures

Abstract

In this paper, an additive manufacturing (AM) process, magnetic field-assisted projection stereolithography (M-PSL), is developed for 3D printing of three-dimensional (3D) smart polymer composites. The 3D-printed magnetic field-responsive smart polymer composite creates a wide range of motions, opening up possibilities for various new applications, like sensing and actuation in soft robotics, biomedical devices, and autonomous systems. In the proposed M-PSL process, a certain amount of nano- or microsized ferromagnetic particles is deposited in liquid polymer by using a programmable microdeposition nozzle. An external magnetic field is applied to direct the magnetic particles to the desired position and to form the desired orientation and patterns. After that, a digital mask image is used to cure particles in photopolymer with desired distribution patterns. The magnetic-field-assisted projection stereolithography (M-PSL) manufacturing process planning, testbed, and materials are discussed. Three test cases, an impeller, a two-wheel roller, and a flexible film, were performed to verify and validate the feasibility and effectiveness of the proposed process. They were successfully fabricated and remote controls of the printed samples were demonstrated, showing the capability of printed smart polymer composites on performing desired functions.

A Fully Three-Dimensional Printed Inchworm-Inspired Soft Robot with Magnetic Actuation

“…The appropriate layer thickness and curing time were selected based on our previous study of the relationship between the curing depth and the magnetic particle loading fraction. 44 The volume loading fraction of the magnetic particles in the two legs was 37.34%.…”

Air-Diffusion-Channel Constrained Surface Based Stereolithography for Three-Dimensional Printing of Objects With Wide Solid Cross Sections

“…The ultraviolet (UV) light penetrates the transparent constrained surface and cures the liquid polymer. Currently, the two most widely used classes of constrained surfaces are: (1) glass or acrylic plate coated with polydimethylsiloxane (PDMS) [8,[12][13][14][15][16][17][18] and (2) air permeable film that is clamped and tensioned, due to the relatively low cost, ease of fabrication, good oxygen permeability, and excellent optical transparency. The oxygen permeability of constrained surface is critical to the reliability and robustness of the system, and the printable geometries [19].…”

Correlation Between Microscale Magnetic Particle Distribution and Magnetic-Field-Responsive Performance of Three-Dimensional Printed Composites

“…By combining various materials that serve mechanical, electrical, chemical, thermal, and/or optical functions with controlled distributions at microscale in the polymer matrix, smart particlepolymer composite with multiple functionalities can be fabricated [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Transformative applications have been demonstrated in targeted drug delivery, micromachines, microelectromechanical systems, by using the advanced characteristics of such particlepolymer composite [3][4][5][6][7][8][9][10][11][12][13].…”

“…By combining various materials that serve mechanical, electrical, chemical, thermal, and/or optical functions with controlled distributions at microscale in the polymer matrix, smart particlepolymer composite with multiple functionalities can be fabricated [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Transformative applications have been demonstrated in targeted drug delivery, micromachines, microelectromechanical systems, by using the advanced characteristics of such particlepolymer composite [3][4][5][6][7][8][9][10][11][12][13]. Four examples of the smart composite applications are: (a) a self-folding microgripper, which consists of flexible polymer hinges and rigid Au/Ni phalanges, for collecting tissue samples from porcine liver [3]; (b) a soft reconfigurable connector fabricated by filling magnetically oriented platelets in the soft polymer, which changes shape under an external magnetic field [5]; (c) a microfish, which has iron oxide and platinum nanoparticles embedded in the polymer matrix at different regions, for targeted drug delivery and toxin-neutralization applications [4]; (d) a mesoscale turbo fan, which has iron particles embedded on its blade tips and can rotate with various rotation speeds under an external magnetic field [9].…”

“…In this process, both the magnetic platelet loading fraction and orientation can be controlled in a layer-bylayer way. In our previous study, we developed a new additive manufacturing process, magnetic-field-assisted projection stereolithography (M-PSL), and demonstrated its capability of fabricating particle-polymer composites with various particle distributions and product properties [9]. In the developed M-PSL process, magnetic particles can be filled into the polymer matrix with different orientations, structured chains, and loading fractions to achieve varied composite properties and product functionalities.…”