Bistable Compliant Mechanism Using Magneto Active Elastomer Actuation

Abstract

In the emerging field of origami engineering, it is important to investigate ways to achieve large deformations to enable significant shape transformations. One way to achieve this is through the use of bistable mechanisms. The goal in this research is to investigate the feasibility and design of a compliant bistable mechanism that is actuated by magneto active elastomer (MAE) material. The MAE material has magnetic particles embedded in the material that are aligned during the curing process. When exposed to an external field, the material deforms to align the embedded particles with the field. We investigate actuation of the MAE material through the development of finite element analysis (FEA) models to predict the magnetic field required to snap the device from its first stable position to its second for various geometries and field strengths. The FEA model also predicts the displacement of the center of the mechanism as it moves from one position to the other to determine if the device is in fact bistable. These results help show the relationship between the substrate properties and the bistability of the device. Experimental results validate the FEA models and demonstrate the functionality of active materials to be used as actuators for such devices and applications of origami engineering.

Actuating Soft Matter with Magnetic Torque

“…Under magnetic fields, the H‐MRE patches experience ferromagnetic torque toward the external magnetic field and cause a mechanical distortion of the surrounding PDMS. Under fields, MAEs work to minimize their magnetic and mechanical energy which can be exploited to, for example, create bistable configurations for dramatic opening and closing of origami structures, (Figure c–d) . These results suggest that sufficient magnetic torque is generated to dramatically overcome the structural stability of these elastomers to produce folding events in multiple positions and along multiple directions under a single magnetic field.…”

“…c) Numerical analysis result of a bistable structure with MAE patches bonded to PDMS. Adapted with permission . Copyright 2015, Sage Publications.…”

Shape-programmable magnetic soft matter

“…hape-programmable matter refers to active materials that can be controlled by heat (1)(2)(3)(4)(5), light (6,7), chemicals (8)(9)(10)(11)(12)(13), pressure (14,15), electric fields (16,17), or magnetic fields (18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33) to generate desired folding or bending. As these materials can reshape their geometries to achieve desired time-varying shapes, they have the potential to create mechanical functionalities beyond those of traditional machines (1,15).…”

“…As a result, such heuristic and unsystematic methods can only program these materials for a limited number of applications, demonstrating only either simple deformations (21,(24)(25)(26)(27)(28) or very specific functionalities (18-20, 22, 23, 29-33).…”

Design, Fabrication, and Modeling of an Electric–Magnetic Self-Folding Sheet

“…Self-folding origami has been the subject of considerable research recently, resulting in many novel applications and actuation approaches [1][2][3]. In most cases, a single active material is used to actuate a model with bending or folding that can be permanent [4,5] or reversible [6][7][8][9]. Each active material used has advantages and disadvantages over the others, and properties of many of these materials have been evaluated and compared [10,11].…”