Modeling and validation of a compliant bistable mechanism actuated by magneto active elastomers

Open Access
Author:
Crivaro, Adrienne Marie
Graduate Program:
Mechanical Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
July 14, 2014
Committee Members:
  • Mary I Frecker, Thesis Advisor
  • Timothy William Simpson, Thesis Advisor
Keywords:
  • origami
  • active material
  • bistable mechanism
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. First, the actuation of the MAE material through finite element analysis (FEA) models was investigated. This helps 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 are validated using experimental models and demonstrate the functionality of active materials to be used as actuators for such devices and applications of origami engineering. Next, parametric studies using the FEA model are performed to visualize the tradeoffs between various design parameters. These results help show the relationship between the substrate properties and the bistability of the device. With this information, it is possible to select design parameters based on the desired arch displacement or allowable field strength for a specific task.