Multimodal Self-Folding of Shape Memory Polymer Using Laser Induced Graphene

Author

Liam Harrison Drew, Cal PolyFollow

Available at: https://digitalcommons.calpoly.edu/theses/3123

Date of Award

6-2025

Degree Name

MS in Mechanical Engineering

Department/Program

Mechanical Engineering

College

College of Engineering

Advisor

Leily Majidi

Advisor Department

Mechanical Engineering

Advisor College

College of Engineering

Abstract

Shape memory polymers (SMPs) can undergo programmed shape transformations when heated above their glass transition temperature (T_g), enabling actuation through stimuli such as infrared (IR) radiation and Joule heating. These materials are promising for deployable systems and soft robotics due to their lightweight structure and elimination of traditional mechanical components. While IR-based actuation is simple and low-cost, it lacks precision in uncontrolled environments. Joule heating offers improved control but is often limited by conductive ink properties such as thickness, stiffness, or poor adhesion. This work introduces a novel method for multimodal SMP actuation using laser-induced graphene (LIG) transferred from polyimide to polystyrene (PS)-based substrates. The resulting conductive patterns enable both IR absorption and resistive heating, providing a reliable and scalable approach to SMP activation. An experimental study was performed to investigate the self-folding performance of the SMP sample using LIG patterns under IR and Joule Heating. The heat transfer process through the SMP substrate was also studied for IR heating using numerical analysis in MATLAB to support experimental findings.