3D Printed Reversible Shape Changing Components with Stimuli Responsive Materials.
The creation of reversibly-actuating components that alter their shapes in a controllable manner in response to environmental stimuli is a grand challenge in active materials, structures, and robotics. Here we demonstrate a new reversible shape-changing component design concept enabled by 3D printing two stimuli responsive polymers-shape memory polymers and hydrogels-in prescribed 3D architectures. This approach uses the swelling of a hydrogel as the driving force for the shape change, and the temperature-dependent modulus of a shape memory polymer to regulate the time of such shape change. Controlling the temperature and aqueous environment allows switching between two stable configurations - the structures are relatively stiff and can carry load in each - without any mechanical loading and unloading. Specific shape changing scenarios, e.g., based on bending, or twisting in prescribed directions, are enabled via the controlled interplay between the active materials and the 3D printed architectures. The physical phenomena are complex and nonintuitive, and so to help understand the interplay of geometric, material, and environmental stimuli parameters we develop 3D nonlinear finite element models. Finally, we create several 2D and 3D shape changing components that demonstrate the role of key parameters and illustrate the broad application potential of the proposed approach.
The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Yiqi
Y
Mao
Singapore University of Technology and Design, Singapore 138682, Singapore.
Zhen
Z
Ding
State Key Lab for Strength and Vibration of Mechanical Structures, School of Aerospace Science, Xian Jiaotong University, Xian 710049, China.
Chao
C
Yuan
Department of Mechanics, School of Civil Engineering, Beijing JiaoTong University, Beijing, 100044, China.
Shigang
S
Ai
The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Michael
M
Isakov
The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Jiangtao
J
Wu
State Key Lab for Strength and Vibration of Mechanical Structures, School of Aerospace Science, Xian Jiaotong University, Xian 710049, China.
Tiejun
T
Wang
Singapore University of Technology and Design, Singapore 138682, Singapore.
Martin L
ML
Dunn
The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
H Jerry
HJ
Qi