The concealed intelligent switch based on 4D printed shape-memory polymers

Concealed intelligent switches have significant potential for use in security and encryption applications. Recently, several four-dimensional (4D) printed intelligent devices have been designed and fabricated using 3D printing technologies and intelligent materials. These devices have demonstrated stupendous capabilities in smart switches and actuators. In this study, a concealable smart switch that combines a double spiral structure and smart materials is proposed. To achieve the desired performances, the fixity ratio is optimized to values more than 88% by comparing selected structures printed with common shape-memory materials. Furthermore, applications for non-contact circumstances without any control electric circuits (for example, hidden water valves) are also proposed. Results demonstrate that the outputs of the intelligent switches are related to their different input conditions, and the implementation rules can be further used as black box rules for security and encryption applications. Thus, intelligent devices manufactured using 4D printed shape-memory polymers can be applied in various fields such as in intelligent actuators and soft robots.