Ultra‐Fast Shape‐Deformation and Highly‐Sensitive Detection of 4D Printed Electromagnetic Architectures

Abstract 4D printing is widely used in soft actuators, flexible electronic devices, and soft robotics. However, existing 4D printed architectures suffer from drawbacks such as long shape‐deformation response time or low sensitivity to external stimuli, which greatly limit their applications. To address these shortcomings, 4D printed electromagnetic architectures (EMAs) with both ultra‐fast shape‐deformation and highly‐sensitive detection capabilities have been proposed in this study. The EMA is composed of a 4D printed polymeric scaffold, along with magnetic and conductive parts. Experiments show that the EMA exhibits not only an ultra‐fast shape‐deformation response time as low as 0.007 s but also a high sensitivity to detect an external pressure down to 0.4 Pa, which is beyond records of all current 4D printing reports. Numerical simulation reveals the rapid shape‐deformation and sensing mechanism of EMAs. The effects of cell structures on the performances of EMAs are investigated by parameter optimization. Finally, a “sensing‐to‐deforming” system has been demonstrated, which can smartly distinguish objects by pressures and then trap or release them by the shape deformation. This work realized the effective coupling of ultra‐rapid shape‐deformation and ultra‐low stress sensing of 4D printed architectures and provided an effective method for integrated development of smart devices in deformation and sensing.