From fundamentals to future challenges for flexible piezoelectric actuators

Flexible actuators, as the main components of soft robots and intelligent structures, can produce reversible mechanical deformations in response to external environmental stimuli such as light, electric fields, steam, and more. Piezoelectric flexible actuators, in particular, demonstrate clear advantages compared to other types of actuators due to their high precision, extremely fast response speed, low power consumption, and lack of magnetic interference and noise. As a result, they are being developed for high-end application areas such as aerospace, wearable devices, and biomedicine. This review first introduces the concept and performance parameters of flexible piezoelectric actuators. It then systematically reviews research achievements and progress on flexible piezoelectric actuators in terms of materials, structures, and fabrication processes. Finally, it analyzes existing problems, puts forward some research suggestions, and outlines prospects for future development.