“…This paper aims to systematically review the state-of-art actuation mechanisms for flexible and stretchable microdevices. We first elaborate on the fundamental working principle of different actuation mechanisms based on power sources of pneumatic, 41 hydraulic, 36 thermal, 42 electrical, 43 magnetic, 44 humidity, 45 chemical, 46 mechanical, 47 etc. The structure designs, characteristics, and performance of various actuators are discussed and compared.…”