A multi-stimuli-responsive actuator for efficient thermal management and various biomimetic locomotion

Abstract

Creating flexible actuators that mimic natural organisms' movements and respond to various stimuli is highly significant for bionic soft robotics, electronics, and wearables. However, achieving a simultaneous response to multiple stimuli within a single actuator still has great challenges in terms of structural design. Here, by combining carbon nanotubes with high photothermal effect, bacterial cellulose with water-triggered expansion, and polyethylene with a large thermal expansion coefficient, a bilayer actuator is proposed with macroscopic and fast response to natural sunlight, low voltage, temperature, humidity, and organic solvents. Based on this, we propose a smart curtain that passively responds to light changes, lowering room temperature by 10.9°C to reduce the huge energy consumption for thermal management of buildings. Besides, a multi-stimulus response curtain that switches according to ambient humidity is designed. Interestingly, this soft actuator can also realize complex bionic motions such as bionic clamping, jumping, self-oscillation, and crawling.