The electro-thermal actuators (ETA) are smart devices that can convert electric energy into mechanical energy under electro-heating stimulation, showing great potential in the fields of soft robotics, artificial muscle and aerospace component. In this study, to build a low-voltage activating, fast responding ETA, a robust and flexible carbon nanotube film (CNTF) with excellent electrical and thermal conductivity was adopted as the conductive material. Then, an asymmetric bilayer structured ETA was manufactured by coating a thin layer of polydimethylsiloxane (PDMS) with high coefficient of thermal expansion (9.3 × 10^–4 °C⁻¹), low young’s modulus (2.07 MPa) on a thin CNTF (~ 11 μm). The as-produced CNTF/PDMS composite ETA exhibited a large deformation (bending angle ~ 324°) and high electro heating performance (351 °C) at a low driving voltage of 8 V within ~ 12 s. The actuated movement and the generated heat could be controlled by adjusting the driving voltages and showed almost the same values in 20 cycles. Furthermore, the influences of the PDMS thickness and driving voltage on CNTF/PDMS composite ETA performance were systematically investigated. The CNTF/PDMS soft robotic hand which can lift 5.1 times and crab 1.3 times of its weight demonstrated its potential capability.

电热致动器（ETA）是可以在电热刺激下将电能转换为机械能的智能设备，在软机器人，人造肌肉和航空航天领域具有巨大的潜力。在本研究中，为了构建低压激活，快速响应的ETA，采用具有优异电导率和导热率的坚固而灵活的碳纳米管薄膜（CNTF）作为导电材料。然后，通过涂覆具有高热膨胀系数（9.3×10 ^–4  °C ^-1的聚二甲基硅氧烷（PDMS）薄层）来制造不对称双层结构的ETA），薄CNTF（〜11μm）上的低杨氏模量（2.07 MPa）。所生产的CNTF / PDMS复合材料ETA在〜12 s内以8 V的低驱动电压表现出较大的变形（弯曲角度〜324°）和较高的电加热性能（351°C）。可以通过调节驱动电压来控制致动运动和产生的热量，并且在20个循环中显示出几乎相同的值。此外，系统研究了PDMS厚度和驱动电压对CNTF / PDMS复合ETA性能的影响。CNTF / PDMS软机器人手可以举起其重量的5.1倍，而螃蟹可以举起其重量的1.3倍，证明了其潜在的功能。