Soft actuators have numerous applications in soft robotics due to their capability of mimicking quite complex motions observed in living things with deformable organs. In the present research, a programmable, low-cost soft actuator based on phase-change material (PCM) composites is developed, using silicon rubber as the matrix, ethanol as the phase-change fluid, and carbon fabric as the conductive path which generates the required heat for actuation. The required pressure for actuation is provided by the electrically-induced phase transition of the PCM (30W electrical power supply). FESEM images illustrate the homogenous distribution of ethanol microbubbles within the active area, with an average diameter of 14.66μm, and their absence inside the passive layer. The temperature is monitored by an internal thermal sensor placed inside the composite, and controlled to prevent overheating (T > 80 °C) in the active area. The gripper fabricated by using this composite produces considerable motion using a low-voltage driving force (∼30 V). Moreover, it undergoes a sizeable displacement (∼9 cm) and bending angle (∼50°), considering the low amount of power input (30W). Additionally, the tip of the gripper reaches the maximum velocity of ∼1 mm s−1, and the designed sample is capable of lifting objects with varying shapes and weights (from ∼10g to ∼300g).

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