Dielectric elastomer actuators (DEAs) are a special class of artificial muscles that have been used to construct animal‐like soft robotic systems. However, compared with state‐of‐the‐art rigid actuators such as piezoelectric bimorphs and electromagnetic motors, most DEAs require higher driving voltages, and their power density and lifetime remain substantially lower. These limitations pose significant challenges for developing agile and powered autonomous soft robots. Here, a low‐voltage, high‐endurance, and power‐dense DEA based on novel multiple‐layering techniques and electrode‐material optimization, is reported. When operated at 400 Hz, the 143 mg DEA generates forces of 0.36 N and displacements of 1.15 mm. This DEA is incorporated into an aerial robot to demonstrate high performance. The robot achieves a high lift‐to‐weight ratio of 3.7, a low hovering voltage of 500 V, and a long lifetime that exceeds 2 million actuation cycles. With 20 s of hovering time, and position and attitude error smaller than 2.5 cm and 2°, respectively, the robot demonstrates the longest and best‐performing flight among existing sub‐gram aerial robots. This important milestone demonstrates that soft robots can outperform their state‐of‐the‐art rigid counterparts, and it provides an important step toward realizing power autonomy in soft robotic flights.

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Significance Soft actuators have advantages over traditional rigid robots in various applications due to their robustness, low mechanical stiffness, and low weight. Thus far, conventional rigid valves are the most common approach to control hydraulic soft actuators. Although soft valves have been designed in various forms, they have not achieved the pressure or flow rate conditions as required by many existing hydraulic actuators. In this paper, we introduce an electrically driven soft valve using dynamic dielectric elastomer actuators (DEAs). These soft valves have a fast response time and are able to control fluidic pressure and flow rates that match the needs of hydraulic actuators with mesoscale channels. The DEA valves enable possibilities for soft onboard controls for future fluidic soft robots.

This work presents multiple methods of creating high aspect ratio fluidic soft actuators that can be formed individually or in large arrays via dip coating. Within this methodology, four strategies are provided to mechanically program the motion of these actuators, including the use of fiber inclusions, gravity, surface tension, and electric fields. The modular nature of this dip coating fabrication technique is inexpensive, easy to modify, and scalable. These techniques are used to demonstrate the fabrication of soft actuators with aspect ratios up to 200:1 and integrated arrays of up to 256 actuators. Furthermore, these methods have the potential to achieve higher aspect ratios and larger array sizes. Operating pressure, curvature, and curling strength tests reveal the design space in which fabrication parameters can be selected to tune the input and output parameters of soft bending actuators. An individual bending actuator made with these methods weighs between 0.15 and 0.5 g, can hold up to 2 N, and can be designed to work in groups to increase curling strength with distributed contact forces. Arrays of these actuators may be useful in atypical grasping and manipulation tasks, fluid manipulation, and locomotion.