Tunable, Flexible, and Resilient Robots Driven by an Electrostatic Actuator

Abstract

Robustness, deformability, maneuverability, and ease of fabrication are among the most desirable features of soft robots that can adapt to various working environments and complex terrains. Herein, polymeric thin‐film‐based flexible robots are designed, prototyped, and examined that use mechanical instability and electrostatic force actuation for locomotion. An electrostatic actuator is first developed using a buckled beam that can deform by up to 68% of its height under an applied voltage. A centimeter‐scale robotic bug is then designed that shows superb flexibility, adaptability, and maneuverability by incorporating origami structural elements. For instance, the robotic bug can be completely smashed and still recover its mobility, walk on various terrains, slopes (up to 30°) and narrow spaces, overcome hurdles, make turns, and even move backward with a crawling (linear) and turning (rotation) speed up to 40 mm s−1 and ≈45° s−1, respectively. Such remarkable characteristics are controlled by a set of parameters such as the amplitude and frequency of the input voltage and/or the origami geometries. The facile and tunable design and the actuation principle can potentially enable ample opportunities for the development of the next‐generation soft robotics.

Low‐Voltage Soft Actuators for Interactive Human–Machine Interfaces

“…A direct way to lower the operational voltage of electrostatic actuators is through the reduction of the thickness of the film coated with electrodes. [296,297] By doing so, the bending rigidity of the film that resists against the electrostatic forces is reduced. Demonstrated with an electrostatic actuator with two films separated by an arch-shaped gap, changing the thickness from 127 to 25 μm minimized the activating voltage from 700 to 200 V. [296] Similarly, Hartmann et al designed a soft subkilovolt tuneable lens based on electrostatic zipping.…”

“…[296,297] By doing so, the bending rigidity of the film that resists against the electrostatic forces is reduced. Demonstrated with an electrostatic actuator with two films separated by an arch-shaped gap, changing the thickness from 127 to 25 μm minimized the activating voltage from 700 to 200 V. [296] Similarly, Hartmann et al designed a soft subkilovolt tuneable lens based on electrostatic zipping. [297] This was achieved through adhering to theoretical models developed which comprised tuning actuator design parameters including the dielectric constant and thickness of the plastic foil coated with electrodes along with the opening angle.…”

Slider Sheet Detection in Charge-Induction Electrostatic Film Actuators

“…In the field of robotics, many studies have utilized electrostatic force for adhesion to walls, in the form of electro-adhesion devices [ 6 , 7 , 8 , 9 ]. In other robotic applications, electrostatic actuators show promise as powerful and flexible artificial muscles for robots [ 10 , 11 , 12 , 13 , 14 ].…”

Analytical displacement-controlled solutions to bifurcation buckling and post-buckling of soft functional beams with constrained ends

“…"Everyone loves a buckling problem", as stated by John Hutchinson and Bernie Budiansky in 1979 (Hutchinson and Thompson, 2018), the elastic buckling problems of slender structures, thin plates and shells are charming topics in structure mechanics with a very long history. Focusing on the static Euler buckling of the elastic slender structures, it has recently been adopted as an important deformation strategy for stretchable electronics (Su et al, 2012;Xu et al, 2015;Zhao et al, 2021) and many other interesting modern devices, such as the actuators of soft robotics (Aimmanee and Tichakorn, 2018;Chen et al, 2019;Jin et al, 2020), tunable mechanical resonators (Hajjaj et al, 2021;Qiu et al, 2021;Zhang et al, 2017) and sensors (Alcheikh et al, 2021a;El Mansouri et al, 2019), and shock absorbers (Deng et al, 2020;Frenzel et al, 2016;Shan et al, 2015). As shown in Fig.…”