Untethered Flight of a 270 mg Microrobot Powered by Onboard Energy

Abstract

It is challenging for microrobots to fly using onboard energy due to the relatively heavy power supplies and inefficient actuators that are limited to a small size (mass less than 1000 mg and wingspan less than 100 mm). Inspired by the movement of jellyfish in nature (Physophora hydrostatica), herein, a microscale aerial vehicle FlyJelly is introduced, powered by onboard energy to achieve untethered flight. FlyJelly uses a balloon filled with helium to overcome self‐gravity and an actuator powered by electrostatic power to generate thrust. The balloon, heat sealed with two gold‐covered Mylar films, weighs 95.56 mg, provides 257.9 mg of buoyancy when filled with helium, and stores 19.457 × 10−3 J of energy when powered by 2400 V of direct current. The electrostatic actuator is composed of multiflapping units arranged radially and symmetrically, consuming only 0.3370 mW of power but generating a thrust of 0.2271 mN to drive the vehicle for flight. Benefiting from a design of distributed propulsion, FlyJelly is highly reliable and continues to work well even after the actuator is damaged. The milligram‐level weight, untethered flight with onboard energy, and high reliability make the prototype suitable for development as a long‐term remote exploration and search‐and‐rescue mission.

A novel electric stimulus-responsive micro-actuator for powerful biomimetic motions

“…Furthermore, the actuator has an output power density of 54.71 W kg −1 due to the quality of the milligram level. The proposed actuator is more powerful than electrostatic actuators, 4 and the energy efficiency matches or even exceeds those of the PZT actuator, the DEA actuator and natural muscle. 12,40 A millimetre-sized crawling robot driven by the micro-actuator As illustrated in Fig.…”

“…These rigid actuators possess high resonant frequencies, large deflection, and significant reaction forces. Piezoelectric actuators, 25 magnetic actuators, 26 and electrostatic actuators 4 are some typical examples of rigid actuators that have shown great ability in the motions of crawling, [27][28][29][30] jumping, 5,[31][32][33] and flying. [34][35][36] However, these actuators are typically limited to centimetre-sized robots, as achieving high energy efficiency with favourable physical scaling becomes a significant challenge as the size of the actuators decreases.…”

“…Small creatures in nature have powerful crawling, jumping, or flying mobility, which is affected by the reaction between predator and prey. 1,2 Animal locomotion may provide biologically relevant insight into robot motion, [3][4][5] such as grabbing, [6][7][8] crawling, 9,10 and jumping. 1 In bio-inspired robotics, soft actuators play an important role due to their ability to handle deformable and fragile objects and adapt to irregular shapes.…”