Bio‐Mimic, Fast‐Moving, and Flippable Soft Piezoelectric Robots

Abstract

Cheetahs achieve high‐speed movement and unique athletic gaits through the contraction and expansion of their limbs during the gallop. However, few soft robots can mimic their gaits and achieve the same speed of movement. Inspired by the motion gait of cheetahs, here the resonance of double spiral structure for amplified motion performance and environmental adaptability in a soft‐bodied hopping micro‐robot is exploited. The 0.058 g, 10 mm long tethered soft robot is capable of achieving a maximum motion speed of 42.8 body lengths per second (BL/s) and a maximum average turning speed of 482° s−1. In addition, this robot can maintain high speed movement even after flipping. The soft robot's ability to move over complex terrain, climb hills, and carry heavy loads as well as temperature sensors is demonstrated. This research opens a new structural design for soft robots: a double spiral configuration that efficiently translates the deformation of soft actuators into swift motion of the robot with high environmental adaptability.

Multidirectional Planar Motion Transmission on a Single‐Motor Actuated Robot via Microscopic Galumphing

“…Within the realm of small-scale planar crawlers, the key performance metrics include mass, speed, and power source, as depicted in Figure 5I. [1][2][3][4][5][6][7][8][10][11][12][13]17,19, Soft-crawling robots are predominantly externally powered and can weigh as little as 0.9 g. [19] Conversely, many rigid crawling robots utilize battery power and can weigh as little as 1.7 g. [2] The GASR possesses a light weight of 1.2 g and an average speed of 1.1 BL s −1 , nearly rivaling externally powered robots. Furthermore, robots employing unstable galumphing and vibration-based slipping are located within the red and blue regions of the performance space, respectively.…”

“…When the output force F of the motor is sufficiently large to elevate the robot in air, it can galumph. Unlike previous soft robots that galumph unstably, [12,13] GASR can perform regular and predictable galumphing. As depicted in Figure 6D, four phases of motion are involved in a complete galumphing cycle: both-touching, A-touching, B-touching, and aerial.…”

“…Recent developments have demonstrated that robots utilize galumphing for forward movement. Piezoelectric soft robots [12,13] accomplish rapid galumphing (≈200 Hz) but suffer from motion instability owing to their flexible structures. Conversely, hopping robots, [14][15][16] actuated by servomotors, can achieve stable and efficient galumphing at lower frequencies (<50 Hz).…”

Advancements in Soft Robotics: A Comprehensive Review on Actuation Methods, Materials, and Applications

“…( e ) Schematic of electrochromic principle and the disguise process by applied DC voltage; Reprinted with permission from the study presented in [ 49 ], License Number: 5760770707891, Copyright 2022 Wiley-VCH GmbH. ( f ) BFFSPR climbs a 12° slope and moves after falling and flipping from a high platform [ 50 ].…”

“…Vibration is a fast motion often observed in nature (like honeybees) and our daily lives (e.g., strings). Therefore, soft robots worked by vibration have attracted the attention of researchers due to their outstanding response time and output forces [ 50 ]. For example, Chen et al [ 50 ] reported a bionic piezoelectrical soft robot made of inverse piezoelectric-actuated PVDF film, Ag electrodes, and a passive layer film(Cu).…”