Origami-Inspired Soft Actuators for Stimulus Perception and Crawling Robot Applications

Origami has been proved as a valuable tool to develop deployable, multifunctional, and tunable devices for diverse engineering applications. Inspired by the Kresling origami, this article presents a soft pneumatic actuator with vacuum control to realize the compound motion of twist and contraction. The twist direction varies as the crease angle changes and it offers pure contraction after combining two actuators with reverse creases. Our actuator can lift 180 folds of its weight and achieve the contraction ratio of 47%, while the response time is below 0.3 s. The origami-based actuator can realize an adjustable bistable property, leading to the possibility for external stimulus detection and mechanical memory devices, where the sensitivity can be regulated by the initial vacuum pressure. Through several actuators, we demonstrate the reconfigurable crawling robots capable of worm-like creep, alternating-step locomotion as well as obstacle detection. After activating all the actuators, the four-actuator robot with two working modes is validated to perform agilely for confined space navigation, showing our actuator has the potential in soft robotics applications.