Bionic structure robot find it’s way in pipelines
A Soft Robot Driven by a Spring-Rolling Dielectric Elastomer Actuator with Two Bristles
Confined space searches such as pipeline inspections are widely demanded in various scenarios, where lightweight soft robots with inherent compliance to adapt to unstructured environments exhibit good potential. Researchers from Universities in China created a tubular soft robot with a simple structure of a spring-rolled dielectric elastomer (SRDE) and compliant passive bristles – their report is published on www.mdpi.com
Due to the compliance of the bristles, the proposed robots can work in pipelines with inner diameters both larger and smaller than the one of the bristles. Firstly, they investigated the nonlinear dynamic behaviours of the SRDE. Then they fabricated the proposed robot with a bristle diameter of 19 mm and then studied its performance in pipelines on the ground with inner diameters of 18 mm and 20 mm.
Similar to the motion mechanisms adopted by most soft robots, the robots driven by dielectric elastomers (DEs) mainly achieve directional motion through an anchoring structure, such as electrostatic adsorption and mechanical anchoring, anisotropic structure (e.g., bristles), or legged motion structure. However, most of the current dielectric elastomer robots (DERs) tends to work in a single environment; for example, some robots can only crawl on the ground, while a robot with two complex anchors can only adapt to pipelines whose inner diameter is less than the anchors external contour. To solve this problem, inspired by the driving principle of bristle robots, the researchers designed a crawling robot driven by SRDE with wide adaptability.
(a) Schematic diagram of the crawling robot. (b) The physical crawling robot.
It can not only crawl in pipelines with an inner diameter larger than the external contour of bristle, especially on the ground horizontally (faster than two body lengths per second), but also move in pipelines with an inner diameter smaller than the external diameter of bristle in a creeping motion horizontally (close to two body lengths per second) and vertically (close to one body length per second). In addition, this bristle has a simple design and an easy fabrication process. Hence, it exhibits high application adaptability in a variety of environments.
The driving principle of the SRDE (a–c) and the crawling law of the robot (d,e). (a) The schematic diagram of the SRDE with no voltage. (b) The schematic diagram of the SRDE under high voltage. (c) The force analysis of SRDE. (d) The external force of the robot from contraction to elongation. (e) The external force of the robot from elongation to contraction. (f) The position of the robot after one period.
The research was carried out by School of Mechanical and Electrical Engineering, Xi’an University of Architecture and Technology, Xi’an 710049, China and Research Centre for Medical Robotics and Minimally Invasive Surgical Devices, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences, Shenzhen 518055, China
Funding
This research was fund by the National Natural Science Foundation of China under Grant 52105038, the Shenzhen Science and Technology Program under Grant JSGG20201103094400002, the Shenzhen Fundamental Research Project under Grant JCYJ20200109115639654.
Full details on the research can be found at https://www.mdpi.com/2072-666X/14/3/618
