Fig. 4: The autonomous insect-scale soft inchworm crawler.

a Components of the autonomous clawer, which includes an inchworm-like crawling joint, a battery, and a control circuit. b The autonomous insect-scale robot can crawl on different surfaces (PVC plate, glass, wood, stone surfaces) and even in an open-field environment with soil ground. The pictures are superimposed frames from Supplementary Video 7. c The performance analysis of the inchworm crawler robot. (i) The large stride of the crawler robot, reaching 35%. (ii) The roughness of the crawling surfaces in the experiments. (iii) The crawling speeds across different surfaces, under actuation frequencies ranging from 1 to 5 Hz. (iv) The crawling speeds on inclined PVC surfaces with slopes of 5°, 10°, and 15° across various actuation frequencies. d Continuous operation. (i) Sustained time of the autonomous crawler under different actuation frequencies with a single battery. The yellow dots represent the experimental evaluation results, and an inverse proportional relationship is fitted to the plot by the light blue curve. T and f represent the operation time and actuation frequency, respectively. It is worth noting that at the actuation frequency of 0.67 Hz, the crawler can operate for more than one hour. (ii) The recorded temperature rise of the crawling robot under continuous operation across different frequencies. The temperature reaches thermal equilibrium over time, with a slight decrease observed later due to battery voltage drop as power is consumed. Source data for (c) and d are provided as a Source Data file.