Abstract: Magnetically driven constitutes one of the significant drive modalities for small soft robots.Currently,the majority of magnetically driven soft robots employ external magnetic fields and exhibit weak crawling capabilities. To address this problem,a worm-like soft robot with built-in electromagnetically driven was proposed, which can crawl on sloping surfaces with multiple angles. Two models of soft-bodied robots,sized at 20 mm×6 mm×11 mm and 22 mm×6 mm×11 mm,were utilized in the experiments to verify the effect of the strength magnitude of the attracting and repelling magnets of the copper coils on the stability of crawling. It was concluded that the soft robot with a larger intermediate distance possesses stronger crawling stability and crawling ability,and it can crawl at a speed exceeding 1 mm/s on a maximum slope of 40°;the soft robots with small intermediate distances crawl faster,but have less crawling ability and stability. The influencing factors of the maximum slope and the motion action principle of the soft robot were presented, the thickness of the silicone,the selection of the drive device and the motion analysis of the electromagnetic contacts were discussed,and a variety of slope angle crawling experiments under the environment of no external magnetic field were carried out.

Key words: soft robot, inchworm, electromagnet, copper coil