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44%和71%。Taking earthworm (Eisenia foetida) as the study object, six surface specimens including motionless, extending and shrinking of the forehead and body were prepared according as its movement characteristic. The soil adhesion force and sliding resistance experiments of earthworm nonsmooth surface specimens and steel specimen were conducted on via a tiny adhesion testing system. The results showed that the shrinking specimen had best reducing soil adhesion force and sliding resistance ability, then were motionless specimen and the extending specimen respectively. The forehead sample had better reducing soil adhesion force and sliding resistance ability than the body sample. In the test condition, the soil adhesion force and sliding resistance of the forehead sample were 25% and 61% of that of the steel specimen respectively. The soil adhesion force and sliding resistance of the body sample were 44% and 71% of that of the steel specimen respectively.  