a"Earthworm" is the common name for the largest members of Oligochaeta (which is either a class or subclass depending on the author) in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores...
This design transforms the piston ring’s cross-section into a groove structure similar to that on the earthworm’s surface [41,42]. 2. Materials and Methods 2.1. Design of Bionic Piston Ring The wavy, non-smooth structures that are characteristic features of earthworms endow them with ...