First, this paper introduces three basic worms propagation models and analyzes four situations after the introduction of benign worm.

This paper presents a calculating method for the edge of a new hob with straight groove and zero rake Angle. The original section edge of the said hob is on the surface of basic worm.

It will help researchers learn how basic neural circuits work together in sensing and responding to the environment, such as when a worm smells food and crawls toward it.