The technique of the lip with cut-out can be used to simulate exactly the shape of the total pressure contour map.

This paper establishes the contour surface equation of a torus CAM and presents a pressure Angle formula, it provides a simple and efficient method for designing this kind of cams.

The impulsive dynamical pressure from frequent blasting has a strong influence on designed tunnel contour, construction error and stability of surrounding rock in the course of excavating tunnel.