A surface is a kind of geometric figure, which is the trajectory of a moving straight line (straight line or curve) moving continuously in space. The straight line (straight line or curve) that produces the surface is called a generatrix. The line or surface that controls the bus movement is called conductor or guide surface, and any position of the bus on this surface is called plain line. Curve AB is a conductor, straight line SB is a bus, and every position where SB moves is a prime line.
The center of the curved surface formed when the generatrix is a straight line is called ruled surface; The surface formed when a bus is bent is called a surface. The surface formed when the bus moves regularly is called a regular surface. The points, lines and surfaces that control the bus movement are called fixed points, lines and guide surfaces.
Extended data
Calculation formula of straight cone bus
L represents the generatrix of the cone, h represents the height of the cone, and r represents the radius of the bottom surface of the cone.
Then according to Pythagorean theorem,
So,
This is the calculation formula of conical bus.
Derivation of Calculation Formula for Cone Bus
Using the calculation formula of conical bus,