Right conoid

In geometry, a right conoid is a ruled surface generated by a family of straight lines that all intersect perpendicularly to a fixed straight line, called the axis of the right conoid.

Using a Cartesian coordinate system in three-dimensional space, if we take the z-axis to be the axis of a right conoid, then the right conoid can be represented by the parametric equations:

${\displaystyle x=v\cos u}$

${\displaystyle y=v\sin u}$

${\displaystyle z=h(u)}$

where h(u) is some function for representing the height of the moving line.