Please be patient while the applet is loaded (93K)...
Drag with the mouse in the graph window to rotate the object.
The values in the "Controls" window affect the shape of the surface. The values of a and b control the radius of the cone, which is given by the function r(t) at the bottom of the panel. The value of c determines the width of the small tube that runs along the center of the cone. The function f(t) gives the shape of the central curve; changing this will let you make a dimensional object that is uniquely yours! The Domain value gives the lower and upper limits of t to be plugged into f.
You may use the "Graphics" menu of the graph window to control some of the visual characteristics of your image. For example, you can thicken the lines, or make the surface be filled in (rather than outlined). Use the "Control" menuof the graph window to zoom out if the surface is too large to fit entirely in the window.
When you are done with the demonstration, choose the "Exit Demo" menu item from the "Windows" menu of the "Controls" window. The applet will not exit until you do so.