Spiral needed with a twist

[Anonymous]

Typ., all of the spiral lisp I've found offset the growth ring the same distance, ex. first ring 4m, next 4m , next 4 m, etc.

Can anyone make a slight adjustment to an existing or new lisp/VBA program to add a plus factor number such as 1 to the previous spiral ring? The plus factor number is the twist. Example, if the radius of the first ring intersection point is 4 meters, add plus 1 factor to each subsequent ring making the next ring it 5 meters, next is 6 meters, next is 7 meters, etc.

I need to be able to provide geometric input such as start point and radius of first ring. It would even better if I input my own offset factor. Instead of inputting a plus 1 for each ring, I might try 1.25, 1.50, 1.75 or 2, until I got the shape I wanted. If not, it could be identified in the lisp where I could edit the plus factor number.

I hope my request is clear. Thank you in advance.

[Anonymous]

I had the users run your routines and they plan to do some alternate studies using them. One question I have is within the routine, we are asked for the "Interval Between Turns?". I'm not 100 percent how to answer this question.

[Anonymous]

That's the difference in radius, or spacing, or gap, between the starting
point and the next time the spiral gets around to the same place again
(after one turn or rotation).

In the Equally-spaced spiral, it will be the constant distance between
passes anywhere along the spiral

In the Arithmetically-increasing spiral, it's the "1 factor" in your earlier
description: "if the radius of the first ring intersection point is 4
meters, add plus 1 factor to each subsequent ring making the next ring it 5
meters, next is 7 meters, next is 10 meters, etc", except it doesn't have to
be 1; it can be any size the user wants. In that type, the second interval
(or spacing, or gap) will be twice as big, the third one will be three times
as big, etc.

In the Geometric one, it will increase with each rotation in a different
way, as described in the Lisp text.

Of course, you can change the prompt if you prefer a different wording.
--
Kent Cooper


wrote...
I had the users run your routines and they plan to do some alternate studies
using them. One question I have is within the routine, we are asked for the
"Interval Between Turns?". I'm not 100 percent how to answer this question.

[Anonymous]

That was great information. Once I copied your previous comment and your comments in the lisp routine, the designers totally get it! Thanks again. I'm sure others will make use of this routine.