[PD] Rotating object rolling on irregular terrain

Andy Farnell padawan12 at obiwannabe.co.uk
Fri Mar 7 09:23:38 CET 2008


I'm trying to obtain a waveform for a rolling cylinder on an irregular
surface. The signature looks like the attached, or see this paper.

https://www.enactivenetwork.org/download.php?id=97

Rath gives a formula that uses a square root, which I want to avoid.

Several methods I've tried, based on samplehold and a parabolic
shaper almost get there, but I can't quite crack this one.

It is the circular motion of the cylinder rotating around the last
maxima and truncated by the intersection of the radius with the next
minima.

I want to generate it from a samplehold noise (step waveform) source
in real time, so no look ahead or tables (although delaying by
some blocks is okay)

I've tried integrating and shaping the step wave, but it's not right :(

Now I can't see the wood for the trees and think I'm missing something
really obvious. 

Any geometry experts got an idea? 

Preferably something only in the signal domain.

Cheers,

Andy


-- 
Use the source
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