I have posted a literate Haskell module "Fuzzy_oscillator"
in our collection of Haskell modules:
http://www.numeric-quest.com/haskell/
You may also download it as a gzipped bundle (containingg 9 plots)
according to downloading instructions on that page.
Credits go to Gary Meehan and Mike Joy from University of warwick
for their module Fuzzy.hs.
Summary
-------
This module presents a short study of one-degree-of-freedom (1DOF)
oscillator subjected to resonant sinusoidal excitation force and
whose vibrations are controlled by a family of fuzzy controllers:
+ Velocity controller
+ Displacement controller
+ Displacement-velocity controller
Haskell simulations demonstrate that each controller performs
extremely well -- reducing resonant amplitudes to comparatively
small values, even though none of the controllers is thoroughly
tuned and our choice of kinematic fuzzy subsets is very
simplistic.
This suggests that fuzzy logic offers very powerful tools to
vibration control engineers; no special skills for solving
nonlinear equations are required and purely experimental approach
would suffice to design good controllers for such applications.
The obvious physical realizations of fuzzy controllers
are active devices that employ sensors, processors
and actuators. Less appreciated is, however, fact that traditional
passive control -- such as dry friction, viscous damping,
nonlinear springs or snubbers -- can be also modeled by fuzzy logic.
Jan
