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thegrumpys / odop

Open Design Optimization Platform (ODOP) - Coil spring design app; mechanical springs; compression spring, extension spring, torsion spring
https://www.springdesignsoftware.org
MIT License
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Objective function scaling improvements #735

Open grumpyinca opened 2 years ago

grumpyinca commented 2 years ago

The current approach to blending various contributions to the objective function (evaluates to the Objective Value) involves model variables smin, smax & sdlim and middleware functions setSclDen.js & sclden.js. It is possible that limitations of this approach have a role in creating "pathological cases" where Pattern Search converges (delmin) to a solution that is significantly inferior to a solution that is known to be available and reachable from a (perhaps only slightly) different starting point. Issue #730 and the v4.3rc2 version of the search at script tutor8 p3 illustrate one such case.

The discussion in #730 has included the ideas of:

These and other approaches to improve objective function scaling should be investigated as part of resolving this issue.

grumpyinca commented 2 years ago

Pending discussion: Replace Cycle_Life with Cycle_Life_Exponent.