LS-OPT®
In the "conventional design" approach, a design is improved by
evaluating its "response" and making design changes based on experience
or intuition. This approach does not always lead to the desired result,
that of a ‘best’ design, since the design objectives are often in
conflict. It is therefore not always clear how to change the design to
achieve the best compromise of these objectives. A systematic approach
can be obtained by using an inverse process of first specifying the
criteria and then computing the ‘best’ design according to a
formulation. The improvement procedure that incorporates design criteria
into a mathematical framework is referred to as Design Optimization This
procedure is often iterative in nature and therefore requires multiple
simulations.
No two products of the same design will be identical in performance, nor
will a product perform exactly as designed or analyzed. A design is
typically subjected to Structural variation and Environmental variation
input variations that cause a variation in its response that may lead to
undesirable behavior or failure. In this case a Probabilistic Analysis,
using multiple simulations, is required to assess the effect of the
input variation on the response variation and to determine the
probability of failure.
To run and control multiple analyses simultaneously, LS-OPT provides a
simulation environment that allows distribution of simulation jobs
across multiple processors or networked computers. Each job running in
parallel consists of the simulation, data extraction and disk cleanup.
Measurements of time remaining or performance criteria such as velocity
or energy are used to measure job progress for LS-DYNA’s explicit
dynamic analysis calculations.
The graphical preprocessor LS-OPTui facilitates definition of the design
input and the creation of a command file while the postprocessor
provides output such as approximation accuracy, optimization
convergence, tradeoff curves, anthill plots and the relative importance
of design variables. The postprocessor also links to LS-PrePost to allow
the viewing of the model representing a chosen simulation point.
Typical applications of LS-OPT are