Design Examples

This section is intended to show examples of design problems which highlight the capabilities of the software and algorithms used.

 

Bag of Snakes

The first design example might be typical of an industrial or aerospace problem, and is setup as follows:

  • There are 25 tubes, each consisting of alternating straight, bend, straight, etc. segments.  
  • The starting point of the 25 tubes is a 5 by 5 regular grid on the yz plane.  The ending points are 25 random locations on a 5 by 5 regular grid at 90 degrees (on the xz plane).  For each tube ending location there are 6 location and direction objectives (xyz location and xyz direction vector), for a total of 150 objective parameters.
  • Each tube consists of 4 bend segments and 5 straight segments.
  • Each bend segment is 3 variables (bend radius, arc angle and rotation).
  • Each straight segment is 1 variable (length).
  • Therefore there are 17 variables per tube and 25 tubes for a total of 425 variables.  Each variable is also constrained to be a min/max length, radius, arc angle, rotation, so there are also 425 variable constraints.
  • In this example, each tube is also constrained to a total length so there are 25 length constraints.    The software allows length to be defined on individual, groups or all tubes, or can be a variable or statistical property such as variance (all tubes should end up being the same length).
  • The space constrains are a box shown as the 3d area in the plots.  In other problems space constraints can be setup as any combination of planar and point obstacles.
  • With 25 tubes, there are 325 permutations of tube-to-tube collisions

The collision constraints are a very expensive (n-squared) computation, so in this example, the tube-to-tube collision calculations are ignored until the xyz location and direction vector objectives are small.   

So, in this example, there are a total of 150 objectives, 425 variables, 450 constraints, and 325 collision permutations.  

 

 

 

Under Construction:  Temporary Client Video Files

 

 

 

 

 

 

 

 


 

 

A typical tube consisting of straight and bent segments

 

dbl-click for larger image

3d Rotation Transforms

 

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