This example involves the shape optimization of the connecting rod of a slider crank. The mass of the connecting rod is to be minimized. Initial velocity is applied to the block of the model. The stress of all connecting rod elements must be less than an allowable value.

Slider crank

Four design variables follow:

Input decks for the design are as follows.

SUBCASE     1

 MBSIM   = 1

 INVEL   = 2

 DESSUB  = 10

 SPC     = 10

$

BEGIN BULK

$

DESVAR      1   UPPER0.0     -1.0    2.0

DESVAR      2   LOWER0.0     -1.0    2.0

DESVAR      3LEFT_OUT0.0     -1.0    1.0

DESVAR      5RIGHT_OU0.0     -1.0    1.0

$

DRESP1  1   MASS    MASS    PSOLID                      18

DRESP1  2   STRESS  STRESS  PSOLID         SVM              18

$

DCONSTR  10    2     -100.E1 100.E1

 

DVGRID*         1       9925511       0      1.0

*       -1.568286121E-02-3.884642199E-02-6.483015791E-10

                       :

                       :

The final design appears as follows:

The optimum design

The input file can be found in <install_directory>/demos/hwsolvers/optistruct/sc_design.fem.