finish
/clear
/TITLE, A 2-D, multiple compliance minimization problem subjected to volume constraint
/PREP7
BLC4,0,0,3,1          ! Create solid model (3 x 1 rectangle)
ET,1,82               ! Use 2-D solids. Type 1 is optimized
ET,2,82               ! Type 2 is not optimized.
MP,EX,1,118E9         ! Linear isotropic, material
MP,NUXY,1,0.3
ESIZE,0.05            ! Use a relatively fine mesh density
TYPE,1
AMESH,ALL             ! Free, rectangular-element meshing
NSEL,S,LOC,X,0,0.4    ! Select region not to be optimized
ESLN
TYPE,2
EMODIF,ALL             ! Define type 2 elements
ALLSEL    
NSEL,S,LOC,X,0
D,ALL,ALL,0           ! Fixed at X = 0
NSEL,S,LOC,X,3
D,ALL,ALL,0           ! Fixed at X = 3
FORCE = 1000          ! Value for applied load
NSEL,S,LOC,X,1
NSEL,R,LOC,Y,1
F,ALL,FY,FORCE        ! Define first load case
ALLSEL
LSWRITE,1             ! Write first load case
FDEL,ALL
NSEL,S,LOC,X,2
NSEL,R,LOC,Y,0
F,ALL,FY,-FORCE       ! Define second load case
ALLSEL
LSWRITE,2             ! Write second load case
FDEL,ALL
TOCOMP,MCOMP,MULTIPLE,2 ! Define multiple compliance function
                         ! "MCOMP" for topological optimization
TOVAR,MCOMP,OBJ          ! Define "MCOMP" as topological objective
TOVAR,VOLUME,CON,,50     ! Define "VOLUME" as topological constraint; 50 percent
                           volume reduction
TOTYPE,OC                ! Specify solution approach
TODEF                    ! Initialize topological opt.
/SHOW,topo,grph          ! Put graphics in a file (remove if interactive)
/DSCALE,,OFF
/CONTOUR,,2
TOLOOP,12,1              ! Perform no more than 12 iterations
FINISH
TOGRAPH,OBJ              ! Graph final objective (compliance) history
TOGRAPH,CON              ! Graph final constraint (volume) history
TOPRINT,OBJ              ! Print final objective (compliance) history
TOPRINT,CON              ! Print final constraint (volume) history
*GET,TITER,TOPO,,ITER        ! Get iteration counter
*GET,OCMP,TOPO,TITER-1,TOHO ! Get final compliance value