OPTIONS

Determines the attributes (nodal boundary conditions) of the FE model that should be loaded in TOSCA_PREP and TOSCA_OPT and which other actions should be considered during loading (for example, automatic determination of the surface nodes). This command must be defined before the FEM_INPUT command in the parameter file to be known during model import.

By default, in TOSCA_PREP only the nodes and elements are loaded with the command FEM_INPUT. In TOSCA_OPT, all required stresses and displacements are loaded. In addition, parameters for the output of information during the optimization might be defined.

Note: The OPTIONS command must be before the FEM_INPUT command in the parameter file.

This page discusses:

See Also
In Other Guides
Options for Loading FE Data (OPTIONS)

Read Parameters

READ_SF_IDENT

Determination of the surface nodes for shape optimization while reading the finite element model.

= ON

Surface nodes are identified.

= OFF

Surface nodes are not identified.

READ_SF_MIDNODE

Treatment of the midside nodes during the determination of the surface nodes.

= ON

Midside nodes are considered during the determination of the surface nodes.

= OFF

Midside nodes are not considered during the determination of the surface nodes.

READ_BC

Treatment of the boundary conditions of the finite element model.

= ALL

Boundary conditions are read.

= NOT

No boundary conditions are read.

= ID, <id_1>, <id_2>, ...

Only some boundary condition sets are read (dependent on the interface).

READ_LOAD

= ON

= OFF

Loaded nodes / elements are identified while reading the finite element model.

READ_ELEM_QUALITY

= ON

= OFF

Check the element qualities during the import of the finite element model.

GROUP_NAME_COMPATIBILITY

= YES

= NO

Compatibility mode for group names: If a group defined in the solver input file contains blanks, two groups are created: one where the blanks are replaced with underscores '_' and the other with blanks in the name.

ALLOW_MISSING_LOADCASES

= YES

= NO

Controls the behavior of the preprocessor if no load case is found in the first solver input file: a value of YES would let the preprocessor continue, while the default value of NO triggers an error message and stops the execution. This option is useful in a multiple input file scenario where the load case definition(s) might appear in the second, third, etc. input files.

Parameters for the Optimization Run

READ_RESULTS

Checking the presence of the finite element results.

= STRICT

Optimization is stopped if results are missing.

= IGNORE

Optimization is continued even if some results are missing.

IGNORE_NUM_OF_CONSTRAINTS

= YES

= NO

Continue with the optimization if the definition of the problem exceeds the number of 50 constraints.

IGNORE_NUM_OF_OBJF_TERMS

= YES

= NO

Continue with the optimization if the definition of the problem exceeds the number of 50 objective functions terms.

IGNORE_OBJ_FUNC_TYPE

= YES

=NO

Ignore the limitation for MINMAX objective function for controller-based optimization.

SHAPE_FORCE_VOLUME

= ON

= OFF

Shape optimization forces volume constraint in the first design cycle.

It is not recommended to turn this setting OFF. If the mesh is distorted in first iteration, your volume constraint is probably too small or large. Changing this to OFF will simply cause more design cycles before the mesh is corrupted.

SHAPE_AUTO_REMOVE_INNER_NODES

= ON

= OFF

Shape optimization removes inner nodes from design area automatically. Inner nodes might still cause trouble by certain DVCON_SHAPE where inner nodes are not allowed.

SHAPE_FORCE_MIDSIDE_INTERPOL

= YES

= NO

Shape optimization interpolates midside nodes linear if one of the neighbors has been moved.

If set to YES, midside nodes are always interpolated for mesh smooth elements.

IGNORE_UNKNOWN_NODES

= YES

= NO

If an input file references nodes that are unknown to Tosca Structure, these nodes can be ignored and a warning is printed (YES) or the optimization is aborted (NO).

DISABLE_TET_SELECTION_DETECTION

=NO

= YES

If tetrahedral elements are located at a corner in such a way that the corner node belongs solely to that element and not all faces of the element shall be considered for normal direction calculation, special effort must be taken to determine the correct or expected direction. This special effort can be disabled by setting this option to YES.

Parameters usable with Abaqus

USE_ABQ_SENS

This option is obsolete and has no influence on the optimization procedure.

SENS_CALC_MODE

=AUTOMATIC/SOLVER/TOSCA/HYBRID

Controls whether the DRESPs values and sensitivities should be calculated by the solver or by the optimization system. If this option is set to AUTOMATIC, the optimization system will chose the best calculation mode. If HYBRID is chosen the design response values and the corresponding sensitivities will be calculated by solver if they are supported and by the optimization system for all other cases. To be able to use older versions of Abaqus (older than 3DEXPERIENCE2017x FP1721), set SENS_CALC_MODE = TOSCA.

SOLVER_RUN_MODE

=AUTOMATIC/SEQUENTIAL/SIMULTANEOUS

Controls whether the solver should be called (check out licenses, run preprocessor, solve the modified job, output the results, shut down) in each iteration in sequential sessions or a single/simultaneous solver session (start the solver once at the beginning of the optimization, communicate modifications of the model by distribution tables, and solve the job in each iteration, shut down the solver by the end of optimization) should be started. If this option is set to AUTOMATIC the optimization system chooses the best solver run mode.

ABQ_SENS_ABSENT_SET_ZERO

=YES/NO

In case of using the sensitivities calculated by Abaqus, this option controls whether to set the missing sensitivity values to zero or not. This option should be set, for example, when *model change command is used in the solver input file.

FORCE_SIM_YES

=FALSE/TRUE

In case of using the sensitivities calculated by Abaqus, if mode tracking is present in the analysis this option converts any SIM=NO command to SIM=YES in the input file.

KEEP_SFILM

=TRUE/FALSE

This option turns off the modification of *sfilm card during the optimization. It allows the user to keep the original surface film boundary condition throughout the optimization even if the actual surface has changed.

USE_ABQ_UNROLL

= YES/NO/ON/OFF/SELECTIVE

Controls the enrolling of *LOADCASEs inside a *STEP.

Note: SELECTIVE means that the unrolling only happens if the first *STEP is a preloading step

NODAL_MODIFICATION

= DISTRIBUTION_TABLE /INPUT_FILE

Controls how node modifications from shape optimization are communicated to the FE solver. Only usable in combination with solver sensitivities.

DISTRIBUTION_TABLE: Write node modifications only in the distribution table.

INPUT_FILE: Write node modifications directly into the solver input file.

DRESP_GROUP_OPER_AGGREGATION

= ON / OFF

This option controls if the group in the design response will be evaluated using the existing Tosca algorithm or a new algorithm introduced in 2021x based on Abaqus sensitivities. The new algorithm provides performance benefits in case of large groups or multiple load cases. The default is OFF means only the existing algorithm will be used.

Parameters usable with MSC Nastran®

MSC_NASTRAN_BAILOUT

= TRUE/FALSE

This option writes PARAM BAILOUT -1 to the modified input file. It ensures that the Nastran analyses will not abort even if there are errors in the model.

Output Parameters

CONSTRAINT_OUTPUT

Controls the output of the CONSTRAINTs in TOSCA.OUT.

= DEFAULT

Default output is that a satisfied CONSTRAINT < 1.0 for the normalized output. It does not matter if the CONSTRAINT is LE_VALUE, GE_VALUE or EQ_VALUE.

= STANDARD

Constraint value is normalized with the constraint value.

= NONORM

Do not normalize constraints.

REPORT_FILE

= STANDARD

= ALL

= NONE

Descriptors of what is printed to the file optimization_report.csv. See also section Remarks.

= D,F,W,R,C

See "Code" in the table at section Remarks.

PLOT_CTRL_INP_MINUS_REF

= YES

= NO

Plot the CTRL_INPUT with the subtracted reference value or with its original value.

This can make differences if more than one entry is present for the objective function.

DEFAULT_SMOOTH

= ON

= OFF

Default smoothing task (settings corresponding to smooth_templates.mac). Only available for topology optimization.

DEFAULT_REPORT

= ON

= OFF

Default report generation (settings corresponding to report_templates.mac).

DEFAULT_REPORT_ON_ERROR

= ON

= OFF

Default report generation when optimization job fails

DEFAULT_REPORT_GROUP

= ALL_ELEMENTS

= __DESIGN__

= __MODEL__

= <group_name>

Report generated for all elements, specified group (from analysis model or parameter file) or design area.

DEFAULT_SMOOTH_ISOVALUE

= <value>

Iso value for smoothing (between 0 and 1).

DEFAULT_SMOOTH_VOLUME

= <value>

Target volume for smoothing, relative value set by user (between 0 and 1)

DEFAULT_SMOOTH_GROUP

= ALL_ELEMENTS

= __DESIGN__

= __MODEL__

= <group_name>

Smoothing performed for all elements, specified group (from analysis model or parameter file) or design area.

Remarks

  1. The REPORT_FILE item might be used to change the output in the file optimization_report.csv: Iteration number and value of the objective function (OBJ_FUNC) is always written to optimization_report.csv. This is the only output with option NONE. The default (STANDARD) output is: DRESP, OBJ_FUNC:DRESP, and CONSTRAINT values. All output in following table is active with option ALL.
  2. Using the letter codes in the REPORT_FILE item the output might be customized as shown in the table below:

    Output name

    Description

    Code

    DRESP

    All DRESPs referenced in OBJ_FUNC real values.

    D

    OBJ_FUNC:DRESP

    The value of DRESP in OBJ_FUNC [weight*(dresp_value – ref_value)].

    F

    OBJ_FUNC: DRESP:Weight

    Weight of DRESP in OBJ_FUNC.

    W

    OBJ_FUNC:DRESP:Ref

    Reference value of DRESP in OBJ_FUNC. This value can be interesting for shape optimization.

    R

    CONSTRAINT

    The value of DRESP in CONSTRAINTs

    C

  3. Default result reports and smooth runs can be activated in the parameter file to be created after the optimization (an example can be found in the macro report_templates.mac). To get a report with your topology optimization results including the smoothed model with a defined iso value, you could add the following to your parameter file:
  4. 
    OPTIONS
      DEFAULT_SMOOTH                = ON
      DEFAULT_REPORT                = ON
      DEFAULT_REPORT_GROUP          = ALL_ELEMENTS
      DEFAULT_SMOOTH_ADD_TO_REPORT  = ON
      DEFAULT_SMOOTH_VOLUME         = <value>
      DEFAULT_SMOOTH_GROUP          = ALL_ELEMENTS
    END_