Adams Basic Package > Adams View > View Command Language > simulation > simulation multi_run optimization

simulation multi_run optimization

In general, an optimization problem is described as a problem of minimizing or maximizing an objective function over a selection of design variables, while satisfying various constraints on the design and state variables of the system.

Format:

 
simulation multi_run optimization
model_name =
existing model name
sim_script_name =
Existing simulation script
variable_names =
Existing variable
objective_name =
Existing objective
measure_name =
existing measure
output_characteristic =
minimum/maximum/ average/ last_value/ absolute_minimum/ absolute_maximum/ rms/ standard_deviation
constraint_names =
existing optimization constraint
characteristic =
minimize/maximize

Example:

 
simulation multi_run optimization &
model_name =
.MODEL_1 &
sim_script_name =
.MODEL_1.Last_Sim &
variable_names =
DV2 &
objective_name =
.MODEL_1.OBJECTIVE_1 &
characteristic =
minimize

Description:

 
Parameter
Value Type
Description
model_name
Existing Model
Specifies the name of the model.
sim_script_name
Existing Simulation Script
Enters the name of your simulation script or uses the default.
variable_name
Existing Variable
Specifies an existing variable name that has to be used for the optimization study.
constraint_ names
Existing Optimization Constraint
Specifies the names of the constraints.
characteristic
Minimize/maximize
Specifies whether to minimize or maximize the characteristic
output_characteristic
Minimum/maximum/ Average/ Last_value/ Absolute_minimum/ Absolute_maximum/ Rms/ Standard_deviation
If you are using a measure, set the design objective’s value. For a measure, enter minimum, maximum, average, last_value, absolute_minimum,rms,standard_deviation and absolute_maximum of the measure.
objective_name
Existing Objective
Enters the name of the design objective.
measure_name
Existing Measure
Enters the name of an existing measure to be used for the doe.

Extended Definition:

1. The simulation script contains options or commands to drive the simulation.
2. Objectives usually involve simulation results, but they are not required to do so. You can create an objective that depends only on the model data, such as overall weight or size. You can then use Adams View to vary, or even optimize, the design variables and immediately see the results on the model
Typical objectives include time, energy, or displacement from a path.
3. The objective function is a numerical representation of the quality, efficiency, cost, or stability of the model. You decide whether the optimization chooses to find the minimum or maximum of the function. The optimum value of this function corresponds to the best design possible using that particular mathematical model. Examples of objective functions include execution time, energy (effort) required, and total material costs.

Tips:

1. You can also browse for the script name in the Database Navigator. Right-click in the text box, point to Simulation_Script, and then select Browse. Select the model in the Database Navigator, and then select OK.
2. If you are preparing for an optimization, you can create constraint objects to limit the changes that the optimizer can make. Often an optimization finds a configuration that optimizes the objective you provided, but is unrealistic because it violates overall design constraints such as weight, size, speed, or force limits.
To avoid results that violate the design constraints, you can create constraints for the optimization. The optimization analysis improves the objective as much as possible without violating the constraints.