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Problem Description

Reliability Based Design Optimization (RBDO) includes uncertainties of design variables in the optimization.



The example demonstrates:

  • Reliability Based Design Optimization (RBDO)
  • Creating statistical distributions and assigning them to design variables
  • Probabilistic constraints


Problem Description

The problem is of a simple two-bar truss. It has two variables: the crosssection area of the bars (Area) and the leg width (Base). Both the thickness and the leg width have uncertainties associated with them. A value of the Base variable and the Area variable must be obtained that minimizes mass while respecting a probability of not exceeding the allowable stress value.


Design Formulation

The design formulation is as follows:

  • Minimize the weight of the structure subject to the probability of the maximum stress in the bars exceeding the failure stress is limited.


Problem Solution