Project Lab – Tubular Structure

The objective of this project is to evaluate the proposed structure under static loading conditions and compare to displacement requirements. In other words – apply different optimization methods and learn how structural optimization “drives” the design.

The structure supports a 200 kg mass from the overhanging tube. The structure is currently made of standard steel square tubes 2”x2”x0.120”. The structure is bolted at the 5 bottom plates, which number can be reduced.

3 loadcases are evaluated:

  • 2g downwards (dynamic installation of the mass)
  • 1g downwards + 0.5g lateral (X) (seismic load)
  • 1g downwards + 0.5 lateral (Y) (seismic load)

Displacements requirements:

  • Less than 5mm for the 2g downwards scenario
  • Less than 7mm for the seismic loads

Baseline Structure:

Additional Information – Baseline Structure

  • Mesh tube structure with 8-mm shells (midsurface: use offset+planes option in the “extraction options” menu).
  • Use shell elements for the welds (5mm thick).
  • Use 6-mm washers for the bolts of the base plates.
  • Use a RBE2 element to connect lump mass (over a 50mm length at end of overhang tube).
  • Assume Steel for all components: E = 210,000 MPa; Poisson Ratio = 0.3, Density = 7.85e-9 Mg/mm3 , Yield strength = 320 MPa
  • Use “GRAV” card image for g load collectors (g=9810 mm/s2)

Expecting the structure to be over-designed, minimize its mass using different approaches:

Gauge optimization without / with discrete variables (view tutorial)

2D shell topology optimization (view tutorial)

3D topology optimization (view tutorial)

3D topology optimization of available volume (view tutorial)

Shape optimization (cross-section dimensions and thickness) (view tutorial)

1D model topology optimization (view tutorial, model file)

View “short” summary

1D model topology optimization (view tutorial, model file)