Skip to content. | Skip to navigation

Sections
Personal tools
Personal tools

Problem Description

 The problem is of a simplified vehicle moving at a constant velocity and crashing into a pole.

 vehicle_crash1.png vehicle_des_var2.png 
Fig. 1(a): Deformed vehicle after 50 ms Fig. 1(b): Design variables with part numbers

The problem illustrates the following features:

  • A simple single iteration optimization
  • Dealing with an infeasible design formulation
  • Use of composite functions
  • Trade-off study
  • Use of the LS-DYNA result interface
  • Discrete-continuous optimization

The criteria of interest are the following:

  • Head injury coefficient (HIC) of a selected point (15ms)
  • Component Mass of the structural components (bumper, front, hood and underside)
  • Intrusion computed using the relative motion of two points

Design variables:

  • The hood, front and underside (parts 3, 4 and 5 in Fig. 1(b)) are grouped under a single design variable: thood
  • The bumper (part 2 in Fig. 1(b)) is identified as another design variable: tbumper

Design Formulation

The design formulation is as follows:

  • Minimize HIC(15 ms) subject to Intrusion (50 ms) < 550 mm. The intrusion is measured as the distance between the nodes 167 and 432 (for the location of the nodes see Fig. 1).

Possible Approaches for Problem Solution

Downloads

Conclusion

  • The opimization problem has been summarized with the following conclusion.

 

  •