Abstract
Research and/or Engineering Questions/Objective
In this paper, we describe the development of finite element model of the Mobile Progressive Deformable Barrier (MPDB) considering honeycomb dynamic crush strength. A frontal crash test procedure using MPDB is studied for vehicle frontal compatibility assessment. MPDB honeycomb has complicated structure, and a honeycomb model should be newly developed for a MPDB crash simulation.
Methodology
An MPDB model which had honeycomb static crush strength was developed, and a flat rigid wall test was simulated. The simulation result showed that barrier load was smaller than test result. From this result, we assumed honeycomb dynamic crush strength had to be studied. To clarify the difference between honeycomb dynamic and static crush strength, Drop Tower Test was carried out using test pieces cut from MPDB honeycomb. The load measured in the Drop Tower Test was larger than the load estimated from honeycomb static crush strength. This difference assumed to be caused by air in the honeycomb. Using Drop Tower Test results, a honeycomb model was developed considering dynamic crush strength. An airbag model was used to represent the dynamic crush strength. Considering leaks of the internal air and so on, the airbag model was so modeled that it showed good correlation with Drop Tower Test results.
Results
An MPDB model considering honeycomb dynamic crush strength was developed. The precision of the developed MPDB model was improved in a flat rigid wall test. Also a simulation of a crash test was carried out using the developed MPDB model and a small vehicle. The calculation result showed good correlation with the test result. In addition, a simulation of a crash test not considering honeycomb dynamic crush strength was carried out and compared to the above calculation result. In case that honeycomb dynamic crush strength was not considered, honeycomb front deformation increased more than 100mm.
Limitations of this study
The MPDB model was developed using limited Drop Tower Test result. The developed MPDB model cannot necessarily be applied to other vehicle.
What does the paper offer that is new in the field including in comparison to other work by the authors?
The developed MPDB model was considered honeycomb static and dynamic crush strength independently. So the effect of honeycomb dynamic crush strength could be evaluated.
Conclusions
The MPDB model was developed, and it was confirmed that the developed MPDB model showed good correlation with the test result. In addition, the influence of honeycomb dynamic crush strength on honeycomb deformation was evaluated.
Key Words: MPDB; Finite element model; Honeycomb; Dynamic crush strength