Original Date: 07/10/2006
Revision Date: / /

The Finite Analysis Group has developed a static equivalent model for a dynamic process that has predicted – with near 100% accuracy – what will fail on a specific transportability stress test. This equipment has also been successfully used in other applications, most notably in the creation of a lifting fixture for removing the elevated equipment rooms.

Tobyhanna Army Depot (TYAD) has a requirement to measure peak accelerations on equipment for uses such as transportation. From the 1960s to1983, known inputs to a design such as stress forces and accelerations were very limited, with MIL-STD 810 and hand calculations used to determine these forces. Calculations were based on static loads only and often required costly rework on produced prototype items if calculations were incorrect.

From 1983 to 1989, TYAD acquired the ability to model using the AUTOCAD 2-D program for computer-aided design (CAD), which allowed for the development of two-dimensional drawings and models. This program did nothing for structural analysis in full, life-like simulation but did shorten the rework cycle because models were easily modified using the computer.

From 1989 through 1992, TYAD began implementing computer-aided engineering – the first full 3-D solids modeling. Mechanical properties such as weight and center of gravity could be calculated that allowed for an actual simulation of the design on the computer. However, this was independent of the finite element analysis (FEA) that was completed on the design.

From 1992 to 2002, TYAD merged FEA modeling requirements into the CAD design process and implemented dynamic forces analysis on its designs, developing static equivalent forces from the analysis that was crucial to simulating the stresses exerted on a design during Aberdeen testing. Simulation of this test was valuable, enabling failures of the test to be “designed-out” before a single weld was made on an actual prototype. TYAD is currently working with larger models, particularly full solid assemblies that can be run through this analysis.

For more information see the Point of Contact for this survey.