Using the Package Profiler

Using the Package Profiler to Greatly Improve Equivalent Drop Height Measurement


In the past, several methods have been used to estimate an "equivalent drop height". Of course, no package experiences a pure free-fall drop height every time -- quite the contrary. Hence, the need to typify the many impacts, bumps and shocks that occur to a package in the field. Understanding this can help you to develop more accurate and realistic packaging tests in your lab, avoid overpackaging, and clarify understanding of your distribution environment.

All methods of computing an equivalent drop height involve estimating or computing the coefficient of restitution. The Coefficient of Restitution (e) is the measure of returned energy divided by input energy. For instance, one can measure the coefficient of restitution of a rubber ball easily. Just drop it onto a hard, even surface from a known height, and measure its rebound height. Rebound height divided by the initial drop height is equal to e.

A ball is simple - it has no sides, corners or edges, and it is the same no matter what point hits the floor. It's not nearly as easy for a package. One of the ways to do it is to measure impact velocity and return velocity. Return velocity divided by impact velocity equals e. Unfortunately, this method is only accurate in a controlled lab environment.

The Package Profiler is a new method of accurately determining the e of a package, determining the e for all points on the package's surface, then using that "profile" to in turn process data for equivalent drop heights. The result far exceeds all other methods of determining equivalent drop height.