Some recommendations for characterization of composite panels by means of drop tower impact testing

Instrumented drop tower impact-test devices have been long used for inflicting impact damage onto test specimens for damage, tolerance characterization of composite panels. However, there are many considerations that need to be made regarding the test setup to avoid the inconveniences related to the acquisition and interpretation of the impact data. Because there are many advantages associated with this type of experiment, to benefit fully from the amount of information available from an impact test, a multiparameter approach needs to be used, and the entire test history needs to be interpreted. The previously demonstrated similitude between impact and quasistatic indentation tests is used to gain even further understanding in the mechanics of the event and its associated damage mechanisms. The fundamental characteristics of damage resistance tests are illustrated for the engineer being initiated to this type of work, particularly with regards to the understanding of impact traces. A summary of lessons learned is reported, and guidelines for the setup of the test and the interpretation of the results are given. A set of recommendations for best practice is given with the intent of laying down the foundation for a standard approach to future research programs.