Improved sensitivity testing of explosives using transformed Up-Down methods

TLDR: In this paper, the authors compare the effectiveness of the TUD and Bruceton up-down testing in the context of explosive sensitivity and show that TUD is more useful for many cases but that they do require more tests as a consequence.

Abstract: Sensitivity tests provide data that help establish guidelines for the safe handling of explosives. Any sensitivity test is based on assumptions to simplify the method or reduce the number of individual sample evaluations. Two common assumptions that are not typically checked after testing are 1) explosive response follows a normal distribution as a function of the applied stimulus levels and 2) the chosen test level spacing is close to the standard deviation of the explosive response function (for Bruceton Up-Down testing for example). These assumptions and other limitations of traditional explosive sensitivity testing can be addressed using Transformed Up-Down (TUD) test methods. TUD methods have been developed extensively for psychometric testing over the past 50 years and generally use multiple tests at a given level to determine how to adjust the applied stimulus. In the context of explosive sensitivity we can use TUD methods that concentrate testing around useful probability levels. Here, these methods are explained and compared to Bruceton Up-Down testing using computer simulation. The results show that the TUD methods are more useful for many cases but that they do require more tests as a consequence. For non-normal distributions, however, the TUD methods may be the only accurate assessment method.