Determination Of Impact Resistance Of Aluminum Panels For Machine Guards Using Regressions Of Dataset

An essential requirement for safety of workers consists of retaining ejected workpiece or tool fragments in case of a machinery rupture. Appropriate protective performance of the guard is demonstrated by means of an impact test carried out against a standardized projectile. The impact resistance (IR) Y is used as quantitative measure of an appropriate protective performance in terms of energy. It is defined as maximum kinetic projectile energy a safeguard can withstand. Based on knowledge of the ballistic limit velocity, an investigation on the statistical dispersion of IR is realized. In order to characterize the sheet's withstanding performance a certain number of test is conducted for different projectile’s velocities. In the present study, a probabilistic regression of failed impact tests is proposed for aluminum panels using a procedure already introduced in past research. A normal and a logistic distribution regression are compared in terms of their suitability for modeling the probability of failed impact tests. Logistic regression of the data appears to be less sensitive to the outcome of each test and the number of points used, in comparison to Gaussian regression. According to the findings, the so called “safe ballistic limit” corresponds to a 10% probability of test failure, although there isn't a perfect correspondence between logistic and Gaussian curves. To provide a more physical interpretation of the conducted tests, the new method proposed in this paper should be implemented while considering an energy reduction coefficient. This approach allows the Gaussian phenomenon to maintain the same characteristic. Additional tests are necessary to precisely define the withstanding capacity of the aluminum sheet and determine an appropriate safety factor for material guard design. These conclusions contribute valuable insights for enhancing the design and evaluation of safeguards in industrial settings, emphasizing the importance of continued research to ensure a proper safety of workers in environments prone to ejection risk.