Experimental and Analytical Study of Free-Fall Drop Impact Testing of Portable Products

Portable products can suffer critical damage due to drop impact and thus, such load cases must be taken into account in the conceptual and detailed design phases of such products. One method explored in the current study for alleviating the peak accelerations resulting from impact is to isolate fragile components from the product housing using internal shock mounts. There is a lack of studies that address this method in a systematic and reliable manner. This paper presents an experimental and analytical study on the dynamic behaviour during impact of portable products with internal shock mounting. Using a special drop tower with guiding frame for controlled-angle free-fall drop impact, representative products are dropped at different angles and the acceleration is recorded both on the outer case and on an internally-mounted plate. A simplified analytical procedure, suitable for conceptual design purposes, is proposed for predicting the resulting dynamic response. The work affirms the suitability of guide-and-release facilities in impact experiments; additionally, it may facilitate the conceptual design for impact resistance of portable products.