The Dynamics of a Small-Scale Portable Electronics Device Under Impact Stimuli

Abstract

The reliability of portable electronic devices is of critical importance due to the consumer boom in mobile telephony in recent years. Impact is a key driver of failure in portable electronics and, in current design practice, extensive testing is used in conjunction with finite element simulations to ensure product reliability under impact stimuli. Testing is time-consuming and expensive – both free-drop and constrained drop tests are usually applied – and simulation techniques are very computationally intensive. The response of portable electronic devices to impact is currently not well understood, and there is clear need for investigation into the range of acceleration levels experienced by a representative model of a portable electronic device on impact. In this paper, free-drop testing was carried out on test vehicles representative of a typical mobile phone in order to acquire acceleration data from impact events. Drop test vehicles from Nylon and aluminium were used to provide a means of comparison for diverse material properties. The primary conclusion was that the dynamics of each drop event were highly sensitive to the initial conditions of the drop test, which was evident from wide variances in the acceleration data.