Finite Element Analyses on Dynamic Responses of a Portable Instrument Subjected to Drop/Impact

Abstract

Portable electronic products such as portable instruments are susceptible of drop impacts. Therefore the effects of impact and shock on the integrity of the instrument body as a whole and the internal components including the printed circuit board (PCB) are important reliability issues and hence need to be addressed. The impact orientation is one of the major factors that influence the dynamic responses of the instrument structure. This paper presents a study, using ANSYS/LS-DYNA, of drop/Impact responses of the body structure of commercially available potable measurement instruments. The instrument is set to free fall drop with three impact angles 0 , 45 , and 90. The responses including the variations of stress and strain are evaluated on the housing cases and internal PCBs of the instrument. The results show that the subsequent impacts that follow the first impact also contribute noticeable influences to the structure of the instrument. The results of this study can be the bases for the design of drop concerns of general portable measurement instrument.