Using finite element (FE) analysis to simulate drop impact is widely adopted by the consumer electronics industry in the design process of portable devices. Most of such simulations model impact surface as a rigid or simple elastic surface. While this approach is valid for many common hard surfaces such as wood, tile, or concrete, it often does not provide a realistic risk assessment if the impact surface is a soft surface such as carpet. This paper describes a methodology to create a material model for carpeted impact surface that is suited for FE drop simulation. A multilayer hyperelastic–viscoelastic material model is used to model the mechanical response of the carpet under mechanical impact. Quasi-static and impact testing on the industrial carpet were performed to calibrate the model parameters with the help of optimization. Validation of the model was done by comparing the simulation predictions with measurements from the impact tests performed at different heights. Much better correlation between experimental measurements and simulation predictions were observed when using the multilayer hyper-viscoelastic model for carpet than using a single layer homogenous model. This approach can provide a better estimate and a more accurate representation for device drop risk on carpeted surfaces for design and development of portable products. The methodology can also be used to derive material models for other similar impact surfaces.

References

References
1.
Meng
,
J.
,
Douglas
,
S. T.
, and
Dasgupta
,
A.
,
2016
, “
MEMS Packaging Reliability in Board-Level Drop Tests Under Severe Shock and Impact Loading Conditions—Part I: Experiment
,”
IEEE Trans. Compon., Packag. Manuf. Technol.
,
6
(
11
), pp.
1595
1603
.
2.
Meng
,
J.
, and
Dasgupta
,
A.
,
2016
, “
MEMS Packaging Reliability in Board-Level Drop Tests Under Severe Shock and Impact Loading Conditions—Part II: Experiment
,”
IEEE Trans. Compon., Packag. Manuf. Technol.
,
6
(
11
), pp.
1604
1614
.
3.
Yau
,
Y. H.
, and
Hua
,
S. N.
,
2011
, “
A Comprehensive Review of Drop Impact Modeling on Portable Electronic Devices
,”
Appl. Mech. Rev
,
64
(
2
), p.
020803
.
4.
Kallolimath
,
S.
, and
Zhou
,
J. J.
,
2016
, “
Optimal Shock Pulse in a Drop Test Simulation of Standardized Board for Uniform Shock Response
,”
ASME J. Electron. Packag.
,
138
(
4
), p.
041001
.
5.
Baranyai
,
T.
, and
Várkonyi
,
P. L.
,
2018
, “
Optimal Mechanical Design of Electronic Devices for Shock Protection
,”
IEEE Trans. Compon., Packag. Manuf. Technol.
,
8
(
9
), pp.
1533
1543
.
6.
Yamazaki
,
T.
,
Ono
,
T.
,
Utsumi
,
S.
,
Misaji
,
K.
, and
Kamata
,
M.
,
2004
, “
Modeling of Floor Carpet on Vibration and Structure-Bone Noise Transmission
,” International Congress on Acoustics (ICA), Kyoto, Japan, Apr. 4–9, Paper No. IV-2923-2926.
7.
Deiters
,
T. A.
,
Baker
,
M.
,
Indermuehle
,
K. C.
, and
Engelhardt
,
C. W.
,
2000
, “
Using Analysis to Design for Drop or Other Shock Environments
,” International Modal Analysis Conference (
IMAC
)-XVIII: A Conference on Structural Dynamics, San Antonio, TX, Feb. 7–10.http://www.gbv.de/dms/tib-ub-hannover/313070512.pdf
8.
Celik
,
N.
, and
Koç
,
E.
,.
2007
, “
An Experimental Study on Thickness Loss of Wilton Type Carpets Produced With Different Pile Materials After Prolonged Heavy Static Loading—Part 2: Energy Absorption and Hysteresis Effect
,”
Fibres Text. East. Eur.
,
15
(
3
), pp.
87
92
.http://www.fibtex.lodz.pl/2007/3/87.pdf
9.
Vuruşkan
,
D.
,
Sarıoğlu
,
E.
,
Çelik
,
H. I.
, and
Kaynak
,
H. K.
,
2017
, “
Compression Properties of Woven Carpet Performance Under Dynamic Loading
,”
Periodicals Eng. Nat. Sci.
,
5
(
2
), pp.
181
186
.
10.
Dunlop
,
J. I.
, and
Jie
,
S.
,
1991
, “
The Dynamic Mechanical Response of Carpets: An Alternative Measurement Technique
,”
J. Text. Inst.
,
82
(
3
), pp.
353
359
.
11.
Grover
,
G.
,
Zhu
,
S.
, and
Twilley
,
I. C.
,
1993
, “
Dynamic Mechanical Properties of Carpet Yarns and Carpet Performance
,”
Text. Res. J.
,
63
(
5
), pp.
257
266
.
12.
Fung
,
Y. C.
,
1969
,
A First Course in Continuum Mechanics
,
Prentice Hall
,
Englewood Cliffs, NJ
.
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