Youda He wrote:
> =A0We are developing a controller board that will be mounted on a
> machine, the machine will vibrate (shake) heavily, but should not
> exceed 3g. We have no control which direction it goes, so the circuit
> board need to sustain vibration in all directions. =A0On top of that,
> the environment is moist, we have some modules mounted with heavy
> insulation inside. The insulation also added weight to the modules
> (the modules are about the size of a deck of poker cards. places wide
> side down to circuit.
>
> =A0What are the good ways to secure the modules and circuit board that
> can sustain the vibrations?

Probably you need to look through some books on  packaging of
electronics like this one:

Practical Guide to the Packaging of Electronics, Second Edition:
Thermal and Mechanical Design and Analysis (Dekker Mechanical
Engineering)

http://www.amazon.com/Practical-Guide-Packaging-Electronics-Second/dp/14200=
65319/ref=3Ddp_ob_title_bk

=3D=3D=3D
This volume supplies a solid foundation for heat transfer, vibration,
and life expectancy calculations. Topics discussed include various
modes of heat removal, such as conduction, radiation, and convection;
the impact of thermal stresses; vibration and the resultant stresses;
shock management; mechanical, electrical, and chemically induced
reliability; and more.
=3D=3D=3D

Also quick gooling gives:

Steinberg D.S., 1973,
Vibration Analyses for Electronic Equipment, John
Wiley and Son, NY.

Laura P.A.A., Ercoli L., and., 1995,
Dynamic Stiffening of a Printed Circuit Board,
Acustica, Vol. 81, pp 196-197.

Wong T-L, Stevens K.K., and Wang G.,
Experimental Modal Analysis and Dynamics Response Prediction of PC
Boards With Surface Mounted Electronic Components,
ASME Journal of Electronic Packaging, Vol. 113, pp. 244-249, 1999.

Suhir E.,
Predicted Fundamental Frequency of Vibration of a Heavy Electronic
Component Mounted on a Printed Circuit Board,
ASME Journal of Electronic Packaging, Vol. 122, No 1, pp. 3-5, 2000.

Lim G.H., Ong J.H, and Penny J.E.T.,
Effect of Edge and Internal Point Support of a Printed Circuit Board
Under Vibration,
ASME Journal of Electronic Packaging, Vol. 121, No 2, pp. 122-126, 1999.

Steinberg D.S.,
Vibration Analysis for Electronic Equipment,
John Wiley & Sons, 2000.

G.S.Aglietti, A Lighter
Enclosure for Electronics for Space Applications,
Journal of Aerospace Engineering, part G Vol 216-3, pp 131-142, 2002.

G.S. Aglietti,
On the use of anti-vibration devices for PCBs in Space Application
ASME Journal of Electronic Packaging

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