As electronics become smaller and more capable, they also become more sensitive to shocks and vibrations. Vulnerability is the price of sophistication, at least when it comes to electronics. As electronics become smaller and more capable, they also become more sensitive to shocks and vibrations. That’s even true for high-end, military-grade hardware, which often incorporates consumer off-the-shelf components.
Satellites, for instance, often rely upon laptop hard drives. Missiles, which are transported frequently, are at risk for shock from bumps and drops that may damage computerized components and break delicate connectors or solder joints. Even the paper and needle-based Richter-scale seismic monitoring devices are being replaced with analog-to-digital conversion modules.
The threat isn’t just from drop shocks. Vibration and resonance pose equally severe risks. For normal shipping, electronic components or final assemblies typically must withstand 1 G of random vibration at frequencies ranging from 3 to 50 Hz for 20 minutes. However, structural vibrations from the chassis of trucks and rail cars that carry these electronics peak at 70 Hz, and vibrations from rail joints range from 30 to 300Hz. Ship bulkheads and the cargo floors of aircraft each vibrate at frequencies from 2 to 200 Hz.
Proper packaging mitigates the effects of some of those vibrations and shocks. Packaging designers are seeking that “just right” Goldilocks spot that is rigid enough to prevent equipment from touching the sides of the box, and cushioned enough to absorb shocks and vibrations.
Even with proper packaging, however, risks occur. Changes in transportation mode or in environmental conditions alter the threats, and unexpected events? like drops from cranes or bumps into bulkheads? amplify them. Reliable packaging can only do so much. Shippers must know whether damage occurs, and when. With a thorough shock and vibration monitoring plan, shippers can identify damaged equipment before it is installed, and can mitigate future damage by adjusting logistics operations to mitigate risks.