Industrial environments impose continuous mechanical stress on electronic systems. Vibration from rotating machinery, mobile platforms, and structural resonance, combined with intermittent shock events such as impacts or abrupt stops, can degrade performance and shorten equipment life.
For integrators and engineers, vibration and shock are not secondary considerations. They define whether a system will operate reliably over time.
This article explains how mechanical stress affects electronics and how to address it using established engineering practices and recognized standards.
Vibration is a continuous mechanical motion characterized by cyclic displacement around an equilibrium point. It is typically defined by frequency, amplitude, and duration. In industrial environments, common sources include motors, pumps, compressors, and vehicle movement.
Shock is a transient event. It occurs as a sudden acceleration caused by impact, drop, or rapid deceleration. Unlike vibration, shock is short in duration but can introduce high peak forces.
Both forms of mechanical stress are commonly characterized using acceleration, typically expressed in units of g.
Standards such as MIL-STD-810 define environmental test methods for evaluating equipment under controlled vibration and shock conditions.
Mechanical stress affects electronic systems at multiple levels.
Repeated vibration can cause micro-movements in components and solder joints. Over time, this leads to fatigue and cracking, which can result in intermittent faults or complete failure.
Vibration can loosen connectors and cables, especially in systems without positive locking mechanisms. This introduces signal loss, data errors, or power interruptions.
Boards exposed to continuous vibration may flex. This flexing increases stress on mounted components and solder joints.
Traditional spinning drives are particularly sensitive to vibration and shock. Sudden impacts can cause head crashes or data corruption. Solid-state storage reduces this risk but does not eliminate it.
If the frequency of external vibration matches the natural frequency of a component or enclosure, resonance can amplify motion and accelerate failure.
These effects are well documented in reliability engineering and electronics design practices. The goal is not to eliminate vibration and shock, but to design systems that tolerate them.
Testing against recognized standards provides a baseline for performance.
MIL-STD-810 includes methods for vibration and shock testing across different scenarios, including transportation, operational use, and handling. It defines procedures such as:
MIL-STD-810 does not certify products. It defines test methods used to evaluate performance under specific environmental conditions.
Results depend on the specific methods applied and the conditions selected.
For engineers, referencing this standard ensures that testing aligns with widely accepted environmental conditions and repeatable procedures.
Effective protection begins at the design level.
Mounting systems using isolators or dampers reduce the transmission of vibration from the environment to the equipment.
Enclosures must resist deformation. A rigid structure prevents internal components from experiencing excessive movement.
Fasteners, brackets, and board supports reduce internal movement. Components should be fixed to prevent micro-shifts under vibration.
Use connectors with locking mechanisms. In high-vibration environments, circular connectors defined in military specifications are commonly used due to their retention strength.
Replacing mechanical drives with solid-state storage reduces sensitivity to shock and vibration.
Proper routing and strain relief prevent cables from transmitting vibration to connectors or components.
These approaches are standard in rugged system design and align with established engineering practices.
Design alone is not sufficient. Validation confirms performance under expected conditions.
Testing typically includes:
Equipment is evaluated not only for survival but for continued operation within specification.
Using procedures defined in MIL-STD-810 ensures consistency and comparability of results.
Different environments impose different stress levels.
Understanding the environment is required before defining requirements. Overdesign increases cost. Inadequate design increases failure risk.
Hardware designed for controlled environments often fails when exposed to sustained mechanical stress. Rugged systems address this by incorporating design features aligned with vibration and shock requirements.
VarTech Systems develops industrial computing platforms built to meet MIL-STD-810 environmental requirements for vibration and shock, intended for deployment in these conditions.
Within this context:
These systems are engineered to maintain structural integrity and operational performance under mechanical stress conditions defined during testing.
When specifying equipment, engineers should define:
These inputs determine whether a system meets application requirements.
Vibration and shock are inherent to industrial environments. They cannot be removed, only managed.
Reliable system design depends on understanding how mechanical stress affects electronics, applying appropriate design strategies, and validating performance against recognized test methods.
This approach ensures that equipment operates as intended, even under continuous mechanical stress.
Based in Clemmons, North Carolina, VarTech Systems Inc. engineers and builds custom industrial and rugged computers, monitors, and HMIs.
