Why real world testing is more important than lab testing in embedded products

When companies build a new embedded product, the instinct is to validate it inside a clean and controlled laboratory environment. It feels safe, predictable and measurable. Engineers have full control over instruments, temperature, power and timing. If the device behaves correctly in the lab, it often creates the illusion of readiness.

However, the real world is not a laboratory. It is uneven, noisy, unpredictable and often hostile. Embedded devices rarely fail on the engineer’s desk. They fail in factories with unstable power, in agricultural fields with humidity swings, inside machinery vibrating at hundreds of hertz, or in outdoor enclosures that heat up far beyond standard test conditions.

In modern hardware development, real world testing is not a final stage. It is a fundamental ingredient of building reliable devices that survive years of operation. The difference between a product that succeeds and one that fails repeatedly in the field almost always comes down to the depth and realism of its testing strategy.

Why laboratory testing is never enough

Laboratory testing focuses on ideal conditions.

The environment is stable, the power supply is clean, and the device usually operates at room temperature.

There is no vibration, no unexpected mechanical stress, no sudden power disturbances and no humidity fluctuations.

In these controlled environments, many real problems remain invisible. Timing behaviours may not appear. Sensors behave more accurately than they will outdoors. Wireless signals stay stable because there is no interference. Even mechanical imperfections may remain hidden.

A device can look perfect in the lab while being unprepared for the environment it will eventually face.

Vibration

Vibration is one of the most underestimated stress factors. Devices installed near motors, compressors, pumps, industrial equipment or vehicles are exposed to continuous mechanical energy.

Real world vibration can lead to:

• loose connectors

• broken solder joints

• damaged mechanical switches

• intermittent cable connections

• microfractures in PCBs

• unstable sensor readings

Standard lab benches do not reveal these issues. Only vibration tables and long duration testing reproduce the real stress the product will face.

 

Source: ResearchGate.

Humidity and condensation

Humidity changes rapidly and unpredictably. Condensation forms when temperature changes fast, especially when devices transition between indoor and outdoor environments.

Moisture can:

• corrode metal

• change PCB surface impedance

• create leakage currents

• cause sensor drift

• weaken adhesives and plastics

Real world humidity profiles are chaotic, and only environmental chambers combined with thermal cycling expose these weaknesses.

Temperature cycling

Temperature cycling causes materials to expand and contract at different rates. This mechanical movement stresses solder joints, connectors, enclosures and component interfaces.

Temperature cycling reveals:

• cold start failures

• thermal drift

• mechanical deformation

• timing instability

• cracks in solder or plastic parts

Real world temperature swings are never stable. They change rapidly depending on load, weather and installation environment.

Noisy power lines

Power in industrial environments is rarely clean. Heavy machinery, long cable runs and unpredictable loads create electrical noise that does not appear in laboratories.

Noisy power lines lead to:

• brownout induced memory corruption

• unexpected microcontroller resets

• unstable ADC readings

• timing drift

• destructive voltage spikes

A device that works flawlessly on a bench supply may reboot continuously in an actual factory.

 

Machines that recreate real world stress

While no single machine can reproduce everything that happens in the field, engineers use a combination of specialised testing equipment to simulate the most important categories of stress.

 

Vibration tables

Simulate mechanical vibration and shock seen in vehicles, factories and industrial equipment.

Source: Humboldt

 

Temperature and humidity chambers

Reproduce extreme temperatures, rapid transitions, condensation and humidity swings.

Source: Humboldt

HALT systems

Highly Accelerated Life Testing, combining extreme temperature and vibration to reveal design weaknesses early.

Source: Electron Test Equipment

HASS systems

Highly Accelerated Stress Screening, used in production to catch assembly defects. 

Source: Faraday Defense

HALT vs HASS

Source: TT Electronics

EMC chambers

Test radiated and conducted emissions, immunity to electrical noise, ESD and surges.

Drop and shock testers

Simulate accidental drops, shipping impacts and mechanical shock.

Source: ResearchGate

Dust and ingress chambers

Replicate particulate exposure for IP rated devices.

These machines bring engineers closer to real world conditions, yet even with all this equipment, nothing replaces final testing in the actual field environment.

Source: Relia Test labs

  

Field pattern analysis: the final and most important layer of testing

Field testing exposes behaviours that even the most advanced chambers cannot fully replicate. Real environments introduce unpredictable combinations of vibration, temperature, humidity, interference, user behaviour and power instability.

Field pattern analysis reveals:

• repetitive failure modes

• environmental correlations

• real duty cycles

• wireless performance in real locations

• degradation over time

• user interaction errors

This real world insight not only confirms product reliability but also guides future improvements in design, architecture and component selection.

Real world testing must start early

Many companies postpone real world testing until late in development, which often results in expensive redesigns. Instead, real world testing should begin as soon as the first prototype is stable enough to survive initial stress.

Testing early allows teams to correct structural weaknesses before they become costly.

Test early. Test repeatedly. Test in environments that resemble actual use.

Conclusion

Laboratory testing proves functionality. Real world testing proves survivability. Embedded devices face vibration, humidity, temperature swings, power noise, mechanical shocks and a wide range of unpredictable field conditions. They must be validated in environments that reflect reality, not laboratory perfection.

The companies that invest in comprehensive real world testing build products that last. Those that skip it face warranty claims, customer dissatisfaction and long term maintenance problems.

At Detus, we help teams design and validate hardware and firmware systems that remain stable under real world conditions, ensuring that products perform reliably where it truly matters.