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Robin | Mechanical Engineer
Robin | Mechanical Engineer

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Vibration Testing Is a Control Problem, Not Just a Power Problem

Shake It, Shock It — Prove It Survives.

Everything that flies, drives or ships gets shaken — by a launch, a runway, a road or an engine bay — and whatever is going to rattle loose, crack or fail is going to do it there, in service, where it's expensive and sometimes catastrophic. Neometrix's vibration & shock test system brings that environment into the lab, turns it up, and finds the weakness on the shaker instead of in the field. It's an electrodynamic shaker with amplifier and closed-loop controller, slip table and head expander, running random, sine, shock and shock-response-spectrum profiles to MIL-STD-810, IEC 60068 and ECSS — with a combined vibration-plus-climatic option for HALT/HASS testing.

Real Environments Are Random, Not Neat Sine Waves

A launch or a truck ride shakes a product across a whole frequency spectrum at once, not as one clean, swept tone. A real test has to reproduce that measured spectrum — a power spectral density profile — under closed-loop control, rather than the simplified single-frequency sweep that used to pass for a vibration test. That distinction is the core of what actually makes a qualification test valid.

It's a Control Problem as Much as a Power Problem

The shaker and amplifier are the muscle. The vibration controller — closing the loop against accelerometers to match the reference spectrum and hold the level — is the brain. Get the control loop wrong and you either over-test (breaking a genuinely good unit) or under-test (passing a genuinely bad one). Both failure modes defeat the entire purpose of qualification testing.

The Fixture Can Lie

The specimen has to see the true motion the test intends to deliver; a poorly designed fixture adds its own resonances and distorts the result — either inventing a failure that would never happen in the real world, or masking one that would. Slip tables, head expanders and rigid, characterised fixtures are part of the core engineering here, not an afterthought bolted on after the shaker is chosen.

The Environment, Completed

Vibration and shock is the dynamics member of the same environmental-qualification family as Neometrix's climatic chambers, EMI/EMC laboratory and thermal-vacuum chamber — temperature, electromagnetics, space and now dynamics, together forming the full qualification suite a serious test facility needs.

What Single Tests Miss

Mount the shaker to a climatic chamber and you get vibration at temperature — HALT/HASS — which precipitates failures that neither vibration testing nor temperature testing alone will ever find. The combined configuration is a distinct, genuinely valuable test capability, not a marketing bundle of two separate machines.

We Integrate; the Shaker Is Specialist

The electrodynamic shaker, amplifier and controller are bought-in specialist equipment. Neometrix engineers the system around them: the seismic-mass foundation, slip table, head expander, fixtures, the combined climatic option, safety and controls. No specific delivered system is claimed on this page — this describes a reference configuration engineered to order.

Frequently Asked Questions

Why does a modern vibration test use a random spectrum instead of a simple sine sweep?
Because real-world vibration environments — a launch, a road, an aircraft cabin — shake a product across many frequencies simultaneously, not as one clean tone swept through a range. A random power-spectral-density test reproduces that measured, realistic spectrum under closed-loop control, which is a far more faithful representation of what a product will actually experience than an old-style single-frequency sine sweep. Standards like MIL-STD-810 and IEC 60068 reflect that shift toward random-vibration testing as the primary qualification method.

What does HALT/HASS testing add that vibration testing alone doesn't catch?
HALT/HASS (Highly Accelerated Life Testing / Highly Accelerated Stress Screening) combines vibration with temperature and humidity cycling at the same time, typically by coupling a shaker to a climatic chamber. Some failure modes only show up under combined stress — a solder joint that survives vibration alone and temperature cycling alone can still fail when both are applied simultaneously, because the combined mechanical and thermal stress interacts in ways a single-stress test can't replicate. That's why a combined vibration-plus-climatic system is treated as a distinct, valuable test capability rather than simply running two separate tests back to back.

Get In Touch

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