Space Qualification — Tool

Shaker sizing

Before a vibration test is booked, someone has to check the shaker can actually do it. Force equals the total moving mass times the acceleration — and the total includes everything bolted to the armature, not just the unit under test.

F = (m_EUT + m_fixture + m_armature) · a · k_margin

Inputs

EUT mass (kg)

Fixture mass (kg)Head expanders count too. Fixtures are often heavier than the EUT.

Armature mass (kg)From the shaker datasheet — the moving element itself.

Test level (g)Peak sine level, or ~3× gRMS for random as a working rule.

Margin factorHeadroom for control overshoot, notching studies and reality.

Result

Required force—

In pounds-force—

Moving mass total—

Without margin—

Shaker ratings differ between sine, random and shock — check the required force against the correct column of the datasheet. For random tests the rating is usually quoted in force RMS; the 3× rule of thumb here is planning guidance, not a substitute for the control-system prediction.