Test fixture resonance. Prior to test, a test fixture survey should be conducted to ensure that the structural characteristics of the test fixture do not introduce uncontrollable resonances into the test setup. The survey may be experimental or analytical. If problematic resonances are identified, modifications should be made to the test fixture to shift the resonance beyond the frequency range of the test or to dampen the resonance in order to minimize the effect on the test.

Ideally, the vibration test fixture should be designed to be: first, as light as possible and second, as stiff as possible. But in the real vibration testing world, there are a lot of constraint that we need to consider and then we need to find and optimum point, that can balance all required aspects such as cost, timeline, etc.