Vibration Testing
Vibration Testing
(OP)
Has anyone temporarily installed equipmnet in an aircraft for vibration testing? I need to test the vibration a piece of equipment is subjected to inside the radome comopartment. I am looking for a list of test equipment (ie. 2 single axis accelerometers, one tri-axis accelerometer , power supplies, signal conditioners, and data logger) for a temporary installation. Battery operated devices are the optimum solution, but I can tap into the aircraft power if necessary.





RE: Vibration Testing
RE: Vibration Testing
RE: Vibration Testing
RE: Vibration Testing
RE: Vibration Testing
I suggest that you need to breakdown your testing into smaller chunks.
1. What is the maximum vibration level that the equipment can operate at without degraded performance?
2. Is the equipment subjected to vibration in excess of that level while in flight.
I still suggest ground based testing for step 1. Aerodynamic forces can be simulated if necessary.
RE: Vibration Testing
I am just looking for test setup/equipment info, at this time.
RE: Vibration Testing
If you are in the USA talk to Endevco, in Europe talk to B&K. They can help you select the instrumentation, and may be able to give you advice on where to stick the acceleromenters. Given that flight time is usually expensive you'll probably want some redundancy.
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: Vibration Testing
To identify the frequency components of the vibration then some kind of FFT system is needed in your analysis so do you carry a real time analyser on-board or record the data for ground replay. If you record the data then look closely at the requirements of the analysis system in terms of bandwidth, sample size, dynamic range and anti aliasing.
RE: Vibration Testing
You state that you are attempting to isolate the problem to either the mounts or the equipment. However they are a dependant system. Measurement of the response of the system does not allow you to draw any meaninful conclusions about the response of either component of the system without detailed knowledge of the vibration response of the other component.
Calculating transfer functions and coherence of each acclerometer against every other accelerometer and the "driving" vibrations might theroetically yield some information, but culling out the non-meaningful data is exceedingly non-trivial.
Serioulsy, ground based shaker table is the way to get started.