I suggest you check the 01dB orchestra system
01dB, inc. ... 01dB Inc - 31 Jordan Street - P.0. Box 796 - Skaneateles, NY 13152 -
Phone # 315-685-3141 - Fax # 315- 685-3194www.01dbsupport.com/
Maybe you ought to take care of the dynamical effect due to the rotating inertia as weel.
I have seen cases where the modes shifted enough to tell you that everything is safe in static condition, and get a vibration issue when the machine is running.
To get enough force, you can as well use a...
As greg says : We have tried intensity with a accelerometer and mike close to it and it works.
Holography techniques are based on the acquiisition and separation of both active and recative fields, and are much more accurate in source localization that intensity or pressure.We happen to be...
To my knowledge the pure way to look at this is to say that the added mass of the accelerometer should not be more than 10% of the modal mass of the structure. To have the modal mass you have to perform a modal analysis and thus make measurements on the blade ... if you can do those measurements...
DSPT Siglab/Matlab platform are a good compromise for versatility at reduced costs but it comes with reduced stability as well...A lot of people have developped codes under the Matlab environment making similar things as what you can find on LMS (NPA)...I use it with STAR systems for modal or...
Well you will mainly see the scanning frequencies as greg sais, but this is assuming the control of the mirror provides pure sine motions.
If the scanning motions are more like sawtooth, then you will see many harmonics on a FFT (decomposition in sines).
If the motion involves shocks, as if for...
If the high axial level is at rotation frequency, you may have a blade poorly oriented resulting in axial loading at rotation frequency. ISO 2372 / BS 4675 can be helpful for limits.
Dmitry,
If you aretalking about free response, the modal characteristics, i.e. natural frequency, deformed shape and associated modal damping depends only on the dimensions, material properties and boundary conditions of the beam in the case of a linear system.
Maybe a simple way to handle...
Dave,
What is exactly the problem you are facing ?
Sound intensity is helpful in noisy environment to quantify and localize sources.
You can send info to : thomas.antoine@metravib.fr
www.metravib.fr
Dmitry,
You shall not consider the total mass of the structure, but the modal mass,i.e. the amount of material that "moves" at the mode you are considering.
Typically, the mass of your measuring equipement,i.e. accelerometer, or in your case modal mass of the hammer shall not exceed...