Register to reply

Mechanical vibration and shock control

by sri.karmarkar
Tags: control, mechanical, shock, vibration
Share this thread:
sri.karmarkar
#1
Sep8-08, 04:11 AM
P: 9
Please could anyone help me on the topic "Controlling the vibration and shocks received by elctronic-mechanical components"?
Phys.Org News Partner Engineering news on Phys.org
New filter technology uses inert gas to bore holes in high-quality steel
Augmented reality helps in industrial troubleshooting
How wireless technology can dramatically improve ship safety
FredGarvin
#2
Sep8-08, 06:36 AM
Sci Advisor
FredGarvin's Avatar
P: 5,095
Sure. Take a year or two of college classes and then learn more under a mentor in the field.

Can you be a bit more specific with your request?
sri.karmarkar
#3
Sep8-08, 08:07 PM
P: 9
Thank you fred for your reply and suggestions.

I will start learning on the topic and will be enquiring where i get strucked. I will try to mention the topic more specific.

The first query from me
"What is natural frequency and how it can be obtained or estimated?".

FredGarvin
#4
Sep8-08, 09:05 PM
Sci Advisor
FredGarvin's Avatar
P: 5,095
Mechanical vibration and shock control

The natural frequency is a vibration mode that is inherent to all structures. It is the frequency that the structure will vibrate at if the body is given a single impulse. In other words, it is the frequency that the body will vibrate at on its own, without an external forcing of any kind other than an initial "push."

Natural frequencies are calculated as well as measured through various techniques such as modal analysis.
sri.karmarkar
#5
Sep8-08, 09:14 PM
P: 9
Thanks fred.
Where can i get an example of calculating the natural frequency by modal analysis?
Please help me. Any links so that i can get a clear picture on this?
rbeale98
#6
Sep8-08, 10:34 PM
P: 52
try this
http://cp.literature.agilent.com/lit...5954-7957E.pdf
sri.karmarkar
#7
Sep8-08, 10:45 PM
P: 9
Thank you so much rb.. let me go through this.
sri.karmarkar
#8
Sep8-08, 11:47 PM
P: 9
How the materials fails when it is subjected to excitation?
what are the influencing factors?
Material fails is it because of lone factor "excitation frequncy reaches more than the natural frequency?".
FredGarvin
#9
Sep9-08, 06:50 AM
Sci Advisor
FredGarvin's Avatar
P: 5,095
The influencing factors are the basics of fatigue and strength of materials. If you excite a structure's natural frequency, it can take no time at all for that structure to reach its fatigue life. It gets amplified by the fact that the alternating stresses can be quite a bit higher than one would expect at any other operating point. Take a look at a basic S-N diagram to get an idea about this.

Quote Quote by "sri.karmarkar
Material fails is it because of lone factor "excitation frequncy reaches more than the natural frequency?".
The point to be worried about is when the excitation frequency matches the natural frequency. If you are above or below it, you shouldn't need to worry about it. Even if you do reach the natural frequency, sometimes it's not a big deal due to the design or the system's ability to dmpen vibrations. Still if you are close to the natural frequency, you need to know what the result will be. You can't ignore it. This is why we do things like shaker and modal testing.


Register to reply

Related Discussions
Dimmer or router speed control as resistance heater level control Electrical Engineering 11
A mechanical engineering student hating mechanical design Academic Guidance 14
Is every mechanical process or mechanical reversible? Mechanical Engineering 4
Physics of a Vibration Dampener (Tennis shock absorber) General Physics 1
Can you shock someone?y Electrical Engineering 17