point mobility analysis

[nlb76]

Dear friends,
I am trying to do a point mobility analysis on a chassis frame of truck. I have given excitations with unit magnitude and recorded velocity response as output. I am completely new to ths type of analysis. Can anyone please guide me, what are the next steps in further evaluation and improvement point of view.

Nitin

 

[GregLocock]

So, you have a transfer function of mms/s/N, vs frequency?

If not, that is your next step.

Now you need to decide on an appropriate limit for each frequency.

Then you identify where you exceed that limit.

Then the hard bit starts.



Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[nlb76]

Thanks Gerg. Yes, I have transfer function data. My truck engine's idle frequency is 53.3Hz.(corresponding to 800rpm and 8 cylinder.) For this engine max rpm is 5000. Corresponding to 5000 rpm, frequency comes to be 333.33Hz. I really didn't know, whether to check the V/F response near 53.3Hz freq OR I need to check V/F response for whole operating freq range. Can you please throw some more light on the above issue.

 

[GregLocock]

The whole lot, although pay especial care to idle and max torque and the red line.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[nlb76]

Thanks Greg. I will go ahead with your guidelines.