×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Animating complex shapes

Animating complex shapes

Animating complex shapes

(OP)
Hello,

I don't know if this is the right forum for this.

I would like to animate some mode shapes, at the moment I have  written my program so that it uses cos(real part of mode shape) + sin(imaginary part of the mode shape). This indeed produces a shape which seems correct, but when I compare my complex mode shapes to those in a commercial modal analysis program(mescope) the shape at 0 degrees( when  the shape should be entirely imaginary?) looks slightly different than mine, although using the same data.

Many thanks in advance

Harry

RE: Animating complex shapes

Hmmm what software are you using?

Tobalcane
"If you avoid failure, you also avoid success."

RE: Animating complex shapes

(OP)
I've written my own software. I'm comparing it against Vibrant technology's Mescope.

RE: Animating complex shapes

(OP)
Please ignore the formula in the first post, thats not what I've written, I didn`t have the code in front of me when I wrote my original post, my brain must need defragmenting.

My code goes as follows

degrees = 0 to 360 in 10 degree steps

real(mode shape) * cos(degrees) + imag(mode shape)*sin(degrees)


Many thanks

Harry

RE: Animating complex shapes

If you want to get the magnitude from Re and Im data, you need to take the square root of the sum of the squares of the magnitudes.

RE: Animating complex shapes

... and the phase is arctan(Im/Re).

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources