×
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!

*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

Mesured Acceleration as Input to ADAMS

Mesured Acceleration as Input to ADAMS

Mesured Acceleration as Input to ADAMS

(OP)
Dear Forum,

I have 5 sets of Data representing x,y,z acceleration at
Point  _A and y,Z accelerations at Point_B.

Is there a way to use this data to simulate the reaction of a Mechanism to those Accelerations?

Thx
Martin
Replies continue below

Recommended for you

RE: Mesured Acceleration as Input to ADAMS

Yes. You can either build a spline with them, and use that as an excitation, or you can read in the file. The latter sounds more straightforward, but it is not immediately obvious how to do it.

You may have to double integrate them first, to give displacements.

Here's the relevant part of the adm file where I applied a time history of force to a model

!                           adams_view_name='SFORCE_1'
Sforce/1
, Translational
, I = 67
, J = 68
, Actiononly
, Function = INTERP(time,1,1)
!
!------------------------------ DATA STRUCTURES --------------------------------
!
!                           adams_view_name='SPLINE_1'
!                           adams_view_units='no_units'
Spline/1
, File = /simple/shudderwft.rsp
, Channel = 6
!
!                        adams_view_name='SFORCE_1_MEA_1'
Variable/1
, Function = SFORCE(1,0,1,0)
!
!                        adams_view_name='SFORCE_1_MEA_2'
Variable/2
, Function = SFORCE(1,0,2,0)


you'll be able to do the same with a MOTION statement.


Cheers

Greg Locock

RE: Mesured Acceleration as Input to ADAMS

(OP)
Hi Greg,

thx for your reply!

But I'm still a little *g* bit lost.

Duoble integrating the data is VERRY errorenous.
and as I'm quite new to this game what is an adm file what do I do with it where does it integrate into the simulation ...

I started out with Dynamic Designer but was able to persuade the company to go for the full range. Now I got the toy, but I'm overhelmed by it's possibilties.

Sorry to bother you or anybody else who is willing to support a bloody rooky.

cheers

Martin


and by the way forgive me my english.

RE: Mesured Acceleration as Input to ADAMS

Which package are you using?

Double integrating is not erroneous, you are going to trust ADAMS to do it anyway! However according to this velocity is better.

http://support.adams.com/kb/faq.asp?ID=kb9752.html

Note that you can only apply a MOTION to a joint.

Have you done all the ADAMS/View tutorials? You need to.

The adm file is a list of all the model statements that gets sent to the Solver. As such it is very good debugging tool, for the more integrated products, which do not explicitly create an adm file.


As a first step do the following tutorial

http://support.adams.com/kb/faq.asp?ID=kb8708.html

then convert it so that the slider motion is defined by one of your drive files.

Cheers

Greg Locock

RE: Mesured Acceleration as Input to ADAMS

(OP)
Hi Greg,

thx for your advise!

I'm almost there

Martin

RE: Mesured Acceleration as Input to ADAMS

Greg I'm sure you can add an acceleration directly to a joint. In the general motion dialog box you can select the function to be an acceleration as a function of time and you can do it directly in command language using something like this:

var set var=.EH101_MMI_AC.MOTION_deck.t1_type int=3

Ben

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! Already a Member? Login



News


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close