hexagon logo
Register Sign in
  • State Not Answered
  • Replies 7 replies
  • Subscribers 11 subscribers
  • Views 65 views
  • Users 0 members are here
Options
Related

What is the difference between Primitives and General constraint?

vaibhavd
I was reading one old ADAMS tutorial where the instructor used General constraints. At that time inline primitives option was not available. Now both options are available in the new version. It makes me confused to differentiate between them. Kindly share your knowledge on the same.
 
Parents
  • 0
    Looking at that example, I see a few things that is suspicious from a modeling practice stand point.
    First, the GCON is not used instead of an inline jprim but instead of an inplane jprim. THis is because it uses the function DY(m1,m2,m2) that defines a plane, not a line.
    Second, and this is a big no-no in general model building: Do not use the CM marker for anything else than defining center of mass location and eventually the inertia axis. If you start doing this, sooner or later you build a model where the mass and inertias are auto-calculated by Adams. You define a function involving the cm-marker and then do some small change to the geometry which now breaks the intended function of the model as Adams would have moved and reoriented the cm-marker. These are some of the hardest problems there is to debug. So don't do it.
     
Reply
  • 0
    Looking at that example, I see a few things that is suspicious from a modeling practice stand point.
    First, the GCON is not used instead of an inline jprim but instead of an inplane jprim. THis is because it uses the function DY(m1,m2,m2) that defines a plane, not a line.
    Second, and this is a big no-no in general model building: Do not use the CM marker for anything else than defining center of mass location and eventually the inertia axis. If you start doing this, sooner or later you build a model where the mass and inertias are auto-calculated by Adams. You define a function involving the cm-marker and then do some small change to the geometry which now breaks the intended function of the model as Adams would have moved and reoriented the cm-marker. These are some of the hardest problems there is to debug. So don't do it.
     
Children
No Data
© 2025 Hexagon AB and/or its subsidiaries. Privacy Policy | Cloud Services Agreement