NX Siemens simple motion CAD CAM profile Follower motion with 3D contact
How to apply contacts for 3D CAD model in Mx Siemens?
1. Choose Home tab→Contact group→3D Contact .
2. In the Type group, select the type of 3D contact you want to create.
3.
If you are creating a CAD Contact , do the following:
In the Action
group, click Select Body .
In the graphics window, select the first
solid body in the contact pair.
Note:
For the RecurDyn solver,
the action body must contain a link. In addition, select the body that has
more movement during the simulation. For example, if you are modeling contact
between a rolling wheel and a road surface, the wheel should be the action
body.
4. If you are creating a Sphere To CAD contact type, do the
following:
In the Sphere group, click Select Link .
In the
graphics window, select the sphere link in the contact pair.
Click
Specify Point .
5. In the graphics window, select the point that
will be constrained to maintain contact with the sphere.
In the
Base group (for CAD Contacts ) or Body group (for Sphere To CAD contacts),
click Select Body and then select the second body in the contact pair.
Note
For
Sphere To CAD contact types, the base body must contain a link.
For the RecurDyn solver, you should attempt to define the base body as
follows.
Select a fixed body (if available).
Select the
most-constrained body (that is, the body with the lowest number of
unconstrained degrees of freedom). The changes in the position and orientation
of the base body are less than the motion of the action body.
Select
the larger body. In dynamic analysis, the larger-mass geometry is generally
more stable.
For example, if a wheel is rolling on a road surface,
the road surface is typically the base body.
6. If you are using
the RecurDyn solver, in the Type list, select Solid .
Note
The
Faceted and Fitted methods are for backward compatibility only.
7.
In the Stiffness box, enter an appropriate stiffness value that reflects the
characteristics of the materials that are in contact.
For a given
application, you should use empirical data as a starting point. If you do not
have empirical data, you can start with the sample values provided in
Guidelines for contact materials. When troubleshooting the appropriate
stiffness to use, you should incrementally multiply or divide the value by
factors of 10.
A very large Stiffness value may result in slower
solve performance or solver lockup.
8. If you are using the
Simcenter Motion Solver, in the Max Penetration Depth box, enter a fixed value
that represents the depth of penetration at which the damping factor attains
the value specified in the Material Damping box.
This value varies
based on the scale of your model. For example, a defined contact in a
precision mechanism in a camera has a different penetration depth than a
contact between larger objects in a manufacturing assembly line. If the value
is too small, the damping force rises sharply at the onset of an impact event,
which can cause the solver to reduce the numerical integration step size,
increasing the solve time. If the value is too large, the actual damping
applied is insufficient.
9. On the Basic tab, specify the remaining
contact parameters as described in 3D Contact dialog box.
In most
cases, the default parameters on the Advanced tab are appropriate and do not
need to be changed. However, if the solution does not solve, solves very
slowly, or if the contact behavior is incorrect, see Troubleshooting RecurDyn
Solid 3D contacts or Troubleshooting Simcenter Motion Solver 3D contacts.
10.
In the Name box, type a unique name for the contact or accept the default
name.
11. Click OK .
Tip:
You can copy the
parameters from a 3D contact and paste them into another 3D contact. In the
Motion Navigator , right-click the contact and select Copy Parameters . Then,
right-click the target contact and select Paste Parameters .
How to create simple motion on CAM profile in Siemens Nx ?