contact modify

2. For sphere-to-sphere and cylinder-to cylinder contacts, you can specify whether the contact should be inside or outside the sphere or cylinder.

3. In general, the higher the stiffness, the more rigid or hard are the bodies in contact. Also note that the higher the stiffness, the harder it is for an integrator to solve through the contact event.

4. Parameter dmax defines the penetration at which Adams Solver turns on full damping. Adams Solver uses a cubic STEP function to increase the damping coefficient from zero, at zero penetration, to full damping when the penetration is dmax. A reasonable value for this parameter is 0.01 mm. For more information, refer to the IMPACT function.

5. Adams Solver (FORTRAN) models normal force as a nonlinear spring-damper. If PEN is the instantaneous penetration between the contacting geometry, Adams Solver calculates the contribution of the material stiffness to the instantaneous normal forces as STIFFNESS * (PENALTY)**EXPONENT. For more information, see the IMPACT function. Exponent should normally be set to 1.5 or higher.

6. A large value of PENALTY ensures that the penetration, of one geometry into another, will be small. Large values, however, will cause numerical integration difficulties. A value of 1E6 is appropriate for systems modeled in Kg-mm-sec. For more information on how to specify this value, see Extended Definition. Range: PENALTY > 0

7. A value of zero for the restitution_coefficient specifies a perfectly plastic contact between the two colliding bodies. A value of one specifies a perfectly elastic contact. There is no energy loss. The coefficient of restitution is a function of the two materials that are coming into contact. For information on material types versus commonly used values of the coefficient of restitution, see the Material Contact Properties table.

8. The augmented_lagrangian_formulation parameter uses iterative refinement to ensure that penetration between the geometries is minimal. It also ensures that the normal force magnitude is relatively insensitive to the penalty or stiffness used to model the local material compliance effects. You can use this formulation only with the POISSON model for normal force.

9. The friction model in CONTACT models dynamic friction but not stiction. The argument values, on/off/dynamics_only, specify at run time whether the friction effects are to be included.

10. For information on material types versus commonly used values of the coefficient of static friction, see the Material Contact Properties table. Excessively large values of mu_static can cause integration difficulties.

11. For information on material types versus commonly used values of the coefficient of the dynamic coefficient of friction, see the Material Contact Properties table. Excessively large values of mu_dynamic can cause integration difficulties.

12. Adams Solver gradually transitions the coefficient of friction from mu_static to mu_dynamic as the slip velocity at the contact point increases. When the slip velocity is equal to the value specified for friction_transition_velocity, the effective coefficient of friction is set to mu_dynamic. For more details, see Extended Definition.

13. Specifying i_flex and j_flex parameters for Adams Solver (FORTRAN) will result in a warning message that the created contact is no longer compatible with the solver.

14. i_edge and j_edge are the matrices consisting of the nodes of the free edges identified by the edge index. You have to first, select a flexible body and then you will be asked to pick one of the free edges generated (more than one free edge can exists) on the flexible body.

15. edge_index is an optional parameter. If you do not specify, it will be calculated internally.

16. If contact_type "solid-to-solid" is specified and the geometry supplied is capable of analytical contact detection then Adams will automatically treat them analytically. See the Adams Solver CONTACT statement documentation for details on which types of geometry are treated analytically.

17. Solid-to-solid contact is limited to external contact surfaces. So, to take advantage of analytical contact detection for sphere or cylinder geometry and use an internal surface for contact one must specify type = sphere_to_sphere or cylinder_to_cylinder.

18. Stiction property can be ON only when contact type Solid-to-solid, penalty and restitution_coefficient is not set, i_geometry_name and j_geometry_name is not Sphere, Ellipsoid, Cylinder or Frustum or child of FE part. Stiction property is not supported for when Parasolid option is selected for Geometry Library.