Dynamic analysis of many mechanical systems is often involved with contacts among bodies or flexible bodies. To solve a contact problem of the flexible body, the nodal synthesis method is used to represent its local behavior in RecurDyn/FFlex. An external surface of the flexible body can get from a finite element model and the contact surface is approximated by either triangular or rectangular patches. The contact force can be calculated with a compliance contact model, and which one of the most known mathematical approximation of the dynamic behavior of a contact pair has been that a body penetrates the other body with a relative velocity at a contact point in a field of multi-body dynamics.
The Contact Forces in RecurDyn/FFlex are mainly divided into two classes.
•They are contacts with a flexible surface and a flexible curve.
•The cross section of the flexible curve is assumed to be a circle
•The flexible surface is approximated as a triangular or rectangular patch.
•The FFlex body is contacted with a rigid body or other FFlex body by using the following Contact Forces.
•Even though the contacted patch sets are within the same body, they are contacted.
Figure 1 Contact group in the Flexible tab
Steps to create
1. Create patch sets for each FFlex body.
2. Click two patch sets on the screen.
•The first patch set becomes the base contact surface.
•The second patch set defines as the action contact surface. In this case, the patch set should be generated from beam elements.