Point to Deformable Surface Contact

A Point to Deformable Surface contact can be used to model contact between a point on a rigid body and a deformable surface. When the deformable surface is defined on a surface of flexible body, this entity can be used to model contact between a rigid body and a flexible body. The contact is specified at a certain radius from the point. As a result, the contact is essentially between a sphere represented analytically and a deformable surface.

Define the Connectivity of Point to Deformable Surface Contacts

From the Connectivity tab, you can resolve the required references for the point to deformable surface contact entity.

  1. If the Contacts panel is not currently displayed, select the desired contact by clicking on it in the Model Browser or in the modeling window.
    The Contacts panel is automatically displayed.
  2. Click the Body collector and select the body that the sphere is going to be attached to from the modeling window, or double-click the collector to open the Model Tree (from which the desired body can be selected).
  3. Click the Point collector and select the point that will act as the center of the sphere from the modeling window or Model Tree.
  4. Click the Surface collector and select the deformable surface entity that will be contacting the sphere.

Define the Properties of Point to Deformable Surface Contacts

From the Properties tab, you can define the contact method and the properties for the option type selected.

  1. Click the Properties tab.
  2. Select the desired method and define the related properties.
    If Linear is chosen:
    1. Enter a value for the radius of the sphere that the deformable surface will be contacting.
    2. Enter a value for the stiffness of the contact force.
    3. Enter a value for the damping of the contact force.
    If Poisson is chosen:
    1. Enter a value for the radius of the sphere that the deformable surface will be contacting.
    2. Enter a value for the penalty parameter to determine the local stiffness properties between materials.
    3. Enter a value for the coefficient of restitution.
      This value represents the energy loss between the two contact bodies. The valid range for this value is between 0.0 and 1.0. A value of 1.0 represents no energy loss and a perfectly elastic contact. A value of 0.0 represents a perfectly plastic contact and all energy is dissipated during contact.
    If User-Defined is chosen:
    1. Enter a value for the radius of the sphere that the deformable surface will be contacting.
    2. Enter the user subroutine function expression in the in the User expr: text box.
    3. MotionSolve the Use local file and function name check box if the use of a local subroutine file is necessary.
    4. Select the subroutine file in the local system by clicking on the Local File: folder icon.
    5. From the Function Type drop-down menu, select the type of the subroutine file: DLL/SO, Python, or MATLAB.
    6. Enter the function name in the Function Name: text box.
      MotionView provides PTDSFSUB as the default, which is the default function used by MotionSolve and ADAMS.
Tip: For a 3D object, the normals point outward, which represents a typical outer surface of a volume. Click Flip normal to turn that surface into a void, or "hole".