Create Virtual Joints

Connect faces/spots that can have relative motion in the form of displacements and/or rotations.

  1. In the Project Tree, click on the Connections branch to open the Connections workbench.
  2. On the Connections workbench, select > Joints.
  3. Create one of the following types of joints:
    Type Process
    Ball
    		 A ball joint allows free rotations in any direction about the joint center, while the translations are fully constrained.
    1. In the dialog, select the Ball radio button.
    2. Use the radio buttons to apply to either Faces or Spots.
      Note: If applying to Spots, you can choose to Create new spot.
    3. Specify the Joint center in the X, Y, and Z fields.
    Hinge


    		 A hinge joint only allows rotations about the joint axis. The axis is defined by the joint center and a vector.
    1. In the dialog, select the Hinge radio button.
    2. Use the radio buttons to apply to either Faces or Spots.
      Note: If applying to Spots, you can choose to Create new spot.
    3. Specify the Joint center in the X, Y, and Z fields.
    4. Specify the Joint axis in the X, Y, and Z fields.
    Cylinder
    		 A cylindrical joint allows rotations about the joint axis and sliding along the axis. The axis is defined by the joint center and a vector.
    1. In the dialog, select the Cylinder radio button.
    2. Use the radio buttons to apply to either Faces or Spots.
      Note: If applying to Spots, you can choose to Create new spot.
    3. In the modeling window, select where to apply the joint.
    4. Specify the Joint center in the X, Y, and Z fields.
    5. Specify the Joint axis in the X, Y, and Z fields.
    Linear Guide


    		 A linear guide joint only allows sliding along the joint axis. The axis is defined by the joint center and a vector.
    1. In the dialog, select the Linear guide radio button.
    2. Use the radio buttons to apply to either Faces or Spots.
      Note: If applying to Spots, you can choose to Create new spot.
    3. In the modeling window, select where to apply the joint.
    4. Specify the Joint center in the X, Y, and Z fields.
    5. Specify the Joint axis in the X, Y, and Z fields.
    Universal

    A universal joint allows rotary motion transmission between two shafts which are at an angle to each other and which have intersecting axes. The joint works as a ball joint but makes dependent shaft rotations about their axes. This joint requires definition of a joint center and axis of the both the shafts connected.

    1. In the dialog, select the Universal radio button.
    2. Use the radio buttons to apply to either Faces or Spots.
      Note: If applying to Spots, you can choose to Create new spot.
    3. In the modeling window, select where to apply the joint.
    4. Specify the Joint center in the X, Y, and Z fields.
    5. Use the radio buttons to specify Joint axes data for Axis 1 and Axis 2.
    Flexible Shaft

    A flexible shaft allows complete rotary motion transmission between the two shafts. The joint works by constraining the rotations about the shaft axes. This joint requires definition of flexible-shaft end coordinates and respective shaft axes.

    1. In the dialog, select the Flexible shaft radio button.
    2. Use the radio buttons to apply to either Faces or Spots.
      Note: If applying to Spots, you can choose to Create new spot.
    3. In the modeling window, select where to apply the joint.
    4. Use the radio buttons to specify Flexible shaft data for End 1 and End 2 coordinates.
    Note: In the joint images, red arrows indicate constrained movement and green arrows indicate free movement.
    Note: Virtual connectors create perfectly rigid boundaries, stresses along the boundary faces can have local concentrations. It is recommended to create joints between parts locally using spots.
    Note: Depending on the type of joint/face picked, the joint axis is automatically oriented either along the axis of the face or normal to the face.
    Note: In most cases, the joint center coordinates are automatically populated by calculating the c.o.g. of the picked faces/spots. In case of universal joint, the joint center coordinates are obtained by intersecting the two axes.
  4. Click OK.