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.
  2. On the Connections workbench, select > Joints.
  3. In the Virtual connector dialog, 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. 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. The joint center is set in COG by default. To change the joint center, uncheck the Set in COG checkbox and specify values for the X, Y, and Z coordinates.
    Hinge


    		 A hinge joint only allows rotations about the joint axis. The axis is defined by the joint center and a vector.
    1. 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. The joint center is set in COG by default. To change the joint center, uncheck the Set in COG checkbox and specify values for the X, Y, and Z coordinates.
    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. 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. The joint center is set in COG by default. To change the joint center, uncheck the Set in COG checkbox and specify values for the X, Y, and Z coordinates.
    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. 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. The joint center is set in COG by default. To change the joint center, uncheck the Set in COG checkbox and specify values for the X, Y, and Z coordinates.
    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. 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. The joint center is set in COG by default. To change the joint center, uncheck the Set in COG checkbox and specify values for the X, Y, and Z coordinates.
    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. 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: Joints 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.
  4. Click OK.