Joints

Use the Joints tool to connect parts together while allowing movement at the joint location.

Click the satellite icon that appears when you hover over the Joints tool to view a list of all joints in your model.

Create a Joint

Detect features where a joint can be created, select what type of joint to create, then click Apply.

On the Structures or Motion ribbon, select the Joints tool.

Tip: To find and open a tool, press Ctrl+F. For more information, see Find and Search for Tools.
On the guide bar, choose to search All Parts in the model, or Select Parts to search for joints only between the parts you click.
Filter the search results.
- Select All on the guide bar to intelligently find features where a joint can be placed.
- Select a different option to filter for a specific type of feature, such as aligned holes or cylindrical pairs.
- Use the menu to refine your search criteria.
Click the Find button.
- If you chose the All Parts method, after you click Find, detected features will display in red.
- If you chose the Select Parts method, you must select at least two adjacent parts. Detected features between the parts you select will display in red.
  Note: When using the Select Parts method, features are automatically detected as you click through the parts in the model, so the Find button is greyed out to start. The Find button is needed only if detected features are cleared using the Reset button. Clicking Find will re-detect the previously detected features.
Select what type of joint to create (see Joint Types and States).
- Select Auto to automatically determine the best type of joint to place at each feature location.
- Select a different option to create a specific type of joint for all of the selected features. Options vary based on what was selected in the previous step.
Click the Apply button on the guide bar to automatically create joints in all of the selected (red) features, or left-click selected (red) features to create joints individually.

Select a joint to edit it.

The microdialog appears.

Joint editing options are listed below:


To	Do this	Notes
Change the joint's type	In the microdialog, select a joint type from the dropdown menu.	The joint can be changed to any type regardless of the type of joint Inspire creates based on detected geometry.
Translate or rotate the joint	In the microdialog, select the Move tool . Drag the white arrows, or enter a value for X, Y, or Z to translate or rotate the joint.
Reset the joint to its original location and orientation	In the microdialog, select the Reset button.	The joint type will not reset.
Resize the joint	While in the Joints edit context, click on the joint. Left-click, hold, and drag the white arrow,or enter a value for the Graphic Scale. Click in clear space to exit graphic sizing and enter normal editing mode.
Resize multiple joints	Hold the Ctrl key Select multiple joints. Enter a value in the Graphic Scale microdialog. The joints will be simoltaneosly resized.
Auto-fit the joint	In the Joints edit context, click on the joint, then click the white arrow. Click in the microdialog.

Right-click and mouse through the check mark to exit, or double-right-click.

Tip:

Joint types include grounded pin and grounded sliding pin. Grounded joints appear under Load Cases in the Model Browser, instead of under Connectors.
A common reason why joints aren't found is because the geometry isn't touching. Turn off the Auto search distance in the Find Options and enter a search distance manually.
If the Find operation does not detect all of the features you expected to see, try increasing the Search Tolerance in the Find Options.
If you already have a joint defined, but don't see the joint types you expected in the Joints microdialog or table, try adjusting the Search Distance in the Joints table.
To automatically detect relevant features when the tool is opened, go to the Preferences under Inspire > Geometry and turn on Autofind.
To connect a part to ground, you may want to use the Supports tool.
The name of a joint in the Model Browser also displays its type in parentheses, or its state if free or locked; only the name is editable.
Suppress/Unsuppress a joint to understand its effect on your model. On the joint, right-click and select Suppress. From the Model Browser or Table, right-click and select Unsuppress.

Find Options

Click the menu on the guide bar to filter the search results.

Find Larger/Smaller/Similar: Find holes that are smaller, larger, or similar (±5%) in size to selected holes.
Options: Click to specify options for the find operation.
Size: Specify a minimum and maximum size range for the hole diameter. This option applies to Aligned Holes and Single Holes. Click the icon to reset the default value.
Find Parts in Holes: If enabled, the Joints tool automatically finds existing geometry in holes, hides it, and deactivates it so that it is not included in analysis or optimization calculations. Deselect Find Parts in Holes to disable this behavior, in which case you will need to delete the existing geometry manually.
Find Blind Holes: Enable to automatically detect blind holes during the find operation.

Auto Search Distance: This is a global search threshold that uses default tolerances to find locations where joints can be created. When the checkbox is enabled, it is calculated automatically. To change the search distance, deselect the checkbox and enter a value in the text box. Any joints with a minimum gap less than the entered search distance will be found. (The minimum gap is the exact minimum distance between the two parts.)

Microdialog Options

Use the options in the microdialog to change the joint type and how it is constrained.

Joint Type

Joints are available in a variety of types such as Pin, Hinge, or Ball and Socket. The most likely joint type, which is based on the detected features, will be automatically selected. The joint type can then be changed to any type you would like.

Joint State

Each joint has a state which can be set to Locked, Active, or Free.

Select Locked to prevent movement in the joint.
Select Free if you want the mechanism to behave as if the joint is not there.

Move Tool

Select

to open the move tool for the joint. Translate or rotate the joint using the white arrows, or by entering a value for X, Y, or Z.

Reset

Select

to reset the joint to its original location and orientation.

Note: Refer to Joint Types and States for more information.

Joint Properties

Refine the behavior and appearance of joints using the joint properties available in the Property Editor (F3).

Connection Stiffness: Change how connection stiffness is defined for grounded joints (for structures analysis only).
Flip Part Order: Change the order of two parts in a given joint. This is useful when you want to invert a curve (such as action forces vs. reaction forces).
Behavior: Define joints as rigid, flexible, or virtual. Virtual is an expert option that is very similar to a rigid joint, but with "soft constraint" behavior that is useful for avoiding redundant joints. Default uses the global setting from the Run Motion Analysis window.
Friction for Motion: For rigid or virtual joints you can apply joint friction, which enables additional properties.
Motion Rates: For flexible joints, there are options for specifying Global, Basic, and Advanced motion rates. The Advanced option allows you to specify independent stiffness and damping rates for the degrees of freedom of the joint, as well as the angle of the local reference frame used by the flexible joint. The angle can also be set using a graphical manipulator in the Joints tool.
Note: When you change the default motion rate values to make a joint more flexible, it is likely that you will need to increase the Deformation Allowed setting in the Run Motion Analysis Settings window.
Figure 2. Joints tool angle manipulator for flexible joints (advanced rate specification)

Note: Alignment Snapping to Edge for Flexible Joints: The angle manipulator tool enables the x-axis to be easily aligned with another arbitrary edge in the motion model. As you drag the manipulator over an edge, the orientation of the x-axis snaps into alignment with the edge, and positive (or negative) direction is controlled via proximity along the edge. For your convenience, edge-snapping also works when you are aligning the arms on torsion springs.

Joints Table

The Joints table lists all of the joints in your model including the type of connection, the parts it connects, and the assigned material.

Click the satellite icon on the Joints tool to display the table.

The table data can be edited with the following actions:


To	Do this
Rename a joint	Select the cell in the table and then click again to make the field editable.
Change the connection type, state, material, or behavior	Select the cell in the table and then select a different option from the list.
Sort a column	Click the column header. Click repeatedly to toggle between ascending and descending order.
Add or remove columns	Right-click on a column header.

Note: The Search Distance listed in the Joints table shows the minimum separation (the exact minimum distance between the two parts). The search distance for an individual joint defined in this table will override the global search distance defined in the Find Options on the guide bar. The search distance is ignored when the Detected Feature type is aligned holes or single holes.

Shortcuts


To	Do this
Add a hole to the selection	Hold down the Ctrl key and left-click an unselected hole. The hole turns red.
Deselect a hole	Hold down the Ctrl key and left-click a selected hole.
Create a joint	Left-click a selected (red) feature or hole.
Isolate a joint	Press I to zoom in on the selected joint and its dependent parts. This works from the modeling window, Model Browser, and the Joints table.
Exit the tool	Right-click and mouse through the check mark to exit, or double-right-click.