27.3.1. Modeling Options

  1. Click the Assembly icon of the Assembly group in the Track(HM) tab and select a set of bodies with which the track chain makes contacts.

  2. Whenever the user moves the mouse, the underling body is highlighted and the user sees the solid line connecting the previously selected body and the highlighted body. After making a closed chain, the following dialog box for the track chain pops up.

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    Figure 27.47 Track assembly

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    Figure 27.48 Assembly dialog box

  3. Enter the number of track links and click Estimation. A user can compute approximately pre-tension between track links from an estimated track gap.

  4. Click OK, then the Track assembly is completed.

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    Figure 27.49 Track assembly

27.3.1.1. Assembly dialog box

During assembly, a below dialog box is shown.

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Figure 27.50 Assembly dialog box

  • Passing Bodies: Shows the list of assembled bodies.

  • Sprocket Modification: Modifies the assembly information about Sprocket. For more information, click here.

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    Figure 27.51 Sprocket Assembly Information dialog box

  • Link: Selects a clone link. If the user clicks Set, the user can customize the generated link set.

    • Set: The user can use link sets wanted among the defined link sets. To use this function, the user must define link sets when creating clone of a link. For more information, click here.

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    Figure 27.52 Link Set Customization dialog box

    • Link Set Customization

      • The user cannot move the first link and can compose user’s link by the database’s link.

      • The composed link set is marked in the RMD file.

  • Estimation: The user can estimate the assembled links.

    • Auto Link No. Calculation: If the user clicks Estimation with the checked this option, the number of links is set automatically.

    • Number of Links: Modifies the number of links.

    • Pin Gap: Shows a value of pin gap.

  • Automatic Sprocket Alignment: If this option is checked, the sprockets are rotated to match the position of the links.

    Note

    If there are interference between a sprocket and a link after finishing assembly with this option, the alignment is failed.

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    Figure 27.53 After using Automatic Sprocket Alignment option

Tip

The track link pins and sprocket tooth must be initially engaged properly. Too much of initial penetration of the link pins into the sprocket tooth often results in a simulation failure. Therefore, the sprocket must be rotated by using object control so that the initial penetration between the link pin and sprocket remains to be small. If the sprocket is rotated after attaching the revolute joint between the sprocket and the chassis, the initial condition or motion expression must be modified accordingly.
Contacts of the track chain are defined between track links and only inside bodies of a track chain system.