If a belt assembly in your product undergoes primarily 2D behavior, learn a faster way to simulate it using the 2D belt option of the RecurDyn/Belt toolkit. A second benefit of this option is that long belts with thousands of segments can be solved efficiently. The commands of the 2D Belt are found within the 2D Belt group of the Belt tab.

The belt segments types that are useful for the 2D Belt system are the Flat Belt and Timing Belt. The 2D Belt simulation does not consider motion in the depth direction. Therefore it is not meaningful to use V-Belt and Ribbed V-Belt types because the side contact that is critical to their behavior is not considered. For this reason the V-Belt & Ribbed V-Belt are not supported in the 2D belt system.

In the past the belt system could not use a Guide body (sliding contact), instead only rollers could be used to guide the belt. However, conveyer systems or even the handrail on an escalator features belts that are guided by sliding contact. Therefore linear and arc guide bodies were added to RecurDyn to provide the needed sliding contact.

The linear guide is built by specifying two or more points that are used to define a series of flat contact surfaces. The user interface is shown below. The contact normal should be set to point out toward the belt location relative to the guide.

One arc guide body is composed of one or several arc geometry segments. So, you have to input the multi-points for the multi-arc geometry when you create the arc guide body. The contact normal of the arc guide is automatically set to be in the direction that is away from the center point of the arc (convex contact only). You can change the sign of the arc radius (R in the dialog box below) in order to change the direction of the contact normal.

Please note that if you create the arc guide with multiple points that it is not easy to confirm which direction is normal. The correct normal direction is defined as explained in the images below. You can confirm the direction of the contact using the preview button and adjust the sign of the radius value as appropriate.

The 2D Belt is always assembled within an X-Y plane. Directions for the 2D belt assembly are included in the images below.

You can download one or all of the following examples for more practice using the 2D Belt module.

• Escalator Handrail Model
• Escalator Handrail Model Final
• Escalator Handrail Model Roller Assembly

If you would like to trial the RecurDyn Belt Toolkit, please contact MotionPort.