Knowledge Base

Article Number: 116 | VC6 | VC5 | VC4 | VC3 | Post Date: November 22, 2024 | Updated: November 22, 2024

Is it possible to place flexible post lane separators/delineators in my scene?

Yes, this is very easy to do in Virtual CRASH. The video below shows an example of such a flexible delineator system in action.

First, you will need to decide if you want the delineators to be static or dynamic objects. If dynamic, you will next need to decide if you want the delineator objects to be rigid bodies, thereby directly interacting with other rigid body objects (such as vehicles) via contact interactions, or if you want to drive their motion via a constrained motion time-controller, such as the diagram tool or by data animation control.

Creating Delineators

You are free of course to purchase a delineator object from a 3D mesh provider. In this case, we will simply construct one from a cylinder object. Here we start by making a simple cylinder (Create > Standard Primitives 3D > Cylinder). Our point cloud also includes the delineator, which can be used as a geometrical reference to set the cylinder’s dimensions.

An ellipsoid with black plastic PBR material is used to form a simple base for the delineator. A simple albedo texture is made for the white delineator with yellow reflective tape.

This is sufficient for a static delineator. For a dynamic delineator, continue reading below.

Motion by Simulated Contact InteractionS

To simulate a contact interaction between a vehicle and the delineator, you’ll first need to convert the (unfrozen) delineator mesh to a rigid body. It is recommended that the user pause physics (Create > Physics > Stop Simulation [Hotkey “P” for VC6 users]). Select the delineator, then left-click Create > Physics > Make Rigid Body from Selection. Next, go to the delineator’s “mass properties” menu, and set its weight as needed. Set the joint stiffness and damping as needed and ensure “fix orientation” is enabled.

Next, select the base and select Create > Physics > Make Unyielding / Terrain From Selection.

To connect the delineator mesh to the base, we use a spherical joint (other joints may also be used depending on your requirements). Select Create > Physics > Spherical Joint.

Hover your mouse cursor over the delineator hold+left-click and drag to the base and release. This will connect to two meshes together with the joint (learn more).

Select the joint and switch to “Parent Space”. Press [1] at the top of the keyboard and [F2] to reveal the translation control grips.

Enable “fix orientation” and set the joint spring and damping coefficients as needed to model your specific delineator response. It is also recommended to disable mesh contact before breaking to prevent unwanted interactions between the connected object.

In the below video, we show the final result using the above approach.

Passive objects

Rigid body delineator move with force tool

One possible variation on the above workflow, which allows for the possibility to have the delineators be passive objects (via contact > disable) is to use the force tool (learn more) to cause the delineator to pivot about the base rather than contact interactions.


Upcoming In-Class Training Opportunities


Non-rigid body delineator moved via graph time control

For a non-rigid body delineator, you can force it to rotate about its pivot using the time-control graph. First, adjust the delineator’s pivot by pressing [1] and [F2] on your keyboard, then switch to pivot selection type with [Shift+P]. Adjust the pivot position as needed. Since we want to force the delineator mesh to rotate about the base, lower the pivot to the base. After you’ve adjusted your pivot, press [Shift+O] to return to object selection type. In the example below, the pitch angle controller will be used; therefore, it is important to ensure the yaw angle is set appropriately such that when the pitch angle changes, the delineator rotates in the appropriate manner.

Next, go to the rotation local menu and left-click on the empty box to the left of the pitch input field. Next select the preferred time controller. Here we select “intervals” (learn more about the diagram tool).

Position and orient the group object as needed.


Tags: lane dividers, delineator, divider, flexible barrier.


© 2024 Virtual CRASH, LLC. All Rights Reserved