> For the complete documentation index, see [llms.txt](https://stage-precision.gitbook.io/grid/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://stage-precision.gitbook.io/grid/spatial-interactive-experiences/building-an-interactive-tracking-project/create-the-point-cloud-volume.md).

# Create the Point Cloud Volume

Once the sensors are connected and aligned in the shared project coordinate system, they can be combined inside a **Point Cloud Volume**.

The Point Cloud Volume is the central processing object for the spatial tracking pipeline. It collects the point data from its child sensors and provides the processing stages used later for defining the tracking area, filtering, clustering, Zones, and data output.

***

## Add a Point Cloud Volume

To add a Point Cloud Volume:

1. Right-click an empty area of the **Project Tree**, or click the **+** button.
2. Use the search field to find **Point Cloud Volume**.
3. Select it to add it to the project.

<div align="left"><figure><img src="/files/yLAaiUiukgXZTm3jSVtG" alt="" width="255"><figcaption></figcaption></figure></div>

***

## Add Sensors to the Point Cloud Volume

Sensor Objects are assigned to a Point Cloud Volume through the Project Tree hierarchy.

For a single sensor:

1. Locate the **Sensor Object** in the Project Tree.
2. Drag it onto the **Point Cloud Volume**.
3. Drop it below the Point Cloud Volume so that it becomes a child.

<div align="left"><figure><img src="/files/XnLeMlkJ2DDtpbjgqrWs" alt="" width="257"><figcaption></figcaption></figure></div>

For multiple sensors, you can assign them at the same time.

* Hold <kbd>SHIFT</kbd> to select a continuous range of Sensor Objects.
* Hold <kbd>CTRL</kbd> to select individual Sensor Objects.

Once all required sensors are selected, drag the complete selection onto the **Point Cloud Volume** and drop them below it to make them children.

<div align="left"><figure><img src="/files/vK9Gx5Hh6RSRK19pkW3B" alt="" width="256"><figcaption></figcaption></figure></div>

The Point Cloud Volume now receives and combines the point data from all of its child sensors.

Because the sensors have already been aligned in the same project coordinate system, you may not see an obvious visual change in the Viewport at this stage. The points were already being drawn at their correct spatial positions before they were assigned to the Point Cloud Volume.

What changes is the processing structure: the Point Cloud Volume can now treat the sensor data as one shared point cloud for the following stages of the project.

Individual Sensor Objects can still be shown or hidden independently in the Viewport. This can be useful later when inspecting sensor coverage or troubleshooting individual data sources.