Coordinate System Tree

VG3 provides a unified coordinate system management interface, where all coordinate relationships between the physical world and the image world can be managed.

When performing camera calibration, simple camera calibration, long radius calibration (automatic), or long radius calibration (manual), it is necessary to establish entities that carry coordinate relationships in advance, that is, to establish coordinate system relationships in the coordinate system tree.

![](/media/202603/2026-03-13_151048_6396670.595377033961214.png)

1. A "Physical Camera" corresponds to a "Camera" in the "Coordinate System Tree".
2. A "Physical Robotic Arm" corresponds to a "Robot" in the "Coordinate System Tree".
3. The connecting lines in the "Coordinate System Tree" represent the coordinate transformation relationships between the connected coordinate systems, derived from calibration or mapping.
4. The direction of the connecting line between "Camera" and "Robot" represents the transformation direction between their coordinate systems.
5. Typically, a camera pointing to a manipulator is calibration, and transformation between two cameras is mapping.

For example, if we need to perform camera calibration to obtain the coordinate transformation relationship between the image coordinate system and the robot's coordinate system, we first need to establish a coordinate system entity for the camera and the robot in the coordinate system tree.

![](/media/202603/2026-03-13_151105_1277290.18217405031402545.png)

Coordinate System Group: Refers to a combination of multiple coordinate relationships.
Object relationships are presented graphically. There are two types of objects: Robot and Camera. Transformation relationships between objects can be added by connecting lines.

The generated calibration can be viewed by clicking the name on the right (double-click or right-click).

### Calibration Data

![](/media/202603/2026-03-13_150837_5523360.9029018886172837.png)

**[Calibration Data]** Displays the calibrated image and mechanical coordinates.
**[Data Analysis]** Analyzes the calibration data.

![](/media/202603/2026-03-13_150915_8719850.5206510007591293.png)

**[Transformation Method]** Forward Operation: Multiplies the transformation data by the calibration matrix, which can be used to test image point to physical point conversion; Inverse Operation: Multiplies the transformation data by the inverse of the calibration matrix, which can be used to test physical point to image point conversion.
**[Transformation Data]** Data used for testing.
**[Test]** Click the button to obtain the result after converting the transformation data.
**[Import]** Can import existing calibration files.
**[Export]** Can export the current calibration file.
**[Pop-up]** Can choose whether to enable pop-ups. If enabled, a pop-up displaying information about whether the calibration was successful and related calibration data will be shown after calibration.

### Mapping Data

![](/media/202603/2026-03-13_150956_0026830.8738244741144795.png)

Relevant mapping point posture and mapping information.

![](/media/202603/2026-03-13_151010_7028780.06869833069091458.png)
**[Transformation Method]** Forward Operation: Multiplies the transformation data by the mapping matrix, which can be used to test start point to end point conversion; Inverse Operation: Multiplies the transformation data by the inverse of the mapping matrix, which can be used to test end point to start point conversion.
**[Transformation Data]** Data used for testing.
**[Test]** Click the button to obtain the result after converting the transformation data.
**[Import]** Can import existing mapping files.
**[Export]** Can export the current mapping file.

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Click here to jump to the corresponding Chinese manual page: [Coordinate System Tree](/doc/326)