Setting GNSS Offsets (KB-AM019)

vGIS supports a wide variety of GNSS receivers, devices and antenna mounts. Each configuration places the GNSS antenna differently relative to the device’s camera, which introduces distortions in Augmented Reality. vSite AR features GNSS offsets to maintain the high accuracy of AR placement. It is important to define these offsets precisely to tell the system where the GNSS antenna is relative to the device.

To configure GNSS offsets, follow these steps:

1. Looking at the back of the device (so you can see the camera and not the screen), measure horizontal and vertical distances from the device’s camera to the antenna receiver
2. Launch vSite AR
3. Open Main Menu > Options > GNSS (Fig. 1)
4. Scroll to the bottom of the page
5. Use the sliders to set the values measured in Step 1 using the following logic:
1. If the antenna is to the right of the camera (Fig. 2a), use the positive X offset; otherwise, use negative;
2. If the antenna is in front of the camera (Fig. 2a and 2b), use the negative Y offset; or if it is closer to the user than the camera, use positive;
3. If the antenna is above the camera (Fig. 2a and 2b), use the positive Z offset; otherwise, use negative;

Note: Double-tapping on the slider will open a textbox to enter values using the keyboard

Configuration Examples

Fig. 2a:

• The antenna is to the right, in front and above the camera
• Therefore:
  • X is 14.0 cm (the antenna is 14.0 cm to the right of the camera)
  • Y is -7.0 cm (the antenna is 7.0 cm in front of the camera)
  • Z is 5.5 cm (the antenna is 5.5 cm above the camera)

Fig. 2b:

• The antenna is to the left, in front and above the camera
• Therefore:
  • X is -7.0 cm (the antenna is 7.0 cm to the left of the camera)
  • Y is -3.0 cm (the antenna is 3.0 cm in front of the camera)
  • Z is 5.5 cm (the antenna is 5.5 cm above the camera)

Fig. 1

Fig. 2

Have Questions? Feel free to Submit A Request to speak with a member of the vGIS Support Team.

Reviewed:  2024-09-17