Terrain Calibration

Two ways to get anchor positions: measure with a laser meter and type the distances (below), or let the anchors measure themselves against a cross of reference tags — see Anchor auto-calibration, which needs no laser and no typing.

Laser Measurements

Equipment: a laser distance meter.

From a reference point marked on the floor (the stage 0,0 origin), measure:

Measurement	Description	Example
A0 height	Floor to anchor A0	2480 mm
0,0 to A0	Laser from origin to A0	4200 mm
A1 height	Floor to anchor A1	2500 mm
0,0 to A1	Laser from origin to A1	3800 mm
A0 to A1	Laser from A0 to A1	6100 mm
A2 height	Floor to anchor A2	2510 mm
0,0 to A2	Laser from origin to A2	5100 mm
A0 to A2	Laser from A0 to A2	4300 mm
A1 to A2	Laser from A1 to A2	5900 mm

Caution

laser distances are 3D (direct line). Topos automatically projects to 2D by subtracting the vertical component.

Enter in Topos

1. In the right panel, section calibration anchors
2. Click DEVERROUILLER (unlock)
3. Enter for each anchor:
   • Height (mm)
   • Distance to origin 0,0 (mm)
   • Inter-anchor distances (mm)
4. Click CALIBRER (calibrate)
5. Topos computes x,y,z positions and applies them immediately
6. Computed positions display below the fields

Antenna Delay Calibration (precision)

To improve accuracy from ~50 cm to ~10 cm:

1. Place a tag at a known distance from an anchor (e.g. 2.00 m)
2. In the config device panel, connect the anchor via USB
3. Send in the terminal: AT+GETANT? — read the current value (default: 16336)
4. Observe the measured distance in the dashboard
5. Adjust: AT+SETANT=<value> then AT+SAVE then AT+RESTART
6. Repeat until convergence
7. Only calibrate anchors (not tags)