# To automatically scan positions

Use auto scan to measure points at a defined scan interval for selected stations. The measured positions are compared to the design template surface for that station.

If parts of the tunnel profile do not require measuring or cannot be measured (for example, areas behind ventilation ducts), add a scan zone to measure only points within the scan zone(s). Scan zones are applied to the entire length of the defined station range.

## To auto scan positions in the tunnel

1. Start a survey.
2. Tap and select Survey / Auto scan.
3. Select the tunnel file. Tap Accept.
4. Define the scan station range:

   1. To define the Start station and End station, you can:

      - Key in the station value.
      - Tap and select List and then select one of the design station values from the TXL file.

      - If you can see the station range that you want to scan from your position in the tunnel, tap in the Start station field and then turn the instrument to the required start point of the scan and tap Measure to calculate the station value. Repeat the process for the End station.

        If you are using a Trimble instrument that has VISION technology, you can tap in the map toolbar to view the video feed and then tap the location in the video (for example the prism or tunnel wall), and then tap Measure to calculate the station value.

      To scan in the direction of decreasing station, enter a Start station value that is greater than the End station value.

   2. Enter the Station interval used to determine subsequent station values. Tap and make sure that the correct interval method is selected:

      - The 0 based method is the default method and gives station values that are multiples of the station interval. For example, if the start station is 2.50 and the station interval is 1.00, the 0 based method produces stations at 2.50, 3.00, 4.00, 5.00, and so on.
      - The Relative method gives station values relative to the start station. For example, if the start station is 2.50 and the station interval is 1.00, the Relative method produces stations at 2.50, 3.50, 4.50, 5.50, and so on.
   3. Select the template surface to scan.

   4. Tap Next.

      The selected station range is shown in the plan view. If you need to change the station range, tap Back and edit the Start station and End station values.

5. Tap Next.

   The cross section of the first selected station is shown. The selected template surface is highlighted.

6. If only part of the tunnel needs to be measured:, add a scan zone:

   1. Tap and hold on the screen and then select Add scan zone.

   2. Point the instrument to where you want the scan zone to start. The instrument ray appears as a solid red line on screen. Tap Accept.

      Scan zones must be defined in a clockwise direction.

   3. Point the instrument to where you want the scan zone to end. The instrument ray appears as a solid red line on screen and the scan zone start appears as a red dashed line. Tap Accept.

      The auto scan profile view appears. Points outside the scan zone are grayed out and will not be measured.

      To add another scan zone, repeat the steps above.

7. Tap Start.
8. Configure the Scan settings. Tap Accept.

9. Configure the Scan tolerances. Tap Accept.

   The Tunnels software begins scanning the first station.

   For each scanned point, the point name overbreak / underbreak and delta station values are displayed. Each scanned position appears as a green circle (if within tolerance) or a red circle (if not within tolerance).

   Once all points for the current station are scanned, the Tunnels software automatically advances to the next station until all selected stations are scanned.

   Once all points for all selected stations are scanned, results show which stations have errors. Expand each record to view more information.

10. Tap Close.
11. To exit the plan view, tap Esc.

To end the scan before it is complete, tap Stop, or tap Pause to pause the scan and then tap Continue to resume scanning. While paused, you can select any scanned position to view the deltas. If you are using a Trimble VX spatial station and the VX scanning check box is enabled in the Settings screen, tap Stop and then tap Start to resume the scan.

- Auto scan defaults to tracking mode for each scan but will work in standard mode.
- When a scan starts, the DR target height and prism constant are automatically set to 0.00.
- When scanning with On station adjustment selected and using a:
  - Trimble S Series total station or Trimble SX10 scanning total station, each point is scanned until it is found within tolerance.
  - Trimble VX spatial station, fifty points will be scanned at a time. The scan is repeated for those points that were not within tolerance.
- If the number of iterations is exceeded or the EDM times out, the point is skipped.