To position the machine

Use machine positioning to position a machine, typically a drilling rig, relative to the tunnel.

To position the machine relative to the tunnel, the software calculates positions on the horizontal alignment at the nominal station and at the station defined by the drill depth. A reference line is calculated using these two positions.

The reference line cannot be calculated if the:

  • nominal station is before the start of the tunnel
  • drill depth is zero
  • drill depth results in a station beyond the end of the tunnel

Once the reference line is calculated, the transverse and vertical offsets from a measured point to a position calculated perpendicular onto the reference line are displayed, along with the longitudinal offset from the calculated position on the reference line to the calculated position at the tunnel face.

You can use these deltas to position the machine.

1

Instrument position

2

Nominal station at tunnel face

3

Calculated position on the alignment projected from 2

4

Drill depth

5

Calculated position on alignment at drill depth

6

Reference line

7

Measured point

8

Calculated position on reference line projected from 7

7 to 8

Transverse and Vertical offsets

9

Longitudinal offset

  1. Start a survey.
  2. Tap and select Machine position / Machine positioning.
  3. Select the tunnel file. Tap Accept.
  4. Enter the Nominal station of the tunnel face. Key in a value or tap Measure and measure the station.
  5. Enter the Drill depth.

  6. Tap Next.

    The calculated station and elevation values and coordinates for the two positions defining the reference line are displayed along with the azimuth and grade of the reference line.

  7. Use these values to confirm the reference line. Tap Next.

    The offsets from the measured point to the position calculated perpendicular onto the reference line are displayed, along with the longitudinal offset from the calculated position on the reference line to the calculated position at the tunnel face.

  8. Use these deltas to position the machine.
  9. If required, enter Construction offsets. You can enter a:
    • Transverse offset – to offset the reference line left or right of its computed position
    • Vertical offset – to offset the reference line up or down from its computed position
  10. Tap Finish.