Survey Offset

On the Survey tab, in the Calculations group: Click Survey Offset to calculate point coordinates, using offset values along a straight line between two stations. The converted output from this function can be used as input to the Centreline to Solid function (on the Survey tab, in the Underground Tools group).

Conversion from Left, Right, Top, Bottom measurements to Width and Height measurements (with X and Y offsets) is supported.

Coordinates for each point (along the straight line) are calculated using the following:

D = Distance Station1 to Station2

dE =  difference in Easting between Station1 and Station2

dN =  difference in Northing between Station1 and Station2

dZ =  difference in Z between Station1 and Station2

d =  distance of point from Station1

East =  E(Station1) + d/D x dE

North = N(Station1) + d/D x dN

Z = Z(Station1) + d/D x dZ

Input/Output

Pickup file

Select a file type and then enter (or double-click to select) the name of the Pickup file. Calculated pickup points will be written to this file.

Stations

Station file

Double-click (or click on the Select icon) to navigate to the location of a Station file. This file will contain the names and coordinates of at least two known survey points. Typically, these will be points that lie in close proximity to the centreline of an underground working.

Station field

Double-click (or click on the List icon) to select the field that contains each Station identifier.

East, North and Z fields

Double-click (or click on the List icon) to select the fields that contain the Easting, Northing, and Z coordinates of each surveyed point.

Calculate Dimensions and Offsets

When this option is selected, converted width and (optionally) height measurements and their X and Y offsets will be written to the Pickup file.

Measured Values

Double-click (or click on the List icon) to select the fields to which Left, Right measurements will be written. If Height measurements are known, select the Height check box to enable selection of those fields to which Top and Bottom values will be written.

Calculated Values

Double-click (or click on the List icon) to select the fields to which the calculated Width and X offsets will be written. If the Height measurements check box has been selected, select the fields to which the calculated Height and Y offsets will be written.

Calculate Arch Wall Height

Select this option to calculate the curve and the height of an arch wall where:

Wall Height = Height – (Width * Rise-span ratio)

Rise-span ratio

Four commonly-used predefined ratios are available for selection. You can also choose to explicitly define the wall arch height.

Custom ratio

If you have selected the Custom ratio option, a numeric Rise-span ratio value can be entered here.

For example, to define the ratio 1/4 enter the value 0.25

Wall Height field

Double-click (or click on the List icon) to select the field to which the calculated Wall Height values will be written.