How to Conduct Reference Line Stationing

Reference Line Stationing's Purpose

Reference Line stationing is very similar in purpose to Free Stationing. It lets you start measuring and recording existing conditions without using imported control points.

How Reference Line Stationing is different, however, is that the station establishes its coordinate location based on a line you measure during the stationing process. This means that the coordinate locations of the objects you measure will be in relation to the line you use during stationing. Therefore, if referencing your measurements back to a specific line and keeping a coordinate system that is relative to that line, Reference Line Stationing could be perfect for you.

Note that the default application it will start you with after stationing is line layout, but you can proceed with any other applications when you are ready - more on this below.

You need a blank project before proceeding with Reference Line Stationing (no existing coordinate information, such as points or a CAD file). The software will prompt and help you make sure this is the case.

As mentioned above, Reference Line Stationing's core use case is to perform as-builts for existing field conditions and, particularly, guide you based on a specific line you establish. These as-builts can then be used for several reasons:

1. Prepare a digital design to fit the as-built conditions
2. Troubleshoot the as-built conditions to compare them to your digital control point set up
3. Perform quality control of pre-laid out objects

It is likely that you will find your own unique use cases for using this station set up as well, given its convenience.

When should you not use Reference Line Stationing?

If you have been given existing control points within a specific coordinate system to work with, using Reference Line Stationing is likely not the stationing option you need. It would likely be better to first attempt to station via control points before resorting to use Reference Line Stationing.

Remember that control points have specific coordinates given them within a design. When you station on the coordinates as the design calls for, it allows for total station measurements to also be directly aligned to the digital design.

Reference Line Stationing is for when you are working in a situation where you can create your own coordinate system based on a specific line of your choice, that you can use independent of a specific digital plan.

How-to Step 1: Create a Blank Project

Simply open the project application and create a new project - just make sure not to import any points or CAD files into it. Make sure that is the active project you are working in.

How-to Step 2: Click on "Reference Line Stationing"

Once you have your active "blank" project, you can click on "Reference Line Stationing" from the home screen.

How-to Step 3: Identify your Line

Identify a line in the field that you would like to be your reference line for this stationing.

The software will take the first point you measure on this line and treat it as the "0,0" coordinate for the project you are creating. The second point you measure will be the "northern" direction of your coordinate system, and will represent the (0,N) location of your CAD plan.

For example - let's say I measure my first point (which automatically is saved as the (0,0) coordinate location of my plan). Then, I measure a point 10m away. Automatically, that second point would be saved as the (0,10) location on my plan in the tablet.

If I proceed with these coordinates, the location of my points will all be in relation to this coordinate system. For instance, if I measure a point that is 1m to the right of the line, and 2m "north" of the (0,0), or, starting point, I will have recorded a point that is at the (1,2) coordinate location.

You will understand how the coordinate system works as you practice with reference line stationing on your own. For this step, however, simply find the line you want to measure and determine which point along the line you would like to represent your "start" point, or, your "(0,0)" point.

How-to Step 4: Measure Locations on your Line

As mentioned above, proceed with measuring the line you select. The software will guide you to measure your first and your second points, as in the screenshots below. As always, make sure your target type is correct (prism/laser), depending on how you are measuring.

Your first point will be automatically saved as "BL 1" (Building Line 1), and the second will be saved as "BL 2" (Building Line 2). You will also have the option of measuring a 3rd point ,"BL3" (Building Line 3) if you need to re-set where the "0" northern value begins on your plan. Measuring a BL3 is rarely required for most use-cases, but it remains an option if needed. The screenshots below will show you what this stationing process looks like.

Prompt asking you to measure first point:

Prompt asking you to measure second point:

Prompt showing you your current set up, asking you to set up a station height (not necessary if you turn heights off):

Prompt asking you to measure a 3rd point to "reset" the starting northern location of your line (not necessary if you would prefer BL1 to be the project's "0" northern location - this can be skipped):

Visual of where the 3rd point was measured, for reference - this point will be saved in your point list:

Note, if the above stationing is accepted, the "northern" location of BL3 will be you're projects "0" northern point instead of BL1. BL1, however, will remain your projects "0" east/west point location:

How-To Step 5: Set Station Height (if Needed)

If you are working with heights, you will need to set a station height. See this article for more help on how to set a station height. However, simply pressing the "set station height" button on the right side under the "Summary" tab should guide you through the process.

If you are not working with heights, simply go to the settings gear at the top and turn heights off (or on, if needed). With heights off, the station height step will also not appear.

Note, if you set a station height during this process, it is always possible to go back and adjust it later if you made a mistake. You can do this during the stationing process, or by going to the edit station height button from the home screen after you have completed your station. See screen shots below:

How-To Step 6: Perform a Line Shift (if Needed)

While not common, you can perform a line shift if you see it pertinent to your set up. This step will adjust where the line layout application will guide you after you finish your stationing. Remember - the application immediately following this stationing method is line layout. This article discussing "line layout" also talks about line shift, for reference.

See the screenshots below for various shifts in the line.

In each example, I am asking the software to shift the original line I measured to a new location - my official coordinate locations of BL1 and BL2 will stay the same, but the line that the line layout application will guide me to after I finish stationing will change based on how I shift the line. The "new" line that I shift to is represented by the BL1' and BL2' point labels.

Example 1: The line is shifted 2m north, 1m east, and turned 90°.

Example 2: The line is shifted 5m north, 1m east, and is turned 45° from its original orientation.

Example 3: The line is shifted 5m south, 10m west, and 120° from its original orientation.

Again, it is rare that you will use line shift, but if you would prefer the software to guide you based off of a line different from the one you measured, using "line shift" is a good option for you. Practicing with this will help you learn how to use this best in your situation. If forgot to shift your line after stationing and wish you had, you can always go back into the line layout application and re-create the line you want to layout.

How-To Step 7: Begin your Measuring Applications

Your station is now established and has a coordinate location based on the line you measured. You can now begin to do various applications, especially measuring and recording as-built conditions on your jobsite.

Note that if you exit the line layout application, the tool will warn you that you are moving from a "control line" set up to a "Coord / Graph" set up - meaning that if you intend to re-station on this project in the future, you will need actual control points.

If you are only doing Reference Line Stationing to do line layout applications on a project you do not intend to use again, then this doesn't apply to you. However, if you intend to come back to this set up at a later time, or do anything other than line layout, you will need to establish control points to station on this project again in the future.

Using the measure and record application is a great way to establish control points to use in the future.