Tag: 12d Model

Manual entry of traverse data into the Least Squares Dialogue can be time-consuming and, when calculations are involved, can introduce the risk of human error. To address this challenge, Queensland Rail (QR) developed a utility to streamline the process by automatically extracting observations from a field file and generating the required Horizontal and Vertical Least Squares input files.

The utility also helps keep field files clean and manageable by reformatting attribute data, assigning the correct data identifiers, and removing unpopulated attributes. By automating these tasks, the workflow reduces manual effort and screen clutter while improving efficiency and consistency throughout the survey processing process.

The team at Queensland Rail (QR) had the idea to develop a tool that would create input files to be read by the horizontal and vertical least squares dialogues in 12d Model software. The program would read a field file and extract all the observations to the control points and write the data out to the *.in and *.lin text files. This would save a lot of time compared to manual entry, and remove human error. The files could be read into the Least Squares dialogues and processed.

The manual input of traverse data into the Least Squares Dialogue in 12d Model can be prone to user error when manual calculations are involved. As a response, QR set out to develop a utility that creates a Horizontal Least Squares Input and Vertical Least Squares Input files from the field file. The Horizontal Least Squares Input file was to have the extension YourFileName.in. The Vertical Least Squares Input file was to have the extension YourFileName.lin. The files were to be saved to the same location as YourFileName.fld.

The attribute reformat was written at the same time that the 12d Attribute Macro was developed. At that time, the Macro only removed the white space 73 lines, not the unpopulated attribute. Hence the functionality was included in this tool.

To enable the proper use of the attributes attached to a given observation code, the attribute had to be given its correct attribute type. The line identifier in the field file is used to determine the data type and therefore the way 12d Model can handle the attribute. With the QR Code library set up for generic use, the reality is that the majority of feature codes will not have a populated attribute attached to an observation code in every instance.

The created tool reads the field file and interrogates each code attribute and reassigns the correct data identifier to the attribute and deletes any unpopulated attributes.

This utility reformats the field file attribute data and removes all unpopulated attributes with the goal of only displaying useful information instead of empty descriptors in the project.

The tool developed reads a field file and extracts all the observations to the control points and writes the data out to the *.in and *.lin text files. The files are read into the least squares dialogs and processed. The control model created is then used in the field file reduction to control the processed observations. Screen clutter is reduced, and efficiency increased—saving time and money.

Download this Case Study as a PDF HERE.

For more than 55 years, Tomlinson and Carruthers Surveyors Ltd has delivered surveying and engineering services throughout the Wairarapa region of New Zealand. As the firm expanded beyond its traditional cadastral surveying roots into more complex engineering and subdivision projects, it sought efficient workflows that could keep pace with evolving industry demands. On a recent Local District Council subdivision and road vesting project in Masterton, Surveyor Derek Roberts and the team leveraged 12d Model to manage every stage of the project—from cadastral data creation and design through to GPS survey preparation, drafting, and final plan production. By combining 12d Model with GPS technology, the team significantly reduced field and office time, streamlined workflows, and improved accuracy, demonstrating how modern surveying practices can deliver substantial productivity gains on real-world projects.

Surveyor Derek Roberts said, “I think the engineering design work we’re now doing is increasing due to a buoyant and expanding industry, combined with new staff and a new curriculum in the New Zealand Surveying degree that has covered changing technology such as using 12d Model and GPS.”

“For example, 12d Model was used extensively on a recent project in the northern end of Masterton, near a big roundabout on the way out of town. The land concerned is known as ‘the horseshoe’, which was part of a significant local car park.”

“The project started as a straightforward two-lot subdivision to provide a council-owned car park with the balance remaining in private ownership. On closer inspection it was found that a larger than normal percentage of the land was actually being utilised as road. To formalise the situation these areas were vested as road in the ownership of the Local District Council. The back of the footpath was used to define the inside lot boundary with the outside being the existing Certificate of Title boundary (road carriageway). In conjunction with this, to the south-west there is part of a river with an open stream flowing through the area. The stream actually forms a natural boundary which we picked up to be compared with the underlying data in preparation for a future project.”

“We did absolutely everything in 12d Model for this job, including creating all cadastral data, design, CAD and plotting. We started by creating our scheme plan (plan of proposal) in 12d which was plotted out and used as part of the application, and then survey pre-calcs were completed within 12d before visiting the site. This information was uploaded into the GPS unit directly from 12d, so when on site we were able to walk directly onto these marks via coordinates rather than having to use conventional methods. This in particular has meant a huge saving in time and also given us a different approach to the majority of our jobs.”

“The information gathered by GPS and also conventional instruments was then downloaded into 12d Model. This data was used to form the basis of the 12d traverse spread sheets through which the majority of the linework for the title and survey plans was prepared and submitted on A2 litho paper. As this project was done using GPS, we also had to use the transformation functions to work out and apply the appropriate scale factors. Using GPS combined with 12d Model’s interface for processing pre- and postdata has probably halved the time required on site. A project of this nature would take approximately two weeks’ worth of work spread over the different stages, including about three days in the field and five days’ worth of calculations and drafting. This is phenomenal compared with the time it would have taken using conventional methods!”

“For Tomlinson and Carruthers, the major benefits of using 12d on this and similar projects have come from the 12d traverse spread sheet – in particular the way it does all the line work, point symbols and annotation of the plan all at once. This has the advantage over other software because 12d is able to calculate and annotate the true information rather than just the projected information.”

“Once the information is in the 12d traverse spread sheet, the drafting is done automatically. This means the potential for human error – which occurs mainly with reading and writing at the different stages – is kept to a minimum while the whole process is simplified and sped up. We are finding that using 12d Model in conjunction with GPS is saving us around 30-50% of our time spent on this and other projects. 12d’s ability to reduce errors has served us well, particularly with the use of GPS and electronic data recorders. Though you can never beat independent checks, the Traverse Spread Sheet Drafting has removed one of the more difficult areas to police.”

“Luckily, we have found that the training curve for 12d is very small, even for those with minimal CAD experience. For new users of 12d, probably half the learning time has been spent gaining an understanding of survey calculation methods rather than of 12d itself. Ease of learning was particularly facilitated by the ability to set up default files and screens to standardise procedures throughout the office and the whole firm.”

“Being a former SDR Map user, I found the 12d traverse spread sheet very appealing and easy to use overall. 12d has really revolutionised our methods and our approach to the majority of our projects!”

Download this Case Study as a PDF HERE