Total station takes two-for-one approach

Two-for-one deals are always popular, but one doesn't often see them in the construction industry. However, that kind of value proposition is available in a new product designed for construction workflow verification – a robotic total station that offers dual functions to complete a layout and scan on a single setup.

"The key benefit that got me most excited by combining layout and laser scanning into one device is placing that device in the right person's hands," stated Taylor Cupp, technologist with M. A. Mortenson Company. "On our projects, that is the layout professional – now we can empower them to not only do layout, but also capture what is built for quality control. It's very beneficial because the person that knows how they've set up the job in terms of control points and those kinds of things can be the one to do that capture and get it as accurate as possible with one device."

Workflow components integrated

Topcon describes the GTL-1000 compact scanner as a first in the industry, in that all workflow components are integrated so it provides users with a live, "as built" model of projects, allowing the contractor to identify and rectify any discrepancies. 

"Our field engineering team has expressed interest in a product like the GTL-1000 for many years – a product that allows them to survey and scan within the same workflow and not have to spend time in the office registering scan data," stated Paulina Acosta, senior applied technology specialist with Rogers-O'Brien Construction, Dallas, Texas. "Each point cloud is geo-located before you leave the field. This makes them feel confident that the point clouds will be correctly positioned to our 3D models, without the need for visual alignment or the need to return to the field to acquire more data in order to make the registration work."

Nick Salmons, principal laser scanning surveyor at Balfour Beatty Construction, said "The new Topcon robotic scanning solution will increase productivity on site by accelerating the construction process and identifying design challenges more efficiently than traditional methods." 

Salmons also said it will benefit the industry as a whole by "reducing cost and program duration, for both clients and contractors alike."

Single button initiates scan

The system is designed so the user can initiate a scan with the press of a single button. A full-dome 360-degree scan can be created in a few minutes, according to Ray Kerwin, Topcon director of global product planning. "More traditional systems and methods take considerably longer," Kerwin said. "So, depending on the jobsite conditions, a contractor can get in and out quicker and thus minimizes safety concerns." 

A benefit Acosta likes: "We liked the ability to take individual as-built points with the GTL-1000 after it completes a full scan. This is helpful when you are trying to ensure that you captured the centre point of a sleeve or a structural connection. These points appear in the point cloud after they are processed and eliminate the time spent by our 3D modellers trying to determine the positioning of specific items in a point cloud."

The scanner is used in combination with ClearEdge3D Verity, a software tool designed to automate construction verification.

"The seamless integration of the unit and Verity creates a complete package that is perfect for construction verification using 3D modelling techniques," Kerwin stated. "The result is a system that offers full-dome scanning which can quickly capture duct work, columns, beams, girders, flaps, penetrations and structural steel. It helps to improve quality assurance, providing clear visual indication of construction-quality heat maps to minimize the effects of mistakes before they become expensive problems."

The system is designed to build upon proven prism tracking and accuracy that allows operators to establish points in most construction environments. 

The product includes on-board MAGNET Collage field software designed to process the data and offer real-time field-to-office connectivity. 

No added training needed

A key productivity benefit of the scanning robotic total station is that the site engineer requires no additional training and does not need to rely on outside scanning services. 

The new system is designed to take what was previously a rather lengthy specialty process and compresses all the steps, reducing the overall verification time.

The GTL-1000 was originally tested in the field by Balfour Beatty. 

"In our use and testing, we have found that the new robotic scanning solution will increase productivity on site by accelerating the construction process and identifying design challenges more efficiently than traditional methods," Salmons said. 

"We are delighted to have collaborated with Topcon over the last 12 months to trial this new tool, which will significantly benefit the industry as a whole; reducing cost and program duration, for both clients and contractors alike."

The benefits of the combined scanning robotic total station are also said to extend to subcontractors, who can share the verification data, meaning all parties are working from the same construction-quality heat maps. 

For example, the first electrical ducts and conduits can often cause problems, as alterations can often occur that go unnoticed. 

With Topcon's new system, the speed at which everybody working on the job can understand mistakes means the effects can hopefully be minimized before they become expensive problems.

As efficiency becomes increasingly important in the market, time cannot be wasted and mistakes cannot be tolerated. Clearly, the demand for quick construction verification is on the rise, which supports the need for new technologies that can help.

Jeff Winke is a business and construction writer.