3 Questions to ask before Deploying Reality Capture to the Field

Reality capture is the use of various technical means such as 360 cameras, LiDAR, and UAV’s, to capture a digital 3D model representation of your construction site. The point cloud and photogrammetry generated from the hardware, otherwise known as “digital twins”, can be used in various applications and help throughout the phase of your project. 

While there are many reasons to create these “digital twins” and have everything integrated into your BIM (Building Information Model), there are some practicalities and questions that should be addressed before you deploy in the field. 

What type of space do you need to capture, and how big is it?

One of the first things to consider before deploying reality capture to the job site is what needs to be captured. Every job is different and depending on the site location and condition, you can narrow down the list of the necessary hardware and time required to successfully complete the job.

Exterior capture requires hardware that is not sensitive to sunlight and is easily mobilized. 360 cameras often meet this requirement as they are compact and are able to capture in a wide variety of lighting conditions. If the space requires laser scanning, oftentimes a terrestrial laser scanner is the most appropriate tool for the job. A terrestrial scanner will generate the most dense point cloud and is capable of tighter registration in environments lacking reference geometry that a mobile SLAM based scanner would rely on. Our team has seen successful results from the Leica RTC and Faro laser scanners while particularly large outdoor scopes of work may be best suited to the Leica P-series scanners. If you require large outdoor space to be captured, drones may also be an extremely useful tool and can even be utilized to capture spaces that may not be safe for humans to work within.

There are a variety of options for reality capture of interior spaces. The majority of 360 cameras in the market will capture high-quality images to clearly display existing conditions on-site. Depending on the building type and the end-use of the point cloud, there are a multitude of scanners to select from when scanning indoors. Reality capture deployed in commercial office spaces tends to be quicker than residential captures as you may require fewer scans to capture the same square footage. Manufacturing and warehouse buildings do not have partition walls so fewer scans are typically required, however, they do require longer high-intensity scans as they tend to have high ceilings and much more complex MEP and structural systems elevated high above the slab of the building.

What do you plan to do with the data?

While the environment within which you plan to capture will have a dramatic impact on the type of hardware you will be required to deploy, the end-use of the scan must be equally considered as their specific needs will likely determine the correct tool for the job.

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For simple documentation and visually monitoring the progress on the job, the majority of 360 cameras are sufficient. Floors 30-40K square feet are captured in less than an hour and can be shared with anyone almost instantly. Project stakeholders will have access to see the progress or issues on the job without ever needing to visit the site. 

For deviation analysis reports a terrestrial scanner should be used to achieve the best results. The majority of terrestrial scanners from Leica, Faro, Trimble, and more will be able to capture data that is optimized for deviation analysis. If survey-grade accuracy point clouds are to be captured, the Leica P-Series is a great option. It is however worth keeping in mind that it would take more than double the scanning time in comparison to the other scanners like the RTC360. For typical construction applications, our team has found the more agile Leica RTC, BLK, and Faro series scanning to be a fair compromise of agility and accuracy.

Mobile scanners, although they are less accurate than their counterparts, tend to capture data in less time and oftentimes are considered accurate enough for the task at hand. Mobile scanners work very well for progress monitoring when deployed with platforms like Avvir Progress and they can also be used for lower LOD Scan-to-BIM services. We have seen a big play on mobile scanners recently with all of the big scanning hardware manufacturers launching their own mobile scanners. With the competitive nature of this mobile scanning technology environment, we are seeing great leaps forward in both the accuracy and clarity of scan data coming from new mobile devices, furthering their potential for deployment on construction jobsites.

How frequently will you need to capture this data?

Cost is always a driving factor when planning for reality capture deployment. The interval at which your jobsite is required to be captured will have a significant impact on cost and must be considered during the planning stage. If reality capture is only needed at the beginning of construction to accurately display the existing conditions of the site then it is worth spending the time and money on an accurate scanner like the Leica P-Series that we mentioned earlier. 

If scanning is required once every couple of months, a scanner like the Leica RTC360 will be perfect for the job. Although it is not as accurate as of the Leica P-Series, it will still capture high-quality dense point clouds while keeping an accuracy satisfactory to the majority of tasks 

If your project requirements have you planning to scan more than twice a month, you would be advised to consider mobile scanners, as they could drastically cut down on field and processing time and associated costs. As reality capture technology continues to advance, we have seen Mobile LiDAR technology play a big role in construction. Mobile scanners can capture up to 250,000 square feet per day. The accuracy of mobile scanning has always been a drawback to many customers; however, the mobile scanning hardware manufacturer NavVis is changing that. Their VLX scanner can hold real-world accuracies of 8-12 mm and the accuracy only increases when utilizing survey control on site. Mobile scanners are a great option for frequent scanning and job documentation, especially if survey-grade capture is not required.

Scanning a job site every couple of weeks or months throughout the phase of the project is very important; however, 360 cameras may allow you to capture your entire project with a fraction of the time and effort typically required to scan. 360 cameras are a great tool for tracking both progress and quality control on the jobsite and are often a valuable tool for the project management, ownership, and design team as well. A 20,000 square foot floor can be captured in 10-15 minutes and all the parties involved can track exactly what is built on the job and if the need arises anyone can go back at a specific capture date and see what the progress was at that particular point in time. 360 cameras are a great tool for frequent documentation to track and monitor progress made on the job site.

Conclusions

There are a multitude of questions you can ask prior to deploying reality capture to the field, but the three questions above can drastically help narrow down the necessary hardware that is required to efficiently get the job done. Having an understanding of the space you will be capturing, the end use of the captured data and the frequency at which the data must be captured will all play a major role in determining the best hardware to deploy to the field.