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What does a typical Laser Scanning process look like?

Laser scanning is a widely used technology in various industries, including construction, architecture, engineering, and surveying. It involves the use of a laser scanner to create a three-dimensional (3D) model of a site, which can be used for a range of applications, including design, analysis, and visualization. In this article, we will explore what a typical laser scanning process looks like.

laser scanning process

Let’s explore the steps involved in implementing laser scanning technology, which include:

Scanning

Laser scanning is not only about creating impressive visuals but also about collecting accurate information. In theprocess, it is crucial to identify the purpose and desired outcome of the physical act of surveying, as this technology allows us to seamlessly recreate any environment. Generally, scanning a site can be broken down into two steps: pre-site work and work on-site.

Pre-Site Work

Pre-site work involves understanding the extent of the work. It includes the information to be gathered during the survey, the essential areas to be covered, specifics of the site or facility such as square footage, levels, elevations, ceiling types, existing building conditions, project timeline, among others.
It’s essential to finish the extent of data capture since that will form the basis of your proposed survey strategy and define the primary focus of the scan. Additionally, depending on the type of work and facility to be scanned, making sure you comply with the necessary paperwork is another important step. For example, COI requirements, specific clearances, work permit, safety certificates, on-site contact information, unrestricted access to the survey site, and so on. During the pandemic and post-pandemic times, scanning may require an additional layer of safety and training to safeguard your staff.
Based on the existing information provided in the form of blueprints or photos, define a tentative workflow to be followed on-site to prevent loss of time and mitigate potential obstacles. Pre-site work, when combined with a detailed survey work path, can yield top-notch point cloud results, which form the foundation for all future models. Also, have a Plan B in case of unforeseen complications arising on-site.

On-Site Work

Before you start scanning, it is advisable to review the available information, walk around the site and coordinate with others to remove any objects, such as tiles, access panels, furniture, or scaffolding, that could potentially obstruct accurate data collection.
Once the defined project parameters have been established, the surveyor can begin scanning on-site while adjusting the density of data points collected to meet specific requirements. It is recommended to adhere to the pre-planned work path to anticipate upcoming scan positions, but be prepared to adapt the strategy according to the site’s conditions.
Moreover, it is crucial to pay close attention to the vital information that needs to be gathered on-site. Field notes should also be incorporated abundantly to assist the user in understanding how the fieldwork was carried out.

Registration Process

The registration process is carried out in the office after the completion of fieldwork. Once the scanning process is finished, a significant amount of data is stored in a compressed format on the scanning device’s hard drive. This data is then downloaded and processed to become the point cloud through a process known as registration. Software programs such as Cyclone, Scene, and ReCap are commonly used for registration. In these programs, millions of overlaid data points are “threaded or stitched together” to create a continuous project point cloud.
During registration, false data points are removed. The information collected is then converted to a standard transfer format, spread homogeneously to describe conditions inside and out. It is advisable to provide the scan positions to the user to help them identify data points in both the point cloud and 3D model format, allowing them to detect and resolve any potential conflicts.
Some service providers offer pre-registration alongside scanning to accelerate the registration process. However, the quality of the scan heavily relies on the precautions taken in the field, as well as meticulous notetaking.

Data Cleanup Process

After stitching all the scan positions together and completing the registration process, the next step is to start the data cleanup process. During scanning, extra information such as digital artifacts, vehicles, trees, people, and measurement noise is filtered out. This helps to improve the accuracy and clarity of the final point cloud data. The aim is to ensure a high-quality point cloud suitable for modeling.
Although data cleaning offers apparent advantages, it is often overlooked due to being a time-intensive process. However, it is recommended to take the time to complete this step to ensure a consistently high-quality scanned product.

Export

Exporting deliverables is a crucial step in the process. Fortunately, there are several universal formats that are supported by many design applications, making it easier to share your work with others. However, in some cases, it may be necessary to convert your files from one format to another to be able to use them with specific software.

At Sirvey, we work with a variety of clients who use different design software. Many of them rely on Autodesk Suite – specifically AutoCAD and Revit – which require files from ReCap. In these cases, we recommend requesting the RCP and RCS formats, or e57 if you’re using Bentley products, to get the POD file you need.

By using these recommended formats, you can make sure your design files will be compatible with the software your clients or collaborators are using, which can save you time and hassle in the long run. So, regardless of the project’s size or scale of collaboration, it’s important to choose the right format for your deliverables.
If you’re interested in requesting a point cloud survey through Sirvey, it’s important to understand our design workflow. While getting as-built models can be highly beneficial, we prefer having data available in RCP and RCS formats for building models, and to refer to the point cloud or insert it in Revit, AutoCAD, or Navisworks. This can help you avoid going back to the surveyor or the S2B models.

Additional point cloud formats

We offer additional point cloud formats, including unified and decimated point clouds, 360 photos, and structured point clouds. These formats may be necessary for pre-processing with automated geometry extraction software such as Edgewise.
It’s also important to consider the size of the point cloud. If you have a large project with multiple zones, areas, or levels, we recommend splitting the point cloud for ease of handling. At Sirvey, we strive to keep the point cloud file under 10 gigabytes.
By understanding our design workflow and considering these important factors, we can work together to provide you with the best possible results for your point cloud survey needs.

laser scanning process

File Transfer: Streamlining Your Workflow

The final step in the laser scanning process is file transfer. This step should be factored into your work plan as it can be time-consuming. It is important to keep in mind the standard principles of intellectual property and data ownership that apply to project deliverables. Typically, the surveyor retains ownership of the information and provides the client with a royalty-free license for defined purposes.
At Sirvey, we use ACC – Autodesk Construction Cloud for uploading, sharing, and storing point clouds as it offers unlimited space.
In addition, licenses may be needed to visualize and work with point clouds and 360 photos. There are plenty of options available. Some of them are free but come with limitations, while others require a paid license. Laser scanning service providers often offer 360 photo viewers through applications like WebShare by Faro, JetStream (TrueView) by Leica, and 360 ReCap by Autodesk.
To view and work with the 3D point cloud, the following applications licenses are required:

  • ReCap – where you can view and fly through the 3D point cloud
  • Open Software/Online Free Viewer (with limitations)
  • CloudCompare
  • Revit/AutoCAD/Navisworks – not a point cloud visualizer, but it’s possible to review the point cloud.

Conclusions

Over the past decade, Building Information Modeling (BIM) and laser scanning have made significant progress. Due to their many practical applications, they have become the preferred solution for producing quick, efficient, and precise surveying data for many construction professionals.
If you’re searching for fast and reliable data to generate accurate building models for your next project, look no further. Contact Sirvey today to benefit from our trusted and advanced 3D laser scanning service, which will enable you to deliver your best project yet!


Do you want to learn more about Laser Scanning? Read more here!

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How to Ensure Reliable Laser Scanning Outcomes for BIM Coordination?

Laser scanning can be a powerful tool for supporting BIM coordination. However, to obtain reliable laser scanning outcomes, certain considerations need to be taken into account.

laser scanning outcomes

Laser scanning technology has revolutionized the construction industry, providing a highly accurate method of capturing existing conditions and creating as-built models for building information modeling (BIM) coordination. Although laser scanning has been in use for some time, each project presents unique learning opportunities for reality capture processes. To ensure reliable laser scanning outcomes for supporting BIM coordination, consider these five suggestions.

1. Perform Scanning After Demolition

For reliable scanning deliverables, it is advisable to perform the scanning after the demolition phase. This way, only the remaining elements are translated into existing condition models, eliminating confusion between project parties. In case this was not possible, you can utilize Revit phases to achieve the same purpose.

2. Ensure Sufficient Coverage

LIDAR scanners work by emitting laser beams that bounce back from objects in their path. However, LIDAR can only capture what is in its line of sight, which means that objects that are obstructing the view can obscure smaller elements. For example, large ducts or structural beams can hide smaller objects that are located behind them. This is a critical limitation to keep in mind when conducting LIDAR scans. To ensure that no elements are left out in the scan, the technician must take as many shots as necessary to guarantee sufficient coverage. This means that the technician needs to move around the target area and take scans from different angles to ensure that all the elements are captured.

3. Using 360° pictures to identify pipe systems and types

Mostly used for modelling, 360° pictures also can be grateful to identify pipe systems and types. Depending on the desired outcome, they can be taken in color or gray scale. When used for identification purposes, color capture is often the preferred option. However, capturing color in above-ceiling spaces can be challenging due to insufficient lighting. In these cases, grayscale may be a better choice.

4. Implement Survey Control

Survey control may be necessary to enhance accuracy and ensure proper alignment of the point cloud and to establish a shared coordinate system, depending on the scope of the project. It is advisable to engage BIM Managers and coordinators at an early stage in this process. All stakeholders downstream should adhere to the project standards, which must be documented in the project’s BIM Execution Plan (BEP).

5. Create Proper As-Built Models to clash against

Clash detection against point cloud data cannot be performed using Navisworks. Thus, it is advisable to include the primary existing structural components and systems in the coordination model. Generating accurate as-built models can significantly minimize the number of Requests for Information (RFIs) during the coordination process.

laser scanning outcomes

Laser scanning outcomes: Final thoughts

The considerations listed above are general guidelines to follow when planning to incorporate laser scanning technology into your projects. However, each project has unique characteristics that may pose specific challenges. Proper planning is crucial in the laser scanning process, and our technicians spare no effort in ensuring that they have everything they need to carry out a successful survey.
If you need assistance in planning your next scanning project, please contact us, or send your request through www.sirvey.us, and we will coordinate the entire process for you.

Read more about laser scanning benefits for the AEC industry here!