Introduction
Scan to BIM can be used for a wide range of Objectives. These may include:
Construction Monitoring
Developing As Built LOD 500 or greater level of Detail Models
Developing As Built Models of Heritage Buildings for Renovation.
Developing As-Built Models for Urban Renewal
As-Built Modeling of Facilities for Renovation and Re-Modeling
In addition, Scan to BIM process can be utilized for increasingly newer types of applications, that include many infrastructural facilities as well.
Scan to BIM Process
let us first understand the Process. Scan to BIM is essentially composed to three stages:
- On-Site Scanning
- Registering & Combining Raw Scans
- BIM Modeling
- On-Site Laser Scanning using Laser ScanningCameraLaser Scanning is done on site using special cameras. This could be done in Black & White or Color. Color Scans are clearer and are relatively easier to Model accurately.
- Registering Raw Laser ScansRaw Laser Scans need to be processed. There are typically multiple scans for a large facility. These multiple scans need to be combined using software such as Autodesk Recap Pro.
- Converting Registered Laser Scans to BIM. After processing Raw Laser Scans, they can be imported in BIM enabled software such as Autodesk Revit. Be sure, you understand the Scope of work and LOD required for deliverables.
On-Site Scans
- Define Scope of Work and level of Detail: It is critical that the scope of Wok is clearly and precisely defined for the Project.
- Define the Scanning Process and methodology: Define methodology and technology to be adopted before sending in field staff.
- Use High-Quality Scanners: Use High-Quality Scanners can produce point-cloud density needed for the specifications and LOD needed. High-Density Color Point Cloud Data is critical for high accuracy. Scan to BIM Model and can help you save. This is because of clarity in data, helps reduce Modeling time and as a result lower cost.
- Plan your scanning Process. Identify Camera Positions and ensure Circles of each Camera overlap.
- Support Point Cloud Data with Photographs and 360 Walkthroughs
.This helps modelers understand space and elements that are unclear in Point Cloud. - Field Notes can help in accuracy.Not all information is clear in Scan data, Field Notes take a higher priority over Point Cloud and result in a more accurate BIM Model.
Registration
- Number the scans sequentially.Number raw scans sequentially. This helps in aligning scans properly.
Modeling
- Verify Scope of work and LOD: Very often BIM Model produced does not match the required Scope or level of Detail that is required for your BIM Model. It is therefore important that every member of your team clearly understands this.
- Establish Survey Point: Identify and establish Survey Points if available in your scan Data and use them to establish these in your BIM Model.
- Pin your Point-Cloud: Once your Point Cloud is in Revit, ensure it is Pinned it so that it does not move by mistake.
- Setup Levels: When you import Point Cloud, you will need to establish levels. Your level 1 Plan may not show anything. Use 3D Elevation Views to establish levels.
- Adjust View Depths:
Without adjusting View Depths, you may see a huge amount of Points and these may become confusing. - Cross check:
Cross check your model against Photographs Field Notes and 360 Walkthrough to ensure accuracy and potential modeling inaccuracies.
