2017 Issue

60 S ome things are just meant to be together, baseball and hot dogs, the Fourth of July and fireworks and of course, 3D laser scanning and BIM. To better understand the rela- tionship between 3D laser scanning and BIM, let’s talk about what both of them are. What is 3D Laser Scanning? 3D laser scanning technology is just that, laser scanning. This technology accurately captures all available visual information of a site or building. There are several different scanners out there capable of capturing 50,000 to over a million survey grade points per second. Yes, you read that correct … 50,000 to over a million survey grade points per second. I heard your whispered “WOW” right through the pages. The scanner collects points through a 180° degree rotation. The scanner works by combining a laser emitted beam, a mirror deflecting the beam towards the scanned surface, and an optical receiver, which detects the laser pulse reflected back from the ob- ject. Since the speed of light is known, the travel time of the laser pulse can be converted to a precise distance measurement. Typically this data is collected from each set up in less than 5 minutes. The group of points from each setup is referred to as a “point 3D Laser Scanning and BIM, Going Together Like Baseball and Hot Dogs… By Henry Fox, McNeil Engineering cloud.” The point cloud from each set up is then registered or “stitched” to- gether so that one measureable point cloud is created for the entire scanned area. The point cloud can then be modeled in AutoCAD, Revit, or other 3D modeling software packages to capture all available visual information for analysis. What is BIM? Building Information Modeling (BIM) is a digital representation of physical and functional characteristics of a facility. A BIM model is a shared digital model for providing information about a facil- ity, used to show existing conditions or new design. Building Information Modeling (BIM) is changing how buildings, infra- structure, and utilities are planned, designed, built, and managed. BIM solutions help turn information into perspective and deliver business value at every step in the process. BIM is a model-based process that provides insight to help you plan, design, construct, and manage buildings and infrastructure. BIM has been key in helping builders and their clients discover the value of virtual construction. Study after study has shown that constructing a build- ing virtually first, with all of its various systems in place, (plumbing, HVAC, electrical, structural, architectural, etc.) can save 10%, 20%, 30%, of a build- ing’s construction cost or even more, by eliminating costly change orders due to unforeseen conflicts in the field. For example, imagine the benefit of knowing your 80” x 30” supply duct is going to run into the main steel support beam for the building BEFORE it sits hanging from the underside of the floor above, termi- nated three feet from this huge steel beam, while architects, engineers and builders try to figure out the cheap- est way to reroute this beast. Picture them drawing straws to decide who gets to explain to the owner why the project is delayed and why it has gone over budget. Benefits of 3D Laser Scanning For BIM Now that we have a basic understand- ing of what 3D laser scanning and BIM are, we can now take a look at the relationship between the two. BIM isn’t just for new construction. BIM is an important tool if you are doing a major remodel or are just making mi- nor changes. Let’s look at some ways that 3D laser scanning can help in this process. Laser scanning allows you to create as-built models with unparal- leled accuracy. No more having to use manual means to capture data.