SLAM stands for simultaneous localization and mapping. It was developed in the 1980s for robotics and has been used to guide self-driving cars and common household robotics such as the popular iRobot Roomba vacuum cleaner. Technically speaking, SLAM is a relative positioning concept based on sensor inputs such as photos or laser scans. It computationally creates a map of an unknown place while simultaneously tracking the location. The algorithms used depend on the sensor type, so different algorithms are used with photos than with laser scan data. So what does that have to do with building construction?
In basic terms, SLAM is like having GPS indoors – you can be oriented or your position can be known without GPS satellites, survey control points, total stations or WiFi. Although the technology primarily relies on software, it also requires the right hardware to collect enough of the right types of digital data for the software to analyze and stitch together. The more redundant the data, the more accurate it is. This can be achieved by collecting data from the same position and by collecting other positioning data from devices such as inertial measurement units (IMUs). With indoor mapping, there are lots of opportunities to “close the loop” to create more accurate data. For example, when you enter a room, you have to cross the very same place the exit the room. This simple process helps to achieve accuracy. This process of “closing a loop” or double passes” also helps to mitigate “drift” or inaccuracies in data over time.
So now let’s imagine that SLAM technology would make it possible to bring true registration-less mobile scanning and photo documentation to building construction with unprecedented accuracy. How would that affect the construction process?
Let’s take it a step further. What if SLAM technology:
- Could be integrated into a scanning process to eliminate point cloud registration (stitching together of point clouds)?
- Could be integrated into drones so they could fly inside buildings and collect data?
- Could be integrated with total station so reorienting (resecting) was no longer needed?
- Could be used on construction equipment to monitor locations inside and outside the building?
When these capabilities exist, they will revolutionize building construction by dramatically improving the way field data is collected and processed. How close are we to seeing these changes take place? This is just one of the many topics we will address at HxGN LIVE 2015 in Las Vegas. Join us to learn more, and share your comments below.