Bring the Jobsite to Your Desktop with 3D Laser Scanning
With 3D laser scanning, whatever your eye sees can be measured to millimeter accuracy in only minutes. High-speed, non-contact 3D measurement devices collect – at lightning speed – high-resolution, panoramic images of the environment and objects near the scanner. Except these aren’t merely static images; these images hold spatial information that, in essence, digitizes the environment into CAD. This allows for precise measurements of even the smallest details, with accuracy to ¼ inch, and eliminates the need for survey crews to return to the site to pick up missed or more detailed data. The applications for 3D laser scanning are numerous, and include as-built documentation, industrial plant maintenance, volume calculations, ALTA, bridges and tunnels, retrofit and rehabilitation projects, new equipment installations, and manufacturing and process inspections.
McKim & Creed offers three different 3D scanning technologies: pulse (time of flight or TOF), phase-based (PB) and mobile scanning. TOF scanners utilize a “pulse” of laser light. This pulse is sent to the object and the time is measured from when it was emitted to the time it returns. The time and the encoder reference angles and then compute an x, y, z point, along with a reflectance value. TOF scanners are mainly used for long-range (100m +) measurement applications like topographic surveys.
PB scanners employ a “continuous wave” of laser light that is emitted at varying frequencies in a steady stream vs. a pulse. The different frequencies help the scanner cover different distances; a low frequency travels long distances and short frequencies serve well for close range, very similar to sound waves. The scanner receives the return waves and measures the “phase-shift” of the wave compared to when it returned. This shift calculates the distance from the scanner and, along with encoder references and inclinometer, calculates an x, y, and z value along with reflectance.
The main differences between PB and TOF systems are speed and range. Phase-based scanners are primarily used for indoor or piping scans (< 50m) where detailed scans are needed; scans are typically 3.5 minutes long.
Mobile scanning, provided by McKim & Creed’s MoDaC Mobile Data Collection® system, combines 3D laser scanning, GPS, inertial measurement and video technologies to collect dense and accurate 360-degree data from the safety of a well-equipped vehicle traveling at posted speeds.