02/16 Field Project: Using the New High Performance 3D Laser Scanner, the RIEGL VZ-400i

The new high precision RIEGL VZ-400i 3D Laser Scanner is one of the fastest 3D medium range laser scanners on the market! Its high repetition rate of 1.2 million emitted laser pulses per second and high scan speed of 240 lines per second, combined with a MEMS IMU for pose estimation enable a significant reduction of scanning time to less than one minute per scan position in the field.

In order to prove the high efficiency of the VZ-400i, a total of 514 scans covering approximately 4,5 km of city center roads with adjoining buildings, mostly in pedestrian zones, were carried out by just one operator within 8 hours of working time. The night time was selected because of the reduced number of people and traffic on the road. The scanner acquired full panoramic scans with 50 millidegrees scan resolution, leading to an average of 14 million range measurements per scan. The high pulse repetition rate, in combination with the high maximum measurement range (depending on the measurement program) of several hundred meters, required the scanner to be able to solve the occurring range ambiguities with RIEGL MTA (multiple time around) processing. During this recent test, the scanner was used on a carbon tripod with new rechargeable LiPo batteries.

The operator scanned one scan position after the other, with 9 meters in between scan positions, to capture highly detailed 3D information of that area. The high number of scans in the short time frame of 8 hours could be easily performed, due to the RIEGL VZ-400i’s capability to offer an easy single touch operation workflow on its touch screen. For the subsequent automatic registration algorithm, a chain-like order of scans and a number of planar surfaces to be found within the surrounding urban area were critical to the project's success. The rather short distance between the scan positions was chosen to eliminate most of the scan shadows on facades and roads and to ensure complete automatic registration of all laser scans.

After downloading the project within 20 minutes from the internal SSD hard disk to a laptop, all 514 scan positions were registered using RIEGL RiSOLVE into the Gauss Krueger coordinate system in about 8 hours. The entire stream-lined process is the fastest solution to acquire and register outdoor 3D scan data and enables rapid turnaround of critical information.

Project Conclusion

The RIEGL VZ-400i night scan project successfully digitally preserved various famous historical sights of Vienna such as the Stephansdom, the Peterskirche and the Hofburg, to name a few. The scanner's ease of use, rapid capture, and highly precise data show that archeology and cultural heritage documentation are just a few of the applications that the RIEGL VZ-400i is an ideal tool for. It took only 8 hours to collect over 500 high-resolution scans but provides the possibility to visit such sites in digital form for future generations. With the new VZ-400i high performance 3D laser scanner, RIEGL offers an extremely fast field-to-office terrestrial laser scanning solution, thereby redefining productivity!

Vienna Unesco World Heritage Site

Within the last 20 years, RIEGL has demonstrated a long-standing commitment to the preservation of cultural heritage sites, using different laser scanners and scanning systems for archeology and cultural heritage documentation, RIEGL has digitally preserved many major historical sites such as the Egyptian Pyramids, the Sphinx of Giza, the Domitilla Catacombs in Rome, Frauenkirche in Dresden and numerous other significant monuments.

Vienna’s downtown is one of the most famous cultural sites in Central Europe and its historical architecture displays a very complex urban area structure. The historic center of Vienna has been listed on the UNESCO World Heritage List since 2001.