In general, data provided by MLS systems can be characterized with the following technical parameters:
- Point density in the range of 100-1000 pulses per m2 at 10 m distance.
- Distance measurement accuracy 2-5 cm.
- Operational scanning range from 1 to 100 m.
To be able to verity and compare the accuracy of MLS systems, a permanent test field for mobile mapping systems was established in Espoonlahti, about 16 km west of Helsinki. The test site covers 1700 meters of road environment. Altogether 58 terrestrial laser scannings were collected to obtain reference targets for geometric accuracy analysis. Test field is used also for algorithm development and testing.
Reference data was collected using vehicle-based terrestrial laser scanning.
Several commercial and research MLS systems have mapped the test site and the results show that in good GNSS conditions an accuracy of a few centimeters both in plane and elevation can be reached. The results of the accuracy analysis have been published in Sensors and were also presented at the XXII Congress of the ISPRS in Melbourne.