Laser scanning

Visual SLAM describes the simultaneous localization and mapping. This is the same process as with "normal" SLAM. A sensor is localized (tracked) and a map is built at the same time.

In Visual SLAM, cameras are primarily used. These are monocular, stereo and RGB cameras. In addition, there are other sensor systems which are used, e.g. visual inertial systems. Visual SLAM only works well in areas where there are sufficient visual differences.

Voxel is a unit on a regular grid in 3D space (a 3D pixel).

In meteorology, visibility is a measure of the distance at which an object or light source can be clearly recognised. To define visibility, a perfectly black object against a perfectly white background is viewed. At the distance equal to the visibility, the contrast ratio between black and white object is only 2%.

By definition a trajectory is the path that a moving object follows through space as a function of time. The term trajectory describes not just position over time, but position and orientation over time. The trajectory in mobile laser scanning systems and airborne laser scanning systems describe the position and orientation of the IMU over time. The trajectory is the output of the integrated IMU/GNSS system.

The system response indicates the shape of the echo signal within the receiver of the laser scanner system after ADC (analogue to digital converter) conversion, resulting from interaction with a flat target at normal incidence.

SOCS (Scanner’s Own Coordinate System) is the coordinate system in which the scanner delivers the raw data. The location and orientation of the SOCS with respect to the scanner’s housing is usually defined in the User Manual.

A retro-reflective target is a target with a high directivity of the reflected laser radiation. Examples of retro-reflective targets are reflective foils, corner cube reflectors, and retro-reflective paintings.

The pulse shape deviation is one of the additional attributes to each point of the point cloud. Low values indicate that the echo pulse shape does not deviate significantly from the system response. High values hint to echo signals with a significantly different pulse shape, which may arise from, e.g., merging echo pulses from several targets hit by the laser beam at only slightly different ranges.

GNSS (Global Navigation Satellite System) refers to a constellation of satellites providing signals from space transmitting positioning and timing data. GNSS provides global coverage. Examples of GNSS might be the USA's NAVSTAR Global Positioning System (GPS) and Russia's GLONASS

GLONASS, Global Navigation Satellite System, a radio based satellite navigation system operated for the Russian government by the Russian Space Forces.