W W W . K A A R T A . C O M
8 3
Figure 58: Reflected surface (top) caused by scanning towards a mirror.
O C C L U S I O N S / M O V I N G O B J E C T S
There are situations with too many moving objects in a scene, or the field of view of Contour
is too limited, for the algorithms to determine x, y, and z coordinates.
Contour works best when it moves while the rest of the world stands still. Contour is fairly
robust and can tolerate up to 20 or 25% of the world moving before significant registration
errors occur to the overall scene. However, the moving objects still get registered as blurred
points or extruded tunnels, taking an otherwise nice 3D pointcloud and adding extraneous
points which must be manually excised. It is better to collect data without these artifacts,
when possible.
A common misconception is to think that the closer you are to an object, the more accurate
the measurement. Laser scanners use time of flight technology which is robust in terms of
distance errors. A good operating distance is 2-15m (6.5-50ft). Getting too close to objects
limits the amount of scan data Contour can use for optimizing the scan matching process.
SCANNER LOCATION
MIRRORS
REFLECTED SURFACE
WINDOW