Find match vs. Tie Lines
There are two methods of strip adjustment in TerraMatch, Find Match and Tie Lines. The methods are compared in the following table.
Find Match |
Tie Lines |
|---|---|
Tool Find Match Tool Find Fluctuations |
Tool Find Tie Line Match |
Surface-to-surface matching |
Feature-to-feature matching |
Only one type of observation |
Several types of observations |
More time consuming adjustment |
Less time consuming adjustment |
New (better) observations for each iteration |
Old observations included for each iteration |
No manual observations |
Manual observations possible |
Input data |
|
•trajectories with time stamp •laser points linked to trajectories and classified into ground (and optional buildings) per strip •(optional) ground control points |
•trajectories with time stamp •tie lines derived from laser points, linked to trajectories by time stamp •(optional) ground control points |
Solvable parameters |
|
•easting, northing, elevations shifts •heading, roll, pitch shifts •mirror scale •easting, northing, elevations drifts •heading, roll, pitch drifts •fluctuating elevation |
•easting, northing, elevations shifts •heading, roll, pitch shifts •mirror scale •fluctuating easting/northing, elevation, heading, roll, pitch |
Observations |
|
•triangulated model from each strip surface •compares overlapping laser points and ground control points against this surface •translates observed difference and gradient to heading, roll, pitch, elevation difference |
•surface/section lines - follow direction of a surface •ground lines/points - located on paint markings •roof intersection lines - located at an intersection of two roof surfaces •known lines/points - located at known point locations |
