Aerial triangulation

     Aerial Triangulation

     Aerial Triangulation represents the mathematical process of establishing precise and accurate relationships between the individual image coordinate systems and a defined datum and projection (ground).

     The main objective of aerial triangulation is to produce from ground control, sufficient points in the photogrammetric models to ensure that each model can be oriented accurately as required for stereo compilation in either orthophoto or line mapping.

     Image to ground

     There are mainly three stages of aerial triangulation:

     • Point identification of ground control
     • Numbering settings for points, images and strips
     • Input data: flight details (photo coordinates plus omega, phi and kappa rotation), camera calibration and scanned or digital images

Image Measurement
     • Interior orientation (fiducial marks measurement for analogue cameras)
     • Automatic tie points determination using images pyramid levels
     • Ground control points measurement
     • Manual tie points measurement if necessary (in cases where automatic measurement could not determine an acceptable number of tie points per image or in failure situations)

Block Adjustment
     • Input of observations (x, y, z coordinates or GPS/IMU, ground control) and initial parameter values
     • Preliminary data processing, including generation of initial values for bundle adjustment parameters
     • Iterative solution (including specials algorithms for determination of blunders and error propagation)
     • Acceptance of results (after accuracy and reliability assessment)
     • Final output of results (EO data)

     Our aerial triangulation processing services covers all types of cameras, from older analogue sensors (RMK , RC30 etc) to newest digital sensors, small or large format (DMC, Vexcel UltraCam, IGI Digicam etc).