Fully Automatic using ABGPS/IMU

We consider the expert performance of the FAAT to be absolutely essential to the overall success of a project in that it is a strong diagnostic tool for analyzing ground control and photogrammetric accuracy.

With ABGPS, a GPS reading of the camera’s spatial location is taken at the instant of each photograph. A reading is also taken from the aircraft’s IMU (Inertial Measurement Unit) which measures the tip, tilt, and crab of the plane at the moment of the photo. These datasets are photogrammetrically analyzed and processed to produce an accurate XYZ coordinate on the ground at the center point of each photo. The benefit is that ABGPS significantly reduces ground control requirements thus saving money. IMC expertly exploits the value of this technology and has utilized ABGPS on hundreds of projects.

Using our state-of-the-art Trimble Inpho Match-AT software, IMC precisely performs automatic digital aerial triangulation based on the AGPS/IMU data collected during the photography mission. Automatic and manual tie point matching is done on the entire set of imagery to best contribute to the strength and quality of the block. Match-AT is very powerful and accurate in pixel matching and in setting up large or small blocks of FAAT. IMC uses this technology very successfully and have triangulated over 80 thousand frames so far ranging from dozens of counties to small projects as other mapping firms all over the country have relied on our expertise in this facet of photogrammetry

Conventional Aerial Triangulation

Using the basic horizontal and vertical control survey data, IMC establishes 6 horizontal and vertical points per model by means of analytical aerial triangulation. The FAAT adjustments are performed using Albany software, and the data is measured on our Softcopy Stations or on Analytical Stereo Plotters.

The accuracy of the analytical triangulation will be less than 1 part in 10,000th of the flight altitude and is determined by the root mean square (RMSE) of the AT ground control residuals. Accuracy of the analytical aerial triangulation can also be verified by the inclusion of checkpoints with the values withheld in the adjustment and later verified in the final results.

A sealed and signed copy of the aerial triangulation is delivered with each project.