4. Derive Error Surface

MBES GCD Help‎ > ‎Tutorials‎ > ‎Workflow Tutorials‎ > ‎

ET-AL Recommendations to IPC

ETAL developed two FIS error models for IPC's use with MBES. One relies on just roughness and slope as an input, whereas the other also includes the MBES-derived TU (total uncertainty) point estimate. ETAL recommends that IPC use the simpler two input FIS we developed, as the TPU is overly conservative.

Using the FIS (see here for how to load FIS to GCD FIS Library), and associated surfaces loaded in previous step, you can run the FIS to derive an error surface. The video demonstrates this:

FIS Uncertainty Surface

This video shows how you can calculate an FIS error raster using a pre-loaded FIS and associated surfaces as inputs:

GCD 6 - Creating a Spatially Variable Uncertainty Model with a FIS

For more information on fuzzy inference systems and how they can be used to calculate elevation uncertainty surfaces, see here. For conceptual background on fuzzy inference systems in general click here.