Graphically select the points and / or vectors to consider in the simulation.
Points and / or vectors can be selected graphically. If you have a CAD model vectors can provide additional information
Fabricating Measurements
Pressing the Fabricate button causes SA to evaluate which of the selected points / vectors should be included in the analysis for a particular camera and builds measurements to them if they fit the criteria. Points must be within the established field of view and not obscured by any surface in the job file. Vectors must also fit the criteria of points and have an incidence angle less than the established limit. Shots will be fabricated and shot lines will become visible for points or vectors that fit the criteria. These parameters can then be viewed individually or as a group using the camera network controls.
Running the Bundle and uncertainty analysis
Once measurements have been fabricated, the camera network and point locations are passed to V-Stars for analysis and to perform the full bundle. The V-Stars application must be running for this to hap- pen.
When complete, the uncertainty covariances are then returned to SA and saved within each point’s properties. This provides the uncertain- ties reported in the point properties and includes the full CoVariance matrix returned from V-Stars which can be accessed as part of the observation properties saved within the point.
For clarity these covariance values are maintained with the point and should directly match those reported by v-stars. This bypasses the Monte Carlo simulation process performed by other instruments in SA and no uncertainty point cloud is produced.
The errors can be visualized using the ellipsoid display enabled on the Analysis tab of the User Options.
There are a couple of parameters to verify is the simulation does not run correctly. These currently include the following:
The camera focal length cannot be entered as ZERO. Doing so will cause the simulation to generate an error from the V-Stars application when it is run.
Verify that the points included in the simulation process have unique names.
Saving and Loading Camera files.
Camera files can be exported to an ascii or csv file and re-imported. What actually gets stored are i,j,k vectors and upon retrieval, these get converted to appropriate angles which are not always what you started with, but are equivalent.
If a camera file does not load, double check that the format has both a “Carriage Return” and a “Line Feed” by opening the file in notepad++.