Output Selection

The Output tab the output configuration and status. You can choose to use the DVL dead reckoning position estimate (assuming a DVL is attached). You can choose to use the raw ROV Locator estimate (assuming an ROL Locator is attached. Or, you can choose a combined output, which does sensor fusion of the ROV Locator and DVL estimates, or if no DVL is attached, this option uses a filtered version of the ROV Locator estimate.

The figures below show a examples of the different outputs for a sortie in a challenging acoustic environment.

Sortie showing the filtered ROV Locator position estimate, DVL dead reckoning position estimate, and combined output position estimate. The operator was flying close to the surface, which can lead to ROV Locator noise due to multipath. Additionally, the operator was not careful getting the DVL’s GPS fix and the DVL started out with a substantial error. When we surfaced and took another GPS fix, the combined output was close to ground truth – approximately four meters, which is less than the expected GPS errors. This is the same input data as the previous figure.

CeruleanTracker Filter Note

Note that GPS systems require some time to acquire a fix and it takes more time to refine their estimate of location once a fix is acquired. The figure above shows the start of a sortie where the operator powered up and didn’t wait for the GPS systems to stabilize before taking off. The estimated position should eventually converge with the true position, although maybe not as quickly as happened in this sortie.