# Waterlinked GPS Data log

**URL:** https://discuss.bluerobotics.com/t/waterlinked-gps-data-log/14777
**Category:** Software
**Created:** [July 25, 2023, 6:39pm UTC](https://discuss.bluerobotics.com/t/waterlinked-gps-data-log/14777 "2023-07-25T18:39:50Z")
**Posts on this page:** 1
**Showing post:** 8

<div class="post-metadata">

### Author: ![EliotBR](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/eliotbr/32/6937_2.png) [@EliotBR](https://discuss.bluerobotics.com/u/EliotBR)
#### Post date: [August 14, 2023, 8:58am UTC](https://discuss.bluerobotics.com/t/waterlinked-gps-data-log/14777/8 "2023-08-14T08:58:44Z")

</div>

> [@GavXYZ](#):
>
> I know the .ass files contain telemetry from different sensors.

The `.ass` files are generated based off whatever telemetry types are being shown in QGC’c telemetry widget during operation. From the available fields it doesn’t look like there’s one for visual odometry (which is what the DVL extension presents itself with to ArduSub), and the position ones look to be specifically for Gps messages rather than the vehicle’s position estimate, so I don’t believe it’s currently possible for QGC to put DVL things into its `.ass` subtitle files.

> [@GavXYZ](#):
>
> Alternatively, can it be done in post processing.

The vehicle has internal DataFlash `.bin` log files, and QGroundControl also logs the MAVLink messages it receives during operation in `.log` telemetry logs, which can both be parsed using [Log Viewer](https://ardupilot.org/dev/docs/common-uavlogviewer.html) or programs like Pymavlink’s [`mavlogdump.py`](https://www.ardusub.com/reference/data-logging.html#mavlogdumppy).

If you’re using `.bin` logs the [`VIS*`](https://docs.bluerobotics.com/ardusub-zola/software/autopilot/ArduSub-4.1/developers/log-messages/#viso) messages give you the information ArduSub is receiving from the DVL extension, and the [`POS`](https://docs.bluerobotics.com/ardusub-zola/software/autopilot/ArduSub-4.1/developers/log-messages/#pos) messages log the vehicle’s position estimate from ArduSub’s sensor fusion (its EKF). In `.log` files you can look at the [`GLOBAL_POSITION_INT`](https://mavlink.io/en/messages/common.html#GLOBAL_POSITION_INT) message data, and possibly also any `VISION_*` messages that get passed along.

---

_[View the full topic](https://discuss.bluerobotics.com/t/waterlinked-gps-data-log/14777)._