Automatic Mapping in QGC via MAVLink with DVL A50 Sensor

General Discussion
1

Hello,

In my project, I want to use the DVL (Doppler Velocity Log) sensor to estimate the position of my vehicle under water and display these estimates on QGroundControl (QGC). My goal is to both track the position of the vehicle instantaneously using DVL data and automatically create a route on the map.

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(The red line represents the path previously taken.)

Do I need to convert DVL data to MAVLink format?
If so, how?
Or what are your suggestions? How can I do it?

Thanks

2

Hi @omer_1 -
This is quite possible, have you seen the instructions here?

3

Hello @tony-white,

I could not reach neither “http://waterlinked-dvl.local/” adress nor “192.168.2.95”

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I am using ethernet switch and dvl a50 is connected to it. My DVL’s green light is blinking (I guess there’s no problem) I power it with 12 volts.
How could i reach dvl’s page?
I tried to connect without ethernet switch (connection directly to my pc via ethernet cable)

4

Hi @omer_1
Sorry for the issue! Does 192.168.2.95 respond to pings from the terminal?
Is there a reason you’re powering from 12V, instead of the battery voltage of the system?
I assume you’ve configured your own computer IP correctly, since you can reach the BlueOS interface…

If you continue to have issues, please reach out via our support form with the order # so we can better assist you.

5

Hello @tony-white ,
I can control my ROV using BlueOS i did configurations correctly.
I tried connecting the DVL directly to my computer (right) and also tried connecting from the raspberry via my rov (left).

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As you can see, i can connect DVL on my computer but i could not connect from my raspberry.

Is it possible to see when i run ifconfig command on my raspberry to see DVL ethernet connection as “192.168.2.95” ? Because when i check it, i could not find.

Also i checked DVL on BlueOS

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When i try to view logs, i take these errors.

6

Hi @omer_1 -
Please try enabling the DHCP server on BlueOS, and see if that gives you the ability to ping the DVL from the BlueOS interface as you previously attempted.

To run ifconfig, you must first take the red-pill at the terminal. After this, ifconfig will show that the BlueOS ip address is 192.168.2.2 - this is the same subnet as the .2.95, which should allow the device to reach the DVL.

Have you made any network configuration changes on the system prior to this? Those errors align with the issue, as you can’t reach the IP address from BlueOS as required.

1 Like
7

Hi @tony-white,

Thanks for helping me. I found that I could not connect to the dvl due to the wrong connection of the Ethernet switch. Now, i have another question for you :slight_smile: .
In python script i can read datas like,
“time”: 106.3935775756836,
“vx”: -3.713480691658333e-05,
“vy”: 5.703703573090024e-05,
“vz”: 2.4990416932269e-05,
“fom”: 0.00016016385052353144, etc…

I need to convert to real world datas (i mean coordinates). How could i obtain that? QGC can help me?

Thanks

8

Hi @omer_1 -
Glad you found the issue! Indeed, the jst-gh ethernet ports for 1 and 5 are used by the full-size RJ-45 connectors, so you must use one of the middle 3 for the DVL.

The data you’re pulling from the DVL are the velocities it is sensing - this is what a DVL measures! This velocity is integrated by the autopilot to produce a position estimate. You might find this position estimate in the appropriate message on the Mavlink2Rest interface - take a look through the data available under this service heading on Available Services (must be in pirate mode to see.)

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