Issues with Navigator Flight Controller usage

Can the Navigator Flight Controller use the connector above to transmit the data read by the external sensor to the pi 4 without using BlueOS?

Hi @KaiBo -
Welcome to the forums!
Your picture didn’t come through, what connector are you trying to use? The Navigator breaks out the Pi 4 hardware serial ports, so you can absolutely access them or the I2C data without using BlueOS…

I mean using the ports on the flight controller to connect the sensor, then transmitting the data to Python (in VSCode) for processing.
And how can I know what port is it? like USB name is ttyUSB0
Thank you

Hi KaiBo -
Maybe this guide is helpful for what you’re trying to do?

I think it need BlueOS as well.
I have installed the sensor directly on the navigator, but the pi4 still can’t read Is it the library that I didn’t download bluerobotics_navigator in python?
I’ve plugged and unplugged the navigator, and he doesn’t show up on the pi4.
Has anyone ever done this?

thank you

Hi @KaiBo -
Please provide more information - what sensor are you trying to use? How exactly is it connected? How is your code attempting to access it, and how are you running it? If you’re using the BlueOS Terminal, have you taken the red-pill?


Sorry, my image didn’t upload up.

The first problem at the moment is that there is no way to read the port, such as the VScode picture, and the bar30 example program is compiled.

The second question is, I am connected in the same way as in the picture, and then there will be DVL, sonar, Scanning, and my pi 4 wants to receive the data from the flight controller board and send it to VScode, not through BlueOS, is this possible?

If there is any information that needs to be provided, please tell me, thank you.

My goal is to make an AUV, and the role of the flight controller is to provide a port for me to connect the sensor and send the gyroscope data to the pi 4
I’m not a native English speaker, so I’m sorry if there’s something wrong with my text.

thank you

Hi @KaiBo, Have you checked these instructions? Instructions Navigator Lib

I presume that you are trying to interface the sensors on Raspberry Pi without using the BlueOS image, is that right?

If this is the case, in order to access i2c/spi/uart on Raspbian, you need to set the overlays (this is done automatically in BlueOS).

If they are set, you will be able to check i2c devices available: please follow this to check.

Hi @KaiBo -
Please try to use I2C detect as described in this guide. I would guess you are connecting your script to the wrong I2C bus.

The DVL and most sonars we offer communicate via ethernet, with the exception of the Ping single-beam sonar. You can connect it to a USB to serial adapter, or one of the Navigator serial ports.

Can I ask why you are avoiding BlueOS? It would make much of your development much easier! There is a vscode extension in BlueOS as well…

Hi there,
I tried using BlueOS and convinced the professor, but currently there are three problems

The first problem is that Qground doesn’t work, I can’t connect to the line, my IP and firewall have been changed, and the hardware connection method is Ethernet to USB plugged into my computer.

The second question is whether the BlueOS operation is on the computer or external screen, my external screen will always show me to log in, I have the manual, and the BlueOS web page will be displayed on the computer screen, is that correct?

The third question is where BlueOS writes the code and where the sensor is displayed when plugged in

thank you

thank you

I found a place to download VScode, as shown in the picture, is this right?

The question is whether I have written a program that allows me to control my AUV. Or is there a specific place for me to write before it works?

Hi @KaiBo -
Writing software to have the unit function as an AUV is a major undertaking!

To get QGC to connect, you need to make sure that your control computer is set to the default IP that the Mavlink Endpoint is directed to - 192.168.2.1, although you could add another address. This is not required if you’re using Cockpit!

I think you’re asking where BlueOS is running for your second question - it is hosted by the Raspberry Pi, so you can pull it up anytime you’re connected. I’m not sure what you are referring to by

I have the manual

What sensor are you trying to plug in? Is it already supported by ArduSub? If it’s the bar30 you shared earlier, and you’re running Ardusub, it’s data is available via Mavlink2Rest, you can check it under Available Services.

It looks like you installed the VSCode extension correctly. You can use it to develop code, yes. I find the extension is a bit heavy, and prefer the jupyter notebook or direct execution from the Terminal

As you can tell from my links, the docs are your friend!

Hi @tony-white

I’ve changed the MAVLink IP, but QGC still shows “Disconnected.”

2.My Raspberry Pi 4 is connected to the computer via Ethernet, and an HDMI cable is connected to a monitor. On the monitor, the Pi 4 continuously displays the BlueOS login screen asking for a password. Is this behavior correct?

3.All sensors I’m using are produced by Blue Robotics, except for an additional gyroscope I purchased separately (I haven’t integrated it yet).
Should I download ArduSub directly within BlueOS, or should I use its software to view my sensor data?
Alternatively, do I need to download additional software like QGC? If so, which version should I download? I’ve checked the GitHub documentation but still feel unclear about what to do.

Or, should I use the MAVLink2REST tool in the interface shown in the image to view the data through the watcher? If that’s the case, how can I access the sensor data?

Thank you for answering me

Hi KaiBo -
Can you ping 192.168.2.2 from your connected control computer? If not, you have a connectivity issue preventing access to the Pi 4.

Theh login screen is indeed what you would expect to see if you connect a monitor.

ArduSub does not support external gyroscopes by default, so getting that sensor to work may require modifying the firmware, which can be a difficult process for some.
That said, a bar30 pressure sensor and Celsius temperature sensor should be plug and play for ArduSubfirwmare- this is easy to install from the Autopilot Firmwarepage in BlueOS. Youc an see what versions of software we reccomend in our technical reference, QGC 4.2.8 should work for receiving telemetry - you can see the pressure and temperature data by adding them to the parameters displayed in the bottom center black instrument panel. This is covered in the integration guides for both sensors.

What other sensors are you trying to interface with?

If you’d like to develop custom code to receive and log values, you can see the available messages by clicking the /mavlink2rest link in the webpage column within the Available Services page you shared a screenshot of.

Hi @tony-white

  1. I am operating everything through a computer, but QGC still cannot connect.

2.I can already see the data from the pressure sensor, but I want to use this data for control. Do you have any recommended methods?


I prefer to use python

  1. What is the account password displayed on the connection screen? Is there a default ledger?
    Probably not that

Hi @KaiBo -
It looks like you can reach BlueOS ok. If QGC doesn’t connect please verify you have a Mavlink UDP Client endpoint configured to point at your computers IP address - there is the default route to 192.168.2.1, but I would guess that you haven’t set your IP address to that?
Python can easily get the data from the rest interface (including scaled pressure)- see how that is achieved in this example, which is the code used in this guide. This code is run in a docker container within BlueOS, you can replace the “host.docker.internal” portion of the mavlink2rest web address with the IP of the vehicle if running/testing externally.

The screen you show is where the vehicle name and DNS hostname are configured - best to leave that alone. If you’re trying to log in via SSH, the default username password is Raspberry / Pi, respectively.