Unable to access px4 with qgc in voxl 2 using usb-jst cable

modaltb

On VOXL2 J18 is a UART that connects to the DSP that is used for ESCs --> https://docs.modalai.com/voxl2-connectors/#j18-uart-esc

At this time, you need to use an IP connection to get to QGC.... Here's some options that I use on my bench:

https://docs.modalai.com/voxl2-hardware-setup/#wi-fi-connectivity
https://docs.modalai.com/voxl2-hardware-setup/#ethernet-connectivity

That cable above works with the STM32 based flight controller (Flight Core and VOXL Flight) but not on J18 of VOXL2.

Tamas Pal 0

@MODALTB could you please share a dedicated manual for running hitl with voxl 2 only ?
https://docs.modalai.com/voxl2-PX4-hitl/
The docs webpage is a bit confusing

Zachary Lowell

Hi Tamas, this video is how to get the voxl2 running with HITL: https://www.youtube.com/watch?v=ysvpJdXFWaM&ab_channel=AscendEngineering

Also - unless you are running the voxl-dev branch, then you will not be able to do a SERIAL connection from the voxl2 to QGC, you can only leverage a UDP connection. If you are running the voxl-dev branch and flashed the board, then you can leverage the voxl-px4-hitl executable and connect to QGC. However, you cannot have gazebo open simultaneously because the serial connection will then be interrupted.

If you wish to run HITL while running QGC, then run this using an FTDI cable and then turn on the required services (voxl-vision-px4, voxl-mavlink-server) and then connect to gazebo serially, and QGC via UDP signal.

Let me know if this makes sense.

Tamas Pal 0

I have flashed the voxl-dev branch files to the voxl 2's /etc/modalai/ folder. It seems like voxl-dev branch's voxl-px4-hitl is not an executable file. I am facing this issue.
voxl2:~$ voxl-px4-hitl
bash: voxl-px4-hitl: command not found
How to fix the problem?

Eric Katzfey

@Tamas-Pal-0 You can get a voxl-dev branch package from here: http://voxl-packages.modalai.com/dists/qrb5165/dev/binary-arm64/voxl-px4_1.4.19-202208111710_arm64.deb. Install that package instead of trying to copy files over manually.

Tamas Pal 0

@Eric-Katzfey
The voxl-px4-hitl is still missing in the package. I have installed it and tried to run voxl-px4-hitl command. It is not working. I have shared the terminal syntax below. How to fix it?

voxl2:/$ sudo dpkg -i voxl-px4_1.4.19-202208111710_arm64.deb
(Reading database ... 81777 files and directories currently installed.)
Preparing to unpack voxl-px4_1.4.19-202208111710_arm64.deb ...
Unpacking voxl-px4 (1.4.19-202208111710) over (1.4.19-202208111710) ...
Setting up voxl-px4 (1.4.19-202208111710) ...
Found DSP signature file
/
voxl2:/$ sudo apt-get install -f
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
voxl2:/$ voxl-px4-hitl
bash: /usr/bin/voxl-px4-hitl: Permission denied
voxl2:/$ sudo voxl-px4-hitl
sudo: voxl-px4-hitl: command not found

Zachary Lowell

Hi Tamas - please run a chmod +x /usr/bin/voxl-px4-hitl and that will enable permissions. After running that, you can run voxl-px4-hitl from any directory and it will work.

Tamas Pal 0

@Zachary-Lowell
Aftert running the voxl-px4-hitl command I am still gettting an output like this. Is it fine? If not how to solve the problem?

voxl2:/usr/bin$ chmod +x /usr/bin/voxl-px4-hitl
voxl2:/usr/bin$ voxl-px4-hitl 
Found DSP signature file
Setting GPS Parameters for HITL
INFO  [px4] mlockall() enabled. PX4's virtual address space is locked into RAM.
INFO  [px4] PX4 daemon already running for instance 0 (Success)
INFO  [px4] mlockall() enabled. PX4's virtual address space is locked into RAM.
INFO  [px4] PX4 daemon already running for instance 0 (Success)
voxl2:/usr/bin$

Eric Katzfey

@Tamas-Pal-0 Looks like px4 was already running. It was probably automatically started on system bootup using the systemd service. What is the output from voxl-inspect-services?

Tamas Pal 0

@Eric-Katzfey

voxl2:/$ voxl-inspect-services 
 Service Name         |  Enabled  |   Running   |  CPU Usage
---------------------------------------------------------------
 docker-autorun       | Disabled  | Not Running |  
 docker-daemon        | Disabled  | Not Running |  
 modallink-relink     |  Enabled  | Not Running |  
 voxl-camera-server   |  Enabled  | Not Running |  
 voxl-cpu-monitor     |  Enabled  |   Running   |     0.0
 voxl-dfs-server      |  Enabled  | Not Running |  
 voxl-imu-server      |  Enabled  |   Running   |     0.0
 voxl-mavlink-server  |  Enabled  |   Running   |     0.0
 voxl-modem           | Disabled  | Not Running |  
 voxl-portal          |  Enabled  |   Running   |     0.0
 voxl-px4-imu-server  |  Enabled  |   Running   |     0.0
 voxl-px4             |  Enabled  |   Running   |     0.0
 voxl-qvio-server     |  Enabled  | Not Running |  
 voxl-softap          | Disabled  | Not Running |  
 voxl-static-ip       |  Enabled  | Not Running |  
 voxl-streamer        |  Enabled  |   Running   |     0.0
 voxl-tag-detector    |  Enabled  | Not Running |  
 voxl-tflite-server   |  Enabled  |   Running   |     0.0
 voxl-time-sync       | Disabled  | Not Running |  
 voxl-vision-px4      |  Enabled  |   Running   |     0.0
 voxl-wait-for-fs     |  Enabled  |  Completed  |  
voxl2:/$

As mentioned by @Zachary-Lowell the voxl-px4-hitl file is not executable as shown in the youtube video https://www.youtube.com/watch?v=ysvpJdXFWaM&ab_channel=AscendEngineering
how to get the voxl-px4-hitl executable file?

Eric Katzfey

@Tamas-Pal-0 sudo chmod +x /usr/bin/voxl-px4-hitl

Tamas Pal 0

@Eric-Katzfey The voxl-px4-hitl is still missing. I followed all the steps but the executable file voxl-px4-hitl is still not there

voxl2:/$ wget  http://voxl-packages.modalai.com/dists/qrb5165/dev/binary-arm64/voxl-px4_1.4.19-202208111710_arm64.deb
--2022-08-25 10:05:37--  http://voxl-packages.modalai.com/dists/qrb5165/dev/binary-arm64/voxl-px4_1.4.19-202208111710_arm64.deb
Resolving voxl-packages.modalai.com (voxl-packages.modalai.com)... 35.215.116.197
Connecting to voxl-packages.modalai.com (voxl-packages.modalai.com)|35.215.116.197|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 5093080 (4.9M) [application/octet-stream]
Saving to: 'voxl-px4_1.4.19-202208111710_arm64.deb'

voxl-px4_1.4.19-202 100%[===================>]   4.86M  1.86MB/s    in 2.6s    

2022-08-25 10:05:41 (1.86 MB/s) - 'voxl-px4_1.4.19-202208111710_arm64.deb' saved [5093080/5093080]

voxl2:/$ dpkg -i voxl-px4_1.4.19-202208111710_arm64.deb 
(Reading database ... 81777 files and directories currently installed.)
Preparing to unpack voxl-px4_1.4.19-202208111710_arm64.deb ...
Unpacking voxl-px4 (1.4.19-202208111710) over (1.4.19-202208111710) ...
Setting up voxl-px4 (1.4.19-202208111710) ...
Found DSP signature file
/
voxl2:/$ apt-get install -f
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
voxl2:/$ sudo chmod +x /usr/bin/voxl-px4-hitl
voxl2:/$ voxl-px4-hitl 
Found DSP signature file
Setting GPS Parameters for HITL
INFO  [px4] mlockall() enabled. PX4's virtual address space is locked into RAM.
INFO  [px4] PX4 daemon already running for instance 0 (Success)
INFO  [px4] mlockall() enabled. PX4's virtual address space is locked into RAM.
INFO  [px4] PX4 daemon already running for instance 0 (Success)
voxl2:/$

how to fix this ?

Eric Katzfey

@Tamas-Pal-0 voxl-px4-hitl isn't missing. Your screen shot shows you executing it. But as I said in the earlier response you already have px4 running and when you execute the command it won't allow you to run a second instance of px4.

Eric Katzfey

@Tamas-Pal-0 In order to prevent px4 from running automatically in the background as a daemon on system startup use systemctl disable voxl-px4 and then sync. Reboot voxl 2 and then try voxl-px4-hitl again.