PX4 Community Q&A: February 15, 2023

February 15, 2023

Join us


  • Community Announcement
  • Community Q&A
  • General Discussions

:loudspeaker: Community Announcement

A.1 :

:people_holding_hands: Community Q&A (No deep technical discussions)

:exclamation: Guideline for asking a Question

  1. Specify what you are trying to achieve
  2. Specify what environment / platform you are using
  3. Prepare a Link or Document to help understand if possible
  4. First, ask the question on Discord or create a Github Issue!
  5. If you take over 5 minutes for the question, please continue in Discord or a Github Issue.

Q.1 : STATUS_TEXT MAVLink Message Frequency - Farhang

Can we change it to 1Hz, instead of 20Hz (default)? Using 4G Network.

  • Used for a lot of legacy things (e.g. Calibration)
  • MAVLink Warnings, etc. are included in STATUS_TEXT

Answer: Depends on network frequency. If worried can add ID (sequence) number to make sure we don’t loose any messages over the network.

Reference: Events Interface | PX4 User Guide

Q.2 : Robot Competition Rover Controller - not7CD

Do I need to write attitude & position controller? Attitude control is working already in Simulation.

Action Item: Create an Issue in PX4-Autopilot Github Repository on the vehicle dynamics desired, or a Pull Request.

:heavy_check_mark: Done here: Omnidirectional surface vehicle controllers for position and attitude by not7cd · Pull Request #21138 · PX4/PX4-Autopilot · GitHub

Q.3 : RTK setup - @mwbb

How to setup RTK, with different RTK modules (does QGC support them all?). Have private NTRIP server, and would like to connect from QGC and acquire the data.

Action Item: Resurrect this PR in QGC: Add NTRIP with VRS support by WTPENGUIN · Pull Request #10524 · mavlink/qgroundcontrol · GitHub

  • Conor can help with testing the PR of QGC as well
  • NTRIP is nice for wireless network bridging application
  • E.g. setting base station out for 2 min ~ 1 hr! To get accurate position use cases.
  • Andrew: Was pushing the NTRIP through MAVLink router, instead of going through QGC

Reference: RTK GPS | PX4 User Guide

Another Reference: https://github.com/mavlink/qgroundcontrol/pull/9493

Q.4 : Why is NMEA GPS protocol not implemented? - Sibu

Answer: There is support. But binary protocols from vendors are usually better to use.

Q.5 : VL5301LX Distance Sensor - Sibu

Collision prevention is not working.

Answer: The driver originally assumes the distance sensor is facing the ground. And having 1 sensor wouldn’t even be that effective.

Also, the flight mode needs to be set properly, otherwise it doesn’t work. Check out this thread: Discord

Reference: Collision Prevention | PX4 User Guide

Action Items: Having process into getting ‘supported sensors’ into the Doc (To avoid confusion for users) / specifying Release naming (‘main’ branch, etc)

:thinking: General Discussions

D.1 :

Github linkback bot test:

This was part of the initiative, related to the README update PR:

Test again, trying to trigger it! Changed repo name schema part

It worked: Update README: Maintainers, Boards, Roadmap by junwoo091400 · Pull Request #21030 · PX4/PX4-Autopilot · GitHub

1 Like

Px4 V1.14---------------> Just noticed that NMEA protocol is not listed in secondary GPS category under ( PARAM_DEFINE_INT32 (GPS_2_PROTOCOL, 1) but it is defined under GPS 1 Protocol. Was it missed or does it need to be addressed again .

thank you