PX4 Community Q&A: May 10, 2023

rroche · May 3, 2023, 5:00pm

May 10, 2023

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Agenda

Community Announcement
Community Q&A
General Discussions

Community Announcement

A.1 :

Community Q&A (No deep technical discussions)

Guideline for asking a Question

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

Q.1: VIO bridge alternative

github.com/PX4/PX4-Autopilot

Problem with VIO bridge

opened 01:58PM - 20 Apr 23 UTC

blax185

VIO question

Hi, I have a question about VIO. Is there any example of the VIO bridge ROS node… that provides a bridge between a camera and ROS? If yes for what version of firmware is it compatible with? Previously I was working with the older version of firmware ( with ekf2_aid_mask param) and Autherion VIO bridge. In the simulation drone was flying properly in the scenario with VIO and turned off GPS. My goal was flying the drone with VIO and missing temporary GPS signal which I couldn't achieve. After attending PX4 community Devcall about month ago I was trying to implement flying the with VIO and missing GPS with firmware (1.14.0beta with ekf2_ev_ctrl parameter).In the sitl simulation drone wasn't flying properly with VIO system. I think that there could be a problem with VIO bridge. After this week PX4 call I was recommended to create this github issue with my VIO problem. I am using 1.14.0beta - firmware version. Here is my rosgraph and frames. ![rosgraph](https://user-images.githubusercontent.com/60292200/233388621-89aa5cf0-e295-4d0b-a4c3-2363a6f390d3.png) ![frames](https://user-images.githubusercontent.com/60292200/233388645-720c13f4-721c-4230-80e8-b7468c2575f5.png) Thanks in advance for any help.

Auterion repo is now private, is there an alternative?

Answer: Post on discord & maybe people may know there!

Q.2: QGC customizing a function - Anthony

To export KML files? How to get started in modifying the QGC code?

Object detection use case: Requiring confidence parameter, etc.

Goal: Handle a specific file (e.g. KML) that is getting passed through. There’s a rectangular pattern. And want to have a function to generate KML file with certain parameters.

Answer: There’s “Polygon tools” code section. Farhang will answer in DM.

Q.3: How to suppress preflight check? - Farhang

Currently the disarmed PWM value equals failsafe PWM value. Leading to unintended failsafe trigger.

In Gazebo, it’s now hard to determine if vehicle is in failsafe mode via PWM output value. Starting from v1.12, the parachute package in SITL Gazebo isn’t working.

github.com/PX4/PX4-SITL_gazebo-classic

Parachute deployment does not appear to work

opened 12:46AM - 22 Jul 21 UTC

hamishwillee

bug

The instructions in https://docs.px4.io/master/en/simulation/gazebo.html#simulat…ed-parachute-flight-termination explain that you can simulate parachute deployment by first launching the simulator with: ``` make px4_sitl gazebo_if750a ``` Then force flight termination. I tested this by forcing an altitude safety geofence violation (set a low altitude ceiling and flew straight up). The flight termination happens - there are GCS notifications and the vehicle crashes. But there is no indication that a parachute is deployed. How would you know? Shouldn't we see something appear on the screen?

Action Item: Ping beat on discord about this