QGC Actuators metadata unavailable with SDK 1.8 / PX4 1.18 through voxl-mavlink-server

[simiken1234]

Title: QGC Actuators metadata unavailable with SDK 1.8 / PX4 1.18 through voxl-mavlink-server

Hardware: Custom drone, VOXL 2 M0054
SKU: TF-M0054-4-V1-C11

Software version:

system-image: 1.8.09-M0054-14.1a-perf-20261009
hw platform:  M0054
voxl-suite:   1.8.0

Relevant packages:
voxl-px4            1.18.0-1.0.9
voxl-mavlink-server 1.4.20
voxl-px4-params     0.9.35

I can provide the full voxl-version output if needed.

Configuration / services:

voxl-px4 and voxl-mavlink-server are both enabled and running.

voxl-mavlink-server | Enabled | Running
voxl-px4            | Enabled | Running

What I am trying to do:

Configure the vehicle in QGroundControl and access the PX4 Actuators setup page.

What actually happens:

The Actuators page is absent in both our QGC 5.1.5 build and stock QGC 5.2.0; QGC shows the legacy Motors page instead.

PX4 accepts the component-metadata request and these files exist:

/data/px4/etc/extras/component_general.json.xz
/data/px4/etc/extras/actuators.json.xz

PX4 is started with MAVLink FTP enabled (mavlink start -x).

However, voxl-mavlink-server receives MAVLink FTP open requests for the PX4 metadata files, but no file data is returned to the GCS:

[INFO] FTP opcode: 4
[INFO] FTP seq_number: 1
[INFO] FTP session: 0
[INFO] path request?
etc/extras/component_general.json.xz
Offset: 0

The same occurs for etc/extras/actuators.json.xz. QGC's component-metadata cache remains empty, so it cannot create the Actuators page.

Steps to reproduce:

1. Boot VOXL with the versions above.
2. Connect QGroundControl to voxl-mavlink-server on UDP port 14550.
3. Open Vehicle Setup.
4. Observe that Actuators is absent.
5. Run journalctl -b -u voxl-mavlink-server and observe FTP opcode 4 requests for etc/extras/component_general.json.xz.

Logs / pictures:

I can attach full voxl-version, voxl-inspect-services, and relevant voxl-mavlink-server journal output.

Could you confirm whether voxl-mavlink-server 1.4.20 is expected to forward PX4-targeted FILE_TRANSFER_PROTOCOL requests for component metadata, or whether there is a newer package/fix for PX4 1.18 component metadata support?

[Eric Katzfey]

Thanks! Looking at some possible resolutions now.