ModalAI Forum

@Eric-Katzfey
I'm not sure what may have changed, before when setting BATT_MONITOR to 21 the param would write but we wouldn't get the additional parameters that that setting should have enabled. Last week I tried it again to reply to your last message and we got the BATT_I2C_BUS parameter and were able to get it all working. Gotta love when things seem to magically fix themselves, thanks for the support.

PS, we have built a parallel system on the latest SDK and will be migrating the current one over to match.

@Eric-Katzfey I finally had an opportunity to try a different power board but we still do not have any battery_status topic. We will look at updating the SDK but don't want to derail our CV development doing so. I'd prefer to find a solution without having to do that.

@Eric-Katzfey
We will look into updating the sdk, but that's always a fair bit of work.

@Eric-Katzfey

I don't see any battery_status message

@Eric-Katzfey
We're on voxl-ardupilot 4.8.0-325875bb

I've been connecting through mission planner, but have not been able to get any battery data. Looked through mavlink inspector and there is no battery_status topic.

Hi I'm using the M0041 board to power our voxl2 running ardupilot and having difficulty configuring the battery monitor. I found this post but we do not have the BATT_I2C_BUS parameter to set.

When checking voxl-inspect-battery, we only get the headers, no data. Voxl-vision-hub is running.

voxl-version
────────────────────────────────────────────────────────────────────────────────
system-image: 1.8.04-M0054-14.1a-perf
kernel:       #1 SMP PREEMPT Mon Mar 24 22:31:58 UTC 2025 4.19.125
────────────────────────────────────────────────────────────────────────────────
hw platform:  M0054
mach.var:     1.0.1
SKU:          MCCA-M0054-C11-T0-M0-X0
────────────────────────────────────────────────────────────────────────────────
voxl-suite:   1.5.0
────────────────────────────────────────────────────────────────────────────────
Packages:
Repo:  http://voxl-packages.modalai.com/ ./dists/qrb5165/sdk-1.5/binary-arm64/
Last Updated: 2026-03-18 01:43:20
List:
libfc-sensor                1.0.7
libmodal-cv                 0.5.18
libmodal-exposure           0.1.4
libmodal-journal            0.2.6
libmodal-json               0.4.7
libmodal-pipe               2.13.2
libqrb5165-io               0.5.0
libvoxl-cci-direct          0.3.3
libvoxl-cutils              0.1.5
modalai-slpi                1.2.0
mv-voxl                     0.1-r0
qrb5165-bind                0.1-r0
qrb5165-dfs-server          0.2.0
qrb5165-imu-server          1.1.3
qrb5165-mini-tof-server     0.2.2
qrb5165-rangefinder-server  0.1.5
qrb5165-slpi-test-sig       01-r0
qrb5165-system-tweaks       0.3.6
qrb5165-tflite              2.8.0-2
voxl-ardupilot              4.8.0-325875bb
voxl-bind-spektrum          0.1.1
voxl-camera-calibration     0.6.0
voxl-camera-server          2.2.4
voxl-ceres-solver           2:1.14.0-10
voxl-configurator           1.0.2
voxl-cpu-monitor            0.6.0
voxl-docker-support         1.3.1
voxl-elrs                   0.4.7
voxl-esc                    1.5.4
voxl-feature-tracker        0.5.2
voxl-flow-server            0.3.6
voxl-gphoto2-server         0.0.10
voxl-joystick-server        0.0.6
voxl-jpeg-turbo             2.1.3-7
voxl-lepton-server          1.3.3
voxl-lepton-tracker         0.0.4
voxl-libgphoto2             0.0.4
voxl-libuvc                 1.0.7
voxl-logger                 0.5.3
voxl-mavcam-manager         0.6.0
voxl-mavlink                0.1.5
voxl-mavlink-server         1.4.9
voxl-modem                  1.1.8
voxl-mongoose               7.7.0-2
voxl-mpa-to-ros             0.3.9
voxl-mpa-tools              1.4.0
voxl-open-vins              0.4.19
voxl-open-vins-server       0.3.12
voxl-opencv                 4.5.5-3
voxl-osd                    0.1.8
voxl-portal                 0.7.11
voxl-px4                    1.14.0-2.0.105
voxl-px4-params             0.7.5
voxl-qvio-server            1.2.0
voxl-remote-id              0.0.9
voxl-reset-slpi             0.0.1
voxl-state-estimator        0.0.5
voxl-streamer               0.7.5
voxl-suite                  1.5.0
voxl-tag-detector           0.0.5
voxl-tflite-server          0.4.1
voxl-utils                  1.4.8
voxl-uvc-server             0.1.7
voxl-vision-hub             1.8.23
voxl-vtx                    1.4.7
voxl-wavemux                0.0.1
voxl2-io                    0.0.3
voxl2-system-image          1.8.04-r0
voxl2-wlan                  1.0-r0

@Vinny Is J8 still not supported? I'm looking at using a hadron and two M0166 sensors, which may not be possible without J8.

@Alex-Kushleyev
This was a first flight after a completely new flash. Unfortunately a package install failed and we had to unbrick before we had an opportunity to backup the PX4 params. The hover thrust was still in the process of training. We were also flying light because we've had so many issues with the system that we didn't want to risk the payload until we had confidence in the system. A mock payload weight would have helped here.

However that doesn't excuse the awful PX4 programming, not having a catch if the drone starts to fall, a default min xy of 1.5m/s, etc. We've shelved the system and will be using an ardupilot controller until we have time to develop the voxl at a slower pace.

@Alex-Kushleyev still pending on this. Have had other issues to solve. Will be starting another thread shortly.

@Alex-Kushleyev
Yes, ESC is working, we're able to calibrate ESCs using esc tools, spin up motors in QGC, and have flown several times. Just having to be very conservative without battery status.

@Alex-Kushleyev
Thank you for the instructions, I will look into those tomorrow.

We have the ESC plugged into Voxl2 J18 as indicated in the VOXL2 ESC configs

Low KV guidance is very welcome. We were having trouble getting the motors to work and looked into the param files to try and figure out what was wrong. Changing the KV made motor response much better. We have good motor behavior now but I'll go through those instructions to be sure the motors are properly tuned.

To add a bit more info;

ESC is connected to VOXL2 J18 and J4
VOXLIO is connected to VOXL2 J19 pins 9-12

Doodle Labs Dev port is connected to 5G carrier board J12
mRo Zed F9p is connected to 5G carrier board J9

If this is just a configuration issue where we need to point voxl or px4 to a different port I'd love to learn how.

@Alex-Kushleyev Yes thank you, we will be going through all of the calibrations as our application is completely custom.

@Alex-Kushleyev
The ESC came with the 4-pin UART cable for data to the ESC but nothing for power. That's it.