@yardy In order to update the kernel variant without re-installing the whole SDK, please follow these instructions:

cd <voxl-sdk-release>/system-image # reboot voxl2 into fastboot mode adb reboot bootloader # flash VOXL2 kernel variant 0 fastboot flash boot_a m0054-1-var00.0-kernel.img fastboot flash boot_b m0054-1-var00.0-kernel.img fastboot reboot # OR flash VOXL2 kernel variant 1 fastboot flash boot_a m0054-1-var00.1-kernel.img fastboot flash boot_b m0054-1-var00.1-kernel.img fastboot reboot

You can also test the kernel without overwriting it (the original kernel will be retained after voxl2 reboot:

adb reboot bootloader fastboot boot m0054-1-var00.0-kernel.img # OR fastboot boot m0054-1-var00.1-kernel.img

The latter method is useful when you are not sure if the kernel you are about to try actually works (when you are experimenting with building your own kernel) - you can try the new kernel without the risk of temporarily bricking your board.

Alex

@zauberflote1 @James-Strawson

I am attaching an issue i am facing, the drone is stable in a mat, but as soon as i bring it back i loses the position and drifts out and goes crazy when i try to give pilot input

INFO] world : 1.000000 1.000000 (2) ERROR in insert_data, detected timestamp out of order ov, 1440558439657 vs 1440591773303 ERROR in insert_data, detected timestamp out of order ov, 1456191779391 vs 1456191779391 ERROR in insert_data, detected timestamp out of order ov, 1460758438920 vs 1460791771472 ERROR in insert_data, detected timestamp out of order ov, 1461691774910 vs 1461691774910 ERROR in insert_data, detected timestamp out of order ov, 1461858441212 vs 1461858441212 ERROR in insert_data, detected timestamp out of order ov, 1462091774232 vs 1462125109024 ERROR in insert_data, detected timestamp out of order ov, 1462258438295 vs 1462291773555 ERROR in insert_data, detected timestamp out of order ov, 1462491774024 vs 1462525106316 ERROR in insert_data, detected timestamp out of order ov, 1462658436524 vs 1462725109597 ERROR in insert_data, detected timestamp out of order ov, 1462825106628 vs 1462891775690 ERROR in insert_data, detected timestamp out of order ov, 1462991771420 vs 1463058439440 ERROR in insert_data, detected timestamp out of order ov, 1464125106211 vs 1464125106211 ERROR in insert_data, detected timestamp out of order ov, 1464291773919 vs 1464291773919 ERROR in insert_data, detected timestamp out of order ov, 1464458441002 vs 1464458441002 ERROR in insert_data, detected timestamp out of order ov, 1464691773398 vs 1464725105273 ERROR in insert_data, detected timestamp out of order ov, 1465425110585 vs 1465558437773 ERROR in insert_data, detected timestamp out of order ov, 1465658438450 vs 1465825104596 ERROR in insert_data, detected timestamp out of order ov, 1465925106418 vs 1466091986731 ERROR in insert_data, detected timestamp out of order ov, 1466091986731 vs 1466225109387 ERROR in insert_data, detected timestamp out of order ov, 1466258441991 vs 1466391773450 ERROR in insert_data, detected timestamp out of order ov, 1467658442251 vs 1467691776314 ERROR in insert_data, detected timestamp out of order ov, 1470658438812 vs 1470658438812 ERROR in insert_data, detected timestamp out of order ov, 1470791773187 vs 1470858439698 ERROR in insert_data, detected timestamp out of order ov, 1470958439854 vs 1471025104073 ERROR in insert_data, detected timestamp out of order ov, 1471125105010 vs 1471191771000 ERROR in insert_data, detected timestamp out of order ov, 1471325106781 vs 1471358439125 ERROR in insert_data, detected timestamp out of order ov, 1471491772927 vs 1472058437406 ERROR in insert_data, detected timestamp out of order ov, 1471658438604 vs 1472225105843 ERROR in insert_data, detected timestamp out of order ov, 1471791775375 vs 1472225105843 ERROR in insert_data, detected timestamp out of order ov, 1471958440114 vs 1472425105999 ERROR in insert_data, detected timestamp out of order ov, 1472125105427 vs 1472592004124 ERROR in insert_data, detected timestamp out of order ov, 1472291774385 vs 1472758439489 ERROR in insert_data, detected timestamp out of order ov, 1472491771728 vs 1472925109124 waiting for enough clone states (1 of 5).... waiting for enough clone states (2 of 5).... waiting for enough clone states (3 of 5).... waiting for enough clone states (4 of 5).... ERROR in insert_data, detected timestamp out of order ov, 1474458439176 vs 1474458439176 ERROR in insert_data, detected timestamp out of order ov, 1474858440061 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1474891775321 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1474925109957 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1474958443290 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1474991770946 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1475025106050 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1475058439748 vs 1475625107196 [WARN] Motion detected, going to full processing ERROR in insert_data, detected timestamp out of order ov, 1475091775165 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1475125106571 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1475158441363 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1475191774279 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1475225106988 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1475258438550 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1475291774540 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1475325106311 vs 1475625107196 ERROR in insert_data, detected timestamp out of order ov, 1475458439384 vs 1477225106518 ERROR in insert_data, detected timestamp out of order ov, 1475491771415 vs 1477225106518 ERROR in insert_data, detected timestamp out of order ov, 1475691776883 vs 1477558441674 ERROR in insert_data, detected timestamp out of order ov, 1475725110738 vs 1477558441674 ERROR in insert_data, detected timestamp out of order ov, 1475758443863 vs 1477558441674 ERROR in insert_data, detected timestamp out of order ov, 1475791778446 vs 1477558441674 ERROR in insert_data, detected timestamp out of order ov, 1475825110321 vs 1477558441674 ERROR in insert_data, detected timestamp out of order ov, 1475858439383 vs 1477558441674 ERROR in insert_data, detected timestamp out of order ov, 1475891772613 vs 1477558441674 ERROR in insert_data, detected timestamp out of order ov, 1475925110581 vs 1477558441674 ERROR in insert_data, detected timestamp out of order ov, 1475958442873 vs 1477558441674 ERROR in insert_data, detected timestamp out of order ov, 1475991771154 vs 1477558441674 ERROR in insert_data, detected timestamp out of order ov, 1476291770633 vs 1478191770789 ERROR in insert_data, detected timestamp out of order ov, 1476325110946 vs 1478191770789 ERROR in insert_data, detected timestamp out of order ov, 1476358440894 vs 1478191770789 ERROR in insert_data, detected timestamp out of order ov, 1476392017456 vs 1478191770789 ERROR in insert_data, detected timestamp out of order ov, 1476425106258 vs 1478191770789 ERROR in insert_data, detected timestamp out of order ov, 1476458439956 vs 1478191770789 ERROR in insert_data, detected timestamp out of order ov, 1476491775894 vs 1478191770789 ERROR in insert_data, detected timestamp out of order ov, 1476525105946 vs 1478191770789 ERROR in insert_data, detected timestamp out of order ov, 1478325107247 vs 1480091772507 ERROR in insert_data, detected timestamp out of order ov, 1478358437924 vs 1480091772507 ERROR in insert_data, detected timestamp out of order ov, 1478391771674 vs 1480091772507 ERROR in insert_data, detected timestamp out of order ov, 1478425108653 vs 1480091772507 ERROR in insert_data, detected timestamp out of order ov, 1478458442768 vs 1480091772507 ERROR: invalid metadata, magic number=387521565, expected 1448040524 most likely client fell behind and pipe overflowed ERROR in insert_data, detected timestamp out of order ov, 1514291774160 vs 1514291774160 ERROR: features were 0 for a long time! cur: 1, min_req: 15 (are you bench testing?) [VIO_BAD_STATE] No Stable feature. WARNING auto-resetting, Bad VIO, State: true Q: -1 Vel: 1.738034 Uncert: 0.000915 State: 0(1) ERROR DIAGONAL WENT NEGATIVE ERROR DIAGONAL WENT NEGATIVE ERROR DIAGONAL WENT NEGATIVE ERROR DIAGONAL WENT NEGATIVE ERROR DIAGONAL WENT NEGATIVE ERROR DIAGONAL WENT NEGATIVE voxl-open-vins-server: /builds/voxl-public/voxl-sdk/third-party/voxl-open-vins/open_vins/ov_msckf/src/state/StateHelper.cpp:114: Assertion `!found_neg' failed. Aborted voxl2:~$ voxl-inspect-vins waiting for server at /run/mpa/ov_extended T_imu_wrt_vio (m) |Roll Pitch Yaw (deg)| state| error_code 0.00 0.00 0.00| -0.8 -2.7 0.0| OKAY | DROPPED_IMU voxl-open-vins-server disconnected T_imu_wrt_vio (m) |Roll Pitch Yaw (deg)| state| error_code 0.00 0.00 0.00| -0.9 -2.7 0.0| OKAY | ERROR validating EXT VIO t read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 4224 bytes, but it should be a multiple of 5268 0.00 0.00 0.00| -0.9 -2.7 0.0| OKAY | ERROR validating EXT VIO t read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 2112 bytes, but it should be a multiple of 5268 0.00 0.00 0.00| -0.9 -2.7 0.0| OKAY | ERROR validating EXT VIO t read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 2112 bytes, but it should be a multiple of 5268 -0.00 -0.00 0.00| -0.9 -2.8 0.0| OKAY | ERROR validating EXT VIO t read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 6336 bytes, but it should be a multiple of 5268 -0.00 -0.00 0.00| -0.9 -2.8 0.0| OKAY | ERROR validating EXT VIO t read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 2112 bytes, but it should be a multiple of 5268 -0.00 -0.00 0.00| -0.9 -2.8 0.0| OKAY | ERROR validating EXT VIO t read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 2112 bytes, but it should be a multiple of 5268 -0.00 -0.00 0.00| -0.9 -2.8 0.0| OKAY | ERROR validating EXT VIO t read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 7380 bytes, but it should be a multiple of 5268 -0.00 -0.00 0.00| -0.9 -2.8 0.0| OKAY | ERROR validating EXT VIO t read 8424 bytes, but it should be a multiple of 5268 ERROR validating EXT VIO data received through pipe: read partial packet read 7380 bytes, but it should be a multiple of 5268 4.38 -1.43 1.78| -1.6 19.3 -4.9| OKAY | voxl-open-vins-server disconnected ERROR in pipe_client_open opening request pipe: No such device or address Most likely the server stopped without cleaning up Client is cleaning up pipes for the server

@ashwin

Do you need to be able to control the servo from PX4 or it would be acceptable to have an API you could use on the CPU / Linux on VOXL2 ?

Alex

@Jetson-Nano , 60C is not an issue for embedded devices (throttling limit is around 95C, at which point the CPU will start reducing frequency to avoid overheating).

However, you mention that the temperature can reach 90C. Please note that the camera server itself most likely is not the main cause of the CPU temperature, but the consumers of the image frames may be using significant CPU.

You should identify the main causes of temperature rise by looking at output of top to see rough cpu usage of each process, but also try disabling mapper or openvins or hires image processing (if any).

Also, without any cooling, it is not a surprise that VOXL2 could overheat if its cpu / gpu load is very high. The SoC cannot run without cooling at full power. Airflow during flight usually provides significant cooling and you can manage the system load when not in flight or add cooling for stationary use cases (lack of air flow from propellers),

Alex

@h3robotics

The M0159 has been replaced by M0202, which has identical functionality but slightly smaller outline to fit the Hadron better. M0202 will be officially available shortly.

Here are the CAD files:
M0181
M0202

Alex

@Yufei-Jiang And I used voxl-configure-cameras and voxl-configure-extrinsics D0006_Sentinel to generate the camera config.

@george-kollamkulam That port is internally connected to the 5V coming from the main VOXL2 power (which is technically 5V 6A). Obviously you would be limited by the connector pins, which are rated around 1A max continuous. Also, drawing too much from this pin, can bring down the whole VOXL2 (if that 5V output on J19 is shorted to GND, for example).

@Jetson-Nano , please confirm the ESC is working by using a usb to serial connection directly to the esc and voxl-esc Python tools on a Linux PC or VM.

You can run simple commands to detect the esc and perform spin tests if needed, this is all documented.

https://docs.modalai.com/voxl-escs/faq/

If the esc is ok, then you will need to double check the FC v2 setup.

Alex

@Alex-Kushleyev @Moderator

@tom

I managed to get ADB working and have reinstalled the VOXL. I went for 1.1.2 version as wanted to see if previous issues i had with both 1.2.0 and 0.9.5 would be present. As of now I am able to ADB to the drone, as well as ssh, with it using the AP mode however my QGroundControl does not see the drone. I have changed within the voxl-mavlink-server.conf the secondary ip address to the one that PC has when connected to the drone IP, and the following services are running. But QGroundControl does not seem to see the connection.

These are the following commands and their outputs. The one VOXL version which worked the best on the VOXL 1 board was 0.9.5 but after updating and switching both between AP mode and connected to Wifi router, there is no responce to the connection. When checking messages send to QGC the terminal is stopped at the step of the screenshot.

Screenshot from 2025-06-05 14-27-27.png
Screenshot from 2025-06-05 14-45-16.png
Screenshot from 2025-06-05 14-46-00.png
Screenshot from 2025-06-05 14-46-45.png
Screenshot from 2025-06-05 14-49-23.png
Screenshot from 2025-06-05 14-50-21.png

I went through the setup process few times and am unsure what could be the issue or what to try next. The QGC version is v4.4.5
In case I can create new thread for this but been trying to get two Seeker drones operational.

Thank you for your time and assistance.

Sincerely

Adam Nekolny

@jbhines929 No problem, thanks for the patience!

@goswamid ,

Yes we do sell those parts. Please contact us via online form. https://www.modalai.com/pages/contact-us

The part number you will need is M10000524

Alex

@ashwin I don't have the info either but it's similar to VOXL2's weight which is 16g

@smiley , we made a small adjustment to the M0159 board to make it fit into the Hadron better (board outline). That was a small board re-spin (same functionality). Checking on the status..

Alex

Hello, @Stefan-Amundarain ,

Let's try to narrow this down. Can you reproduce the issue without flying?

When the issue occurs, does the camera server restart completely, or you only lose hires camera feed. I suggest running the test on the bench with voxl-camera-server running in foreground so you can easily see what's happening in real time.

Please try to reproduce on the bench all 3 cameras (hires, tracking, TOF) working with your Ark Flow board working as well, then you can just move the platform by hand, if needed, to cause the camera failure and investigate what:

voxl-camera-server outputs output of dmesg

We can go from there.

Also, can you please provide details how the ARK Flow is actually connected to VOXL2 (electrically) and also confirm that the issue does not happen at all without ARK Flow plugged in?

Also, using voxl-portal should not cause the camera server or the portal backend to get bogged down if your image is reasonable size (not full 4k image), but a small 720p is just fine.

You could view the 3 camera streams thru voxl portal during the test or just have the voxl-inspect-cam tool running and inspecting just the streams that you want (you can provide the streams to inspect as arguments to the tool, such as voxl-inspect-cam hires tracking_down tof_depth, etc. Either voxl-portal or voxl-inspect-cam should properly use the camera pipeline with all camera streaming, so that you can catch the fault.

Alex

@shivam-rana , if you have a few wifi adapters which are currently not detected by VOXL2, if you plug into a standard Linux machine and if they are detected, you should check with chipset is used on those adapters and we can see if that's available (but not currently compiled) option for the VOXL2 kernel. We can add some documentation to help you build your own test kernel with enabled module and see if that works.

The VOXL2 kernel build guide is here : https://docs.modalai.com/voxl2-kernel-build-guide/ but it does not explicitly state how to make modifications to enable additional components. For those folks who have built kernels before, this may be easy to do, but for the first time it could be very difficult to do the right thing, but the change could be very small (one line). So we can see if it's possible to enable the driver that you need, but there would be no guarantees about functionality, since it would be untested (by us).

Alex

@victochen , sounds good, feel free to ask more questions.

The 62A current draw (1.3KW!) for one motor is probably OK for motor to sustain for a short period of time, but my guess is that the motor itself would overheat pretty quickly. Unfortunately I could not find any test data about this particular motor, which is unusual.

If we knew the propeller's thrust vs rpm, you could estimate your hover power draw right from this calibration plot (knowing the weight of your drone).

In any case, after you do a short first flight, you should analyse the log data, if you are using PX4, you can use flight-review to view the PX4 logs. Additionally, we maintain our own version of the flight review analysis tool, which includes some VOXL2 specific updates including all the ESC data (commanded and actual rpms, etc). You can find the fork of flight-review and instructions how to use it locally on your machine here : https://github.com/modalai/px4-flight-review

The total current (as the FPV ESC does not measure the individual motor current), will be reported in the battery_status message in the PX4 log and is viewable using flight-review (there is a section for battery voltage / current).

Also just to give you an idea of M0138 performance (and you can reproduce these tests), here is a test of 4 2207 motors with 5x4x3 props, 6S battery, spinning at 25K RPM (in closed loop RPM control mode) with full airflow cooling of the ESC. You can see the the ESC temp(s) go up pretty quickly, but this particular test was pretty short, i think i did not want to cook the motors, since ESC temps were still fine. The ESC is pulling around 125-130A total in this test and the performance is stable. You will notice two temperature bands in the 4 temperature measurements because these temps are reported from different locations (the higher temps are from the MCU's built-in temp sensors, which run a bit hotter due to MCU power consumption) and the lower two temperature measurements are from dedicated temperature sensors located next to the Mosfets (top and bottom of board).

m0138_full_cooling_25000_rpm_8sec.png

voxl-esc tools provide the tools to perform this analysis on the bench pretty easily and find out how your propulsion system is stressed under different conditions. You can also get similar logs from flights / px4-logs for real use case analysis.

Finally, our ESC driver in px4 supports warning and critical temperature limits, which will send out warnings to QGC if those limits are reached. The limits are disabled by default, but you can enable them with params: https://github.com/modalai/px4-firmware/blob/voxl-dev/src/drivers/actuators/voxl_esc/voxl_esc_params.c#L238 . However, i am not 100% sure of the behavior of PX4 if ESC reports critical temps, it could enter some failsafe mode, or something like that - you should double check that, if you enable these warnings.

Alex