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ESCs, Sensors and Accessories

392 Topics 2.3k Posts

ESCs, image sensors, ToF and tracking cameras, Microhard and cellular modems, power modules, GPS and other add-on boards.

  • Motor issues when running ESC calibration

    Unsolved esc
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    Alex KushleyevA
    @rdjarvis , I received the M0138 ESC that you sent back (reported that you were unable to communicate with the ESC). The issue was that the baud rate in ESC params was set to 2.5Mbit instead of 250K by accident, so our auto-scan in ESC tools could not detect the ESC (and VOXL2 DSP does not support 2.5Mbit). We will fix this in future ESC firmware to prevent accidental setting of unsupported baud rates. Sorry about that. Alex
  • VOXL2: Adjusting bandwith of video streaming

    Unsolved image-sensor
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    Alex KushleyevA
    @H-AL , are you using voxl-camera-server to produce h264 / h265 stream or voxl-streamer, which is capable of accepting uncompressed frames and producing h264/h265 stream. voxl-streamer is also capable of taking a compressed stream from voxl-camera-server and exposing it via RTSP. Please clarify how you are setting up your streaming.. Thanks! Alex
  • Control two 4in1 VOXL ESCs with one Voxl 2 Mini

    Unsolved esc
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    M
    @Alex-Kushleyev This forum post can be considered resolved with this answer: https://forum.modalai.com/post/17782 Thanks for the update. Cheers!
  • Localization via Quectel 5G modem

    Unsolved cellular
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    Eric KatzfeyE
    @tahawaru We have never tried that. But according to the Quectel product documentation it seems like it should be possible. Of course you would need to attach a suitable GNSS antenna to it. And if you want to use that with PX4 then you would need to create a new driver for it.
  • NACK Received when updating voxl esc

    Unsolved esc
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    Alex KushleyevA
    @wilkinsaf , yes, you got it. By the way, you did not have to restore the old firmware, you could have just done this: ./voxl-esc-upload-firmware.py --firmware-baud-rate 57600 -f firmware/modalai_esc_firmware_m0117_1_v0_39_RC10_eb6fb500.bin --id 0 The following note does not really help, if you also have power connected to VOXL2.. WARNING: Specified ESC ID not detected; perform manual power cycle now However, if the ESC is connected to a PC, you can just power cycle the ESC and the the bootloader will start up and firmware update will being. Alex
  • Where are the VOXL ESC Tools on the VOXL 2?

    Unsolved esc
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    No one has replied
  • ToF v2 keeps crashing because of high temperature

    Unsolved image-sensor
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    M
    @Alex-Kushleyev Thanks! This is helpful. Definitely easier to overheat these than the last gen so good to have the specs on it.
  • Serial communication with Sierra Wireless EM9291

    Unsolved cellular
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    tomT
    @groupo em9191 should work for you
  • This topic is deleted!

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  • ToF v2 ground level error

    Unsolved image-sensor
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    ModeratorM
    @Gyeongmin-Kim We don't have any great insight at this point. Those sensors are new. It looks like you are seeing some ghosting. You could try different frame rates or exposure times to try and minimize the artifacts
  • M0117 ESC rough control

    Unsolved esc
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    Eric KatzfeyE
    @Aaky Should be fine. I fly with actual RC in HITL all the time.
  • Voxlio board Sbus lagging

    Unsolved
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    Eric KatzfeyE
    @Alex-Kushleyev The fix is available in this build: http://voxl-packages.modalai.com/dists/qrb5165/dev/binary-arm64/voxl-px4_1.14.0-2.0.77-202406051703_arm64.deb
  • Question About Installing Capacitors on ESCs for Testing

    Unsolved esc
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    Alex KushleyevA
    @restore , yeah, good plan..
  • VOXL 2 Mini & VOXL Mini 4-in-1 ESC Configuration for PWM Motor Control

    Unsolved esc
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    Alex KushleyevA
    @Jeremy-Frederick, can you specify which ESC you are asking about? The PWM pins on the ModalAI ESCs (which have the pwm signals on a connector or test pads) are bi-directional, and yes they could be used as PWM output. However, a firmware change is required and enabling PX4 to send out PWM signals is another change We were considering enabling this feature but it is not yet implemented. Can you please provide more information about your requirements? what type of PWM signal are you trying to send ? min/max range, update frequency, (is it one shot, or just preriodic) how often are you planning to update the value of this PWM signal? how many PWM signals do you need? what is the source for the control of PWM signal in your application (RC or something else?). The reason why I am asking, the ESC would need to receive a serial data packet from voxl_esc driver in px4, so somehow that pwm output information would need to enter the voxl_esc driver. Alex
  • Turning off ESC regenrative braking for calibration

    Unsolved esc
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    Alex KushleyevA
    @schew, Regenerative braking happens when you command the ESC to transition from a higher speed to a lower speed. Also, if brake_to_stop parameter is set to 1, the ESC will apply braking when it is commanded to stop (0 rpm or 0 power) or it times out. If the brake_to_stop parameter is set to 0, the ESC will not brake during stopping or time out, instead the motor will spin freely (coast) to a stop. So, brake_to_stop parameter does not affect normal operation and you should just keep that at zero, unless you REALLY need the motor to stop very fast when you disarm. (but then if you are connected to a power supply at that point, it can cause issues described here : https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-esc/-/blob/master/voxl-esc-tools/doc/regenerative_braking.md ) Turning off Regenerative Braking completely is possible on M0129 ESC, but it is not currently supported in the firmware. So, to answer your question, if you run the ESC calibration using voxl-calibrate-esc.py script (according to these instructions : https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-esc/-/blob/master/voxl-esc-tools/calibration.md), there will not be a regenerative braking event during this procedure (unless you set brake_to_stop to 1, see above). In the calibration procedure, the ESC is commanded to increase the applied power in small steps and at the end the commands from the script stop, so ESC times out and spins down. I have just run a test using a power supply (set to 12V) and modified calibration script, which shows voltage and current data after the calibration has finished. See plot below: [image: 1717037084592-ad88ce7f-2a54-48a5-96cb-970af729443a-image-resized.png] From the plot you can see that at t=12s, the test stops, the voltage (which was dipping during the test as current increased) comes back to 12V without overshoot and the current just drops to zero (does not become negative, which would be the case, if regenerative current was present). I have explained what will happen if you run the esc calibration procedure (in its current version) while using a power supply. However, you should not do any aggressive spin testing with a power supply, especially step tests, where the ESC is commanded to ramp up and then down. The reason why we do not recommend doing any testing with a power supply is that it is possible to forget that the ESC is plugged into the power supply (not battery) and start performing tests which can damage the ESC or power supply. If you start hitting the Power Supply's over-current limit, voltage may drop and there could be strange behavior and ESC could de-sync. You also need to ensure that the Power Supply can source enough current to perform the calibration. If needed, you can decrease the maximum power that is applied during calibration (using --pwm-max parameter) So, with all that being said.. We still do not recommend testing the ESC with a power supply. If you still choose to do it, it would be at your own risk and i suggest starting by limiting --pwm-max parameter to a low value, say 40-50 and looking at the plot to ensure all the data looks similar to the plot in the calibration doc. Then gradually increase the --pwm-max parameter to 60, 70, 80, 90, checking the plot each time. You could stop at 90 and use that calibration result. Alex
  • VOXL ESC not connecting

    Unsolved esc
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    No one has replied
  • ESC telemetry rate

    Unsolved esc
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    Alex KushleyevA
    @0x45 , each of the 4 ESCs sends back telemetry to PX4 at 1/4 of the update rate of PX4. On voxl2, the PX4 update rate is 800hz, so each ESC channel sends back telemetry at 200hz (round robin fashion). Only one of the four ESC channels actually measures current on the 4-in-1 mini and FPV ESCs, so you will have the current update (and hence the battery status) received at 200hz, but px4 is throttling publishing of battery status to 10hz. Alex
  • Hires IMX214 M0024-2 causing ADB to stop working

    Unsolved image-sensor
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    Alex KushleyevA
    @Jeremy-Frederick, that is great! Luckily (or by design ) the camera connector reversal is typically not fatal, but DO NOT push your luck, please . Technically, if damage occurs due to incorrect insertion of the camera connectors, this will void the warranty for the main board. Always verify connector orientation when changing camera configuration. Alex
  • ESCs calibration after propellers replacement

    Unsolved esc
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    Alex KushleyevA
    @iparra , There is no need to re-calibrate the ESC parameters if you replace the damaged motor and / or propeller with the identical parts. The ESC parameters are tuned to a motor/propeller type, not a specific motor / propeller unit. You can replace only the damaged components. If the flight feels more wobbly after you replaced the damaged propeller with new one, it is possible the remaining propellers are also damaged or bent, which is causing more vibration. Alex
  • Stereo Camera Orientation

    Unsolved image-sensor
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    Alex KushleyevA
    @Gary-Holmgren , camera server does not support rotating images by 90 degrees (or multiples of 90). You could do this yourself in your image processing application. If you mount the cameras rotated by 90 degrees (while keeping the baseline along the left-right direction of the drone), you would need to modify your extrinsics to account for this rotation. If you perform a stereo camera calibration in this rotated configuration, then the output of the stereo calibration should give you the baseline result between the cameras in the Y direction in the camera frame (as opposed to X direction in normal case). If you have a question about a specific configuration, please make a drawing that shows reference frames of the vehicle, imu, and both cameras and I can help you double check the extrinsics. Alex