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  3. Motor issues when running ESC calibration

Motor issues when running ESC calibration

Scheduled Pinned Locked Moved ESCs
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  • rdjarvisR rdjarvis

    @Alex-Kushleyev I am going to upload FPV_REVB. unless you recommend another.

    RDJ

    Alex KushleyevA Offline
    Alex KushleyevA Offline
    Alex Kushleyev
    ModalAI Team
    wrote on last edited by
    #90

    @rdjarvis , yes but change the vbatt since fpv revb is 6s. That is probably closest to your config

    rdjarvisR 1 Reply Last reply
    0
    • Alex KushleyevA Alex Kushleyev

      @rdjarvis , i wonder if you should try to load params for one of modalai standard vehicles and change the min/max rpm to match your setup (4000min, 40000 max, or you can be a bit more conservative, say 30k max for this test). Then try with manual control but with propellers OFF. The issue you are seeing is coming from Flight Controller so it should not matter of props are on or off for this test. But you should keep them off if using params from a completely different vehicle / tune. But at least you could then see if FC lets you raise the thrust normally..

      Basically, no change to esc, props off, choose our standard vehicle params for 4s and try to raise thrust, check the px4 log.

      If you see strange behavior like strong oscillations, you should stop the test.

      If the thrust control is ok, then you can compare your params more carefully with our standard params and see what causes this behavior.

      rdjarvisR Offline
      rdjarvisR Offline
      rdjarvis
      Regular
      wrote on last edited by
      #91

      @Alex-Kushleyev

      What effect does the aO,a1, and a2 (pwm_vs_rpm curve) have on overall throttle response for FPV 4n1 ESC? in the FPV_RevB the a0 value is -161.0826?

      Alex KushleyevA 1 Reply Last reply
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      • Alex KushleyevA Alex Kushleyev

        @rdjarvis , yes but change the vbatt since fpv revb is 6s. That is probably closest to your config

        rdjarvisR Offline
        rdjarvisR Offline
        rdjarvis
        Regular
        wrote on last edited by
        #92

        @Alex-Kushleyev

        Also, sinusodial value is 0 in FBV_RevB, I will change this to 1.

        1 Reply Last reply
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        • rdjarvisR rdjarvis

          @Alex-Kushleyev

          What effect does the aO,a1, and a2 (pwm_vs_rpm curve) have on overall throttle response for FPV 4n1 ESC? in the FPV_RevB the a0 value is -161.0826?

          Alex KushleyevA Offline
          Alex KushleyevA Offline
          Alex Kushleyev
          ModalAI Team
          wrote on last edited by
          #93

          @rdjarvis , please do not change ESC params that you tuned for your motors. I meant use px4 params from another vehicle.

          The a0.,1,2 are params for feed forward term in rpm control. The esc seems to be working fine in your case (rpm tracking is good).

          rdjarvisR 1 Reply Last reply
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          • Alex KushleyevA Alex Kushleyev

            @rdjarvis , please do not change ESC params that you tuned for your motors. I meant use px4 params from another vehicle.

            The a0.,1,2 are params for feed forward term in rpm control. The esc seems to be working fine in your case (rpm tracking is good).

            rdjarvisR Offline
            rdjarvisR Offline
            rdjarvis
            Regular
            wrote on last edited by
            #94

            @Alex-Kushleyev

            copy all, will do.

            Alex KushleyevA 1 Reply Last reply
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            • rdjarvisR rdjarvis

              @Alex-Kushleyev

              copy all, will do.

              Alex KushleyevA Offline
              Alex KushleyevA Offline
              Alex Kushleyev
              ModalAI Team
              wrote on last edited by Alex Kushleyev
              #95

              @rdjarvis , sorry for confusion, please do not change esc params but find px4 tuning params for our fpv vehicle and try to load it to your vehicle (change 6s vbatt to 4s in px4 params since fpv vehicle uses 6s).

              Test without props because attitude control is going tonbe much different for fpv vehicles vs yours. But you should still be able yo see thrust response in plots.

              Alex KushleyevA 1 Reply Last reply
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              • Alex KushleyevA Alex Kushleyev

                @rdjarvis , sorry for confusion, please do not change esc params but find px4 tuning params for our fpv vehicle and try to load it to your vehicle (change 6s vbatt to 4s in px4 params since fpv vehicle uses 6s).

                Test without props because attitude control is going tonbe much different for fpv vehicles vs yours. But you should still be able yo see thrust response in plots.

                Alex KushleyevA Offline
                Alex KushleyevA Offline
                Alex Kushleyev
                ModalAI Team
                wrote on last edited by
                #96

                you can find our FPV params here :

                Link Preview Image
                Files · master · voxl / VOXL SDK / Utilities / voxl-px4-params · GitLab

                PX4 parameter files for use on VOXL2 and Flight Core

                favicon

                GitLab (gitlab.com)

                rdjarvisR 4 Replies Last reply
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                • Alex KushleyevA Alex Kushleyev

                  you can find our FPV params here :

                  Link Preview Image
                  Files · master · voxl / VOXL SDK / Utilities / voxl-px4-params · GitLab

                  PX4 parameter files for use on VOXL2 and Flight Core

                  favicon

                  GitLab (gitlab.com)

                  rdjarvisR Offline
                  rdjarvisR Offline
                  rdjarvis
                  Regular
                  wrote on last edited by
                  #97

                  @Alex-Kushleyev

                  We kept the custom ESC config for the 2203.5, and uploaded px4 FPV_RevB_v4.

                  Motors are more responsive in all channels, Throttle channel still conducts a "ramp up", but more aggresively when RC Tx input is applied.

                  1 Reply Last reply
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                  • Alex KushleyevA Alex Kushleyev

                    you can find our FPV params here :

                    Link Preview Image
                    Files · master · voxl / VOXL SDK / Utilities / voxl-px4-params · GitLab

                    PX4 parameter files for use on VOXL2 and Flight Core

                    favicon

                    GitLab (gitlab.com)

                    rdjarvisR Offline
                    rdjarvisR Offline
                    rdjarvis
                    Regular
                    wrote on last edited by
                    #98

                    @Alex-Kushleyev No actionable response from throttle.

                    1 Reply Last reply
                    0
                    • Alex KushleyevA Alex Kushleyev

                      you can find our FPV params here :

                      Link Preview Image
                      Files · master · voxl / VOXL SDK / Utilities / voxl-px4-params · GitLab

                      PX4 parameter files for use on VOXL2 and Flight Core

                      favicon

                      GitLab (gitlab.com)

                      rdjarvisR Offline
                      rdjarvisR Offline
                      rdjarvis
                      Regular
                      wrote on last edited by
                      #99

                      @Alex-Kushleyev

                      Throttle input is being "ignored" regardless of RC Channel input, same response (slow ramp up) when armed in any flight mode (Manual/Stab/Pos etc..) and throttle is increased, even when RC Channel is changed (1,2,3,4).

                      Motors respond correctly with pitch, yaw, and roll inputs.

                      PX4 FPV_RevBv4 params are uploaded, switched to 4S and put min/max RPM to 3000/40000.

                      1 Reply Last reply
                      0
                      • Alex KushleyevA Alex Kushleyev

                        you can find our FPV params here :

                        Link Preview Image
                        Files · master · voxl / VOXL SDK / Utilities / voxl-px4-params · GitLab

                        PX4 parameter files for use on VOXL2 and Flight Core

                        favicon

                        GitLab (gitlab.com)

                        rdjarvisR Offline
                        rdjarvisR Offline
                        rdjarvis
                        Regular
                        wrote on last edited by
                        #100

                        @Alex-Kushleyev

                        From the GCS, executed "take-off" command in "Position Mode" with props off. Motors smoothly increase. I "hand-flew" it up to 1m and UAV was adjusting for small movements correctly.

                        Executed "Land" and "hand-flew" it to the deck, landing detected and disarmed.

                        Alex KushleyevA 1 Reply Last reply
                        0
                        • rdjarvisR rdjarvis

                          @Alex-Kushleyev

                          From the GCS, executed "take-off" command in "Position Mode" with props off. Motors smoothly increase. I "hand-flew" it up to 1m and UAV was adjusting for small movements correctly.

                          Executed "Land" and "hand-flew" it to the deck, landing detected and disarmed.

                          Alex KushleyevA Offline
                          Alex KushleyevA Offline
                          Alex Kushleyev
                          ModalAI Team
                          wrote on last edited by
                          #101

                          @rdjarvis , interesting. Can you please share a px4 log from that position mode test?

                          rdjarvisR 1 Reply Last reply
                          0
                          • Alex KushleyevA Alex Kushleyev

                            @rdjarvis , interesting. Can you please share a px4 log from that position mode test?

                            rdjarvisR Offline
                            rdjarvisR Offline
                            rdjarvis
                            Regular
                            wrote on last edited by
                            #102

                            @Alex-Kushleyev
                            https://review.px4.io/plot_app?log=f154b563-aa6e-4ff8-b603-67b9b6e2e64c

                            Alex KushleyevA 1 Reply Last reply
                            0
                            • rdjarvisR rdjarvis

                              @Alex-Kushleyev
                              https://review.px4.io/plot_app?log=f154b563-aa6e-4ff8-b603-67b9b6e2e64c

                              Alex KushleyevA Offline
                              Alex KushleyevA Offline
                              Alex Kushleyev
                              ModalAI Team
                              wrote on last edited by
                              #103

                              @rdjarvis , yes in this mode, the vehicle seems to be responding to thrust commands and motors are tracking rpm well (even though without props)

                              c7f8c2c5-85b1-429d-9df6-d60bdfaf19a5-image.png

                              rdjarvisR 1 Reply Last reply
                              0
                              • Alex KushleyevA Alex Kushleyev

                                @rdjarvis , yes in this mode, the vehicle seems to be responding to thrust commands and motors are tracking rpm well (even though without props)

                                c7f8c2c5-85b1-429d-9df6-d60bdfaf19a5-image.png

                                rdjarvisR Offline
                                rdjarvisR Offline
                                rdjarvis
                                Regular
                                wrote on last edited by
                                #104

                                @Alex-Kushleyev I agree, what do you think the next troubleshooting step is for this issue?

                                Alex KushleyevA 1 Reply Last reply
                                0
                                • rdjarvisR rdjarvis

                                  @Alex-Kushleyev I agree, what do you think the next troubleshooting step is for this issue?

                                  Alex KushleyevA Offline
                                  Alex KushleyevA Offline
                                  Alex Kushleyev
                                  ModalAI Team
                                  wrote on last edited by Alex Kushleyev
                                  #105

                                  @rdjarvis ,

                                  Also another observation.. remember in manual flight, it seemed like instead of responding to the throttle stick, the actuator outputs were going up slowly in a ramp -- i just double check that seems to be a response to small rill/pitch deviations that happened, so it seems that the thrust stick is COMPLETELY ignored, which is what you have suggested.

                                  Now, the position mode goes through the same control pipeline except the hight is controlled using a high controller, as opposed to your radio. However, the commands are still going through the mixer that converts and thrust, roll, pitch, yaw commands to motor outputs , so that seems to be working correctly.

                                  Based on that, it seems the issue is somewhere between the Actuator controls and motor outputs, which is the mixer, right? Actuator controls data shows the desired thrust (up) goes up, but motor output does not reflect this. Maybe we can look at the px4 source code for the mixer which maps the actuator controls to motor outputs.

                                  I just noticed that you have parameters CA_ROTORx_AZ (for x =0,1,2,3) set to 1, but default is -1, which would mean that you are saying that thrust from this motor goes up, not down?

                                  rdjarvisR 1 Reply Last reply
                                  0
                                  • Alex KushleyevA Alex Kushleyev

                                    @rdjarvis ,

                                    Also another observation.. remember in manual flight, it seemed like instead of responding to the throttle stick, the actuator outputs were going up slowly in a ramp -- i just double check that seems to be a response to small rill/pitch deviations that happened, so it seems that the thrust stick is COMPLETELY ignored, which is what you have suggested.

                                    Now, the position mode goes through the same control pipeline except the hight is controlled using a high controller, as opposed to your radio. However, the commands are still going through the mixer that converts and thrust, roll, pitch, yaw commands to motor outputs , so that seems to be working correctly.

                                    Based on that, it seems the issue is somewhere between the Actuator controls and motor outputs, which is the mixer, right? Actuator controls data shows the desired thrust (up) goes up, but motor output does not reflect this. Maybe we can look at the px4 source code for the mixer which maps the actuator controls to motor outputs.

                                    I just noticed that you have parameters CA_ROTORx_AZ (for x =0,1,2,3) set to 1, but default is -1, which would mean that you are saying that thrust from this motor goes up, not down?

                                    rdjarvisR Offline
                                    rdjarvisR Offline
                                    rdjarvis
                                    Regular
                                    wrote on last edited by
                                    #106

                                    @Alex-Kushleyev Thanks Alex, We will test it out. In the meantime my team will be sending the first FPV 4n1 ESC back, so you can investigate onsite.

                                    Thank you,
                                    RDJ

                                    Alex KushleyevA 1 Reply Last reply
                                    0
                                    • rdjarvisR rdjarvis

                                      @Alex-Kushleyev Thanks Alex, We will test it out. In the meantime my team will be sending the first FPV 4n1 ESC back, so you can investigate onsite.

                                      Thank you,
                                      RDJ

                                      Alex KushleyevA Offline
                                      Alex KushleyevA Offline
                                      Alex Kushleyev
                                      ModalAI Team
                                      wrote on last edited by
                                      #107

                                      @rdjarvis , please let me know the RMA number once you send back the M0138 ESC. Thanks!

                                      Alex KushleyevA 1 Reply Last reply
                                      0
                                      • Alex KushleyevA Alex Kushleyev

                                        @rdjarvis , please let me know the RMA number once you send back the M0138 ESC. Thanks!

                                        Alex KushleyevA Offline
                                        Alex KushleyevA Offline
                                        Alex Kushleyev
                                        ModalAI Team
                                        wrote on last edited by
                                        #108

                                        @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

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