VOXL ESC FPV 4-in-1 with Built-in Power Module (MDK-M0138) Issues
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What software versions are you using? Can you please create a PX4 log and share that via https://logs.px4.io/? Since logging normally doesn't start until you arm the drone you can force the logger to start and stop. For example, from the adb shell you can use px4-logger on to start a log and then px4-logger off to stop the log. Can you also paste the outputs from the detect / scan? Also review this other post: https://forum.modalai.com/topic/4833/throttle-doesnt-work/7
@Eric-Katzfey Attached below. I misspoke, it appears detect fails.
Here is the link: PX4 Logs
voxl2-test-fixture (TF-M0054):/$ voxl-version ──────────────────────────────────────────────────────────────────────────────── system-image: 1.8.06-M0054-14.1a-perf kernel: #1 SMP PREEMPT Wed Oct 22 04:13:18 UTC 2025 4.19.125 ──────────────────────────────────────────────────────────────────────────────── hw platform: M0054 mach.var: 1.0.1 SKU: TF-M0054-4-V1-C11 ──────────────────────────────────────────────────────────────────────────────── voxl-suite: 1.6.3 ──────────────────────────────────────────────────────────────────────────────── Packages: Repo: http://voxl-packages.modalai.com/ ./dists/qrb5165/sdk-1.6/binary-arm64/ Last Updated: 2026-08-06 19:57:23 List: libfc-sensor 1.0.9 libmodal-cv 0.6.0 libmodal-exposure 0.1.4 libmodal-flow 1.0.3 libmodal-journal 0.2.7 libmodal-json 0.4.8 libmodal-pipe 2.14.11 libqrb5165-io 0.6.3 libvoxl-cci-direct 0.3.3 libvoxl-codec 0.0.2 libvoxl-cutils 0.1.6 modalai-slpi 1.2.2 mv-voxl 0.1-r0 qrb5165-bind 0.1-r0 qrb5165-dfs-server 0.2.0 qrb5165-mini-tof-server 0.2.2 qrb5165-rangefinder-server 0.1.6 qrb5165-slpi-test-sig 01-r0 qrb5165-tflite 2.17.2 voxl-bind-spektrum 0.1.1 voxl-camera-calibration 0.6.1 voxl-camera-server 2.2.19 voxl-ceres-solver 2:2.0.0-2 voxl-configurator 1.1.5 voxl-cpu-monitor 0.7.7 voxl-docker-support 1.3.1 voxl-elrs 1.1.0 voxl-esc 1.6.3 voxl-esptool 0.2.0 voxl-feature-tracker 0.5.2 voxl-flow-server 0.3.6 voxl-gphoto2-server 0.0.10 voxl-imu-server 2.0.1 voxl-io-server 0.0.8 voxl-jpeg-turbo 2.1.3-7 voxl-lepton-server 1.3.3 voxl-lepton-tracker 0.0.4 voxl-libgeographic 1.0.0 voxl-libgphoto2 0.0.4 voxl-libuvc 1.0.7 voxl-logger 0.6.1 voxl-mavcam-manager 0.6.0 voxl-mavlink 0.1.6 voxl-mavlink-server 1.4.14 voxl-modem 1.2.3 voxl-mongoose 7.19.0 voxl-mpa-to-ros 0.3.9 voxl-mpa-tools 1.5.6 voxl-nano-tracker 0.1.7 voxl-open-vins-server 0.6.0 voxl-opencv 4.5.5-3 voxl-osd 0.3.8 voxl-portal 0.8.7 voxl-px4 1.14.0-2.0.133 voxl-px4-params 0.9.0 voxl-qvio-server 1.2.3 voxl-remote-id 0.0.9 voxl-reset-slpi 0.0.1 voxl-state-estimator 0.0.6 voxl-streamer 0.8.0 voxl-suite 1.6.3 voxl-tag-detector 0.1.0 voxl-tflite-server 0.5.1 voxl-utils 2.0.2 voxl-uvc-server 0.1.7 voxl-vision-hub 1.9.21 voxl-vtx 2.0.2 voxl-wavemux 0.0.3 voxl2-io 0.0.3 voxl2-security-hardening-utls 1.0-r0 voxl2-system-image 1.8.06-r0 voxl2-wlan 1.0-r0 ────────────────────────────────────────────────────────────────────────────────voxl2-test-fixture (TF-M0054):/$ voxl-esc scan enabling bridge detected voxl-px4 is enabled Removed /etc/systemd/system/multi-user.target.wants/voxl-px4.service. detected voxl-px4 is running, stopping it now Sending kill slpi command! bridge enabled Detected Python version : 3.6.9 (default, May 22 2025, 20:54:22) [GCC 8.4.0] Found voxl-esc tools bin version: 1.10 VOXL Platform: QRB5165 INFO: Scanning for ESC firmware: /dev/slpi-uart-2, baud: 2000000 Sending library name request: libslpi_qrb5165_io.so Sending initialization request INFO: ESC(s) detected on port: /dev/slpi-uart-2, baud rate: 2000000, protocol: firmware INFO: ESC Information: INFO: --------------------- ID : 0 Board : version 42: ModalAi 4-in-1 ESC (M0138-1) UID : 0x203837304848570400440022 Firmware : version 39.25, hash a58f5f6f Bootloader : version 187, hash aad89d63 ID : 1 Board : version 42: ModalAi 4-in-1 ESC (M0138-1) UID : 0x203837304848570300310055 Firmware : version 39.25, hash a58f5f6f Bootloader : version 187, hash aad89d63 ID : 2 Board : version 42: ModalAi 4-in-1 ESC (M0138-1) UID : 0x2038373048485705003A003F Firmware : version 39.25, hash a58f5f6f Bootloader : version 187, hash aad89d63 ID : 3 Board : version 42: ModalAi 4-in-1 ESC (M0138-1) UID : 0x203837304848570400440025 Firmware : version 39.25, hash a58f5f6f Bootloader : version 187, hash aad89d63 --------------------- successfully pinged ESCs disabling bridge Sending kill slpi command! re-enabling voxl-px4 Created symlink /etc/systemd/system/multi-user.target.wants/voxl-px4.service → /etc/systemd/system/voxl-px4.service. restarting voxl-px4 bridge disabled voxl2-test-fixture (TF-M0054):/$ voxl-esc detect enabling bridge detected voxl-px4 is enabled Removed /etc/systemd/system/multi-user.target.wants/voxl-px4.service. detected voxl-px4 is running, stopping it now Sending kill slpi command! bridge enabled Received standard error event SNS_STD_ERROR_NOT_SUPPORTED Couldn't configure flight_controller sensor ERROR: fc_sensor_initialize failed ERROR: Failed to initialize slpi ERROR: Encountered error while initializing bus 12 [ERROR] No ESCs detected disabling bridge Sending kill slpi command! re-enabling voxl-px4 Created symlink /etc/systemd/system/multi-user.target.wants/voxl-px4.service → /etc/systemd/system/voxl-px4.service. restarting voxl-px4 bridge disabled EXITING VOXL-ESC WITH ERROR voxl2-test-fixture (TF-M0054):/$ -
@jbiscan21 , have you tried the actuator test feature in QGC? make sure to remove propellers for safety.
Also, as px4 starts up, the
voxl-escpx4 driver will detect the ESCs and print some information, similar to what the CLI tool does without PX4. You can run voxl-px4 in foreground and check.voxl-px4 -dAlex
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example of
voxl-px4driver output when runningvoxl-px4 -d:... Starting VOXL ESC driver INFO [qshell] Send cmd: 'voxl_esc start' INFO [muorb] [uORB] Marking DeviceNode(qshell_req) as advertised in process_remote_topic INFO [muorb] [qshell] qshell gotten: voxl_esc start INFO [muorb] [qshell] arg0 = 'voxl_esc' INFO [muorb] [qshell] arg1 = 'start' INFO [uORB] Advertising remote topic actuator_outputs INFO [muorb] [voxl_esc] Starting VOXL ESC driver INFO [muorb] [voxl_esc] Params: VOXL_ESC_CONFIG: 1 INFO [muorb] [voxl_esc] Params: VOXL_ESC_MODE: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_BAUD: 2000000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_FUNC1: 102 INFO [muorb] [voxl_esc] Params: VOXL_ESC_FUNC2: 103 INFO [muorb] [voxl_esc] Params: VOXL_ESC_FUNC3: 101 INFO [muorb] [voxl_esc] Params: VOXL_ESC_FUNC4: 104 INFO [muorb] [voxl_esc] Params: VOXL_ESC_SDIR1: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_SDIR2: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_SDIR3: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_SDIR4: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_PWR_MIN: 0.050000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_RPM_MIN: 2000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_RPM_MAX: 12000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_PERC: 90 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_DEAD: 20 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_EXPO: 35 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_MINF: 0.150000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_COSP: 0.990000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_VLOG: 1 INFO [muorb] [voxl_esc] Params: VOXL_ESC_PUB_BST: 1 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_WARN: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_OVER: 0 INFO [muorb] [voxl_esc] Params: GPIO_CTL_CH: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_CMD: 0 INFO [muorb] [qshell] Ok executing command: voxl_esc start INFO [muorb] [voxl_esc] Opening UART ESC device 2, baud rate 2000000 INFO [muorb] [voxl_esc] Successfully opened UART ESC device INFO [muorb] [voxl_esc] Detecting ESCs... INFO [muorb] [voxl_esc] ESC ID : 0 INFO [muorb] [voxl_esc] Board Type : 40: ModalAi 4-in-1 ESC (M0129-3) INFO [muorb] [voxl_esc] Unique ID : 0x2039333557555313000F0036 INFO [muorb] [voxl_esc] Firmware : version 39, hash 9c6233d6 INFO [muorb] [voxl_esc] Bootloader : version 184, hash 10bf24c8 INFO [muorb] [voxl_esc] Reply time : 735us INFO [muorb] [voxl_esc] VOXL_ESC: INFO [muorb] [voxl_esc] ESC ID : 1 INFO [muorb] [voxl_esc] Board Type : 40: ModalAi 4-in-1 ESC (M0129-3) INFO [muorb] [voxl_esc] Unique ID : 0x2039333557555313000F0032 INFO [muorb] [voxl_esc] Firmware : version 39, hash 9c6233d6 INFO [muorb] [voxl_esc] Bootloader : version 184, hash 10bf24c8 INFO [muorb] [voxl_esc] Reply time : 721us INFO [muorb] [voxl_esc] VOXL_ESC: INFO [muorb] [voxl_esc] ESC ID : 2 INFO [muorb] [voxl_esc] Board Type : 40: ModalAi 4-in-1 ESC (M0129-3) INFO [muorb] [voxl_esc] Unique ID : 0x2039333557555313000F0034 INFO [muorb] [voxl_esc] Firmware : version 39, hash 9c6233d6 INFO [muorb] [voxl_esc] Bootloader : version 184, hash 10bf24c8 INFO [muorb] [voxl_esc] Reply time : 104us INFO [muorb] [voxl_esc] VOXL_ESC: INFO [muorb] [voxl_esc] ESC ID : 3 INFO [muorb] [voxl_esc] Board Type : 40: ModalAi 4-in-1 ESC (M0129-3) INFO [muorb] [voxl_esc] Unique ID : 0x2039333557555313000F0038 INFO [muorb] [voxl_esc] Firmware : version 39, hash 9c6233d6 INFO [muorb] [voxl_esc] Bootloader : version 184, hash 10bf24c8 INFO [muorb] [voxl_esc] Reply time : 727us INFO [muorb] [voxl_esc] VOXL_ESC: INFO [muorb] [voxl_esc] Use extended rpm packet : 1 INFO [muorb] [voxl_esc] All ESCs successfully detected ... -
@jbiscan21 , have you tried the actuator test feature in QGC? make sure to remove propellers for safety.
Also, as px4 starts up, the
voxl-escpx4 driver will detect the ESCs and print some information, similar to what the CLI tool does without PX4. You can run voxl-px4 in foreground and check.voxl-px4 -dAlex
Hello, using the actuator sliders in QGC results in the same behavior. The motors just spin at the same constant (arming) speed. Here are the results of
voxl-px4 -dStarting VOXL ESC driver INFO [qshell] Send cmd: 'voxl_esc start' INFO [muorb] [uORB] Marking DeviceNode(qshell_req) as advertised in process_remote_topic INFO [muorb] [qshell] qshell gotten: voxl_esc start INFO [muorb] [qshell] arg0 = 'voxl_esc' INFO [muorb] [qshell] arg1 = 'start' INFO [uORB] Advertising remote topic actuator_outputs INFO [muorb] [voxl_esc] Starting VOXL ESC driver INFO [muorb] [voxl_esc] Params: VOXL_ESC_CONFIG: 1 INFO [muorb] [voxl_esc] Params: VOXL_ESC_MODE: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_BAUD: 2000000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_FUNC1: 101 INFO [muorb] [voxl_esc] Params: VOXL_ESC_FUNC2: 104 INFO [muorb] [voxl_esc] Params: VOXL_ESC_FUNC3: 102 INFO [muorb] [voxl_esc] Params: VOXL_ESC_FUNC4: 103 INFO [muorb] [voxl_esc] Params: VOXL_ESC_SDIR1: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_SDIR2: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_SDIR3: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_SDIR4: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_PWR_MIN: 0.050000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_RPM_MIN: 3000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_RPM_MAX: 30653 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_PERC: 90 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_DEAD: 20 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_EXPO: 35 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_MINF: 0.150000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_COSP: 0.990000 INFO [muorb] [voxl_esc] Params: VOXL_ESC_VLOG: 1 INFO [muorb] [voxl_esc] Params: VOXL_ESC_PUB_BST: 1 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_WARN: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_T_OVER: 0 INFO [muorb] [voxl_esc] Params: GPIO_CTL_CH: 0 INFO [muorb] [voxl_esc] Params: VOXL_ESC_CMD: 0 INFO [muorb] [qshell] Ok executing command: voxl_esc start INFO [muorb] [voxl_esc] Opening UART ESC device 2, baud rate 2000000 INFO [muorb] [voxl_esc] Successfully opened UART ESC device INFO [muorb] [voxl_esc] Detecting ESCs... INFO [muorb] [voxl_esc] ESC ID : 0 INFO [muorb] [voxl_esc] Board Type : 42: ModalAi 4-in-1 ESC (M0138-1) INFO [qshell] qshell return value timestamp: 299177998, local time: 299182990 INFO [muorb] [voxl_esc] Unique ID : 0x203837304848570400440022 INFO [muorb] [voxl_esc] Firmware : version 39, hash a58f5f6f INFO [muorb] [voxl_esc] Bootloader : version 187, hash aad89d63 INFO [muorb] [voxl_esc] Reply time : 709us INFO [muorb] [voxl_esc] VOXL_ESC: INFO [muorb] [voxl_esc] ESC ID : 1 INFO [muorb] [voxl_esc] Board Type : 42: ModalAi 4-in-1 ESC (M0138-1) INFO [muorb] [voxl_esc] Unique ID : 0x203837304848570300310055 INFO [muorb] [voxl_esc] Firmware : version 39, hash a58f5f6f INFO [muorb] [voxl_esc] Bootloader : version 187, hash aad89d63 INFO [muorb] [voxl_esc] Reply time : 724us INFO [muorb] [voxl_esc] VOXL_ESC: INFO [muorb] [voxl_esc] ESC ID : 2 Starting CRSF RC driver INFO [muorb] [voxl_esc] Board Type : 42: ModalAi 4-in-1 ESC (M0138-1) INFO [muorb] [voxl_esc] Unique ID : 0x2038373048485705003A003F INFO [muorb] [voxl_esc] Firmware : version 39, hash a58f5f6f INFO [muorb] [voxl_esc] Bootloader : version 187, hash aad89d63 INFO [muorb] [voxl_esc] Reply time : 716us INFO [muorb] [voxl_esc] VOXL_ESC: INFO [muorb] [voxl_esc] ESC ID : 3 INFO [muorb] [voxl_esc] Board Type : 42: ModalAi 4-in-1 ESC (M0138-1) INFO [muorb] [voxl_esc] Unique ID : 0x203837304848570400440025 INFO [muorb] [voxl_esc] Firmware : version 39, hash a58f5f6f INFO [muorb] [voxl_esc] Bootloader : version 187, hash aad89d63 INFO [muorb] [voxl_esc] Reply time : 706us INFO [muorb] [voxl_esc] VOXL_ESC: INFO [muorb] [voxl_esc] Use extended rpm packet : 1 INFO [muorb] [voxl_esc] All ESCs successfully detected INFO [uORB] Advertising remote topic actuator_outputs_debug INFO [uORB] Advertising remote topic esc_status -
@alex-kushleyev @eric-katzfey
One thing I noticed, if I changeESC Command Typefrom RPM to PWM in the actuators tab, then I can increase the motor speeds -
@jbiscan21 , can you also share the esc params that you uploaded to the ESC after ESC calibration ? I am assuming you went through this procedure : https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-esc/-/blob/master/voxl-esc-tools/calibration.md
From the log I see that all 4 motors spun up but the rpm is capped at about 2200 rpm, which may mean you ESC tuning params are incorrect.
Also note that after arming, your drone immediately commands about 10000 rpm, which is not great, because that would be a sudden jump.. you may want to check your flight mode to avoid this.
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Quick side questions @alex-kushleyev @eric-katzfey
Have you ever calibrated PWM control with these drones or is that not advised?
I am a bit confused on the RPM calibration process. It appears to me that the RPM control is closed loop, but one thing that does not make sense to me is the testing with props on. I understand that props on will simulate aerodynamic load for calibration but wouldn't the load be different in flight too? Or is the idea that props on calibration is closer to flight load than props off?
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@jbiscan21 , can you also share the esc params that you uploaded to the ESC after ESC calibration ? I am assuming you went through this procedure : https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-esc/-/blob/master/voxl-esc-tools/calibration.md
From the log I see that all 4 motors spun up but the rpm is capped at about 2200 rpm, which may mean you ESC tuning params are incorrect.
Also note that after arming, your drone immediately commands about 10000 rpm, which is not great, because that would be a sudden jump.. you may want to check your flight mode to avoid this.
@Alex-Kushleyev Yes I want through that procedure. Here are my params:
<?xml version="1.0" encoding="UTF-8"?> <!-- Copyright (c) 2020 ModalAI Inc. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. 4. The Software is used solely in conjunction with devices provided by ModalAI Inc. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. For a license to use on non-ModalAI hardware, please contact license@modalai.com --> <EscParameters> <IdParams> <param name="id" value="127"/> <!-- 0-7 .. 127 means use hardware ID pins to read ID--> <param name="dir" value="2"/> <!-- 0=fwd, 1=rev, 2=fwd id-based, 3=rev id-based --> </IdParams> <UartParams> <param name="protocol_version" value="2"/> <!-- reserved for future use --> <param name="input_mode" value="0"/> <!-- reserved for future use --> <param name="baud_rate" value="2000000"/> <!-- communication bit rate --> <param name="char_timeout_ns" value="0"/> <!-- not used --> <param name="cmd_timeout_ns" value="100000000"/> <!-- timeout for incoming commands before ESC will stop the motor --> </UartParams> <TuneParams> <param name="pwm_frequency" value="48000"/> <!-- switching freqency of PWM signal going to motors. 24Khz and 48Khz are only options for now --> <param name="vbat_nominal_mv" value="22200"/> <!-- used for sanity checking and limiting of voltage-dependent funcions --> <param name="num_cycles_per_rev" value="7"/> <!-- number of pole pairs in the motor. used for converting electrical frequency to mechanical rpm --> <param name="min_rpm" value="3020"/> <!-- WARNING: not tuned. minimum RPM that will be attempted, otherwise capped --> <param name="max_rpm" value="26311"/> <!-- WARNING: not tuned. maximum RPM that will be attempted, otherwise capped --> <param name="min_pwm" value="75"/> <!-- cap for minimum power to be ever applied. min is 75 --> <param name="max_pwm" value="9999"/> <!-- cap for maximum power to be ever applied. max is 999 --> <param name="pwm_vs_rpm_curve_a0" value="-92.6079829269"/> <!-- this is actually motor_voltage vs rpm curve.. using legacy naming --> <param name="pwm_vs_rpm_curve_a1" value="0.813657468926"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="pwm_vs_rpm_curve_a2" value="2.69099700436e-06"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="kp" value="0"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="ki" value="0"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="max_kpe" value="0"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="max_kie" value="0"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="max_rpm_delta" value="0"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="spinup_type" value="1"/> <!-- 0: traditional, 1: sinusoidal --> <param name="spinup_power" value="60"/> <!-- power used to during spin-up procedure --> <param name="latch_power" value="60"/> <!-- power used during latching stage of spin-up (out of 999)--> <param name="spinup_power_ramp" value="8"/> <!-- it will take ( 4096 / (spinup_power_ramp*10000) ) seconds to ramp sinusoidal start-up power from 0 to spinup_power --> <param name="spinup_rpm_target" value="2000"/> <!-- Desired RPM at the end of the sinusoidal spin-up procedure --> <param name="spinup_time_ms" value="500"/> <!-- Duration of the sinusoidal spin-up procedure --> <param name="spinup_bemf_comp" value="1"/> <!-- 0: disable, 1:enable back-emf compensation in sinusoidal spin-up procedure --> <param name="motor_kv" value="2300"/> <!-- kV value of the motor. used in back-emf compensation during spin-up --> <param name="min_num_cross_for_closed_loop" value="10"/> <!-- exit latching mode of fixed power after this number of zero crossings --> <param name="protection_stall_check_rpm" value="1000"/> <!-- if motor spins below this RPM, stall check will trigger and stop / restart the motor --> <param name="brake_to_stop" value="0"/> <!-- apply brake when stopping motor (or not) --> <param name="stall_timeout_ns" value="20000000"/> <!-- after spin-up, if no zero crossing is not detected for this amount of time, motor is considered stalled --> <param name="require_reset_if_stalled" value="0"/> <!-- require sending an array of zero commands to reset before next spin-up, if motor stalled --> <param name="tone_freqs" value="[200, 215, 225, 250, 0,0,0,0, 0,0,0,0]"/> <!-- 200 is 2000Hz, max 255 --> <param name="tone_durations" value="[3, 0, 0, 0, 0,0,0,0, 0,0,0,0]"/> <!-- duration of each tone in units of 10 milli-seconds. Poor naming!!! --> <param name="tone_powers" value="[20, 0, 0, 0, 0,0,0,0, 0,0,0,0]"/> <!-- max is 255 --> <param name="dt_threshold_ns" value="150000"/> <!-- during start up, ignore inter-commutation times less than this val, probably noise --> <param name="max_dt_ns" value="2500000"/> <!-- min and max values for time between two commutations. these are used as caps --> <param name="min_dt_ns" value="10000"/> <param name="dt_bootstrap_ns" value="2000000"/> <!-- filter bootstrap value for commutation dt during start up --> <param name="spinup_stall_dt_ns" value="6000000"/> <!-- during spin-up, if no zero crossing is not detected for this amount of time, motor is considered stalled --> <param name="spinup_stall_check_ns" value="30000000"/> <!-- time after beginning of spinup to start checking for spinup stall --> <param name="alignment_time_ns" value="0"/> <!-- alignment time before spin-up --> <param name="timing_advance" value="0"/> <param name="sense_advance" value="0"/> <param name="demag_timing" value="0"/> <!-- unused --> <param name="led_config" value="0"/> <!-- 0: enable status LEDs in bootloader and firmware, 1: disable LEDs in boot and firmware: 2: disable LEDs only in firmware. need FW 39.25 or later --> </TuneParams> </EscParameters> -
@Alex-Kushleyev Yes I want through that procedure. Here are my params:
<?xml version="1.0" encoding="UTF-8"?> <!-- Copyright (c) 2020 ModalAI Inc. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. 4. The Software is used solely in conjunction with devices provided by ModalAI Inc. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. For a license to use on non-ModalAI hardware, please contact license@modalai.com --> <EscParameters> <IdParams> <param name="id" value="127"/> <!-- 0-7 .. 127 means use hardware ID pins to read ID--> <param name="dir" value="2"/> <!-- 0=fwd, 1=rev, 2=fwd id-based, 3=rev id-based --> </IdParams> <UartParams> <param name="protocol_version" value="2"/> <!-- reserved for future use --> <param name="input_mode" value="0"/> <!-- reserved for future use --> <param name="baud_rate" value="2000000"/> <!-- communication bit rate --> <param name="char_timeout_ns" value="0"/> <!-- not used --> <param name="cmd_timeout_ns" value="100000000"/> <!-- timeout for incoming commands before ESC will stop the motor --> </UartParams> <TuneParams> <param name="pwm_frequency" value="48000"/> <!-- switching freqency of PWM signal going to motors. 24Khz and 48Khz are only options for now --> <param name="vbat_nominal_mv" value="22200"/> <!-- used for sanity checking and limiting of voltage-dependent funcions --> <param name="num_cycles_per_rev" value="7"/> <!-- number of pole pairs in the motor. used for converting electrical frequency to mechanical rpm --> <param name="min_rpm" value="3020"/> <!-- WARNING: not tuned. minimum RPM that will be attempted, otherwise capped --> <param name="max_rpm" value="26311"/> <!-- WARNING: not tuned. maximum RPM that will be attempted, otherwise capped --> <param name="min_pwm" value="75"/> <!-- cap for minimum power to be ever applied. min is 75 --> <param name="max_pwm" value="9999"/> <!-- cap for maximum power to be ever applied. max is 999 --> <param name="pwm_vs_rpm_curve_a0" value="-92.6079829269"/> <!-- this is actually motor_voltage vs rpm curve.. using legacy naming --> <param name="pwm_vs_rpm_curve_a1" value="0.813657468926"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="pwm_vs_rpm_curve_a2" value="2.69099700436e-06"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="kp" value="0"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="ki" value="0"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="max_kpe" value="0"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="max_kie" value="0"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="max_rpm_delta" value="0"/> <!-- WARNING: RPM controller params are disabled since motor is not tuned --> <param name="spinup_type" value="1"/> <!-- 0: traditional, 1: sinusoidal --> <param name="spinup_power" value="60"/> <!-- power used to during spin-up procedure --> <param name="latch_power" value="60"/> <!-- power used during latching stage of spin-up (out of 999)--> <param name="spinup_power_ramp" value="8"/> <!-- it will take ( 4096 / (spinup_power_ramp*10000) ) seconds to ramp sinusoidal start-up power from 0 to spinup_power --> <param name="spinup_rpm_target" value="2000"/> <!-- Desired RPM at the end of the sinusoidal spin-up procedure --> <param name="spinup_time_ms" value="500"/> <!-- Duration of the sinusoidal spin-up procedure --> <param name="spinup_bemf_comp" value="1"/> <!-- 0: disable, 1:enable back-emf compensation in sinusoidal spin-up procedure --> <param name="motor_kv" value="2300"/> <!-- kV value of the motor. used in back-emf compensation during spin-up --> <param name="min_num_cross_for_closed_loop" value="10"/> <!-- exit latching mode of fixed power after this number of zero crossings --> <param name="protection_stall_check_rpm" value="1000"/> <!-- if motor spins below this RPM, stall check will trigger and stop / restart the motor --> <param name="brake_to_stop" value="0"/> <!-- apply brake when stopping motor (or not) --> <param name="stall_timeout_ns" value="20000000"/> <!-- after spin-up, if no zero crossing is not detected for this amount of time, motor is considered stalled --> <param name="require_reset_if_stalled" value="0"/> <!-- require sending an array of zero commands to reset before next spin-up, if motor stalled --> <param name="tone_freqs" value="[200, 215, 225, 250, 0,0,0,0, 0,0,0,0]"/> <!-- 200 is 2000Hz, max 255 --> <param name="tone_durations" value="[3, 0, 0, 0, 0,0,0,0, 0,0,0,0]"/> <!-- duration of each tone in units of 10 milli-seconds. Poor naming!!! --> <param name="tone_powers" value="[20, 0, 0, 0, 0,0,0,0, 0,0,0,0]"/> <!-- max is 255 --> <param name="dt_threshold_ns" value="150000"/> <!-- during start up, ignore inter-commutation times less than this val, probably noise --> <param name="max_dt_ns" value="2500000"/> <!-- min and max values for time between two commutations. these are used as caps --> <param name="min_dt_ns" value="10000"/> <param name="dt_bootstrap_ns" value="2000000"/> <!-- filter bootstrap value for commutation dt during start up --> <param name="spinup_stall_dt_ns" value="6000000"/> <!-- during spin-up, if no zero crossing is not detected for this amount of time, motor is considered stalled --> <param name="spinup_stall_check_ns" value="30000000"/> <!-- time after beginning of spinup to start checking for spinup stall --> <param name="alignment_time_ns" value="0"/> <!-- alignment time before spin-up --> <param name="timing_advance" value="0"/> <param name="sense_advance" value="0"/> <param name="demag_timing" value="0"/> <!-- unused --> <param name="led_config" value="0"/> <!-- 0: enable status LEDs in bootloader and firmware, 1: disable LEDs in boot and firmware: 2: disable LEDs only in firmware. need FW 39.25 or later --> </TuneParams> </EscParameters>@alex-kushleyev Alright I feel pretty dumb. But it is because the PID gains were zero in my config file...
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Hi @jbiscan21 ,
The main issue was that the
max_rpm_deltawas set to zero. Even with PI gains (and max errors) set to zero, you could have had it working with non-zeromax_rpm_delta. Let me explain.max_rpm_deltaterm is used to cap the target rpm relative to the current rpm. This is done to prevent very aggressive motor behavior, especially if motor is spinning very slowly because it is tangled in grass, etc, allowing unlimitedmax_rpm_deltacould cause motor to burn out or de-sync.The RPM controller has a feed-forward term and feedback terms.
- feedback terms are Proportional and Integral with corresponding gains and error terms (k * e).
- feed-forward term comes from the calibration : for desired RPM, the calibration tells the ESC what PWM (duty cycle) to apply
- there is also battery voltage compensation, so that even if voltage is changing, the feed-forward curve will still be accurate.
The rpm error is computed like so :
rpm_error = rpm_desired - rpm_current, which standard. But then it is capped with themax_rpm_delta, so if that is equal to zero, then rpm_error will be zero. One subtle detail is that the rpm_error is also used to look up the desired rpm feed_forward :rpm_for_feed_forward_term = rpm_current + rpm_error(roughly speaking), so having themax_rpm_deltaset to zero, caused the motor to be always stuck at minimum rpm.So you could still have zero P and I terms and the motor would use a feed forward term with voltage compensation and it would provide a nice and soft response (similar to traditional ESC). Adding P and I will make the response better than a traditional ESC.
In fact when using a new motor + prop, you should start off with P and I gains zero, just use a feed forward term to test at first and then you can increase the ESC's responsiveness by giving it more
max_rpm_deltaand also P and I terms. However, that is more advanced tuning should be done usingvoxl-esctools first in order ensure ESC response stability (we could discuss that in another thread).To answer your earlier questions:
- You could use pwm (power) control, but i have never used it with PX4. Perhaps @eric-katzfey can comment about that
- the ESC calibration for modalai ESCs calibrates the feed-forward term (as described above), and has to be done with a propeller. Yes, in flight, the air dynamics will change due to many factors such as air pressure, temperature, air speed, etc, etc, but the job of RPM controller is to keep a desired rpm. A higher level controller could potentially estimate the thrust vs rpm is changing due to air temperature or pressure difference from the calibrated response (outside of the scope of ESC's rpm controller).
Alex
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