ESC suudenly stopped working after updating px4 parameters

Tamas Pal 0

ESC suddenly stopped working after updating px4 pid parameters. I am able to detect esc using ftdi cable; I have also rechecked the voxl2 - ESC UART cable. There is no hardware issue. How to fix it ?

Alex Kushleyev

Can you please double check that uart_esc module is enabled and correct baud rate is used (250K default). Do you still have the parameters that you used when ESC was working? Maybe try those.

Tamas Pal 0

@Alex-Kushleyev The esc module is enabled but

qshell mixer load /dev/uart_esc quad_x.main.mix

The uart_esc file is missing even after conecting the esc with voxl2. There is no hardware damage. I have checked all the ports many times with multimeter inclding the voltage of RX-TX with respect to ground. All the things are good. I have tested it another voxl2, even tried it with differnt cable. The issue is still there. How to fix the issue?

Alex Kushleyev

You should try to use the following commands:

qshell modalai_esc status

also check

qshell param show UART_ESC*

Anubhav

Hi @Alex-Kushleyev,

I have tried running the above command:

voxl2:~$ px4-qshell modalai_esc status
INFO  [qshell] Send cmd: 'modalai_esc status'
INFO  [qshell] qshell return value timestamp: 798550454, local time: 798557832

voxl2:/$ px4-qshell param show UART_ESC*
INFO  [qshell] Send cmd: 'param show UART_ESC*'
INFO  [qshell] qshell return value timestamp: 785736853, local time: 785740154

I think voxl2 is not detecting ESC, how can I resolve this?

modaltb

Hi @Tamas-Pal-0 ,

Sorry some of the stdout responses don't make it to the shell when evoked with px4-, can you try this section of the developer guide to run PX4 interactively through the shell?

https://docs.modalai.com/voxl-px4-developer-guide/#how-to-access-the-px4-shell-pxh

After that, and you run voxl-px4 manually, you will get a pxh shell, and then the qshell modalai_esc status command should spit out info.

Also, for the param check, no qshell needed, you can use param show UART_ESC* from the pxh shell.

Alex Kushleyev

@modaltb , just wanted to double check.. inside pxh shell, the command should be just modalai_esc status (without qshell), right?

Anubhav

@Alex-Kushleyev @modaltb

Below is the output of the command qshell modalai_esc status while the ESC was connected and powered on:

INFO  [qshell] Send cmd: 'modalai_esc status'
INFO  [muorb] SLPI: Marking DeviceNode(qshell_req) as advertised in process_remote_topic
INFO  [muorb] SLPI: qshell gotten: modalai_esc status
INFO  [muorb] SLPI: Max update rate: 0 Hz
INFO  [muorb] SLPI: Outputs on: no
INFO  [muorb] SLPI: UART port: 2
INFO  [muorb] SLPI: UART open: yes
INFO  [muorb] SLPI: 
INFO  [muorb] SLPI: Params: UART_ESC_CONFIG: 1
INFO  [muorb] SLPI: Params: UART_ESC_BAUD: 250000
INFO  [muorb] SLPI: Params: UART_ESC_MOTOR1: 3
INFO  [muorb] SLPI: Params: UART_ESC_MOTOR2: 2
INFO  [muorb] SLPI: Params: UART_ESC_MOTOR3: 4
INFO  [muorb] SLPI: Params: UART_ESC_MOTOR4: 1
INFO  [muorb] SLPI: Params: UART_ESC_RPM_MIN: 1000
INFO  [muorb] SLPI: Params: UART_ESC_RPM_MAX: 10500
INFO  [muorb] SLPI: 
INFO  [muorb] SLPI: -- ID: 0
INFO  [muorb] SLPI:    State:           0
INFO  [muorb] SLPI:    Requested:       0 RPM
INFO  [muorb] SLPI:    Measured:        0 RPM
INFO  [muorb] SLPI:    Command Counter: 0
INFO  [muorb] SLPI:    Voltage:         0.000000 VDC
INFO  [muorb] SLPI: 
INFO  [muorb] SLPI: -- ID: 1
INFO  [muorb] SLPI:    State:           0
INFO  [muorb] SLPI:    Requested:       0 RPM
INFO  [muorb] SLPI:    Measured:        0 RPM
INFO  [muorb] SLPI:    Command Counter: 0
INFO  [muorb] SLPI:    Voltage:         0.000000 VDC
INFO  [muorb] SLPI: 
INFO  [muorb] SLPI: -- ID: 2
INFO  [muorb] SLPI:    State:           0
INFO  [muorb] SLPI:    Requested:       0 RPM
INFO  [muorb] SLPI:    Measured:        0 RPM
INFO  [muorb] SLPI:    Command Counter: 0
INFO  [muorb] SLPI:    Voltage:         0.000000 VDC
INFO  [muorb] SLPI: 
INFO  [muorb] SLPI: -- ID: 3
INFO  [muorb] SLPI:    State:           0
INFO  [muorb] SLPI:    Requested:       0 RPM
INFO  [muorb] SLPI:    Measured:        0 RPM
INFO  [muorb] SLPI:    Command Counter: 0
INFO  [muorb] SLPI:    Voltage:         0.000000 VDC
INFO  [muorb] SLPI: 
INFO  [muorb] SLPI: modalai_esc: cycle: 85537 events, 9228157us elapsed, 107.88us avg, min 4us max 440us 9.18
INFO  [muorb] SLPI: modalai_esc: output update interval: 85534 events, 2056.72us avg, min 1249us max 3206224u
INFO  [muorb] SLPI: control latency: 85533 events, 49030648us elapsed, 573.24us avg, min 372us max 925us 62.2
INFO  [muorb] SLPI: Switched to rate_ctrl work queue: 1
INFO  [muorb] SLPI: Mixer loaded: yes
INFO  [muorb] SLPI: Driver instance: 0
INFO  [muorb] SLPI: Channel Configuration:
INFO  [muorb] SLPI: Channel 0: value: 0, failsafe: 0, disarmed: 0, min: 1000, max: 10500
INFO  [muorb] SLPI: Channel 1: value: 0, failsafe: 0, disarmed: 0, min: 1000, max: 10500
INFO  [muorb] SLPI: Channel 2: value: 0, failsafe: 0, disarmed: 0, min: 1000, max: 10500
INFO  [muorb] SLPI: Channel 3: value: 0, failsafe: 0, disarmed: 0, min: 1000, max: 10500
INFO  [muorb] SLPI: Ok executing command: modalai_esc status
INFO  [muorb] SLPI: Sending qshell retval with timestamp 949539937, current timestamp 949539938
INFO  [qshell] qshell return value timestamp: 949539937, local time: 949553192

Alex Kushleyev

It seems no data has been received by modal_esc module, but it also seems that the ESCs have not been armed yet. Let's try to query the individual ESC version information:

modalai_esc -i 0 version

and

modalai_esc -i 0 version-ext

(you can replace -i 0 with ESC ID 0..3)

These commands will explicitly send a request to each ESC and get information about its version and should print. version-ext is the extended version information, but basic version command should be sufficient for checking communication.