No Servo Output on Skid Steer Rover

ArduRover Rover 4.2
1

I have been having this servo output problem for months now.
I have changed flight controllers, receivers and transmitters all to no avail.

I am getting the receiver showing movement in the calibration tab but no servo output for throttle and steering.
It is a skid steer rover now running a Matek H743 FC. Before this I have used Orange Cubes.
It has worked perfectly but now I am getting nothing.
Without the servo output I am unable to arm even.
My speed controller (Ampflow AF160) shows a constant red light denoting no receiver input. When working it should show a flashing red light every second.

I have attached log and parameter files to help.

Any help with this would be very much appreciated.

Cheers, Martin

9 01-01-1980 00-00-00.bin (376 KB)
01-11-2023.param (18.1 KB)

2

You have to arm to get servo output on anything labeled “throttle.”

You have MOT_PWM_TYPE set to brushed/bi-polar, but it looks like the speed controller you’re using is intended to accept normal RC pwm signals. That is likely a big part of the problem.

Your log shows valid RC input, but there are multiple messages regarding CRSF errors, so you may have some config errors on your RC setup. I don’t typically use CRSF, so I’m not much help there. I do use ELRS, which is a CRSF derivative, and it’s a pretty simple serial protocol. First step is to make sure you’ve followed the setup instructions to a tee.

I see no RC option set for arming, nor does it appear there is any attempt to arm.

Additionally, you seem to be using a DroneCAN GPS, but you have both SERIAL3 and 4 protocols set to GPS, which makes no sense. You should disable unused serial ports.

3

What about steering Yuri? Should that not show on the servo output page?

4

See my edit above.

Also, you have a skid steered setup, so there is no dedicated steering output. It’s all throttle, and you must arm to get output.

5

Thanks Yuri. I will work through your comments and report back.

6

Where would I find these errors?

7

I used MavExplorer to dump the messages from your log, but you’d see them live on the messages tab in Mission Planner.

18:00:08.515 ArduRover V4.2.3 (2172cfb3)
18:00:08.515 ChibiOS: 38022f4f
18:00:08.515 MatekH743 0050002B 32325101 36323737
18:00:08.515 Param space used: 525/3840
18:00:08.515 RC Protocol: CRSF
18:00:08.515 New mission
18:00:08.515 New rally
18:00:08.515 GPS 1: specified as UAVCAN1-125
18:00:08.712 CRSFv2: requesting RX device info
18:00:09.231 CRSFv2: requesting RX device info
18:00:09.731 CRSFv2: requesting RX device info
18:00:10.231 CRSFv2: requesting RX device info
18:00:10.455 EKF3 IMU0 initialised
18:00:10.456 EKF3 IMU1 initialised
18:00:10.731 CRSFv2: requesting RX device info
18:00:11.244 CRSFv2: requesting RX device info
18:00:11.744 CRSFv2: requesting RX device info
18:00:12.244 CRSFv2: requesting RX device info
18:00:12.255 EKF3 IMU0 tilt alignment complete
18:00:12.255 EKF3 IMU1 tilt alignment complete
18:00:12.335 EKF3 IMU0 MAG0 initial yaw alignment complete
18:00:12.336 EKF3 IMU1 MAG0 initial yaw alignment complete
18:00:12.744 CRSFv2: requesting RX device info
18:00:12.856 GCS:Mission Planner 1.3.80
18:00:12.856 GCS:Mission Planner 1.3.80
18:00:12.856 GCS:Mission Planner 1.3.80
18:00:13.264 CRSFv2: requesting RX device info
18:00:13.764 CRSFv2: requesting RX device info
18:00:13.936 ArduRover V4.2.3 (2172cfb3)
18:00:13.936 ChibiOS: 38022f4f
18:00:13.936 MatekH743 0050002B 32325101 36323737
18:00:13.936 RCOut: Brush:1-6 PWM:7-13
18:00:13.936 IMU0: fast sampling enabled 2.0kHz
18:00:13.936 IMU1: fast sampling enabled 2.0kHz
18:00:14.076 ArduRover V4.2.3 (2172cfb3)
18:00:14.076 ChibiOS: 38022f4f
18:00:14.076 MatekH743 0050002B 32325101 36323737
18:00:14.076 RCOut: Brush:1-6 PWM:7-13
18:00:14.076 IMU0: fast sampling enabled 2.0kHz
18:00:14.076 IMU1: fast sampling enabled 2.0kHz
18:00:14.216 ArduRover V4.2.3 (2172cfb3)
18:00:14.216 ChibiOS: 38022f4f
18:00:14.216 MatekH743 0050002B 32325101 36323737
18:00:14.216 RCOut: Brush:1-6 PWM:7-13
18:00:14.216 IMU0: fast sampling enabled 2.0kHz
18:00:14.216 IMU1: fast sampling enabled 2.0kHz
18:00:14.264 CRSFv2: requesting RX device info
18:00:14.764 CRSFv2: requesting RX device info
18:00:15.032 CAN[125] GPS 1: u-blox saving config
18:00:15.264 CRSFv2: requesting RX device info
18:00:15.764 CRSFv2: requesting RX device info
18:00:16.264 CRSFv2: requesting RX device info
18:00:16.764 CRSFv2: requesting RX device info
18:00:17.048 CAN[125] u-blox 1 HW: 00080000 SW: EXT CORE 3.05 (ff96ba)
18:00:17.291 CRSFv2: requesting RX device info
18:00:17.791 CRSFv2: requesting RX device info
18:00:18.292 CRSFv2: requesting RX device info
18:00:18.798 CRSFv2: requesting RX device info
18:00:19.298 CRSFv2: requesting RX device info
18:00:19.798 CRSFv2: requesting RX device info
18:00:20.311 CRSFv2: requesting RX device info
18:00:20.818 CRSFv2: requesting RX device info
18:00:21.318 CRSFv2: requesting RX device info
18:00:21.818 CRSFv2: requesting RX device info
18:00:22.318 CRSFv2: requesting RX device info
18:00:22.818 CRSFv2: requesting RX device info
18:00:23.318 CRSFv2: requesting RX device info
18:00:23.818 CRSFv2: requesting RX device info
18:00:24.318 CRSFv2: requesting RX device info
18:00:24.818 CRSFv2: requesting RX device info
18:00:25.331 CRSFv2: requesting RX device info
18:00:25.832 CRSFv2: requesting RX device info
18:00:26.338 CRSFv2: requesting RX device info
18:00:26.838 CRSFv2: RX device ping failed
8

Thanks Yuri. Your help is very much appreciated. I’ll check out the MavExplorer. I can’t believe all that information is available!
I’ll be checking out the messages tab from now on.

9

@Yuri_Rage Hi,
I have downloaded the MavExplorer and managed to drag a log file in but have no idea how to dump the messages.
I can view the graphs OK.
Can you tell me the syntax to display the messages from the command prompt?
There seems to be very little information on how to use the terminal.
I have included a screen shot of where I have got to.
Cheers,
Martin

Screenshot 2023-11-02 110649
Screenshot 2023-11-02 1106491109Ă—624 16.9 KB

10

https://ardupilot.org/dev/docs/using-mavexplorer-for-log-analysis.html

11

Thank you @Yuri_Rage .
I did see that previously.
I have typed “messages” at the command prompt but only get the ones you came up with, yet it says there are 9288 of them.
Is there a way of viewing the others?

12

There are 9k MavLink messages. The command you are typing is to display the subset that are GCS text messages.

You should focus more time on getting a running vehicle rather than continuing to dissect a log with so little useful data.

13

Thanks Yuri. I agree. I just wanted to know how to look at the messages moving forward.
The MavExplorer will be a very useful tool.

14

@Yuri_Rage
Thanks for all your help so far. I have spent another full day on the Rover working on your thoughts.
Pleased to report the following:

You have to arm to get servo output on anything labeled “throttle.”

Understood

You have MOT_PWM_TYPE set to brushed/bi-polar, but it looks like the speed controller you’re using is intended to accept normal RC pwm signals. That is likely a big part of the problem.

Have changed to Normal which gave me the outputs I need after arming. It was working on Bipolar before but have followed your suggestion.

Your log shows valid RC input, but there are multiple messages regarding CRSF errors, so you may have some config errors on your RC setup. I don’t typically use CRSF, so I’m not much help there. I do use ELRS, which is a CRSF derivative, and it’s a pretty simple serial protocol. First step is to make sure you’ve followed the setup instructions to a tee.

I have kept with CRSF and is now working without any error messages. At least I can now see the correct LED status on the speed controller. However, The speed controller output is not correct. One side is slower than the other. I’m not sure the motor test is correct though. I will do a video to show what is happening.

I see no RC option set for arming, nor does it appear there is any attempt to arm.

I did not attempt to arm in the logs I sent… Arming is done by right roll stick to the left for 2 seconds. Working.

Additionally, you seem to be using a DroneCAN GPS, but you have both SERIAL3 and 4 protocols set to GPS, which makes no sense. You should disable unused serial ports.

These were the default values. I have disabled them as you suggested.

I have ordered another speed controller to see if it that is the problem. Not sure it is. At least I will have all the parts to build another one if I can’t sort this one out!

Thanks Yuri for helping me get back on track! Much appreciated.

Hopefully get that video to you by the end of the weekend.

Cheers,

Martin

15

@Yuri_Rage
By the way, the message tab has been very useful today. I spotted a problem when I set up a switch to arm. I used the same one as the lights and it showed up that I was using the switch for two functions!

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16

Speed controller output wrong, one side slower than the other…:

What if you reverse? Is it then the other way around? The one working slower than the other becomes faster than the other if driving in reverse?

17

I’ll check that. Thank you.

18

Do that. I mainly focus on skid steering boats, with mirrored layout of the propeller blades on each side - ie the motors must run in opposite direction to push forward. And some ESCs I have used (that are programmable) have a lowered reverse throttle force by default. Like hobbywing quicrun 1080 (brushed) and 16BL30 (brushless). I make sure to raise the “max reverse force” to 100 % with these as the default is less.

19

Discussion continues here. Evidence points to improper motor controller mode.

1 Like