[3.5.0-rc.1] Constant torque mode not working
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Hi all, I'm currently messing around with the 1HCL expansion board and it's closed loop feature.
M569.4 should put the driver into constant torque mode, but I can't observe any change in behaviour.
I configure the driver like this:
M569.1 P21.0 T3 R10 S200 ;closed loop config for drive 21.0, magnetic shaft encoder M569 P21.0 S1 D4 ; physical drive 21.0 goes forward and closed loop is enabledAnd I put it into constant torque mode like this:
(Edit: I also tried much larger values)M569.4 P21.0 T0.001In my understanding, the stepper should start spinning now (as there's no significant load).
But after being put into constant torque mode, the stepper doesn't move, and still responds to G1 commands.
What am I doing wrong?
M122 here: https://pastebin.com/1nUX0N57
config here: https://pastebin.com/LihR1YwU
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- Use M122 B21 to check that the 1HCL board is also running the RC1 firmware and its status is OK.
- Use the Q parameter of the M569.1 command to specify the torque constant of the motor.
Duet WiFi hardware designer and firmware engineer
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@dc42
Firmware was okay, the Q-parameter did the trick. Thanks a lot! -
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undefined Phaedrux has marked this topic as solved
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@nikscha I'm tinkering with a constant torque controller myself and want to drive it through Duet RRF. I want to use the step/dir +enable pins.
Do you know if the direction pin changes, when you apply negative T-values?
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Hi @o_lampe
I'm not quite sure whether I understand your question
I'm using the 1HCL toolboard which offers support for closed loop controll and through that also constant torque mode. The toolboard has an onboard microcontroller which (I assume) does all the closed loop/constant torque stuff. I also assume that the micro is talking to the driver via SPI, so there's no step/dir interface in play.What pin exactly do you want me to observe when I apply negative T-values?
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@o_lampe said in [3.5.0-rc.1] Constant torque mode not working:
Do you know if the direction pin changes, when you apply negative T-values?
The direction of the applied torque does change. The direction pin of the stepper driver chip is not used in closed loop modes.
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@dc42 one more follow-up question:
After resetting the printer and turning on constant torque mode for my drive nothing happens. I first need to execute a normal move or I need to enable the driver via M17 first.
Is this intended behaviour? There's no error message either (when i try to turn on constant torque mode while in open loop mode, I get an error for example).
I think it would be better if the M569.4 command enables the driver automatically. -
@nikscha currently commanding torque mode does not enable the driver, hence the need to command M17 or a normal move first. I will raise a Github issue about this.
