Plan to switch from normal steppers to 1HCL+ magnetic encoders

martin7404

@dc42 Does that mean 0.9 steppers will have problems running in closed loop ?

dc42

@martin7404 they should run OK, however the speed won't be as high as you can get using 1.8deg motors and the tuning will be more critical. With a closed loop motor it's the encoder that determines the resolution, not the motor.

martin7404

@dc42 Thank you . I get this but these are on the machine. Any guidelines about PID tuning. I managed to make it today following the wiki guide and my graphs are more "noisy" is this to be expected. It is a big machine with 0.6 and 0.8revo nozzles. But I limit the acceleration a lot , hopin to improve this by going closed loop

martin7404

@dc42 Something to ask
When you do manual tuning with the plugin after it is finished.
How to save the tuned parameters?
Do I need to enter them in config.g in the 569.1 command?

dc42

@martin7404 yes you need to put the new parameters in the M569.1 command in config.g.

martin7404

@dc42 does this manual tooling look OK?
This is what I cma up after following the tuning guide

martin7404

this is the second motor

martin7404

the final config.g

; Configuration file for Duet 3 (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v3.2.3 on Thu May 27 2021 13:17:12 GMT+0300 (Eastern European Summer Time)

; General preferences 
G90                                                    ; send absolute coordinates...
M83                                                    ; ...but relative extruder moves
M550 P"CoreXY500"                                     ; set printer name
M669 K1                                                ; select CoreXY mode

; Network
M552 P192.168.1.27 S1                                       ; enable network and acquire dynamic address via DHCP
M586 P0 S1                                             ; enable HTTP
M586 P1 S0                                             ; disable FTP
M586 P2 S0                                             ; disable Telnet
G4 S2   ;wait for expansion boards to start


; Drives
M569.1 P50.0 T3 E4:8 S400 R40 I1500 D0.05 V400 A200000 H10 ; Configure the Duet 3 Expansion 1HCL board at CAN address 50 with a Duet 3 magnetic encoder, warn if 1 fullstep threshold exceeded, error if 2 full steps threshold exceeded.
M569 P50.0 D4 S1 ;
;M569 P0.0 S1                                           ; physical drive 0.0 goes forwards
;M569 P0.1 S0                                    ; physical drive 0.1 goes forwards
M569.1 P51.0 T3 E4:8 S400 R40 I1500 D0.05 V400 A200000 H10 ; Configure the Duet 3 Expansion 1HCL board at CAN address 50 with a Duet 3 magnetic encoder, warn if 1 fullstep threshold exceeded, error if 2 full steps threshold exceeded.
M569 P51.0 D4 S0
M569 P0.3 S0
M569 P0.4 S1  
M569 P0.5 S1                                           ; physical drive 0.2 goes forwards
M569 P121.0 S1                                         ; physical drive 121.0 goes forwards
M584 X50.0 Y51.0 Z0.3:0.4:0.5 E121.0                             ; set drive mapping
M350 X16 Y16 Z16 E16 I1                                ; configure microstepping with interpolation
M92 X160.00 Y160.00 Z8280.00 E395.70                      ; set steps per mm
;M350 X32 Y32 Z16 E16 I1
M566 X300.00 Y300.00 Z50.00 E120.00                    ; set maximum instantaneous speed changes (mm/min)
M203 X12000.00 Y12000.00 Z150.00 E1200.00                ; set maximum speeds (mm/min)
M201 X1000.00 Y1000.00 Z20.00 E500.00                    ; set accelerations (mm/s^2)
M906 Z1000 E800 I30                           ; set motor currents (mA) and motor idle factor in per cent
M906 X1700 Y1700 I30 
M84 S30                                                ; Set idle timeout

; Axis Limits
M208 X-26 Y0 Z0 S1                                       ; set axis minima
M208 X500 Y330 Z365 S0                                 ; set axis maxima

; Endstops
M574 X1 S4                                             ; configure sensorless endstop for low end on X
M574 Y1 S4                                             ; configure sensorless endstop for low end on Y
M574 Z1 S2                                             ; configure Z-probe endstop for low end on Z
;M574 E1 S1
;Filament sensor BTT E1
M591 D0 P2 C"io8.in" S1 ;configure BTT smart filament sensor
; Z-Probe
M671 X-31.39:250:531.36 Y-18:433.3:-18 S10       ; Locations left, center, right   
M558 P8 C"121.io2.in"  H3 F1000 T6000 A20 S0.005 ; PINDA set Z probe type to switch and the dive height + speeds
;M308 S2 P"121.temp1" A"PINDA" Y"thermistor" T100000 B3950
;M950 H2 C"out1" T2                                 ; create nozzle heater output on 121.out0 and map it to sensor 1
;M307 H2 B0 S1.00                                       ; disable bang-bang mode for heater  and set PWM limit
;M141 H2
;M143 H2 S90                                           ; set temperature limit for heater 1 to 280C
G31 P500 X30 Y0 Z1.48                            ; set Z probe trigger value, offset and trigger height
M557 X20:450 Y5:320 P5                             ; define mesh grid

; Heaters
M308 S0 P"temp0" Y"thermistor" T100000 B4138           ; configure sensor 0 as thermistor on pin temp0
M950 H0 C"out0" T0 Q10                                     ; create bed heater output on out0 and map it to sensor 0
M307 H0 B0 S1                                      ; disable bang-bang mode for the bed heater and set PWM limit
M140 H0                                                ; map heated bed to heater 0
M143 H0 S130                                          ; set temperature limit for heater 0 to 120C
M308 S1 P"121.temp0" Y"thermistor" T100000 B4725 C7.060000e-8       ; configure sensor 1 as thermistor on pin 121.temp0
M950 H1 C"121.out0" T1                                 ; create nozzle heater output on 121.out0 and map it to sensor 1
M307 H1 B0 S1.00                                       ; disable bang-bang mode for heater  and set PWM limit
M143 H1 S290     ; set temperature limit for heater 1 to 280C

M308 S2 A"Chamber" P"temp2" Y"thermistor" T100000 B4725 C7.06e-8
M950 H2 C"out2" T2                                 ; create nozzle heater output on 121.out0 and map it to sensor 1
M307 H2 R0.001 A11 C99999 D4000 B1   ; disable bang-bang mode for heater  and set PWM limit
M141 H2
M143 H2 S70

; Fans
M950 F0 C"121.out1"                               ; create fan 0 on pin 121.out1 and set its frequency
M106 P0 S0 B0.5 H-1                                         ; set fan 0 value. Thermostatic control is turned off
M950 F1 C"121.out2" Q500                               ; create fan 1 on pin 121.out2 and set its frequency
M106 P1 S1 H1 T45                                      ; set fan 1 value. Thermostatic control is turned on

; Tools
M563 P0 D0 H1 F0                                       ; define tool 0
G10 P0 X0 Y0 Z-0.15                                        ; set tool 0 axis offsets
G10 P0 R0 S0                                           ; set initial tool 0 active and standby temperatures to 0C

; Custom settings are not defined
M955 P121.0 I05 ;Accelerometer on Toolboard
; Miscellaneous
M575 P1 S1 B57600                                      ; enable support for PanelDue
M572 D0 S0.045 ; PA for ABS GD filament 0.4 nozzle
M501                                                   ; load saved parameters from non-volatile memory
M911 S22.5 R23.5 P"M913 X0 Y0 G91 M83 G1 Z3 E-5 F1000" ; set voltage thresholds and actions to run on power loss

``'

martin7404

@dc42 Everything works but with 0.8 nozzle, I have to run pretty slow and there is too much vibration in closed-loop mode, so I switched to assisted open loop
I get a lot of these

Do you mean R value in M569.1 ?

martin7404

@martin7404 From time to time, it pauses due to these errors, and when I resume,e there is a slight layer shift
For now, for the big nozzle, I am switching to open loop with high current on the motors.
And will use a closed loop when printing with a smaller nozzle
May be in the future I will switch the motors to 1.8 and will test tuning them again

dc42

@martin7404 the warning .messages mean that the M569.1 E value has been exceeded.

If the motors are noisy in closed loop mode, reduce the D term. If they tend to oscillate, reduce the R term or increase the D term.

martin7404

@dc42 In a closed loop, D is 0, and still, for a 0.8 nozzle, I tend to run at 30-40 mm/s, and at that speed, it is very noisy. The assisted open loop leads to shifts. Unfortunately, these parts are in production, and I just went back to open loop with reduced Acceleration and higher motor current. We will deal with the setup after this job is finished

martin7404

@martin7404 After some time, printing with the machine, system started to mismatch the 3 Z motors during print
I thought one of my motors is going bad.
Still, after some testing, I found out that if I switch the A and B motors to the main board, completely eliminating the closed-loop boards, it works as before. So, for now, I am removing all HCL closed-loop electronics and writing off the time spent.
I will probably use the hardware in a future project. The machine is needed for production printing, and we remain the "Slow ABS printer"

dc42

@martin7404 did you try reducing the M569.1 R term? If so, what was the result?

martin7404

@dc42, not good, the sensorless homing is not working onthe lower R setting. I believe the main problem is that I use 0.9 steppers, which do not allow me to properly tune the motors in closed loop

dc42

@martin7404 the M569.1 parameters only affect closed loop and assisted open loop modes, so they should have no effect when performing sensorless homing in open loop mode.

Getting 0.9deg motors working well in closed loop mode can be challenging. In particular, the encoder calibration is more critical and the maximum speed will be lower.