Scara Setup
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David
it was interesting to see your Scara project from robotdiggs. I guess I was thinking along the same line and purchased this Scara from robotdiggs.
I have it all wired up and I purchase a Duet wifi which should arrive tomorrow.https://www.robotdigg.com/product/1193/Closed-loop-Stepper-Motor-SCARA-Robot-Arm
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David
it was interesting to see your Scara project from robotdiggs. I guess I was thinking along the same line and purchased this Scara from robotdiggs.
I have it all wired up and I purchase a Duet wifi which should arrive tomorrow.https://www.robotdigg.com/product/1193/Closed-loop-Stepper-Motor-SCARA-Robot-Arm
It will be interesting to compare our experiences. You may find that you can get rid of the distal arm backlash just by replacing the distal arm belts with ones from the UK supplier that I used for the proximal arm belt, instead of replacing the belts and pulleys by GT2 ones. I suggest you still replace the 20 tooth pulley by a 16 tooth one, to get a higher steps per degree.
Another upgrade I am considering is to replace the proximal and distal motors by 0.9deg ones.
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Thanks for your comments about backlash, but this model has virtually zero backlash. I'm using hybrid closed loop stepper motors which should be quite accurate for the scara
Have a look at the photo and you can see some initial setup parameters.
Do you have the config file for your current robotDiggs Scara, this might be helpful.
I'm using external driver signals off of the header, how do you reassign these to x y and z.
thanks Dannyhttps://www.dropbox.com/s/27ekssq1lk9ntzd/scara%20robotdiggs.jpg?dl=0
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Extern drivers must be connected to the expansion connector (I hope that is what you mean by "the header"). Use M584 to remap the XYZ axes to them, see https://duet3d.com/wiki/G-code#M584:_Set_drive_mapping. Depending on the drivers and how you have connected them, you may need to use the R1 parameter in the M569 commands to invert the Enable signal.
Here is my config.g file:
; Configuration file for Duet Ethernet in SCARA printer (firmware version 1.19)
; General preferences
M111 S0 ; Debug off
M550 PRobotdigg SCARA ; Machine name
M551 Preprap ; Machine password
M552 S1 ; Enable networking
M555 P2 ; Set USB output to look like Marlin
M575 P1 B57600 S1 ; Set aux port baud rate and require checksum, for PanelDue; Drives
M569 P0 S0 ; Drive 0 goes backwards X
M569 P1 S1 ; Drive 1 goes forwards Y
M569 P2 S0 ; Drive 2 goes backwards Z
M569 P3 S0 ; Drive 3 goes backwards E; Movement
M669 K4 P160 D159.5 A-130:22 B-27:157.5 C0:0:0 X65 Y-175 S100 ; set SCARA mode and parameters
M574 X2 Y2 Z1 S1 ; Define active high homing switches
M92 X71.1111 Y100 ; Steps/degree for proximal and distal joints
M92 Z1600 E106 ; Steps/mm for Z and EM208 S1 X0 Y-120 Z-1 ; Axis minima
M208 X200 Y330 Z150 ; Axis maximaM350 X16 Y16 Z16 U16 E16:16 I1 ; x16 microstepping with interpolation
M566 X500 Y500 Z100 E500 ; XYZE jerk (mm/min)
M203 X4500 Y4500 Z600 E3600 ; Maximum speeds (mm/min)
M201 X300 Y300 Z50 E1000 ; Accelerations (mm/s^2)
M906 X1000 Y1000 Z1000 E1300 I30 ; Motor currents (mA) and motor idle percent; Heaters
M143 H1 S260 ; Maximum heater temperature
M140 H-1 ; No bed heater
M305 P1 T100000 B4138 C0 R4700 ; Thermistor parameters for heater 1
M307 H1 A577.0 C199.0 D9.8 S1.00 B0; Tools
M563 P0 D0 H1
G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets
G10 P0 R00 S00 ; Set initial tool 0 active and standby temperatures to 0C; Fans
M106 P1 S0 I0 F200 H1 T45 ; Fan 1 frequency, thermostatic control; Z probe
M558 P1 X0 Y0 Z0 F600 T10000 R0.4
G31 P500 Z1.75
M557 X25:175 Y-100:325 S25 ; grid for G29 probing
M671 X-45:-300:-45 Y0:175:350 P1.0 ; adjusting screw positions, M6 screw = 1mm pitch; Power fail not configured
; Pressure advance
M572 D0 S0.5; Misc
M83
T0 -
Yes I'm using the expansion port , I'm connecting on 2 5 6 and 7. I've connect to the motor on E2. I think I've configured M584 and M569 correct but I don't have any movement. I've changed the engage signal also.
; SCARA MINI
M111 S0 ; Debug off
M550 SCARA MINI ; Machine name and Netbios name (can be anything you like)
M551 Preprap ; Machine password (used for FTP)
;*** If you have more than one Duet on your network, they must all have different MAC addresses, so change the last digits
M540 P0xBE:0xEF:0xDE:0xAD:0xFE:0xED ; MAC Address;*** Networking
M552 S1 ; Turn network on;*** Ethernet networking: Adjust the IP address and gateway in the following 2 lines to suit your network
M552 P192.168.1.14 ; (0 = DHCP)
M554 P192.168.1.255 ; Gateway
M553 P255.255.255.0 ; NetmaskM555 P2 ; Set output to look like Marlin
G21 ; Work in millimetres
G90 ; Send absolute coordinates…
M83 ; ...but relative extruder moves; Disable Fan 1 thermostatic mode
M106 P1 H-1
M584 X2 Y3 Z4 E5 ;Set drive mapping
; Axis and motor configuration
;M569 P0 S1 ; Drive 0 goes forwards
;M569 P1 S1 ; Drive 1 goes forwards
M569 P2 S0 R1 ; Drive 2 goes forwards
;M569 P3 S1 ; Drive 3 goes forwards
;M569 P4 S1 ; Drive 4 goes forwards
M669 K4 P200 D200 A-179:170 B-120:120 C0:0:0 ; set SCARA mode and parameters
M574 X2 Y2 Z2 S1 ; set endstop configuration (all endstops at high end, active high)
;*** The homed height is deliberately set too high in the following - you will adjust it during calibrationM666 X0 Y0 Z0
M208 S1 X179 Y-121 Z-1 ; Axis minima
M208 X179 Y121 Z100 ; Axis maxima ; put your endstop adjustments here, or let auto calibration find them
M350 X1 Y1 Z1 E1 I1 ; Set 16x microstepping with interpolation
M92 X25.9820 Y17.777 ; Steps/degree for proximal and distal joints
M92 Z1600 E106 ; Steps/mm for Z and E
M906 X1000 Y1000 Z1000 E800 I60 ; Set motor currents (mA) and increase idle current to 60%
M201 X1000 Y1000 Z1000 E1000 ; Accelerations (mm/s^2)
M203 X2000 Y2000 Z2000 E3600 ; Maximum speeds (mm/min)
M566 X1200 Y1200 Z1200 E1200 ; Maximum instant speed changes mm/minute; Thermistors
;M305 P0 T100000 B3950 R4700 H30 L0 ; Put your own H and/or L values here to set the bed thermistor ADC correction
;M305 P1 T100000 B3974 R4700 H30 L0 ; Put your own H and/or L values here to set first nozzle thermistor ADC correction
;M305 P2 T100000 B3974 R4700 H30 L0 ; Put your own H and/or L values here to set 2nd nozzle thermistor ADC correction; Tool definitions
M563 P0 D0
;G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets
;G10 P0 R00 S00 ; Set initial tool 0 active and standby temperatures to 0CM92 E663:663 ; Set extruder steps per mm
;*** If you are using axis compensation, put the figures in the following command
;M556 S78 X0 Y0 Z0 ; Axis compensation hereM208 S1 Z-0.2 ; set minimum Z
;T0 ; select first hot end
; Pressure advance
;M572 D0 S0.5; Misc
M83 -
Please clarify what you have connected where. Your M584 command says you are using stepper drivers on the Duet for X, Y and Z (but not the usual outputs) and you have one external stepper driver for the extruder.
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David I only have one hybrid stepper hooked up to the expansion connector for testing on E2. I'm trying to get this to work before I wire up the rest.
E2 X hybrid stepper
E3 Y hybrid stepper
E4 Z hybrid stepper
E5 Extruder hybrid stepper -
hybrid stepper hook up pic.
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Your M584 command is this:
M584 X2 Y3 Z4 E5 ;Set drive mapping
So you currently have the extruder motor assigned to driver 5 (labelled E2 on the expansion board). Is that what you intended?
To get that extruder driver working, there are a few things you will need to do:
1. Select a tool that uses extruder drive 0.
2. Either heat up the associated heater, or send M302 P1 to enable cold extrusion.
3. Depending on your external driver, you may need to use a M569 command to extend the set pulse timing and/or invert the enable signal, like this:M569 P5 R1 T2
R1 will invert the enable signal to make it active high (the default is R0 which means active low), and T2 extends the step pulse width and minimum interval to 2us.
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David here is what I'm trying to do, there is no Tool because this will be a clay printer so there's no hot end just one extruder
Please check my external driver configuration. I still have not been able to get E2 motor to turn ,although if I change the engage parameter I do see this on the motor. Also I've tried T2 and T4 and have tried engage signal in both positions .
Now that I've spent a fair bit of time on the interface I can really say it is fantastic. I'm used to smoothieware and this is so much easier and well laid out. Good job
E2 X hybrid stepper
E3 Y hybrid stepper
E4 Z hybrid stepper
E5 Extruder hybrid stepperM584 X5 Y6 Z7 E8 ;Set drive mapping
; Axis and motor configuration
M569 P5 S0 R0 T4 ; Drive 0 goes forwards X
M569 P6 S0 R0 ; Drive 1 goes forwards Y
M569 P7 S0 R0 ; Drive 2 goes forwards Z
M569 P8 S0 R0 ; Drive 3 goes forwards E -
Thanks for the compliment!
You have to define and select a tool to use an extruder. You can define a tool with no heater, like this:
M563 D0M563 P0 D0 -
Okay I understand about selecting extruder as tool, and I inserted M563 D0
However I am only testing a single motor on E2.
So far I am unable to get this motor to function, although it is responding to the enable signal. -
I'm sorry, that should have been:
M563 P0 D0
i.e. define tool 0 as using extruder drive 0 (which will correspond to the first E driver number in your M584 command). Then you need to select that tool by sending T0. After that, you should be able to extrude.
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I guess I'm a little confused because I'm trying to assign E2 as X. This is where I have my test motor hooked ,it doesn't pertain to the extruder.
I have the end switchs turned off and no hotend so is there something else holding back the signals on E2?
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To test the X motor by itself, send G91 first, then send G1 S2 X commands. For example, G1 S2 X10 should move the proximal (X) joint anticlockwise by 10 degrees, and G1 S2 X-10 should move it clockwise by 10 degrees. The first time you send one of these G1 S2 X commands, the motor should be energised, if you have the Enable polarity right.
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Okay got it working thanks. Will be setting up and calibrating
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Is there any easy way to use these proximity switches?
On my smoothieboard it's easy to switch from 3.3v to 5 volts for the end stop switches. These will operate on 5v even though they State 6 volts minimum -
Is there any easy way to use these proximity switches. On my smoothieboard it's easy to switch from 3.3v to 5 volts for the end stop switches. These will operate on 5v even though they State 6 volts minimum
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The endstop connectors are 3.3V. You can get 5V power from the expansion connector or the PanelDue connector to power 5V endstops. If they are NPN output sensors, you can connect the output directly to the endstop input pin. With 12V or 24V sensors I recommend connecting a diode in between to protect the endstop input in the event of loss of the ground wire, but that isn't really necessary with 5V endstops.
Personally, I would just use microswitches. They may even be more reproducible than inductive sensors, which can be a little temperature-sensitive.
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David
I have proximal and distal homing working, but I don't want to use a probe for Z homing.
I'd like the Z to go all the way to the top and hit limit switch for homing.
I have set Z height 200mm; File homez.g
G91 ; relative movement
G1 S2 Z4 F200 ; raise head 4mm to ensure it is above the Z probe trigger height
G90 ; back to absolute mode
G1 X100 Y100 F2000 ; put head over the centre of the bed, or wherever you want to probe
G30 ; lower head, stop when probe triggered and set Z to trigger height
