Duet3DWifi Firmware for 6 Axis Robotic Arm



  • Hi All,

    I have a DuetWifi and Duet2 Board in hopes to control a 3D Printed 6 axis robotic arm. I am using Nema 17 Steppers and 1x Nema 23 for the shoulder joint.

    I have had a go at modifying the RepRap firmware but i am getting insufficient axis homing messages and due to having 25:1 and 50:1 gear ratios at the joints, i'v had to make the bed size very very large for the motors to provide adequate rotation. This seems like a quick workaround to get the motors turning, but i want something that works better than this solution.

    1) Can you run other firmware the DuetWifi and if so, which?

    2) Can the gear ratios somehow be put into the firmware?



  • @mattling9 said in Duet3DWifi Firmware for 6 Axis Robotic Arm:

    I have had a go at modifying the RepRap firmware but i am getting insufficient axis homing messages and due to having 25:1 and 50:1 gear ratios at the joints

    This message has nothing to do with you gear ratios.
    And gear ratios doesn't need to be in the "firmware", just put the right steps per mm after calculating the gear ratio in.
    Reprap Firmware should easy handle you machine, they is just something wrong with you configuration. Probably your homing files are wrong. Pleas post them.



  • @dragonn

    For the Gear Ratios, do i simply multiply the Desired Steps Per mm (Say 80) by the gear ratio (25:1) to get a final Step Per mm of (80 * 25 = 2000)?

    Here is my Homeall.g:

    ; homeall.g
    ; called to home all axes
    ;
    ; generated by RepRapFirmware Configuration Tool v2 on Thu Feb 21 2019 16:57:55 GMT+0000 (Greenwich Mean Time)
    G91 ; relative positioning
    G1 Z5 F6000 S2 ; lift Z relative to current position
    G1 S1 X-405 Y-605 F1800 ; move quickly to X and Y axis endstops and stop there (first pass)
    G1 X5 Y5 F6000 ; go back a few mm
    G1 S1 X-405 Y-605 F360 ; move slowly to X and Y axis endstops once more (second pass)
    G1 S1 Z-605 F1800 ; move Z down stopping at the endstop
    G90 ; absolute positioning
    G92 Z-300 ; set Z to axis minimum (you may want to adjust this)

    ; Uncomment the following lines to lift Z after probing
    ;G91 ; relative positioning
    ;G1 S2 Z5 F100 ; lift Z relative to current position
    ;G90 ; absolute positioning



  • What mode are you in? Try to change all S parameters to H



  • @dragonn

    Having connected all motors it seems to be working now 🙂 Seeing as i will be using 6 motors for movement, do i just set X, Y and Z for 3 of them and E0, E1 and E2 for the other 3?



  • No, you need to configure new axes using M584 U, V and W axes


Log in to reply