G38 + idex + multiple probes = insanity ?

crpalmer

I have an IDEX printer and each of the two tools has a its own probe (pz probes). These probes can trigger on contact in all 3 dimensions. I'm trying to take advantage of that fact to probe a pin with each tool to automatically configure the tool offsets.

As you'd expect, I have the standard X/Y/Z axes with a U axis which is mapping to X for tool 1.

I can probe Z successfully using either tool by activating the appropriate tool and specifying the corresponding probe # when running the G30 command. I can probe the pin successfully with T0 by running G38.2 commands. However, when I try to run G38.2 commands with T1 active, I get unexpected and inexplicable (to me) behaviour. Here is a series of commands I ran with a corresponding comment documenting what actually happened when I executed the command:

T0 G38.2 X150 K0   ; Moves X until probe 0 is triggered
T1 G38.2 X150 K1   ; Moves X & U until probe 1 is triggered
T0 G38.2 U150 K0   ; Moves U until probe 0 is triggered
T1 G38.2 U150 K1   ; Moves X until probe 1 is triggered
T1 G53 G38.2 U150 K1

The first line is what I'd expect (probe X by moving X when tool 0 is selected). The second command, however, is a mystery. To make sure G38.2 wasn't expectding unmapped axes to be specified, I also tried the G38.2 commands using the U axis which certainly didn't help me understand what was happening. Finally, I also tried machine coordinates for the U moves in case it was some discrepancy between machine positions vs. mapped axes (I can't say for sure what happened as I didn't record it in my notes but I expecdt it was the same as not using machine coordinates).

Any explanations or suggestions for accomplishing my goal of automatically aligning the tools?

My config.g is:

M98 P"/sys/global-declarations.g"

; General preferences
G90                                                    ; send absolute coordinates...
M83                                                    ; ...but relative extruder moves

; Drives
M569 P0 S0 ; D3                                        ; physical drive 0 goes backwards, stealthchop
M569 P1 S0 ; D3                                        ; physical drive 1 goes backwards
M569 P2 S0 ; D3                                        ; physical drive 2 goes backwards
M569 P3 S0 ; D3                                        ; physical drive 3 goes backwards
M569 P4 S0 ; D3                                        ; physical drive 4 goes backwards
M569 P1.0 S1 ; D3                                      ; physical drive 1.0 goes forwards
M569 P1.1 S1 ; D3                                      ; physical drive 1.1 goes forwards
M569 P1.2 S1 ; D3                                      ; physical drive 1.2 goes forwards
M584 X0.2 Y0.1:1.2 u1.1 E0.0:1.0 Z0.3:0.4              ; set drive mapping
M92 X160.00 Y160.00 U160.00 Z800.00 E680:680           ; set steps per mm (recommended; 690 orbiter)
M350 X16 Y16 U16 Z16 E16 I1                            ; set microstepping to 256 interpolation
M566 X600.00 Y600.00 U600.00 Z240.00 E300:300 P1       ; set maximum instantaneous speed changes (mm/min)
M203 X12000.00 Y12000.00 U12000.00 Z600.00 E7200:7200  ; set maximum speeds (mm/min)
M201 X1000.00 Y1000.00 U1000.00 Z500.00 E5000:5000     ; set accelerations (mm/s^2)
;M906 X1350 Y1350 U1350 Z1200 E850:850 I30              ; set motor currents (mA) and motor idle factor in per cent (orbiter supposed to be 1200)
M906 X1200 Y1000 U1200 Z840 I30                        ; Set motor currents (mA) and motor idle factor in per cent
M906 E850:850 I10                                      ; (orbiter supposed to be 1200)
M84 S30                                                ; Set idle timeout

; Z drive
;M671 X{global.xCenter, global.xCenter} Y-35:385 S2  			                   ; motor order: front, back
M671 X150:150 Y-35:385 S2  			                   ; motor order: front, back

; Axis Limits
M208 X0 Y-10 Z0 U-50 S1                       ; set axis minima
M208 X350 Y356 Z425 U305 S0                            ; set axis maxima

; Endstops
M574 X2 S1 P"^0.io5.in"                                ; configure active-high endstop for high end on X
M574 Y2 S1 P"^0.io6.in+^1.io0.in"                      ; configure active-high endstop for high end on Y
M574 U1 S1 P"^1.io2.in"                                ; configure active-high endstop for high end on U

; Z-Probe
M558 K0 P8 C"^!io1.in" R1.0 H5 F400 A5 T24000
G31  K0 X0 Y0 Z0 P25
M558 K1 P8 C"^!1.io5.in" R1.0 H5 F400 A5 T24000
G31  K1 X0 Y0 Z0 P25

M557 X0:325 Y5:355 P9                                  ; define mesh grid
M376 H2

; Filament sensor (BTT SFS 2.0)
M591 D0 P7 C"0.io3.in" L3 R50:150 E22 S1
M591 D1 P7 C"1.io1.in" L3 R50:150 E22 S1

; Pressure advance
M572 D0 S0.05
M572 D1 S0.05

; Fans (tool 0)
M950 F0 C"out5" Q250                                   ; create fan and set its frequency
M106 P0 S0 H-1                                         ; set fan value (off). Thermostatic control is turned off
M950 F1 C"out6" Q500                                   ; create fan and set its frequency
M106 P1 S1 T45 H1                                      ; set fan value (on). Thermostatic control is turned on

; Fans (tool 1)
M950 F2 C"1.out7" Q250                                 ; create fan and set its frequency
M106 P2 S0 H-1                                         ; set fan value (off). Thermostatic control is turned off
M950 F3 C"1.out6" Q500                                 ; create fan and set its frequency
M106 P3 S1 T45 H2                                      ; set fan value (on). Thermostatic control is turned on

; Fans (board cooling)
M950 F4 C"!1.out3" Q25000                              ; create fan and set its frequency
M106 P4 S1 H-1                                         ; set fan value (on).  Thermostatic control is turned off

; Bed Heater
M308 S0 P"temp0" Y"thermistor" T100000 B4092           ; configure sensor
M950 H0 C"out0" T0                                     ; create bed heater output and map it to sensor 0
M307 H0 R0.272 C349.6 D8.37 S1.00 V23.7
M140 H0                                                ; map heated bed to heater 0
M143 H0 S120                                           ; set temperature limit for heater 0 to 120C

; tool 0 thermistor
M308 S1 P"temp1" Y"thermistor" T100000 B4725 C7.06e-8  ; configure sensor
M950 H1 C"out1" T1                                     ; create nozzle heater output and map it to sensor 1

; tool 0
M307 H1 R3.927 K0.564:0.293 D1.73 E1.35 S1.00 B0 V24.1
M563 P0 S"E3Dv6" D0 H1 F0                              ; define tool 0
G10 P0 X0 Y0 Z0                                        ; set tool 0 axis offsets

; tool 1 thermistor
M308 S2 P"1.temp2" Y"thermistor" T100000 B4725 C7.06e-8; configure sensor
M950 H2 C"1.out2" T2                                   ; create nozzle heater output and map it to sensor 2

; tool 1
M307 H2 R3.401 K0.474:0.307 D1.67 E1.35 S1.00 B0 V24.2
M563 P1 S"E3Dv6" D1 H2 X3 F2                           ; define tool 1
G10 P1 U-1.61 Y-0.19 Z0.135                            ; set tool 1 axis offsets

; Set both tools to standby mode
M568 A1 P0 R0 S0
M568 A1 P1 R0 S0

; Tool (common)
G10 P0 R0 S0                                           ; set initial tool 0 active and standby temperatures to 0C
G10 P1 R0 S0                                           ; set initial tool 1 active and standby temperatures to 0C

; MCU DOES NOT WORK ON THE DUET 3 MINI 5+?
M912 P0 S-12.5                                         ; Calibrate MCU temperature

; Miscellaneous
M912 P0 S-1

M98 P"/sys/global-defaults.g"

and the full machine specific config can be found on github using common config found here.

Edit to add: running 3.5.4 on a SBC setup.

dwuk3d

@crpalmer

Doesn't make any sense to me looking at your configuration why moving X on T1 should move X1 and X2. and also why moving U on T1 is moving the wrong head X1 vs X2.

I can't see an M669 - so not sure what your kinematics are. Is there anything relevant in the two extra global files referenced at the start and end.

When you move the X and U with a G1, or when you move individual motors with a G1 H2 on either tool do they move as expected - is it only probing where they move incorrectly?

I presume that lower case 'u' in the M584 isn't causing any issues.

crpalmer

@dwuk3d To be clear, the printer itself is working well. I can print dual material/colour prints with it. I'm just running into difficulties when I am trying to add the pin probing functionality to it. All the axes move correctly, I can move X/U individually using G1 H2 (which I do as part of the tool cleaning process before probing Z or the pin).

The kinematics are plain old boring cartesian:

m669
Kinematics is Cartesian, no segmentation, matrix:
1.00 0 0 0
0 1.00 0 0
0 0 1.00 0
0 0 0 1.00

The reason for the global-* is that I have 5 printers which share 95% of their configuration in a common git repository to make maintaining them much simpler. The global configuration parameterizes the common functionality (e.g. the location of the wiping pad to use to clean the nozzle, where to move the tool when a print completes, etc). The links in the last line of the first post are to the machine repo (config.g and global-defaults.g) and the common config repo (all the rest of /sys/).

dwuk3d

Ok - beats me them why G38.2 isn't working - for my IDEX like printer I am using G1 H4's instead of G38's, and swapping probes and end stops around rather than using T commands.

Example attached is for a ball probe alignment on a Gantry with U (X) and V(Y) and it also uses Z to initially check it is on the probe - so not quite the same as your requirement - but might be of some use.

;AlignUVZ.g
;
;if exists(global.ballProbeX) == false
;    abort "XY alignment not found"

M98.1 A"Probe Out"

G90
T0
G1 Z50 F10000

G1 X30 Y30 F20000

M400
M98 P"0:/macros/FindProbeUV.g"
M574 Z1 S2 K3; Set Z to Ball Probe
G1 H4 Z{global.zHit-1} F300

if sensors.probes[3].value[0] = 0
    echo "Probe not found"
    break
;G1 U204 V149 F10000



; Find basic Z position

var Zpos = {50,49,48,48,48}
var Zrate = {300,200,100,100,100}
var Upos = {10,8,8,8,8}
var Vpos = {10,8,8,8,8}
var UVrate = {1000,800,300,300,300}

var prev = false
var pVM = 0
var pUM = 0

var VM=0
var UM=0


while iterations < 2
    M574 Z1 S2 K3; Set Z to Ball Probe

    G90
    G1 Z{var.Zpos[iterations]} F300
    G91 
    G1 H4 Z-12 F{var.Zrate[iterations]}
    ;echo "Z", {move.axes[2].userPosition}


    var ZP = move.axes[2].userPosition

    G1 Z5 F5000

    M574 Z1 S2 K0; configure Z axis endstop

    ; Now find U middle

    G91
    G1 U{0-var.Upos[iterations]} F2500
    G90
    G1 Z{var.ZP-0.2} F300


    G91
    M574 U1 S2 K3 ; Configure U axis with Z ball probe
    G1 H4 U+10 F{var.UVrate[iterations]}

    ;echo "X1", {move.axes[0].userPosition}
    M400
    var U1 = move.axes[3].userPosition

    G1 Z5 F300
    G1 U{var.Upos[iterations]}  F2500
    G1 Z-5 
    M400
    
    G1 H4 U-10 F{var.UVrate[iterations]}
    ;echo "X2", {move.axes[0].userPosition}
    M400
    var U2 = move.axes[3].userPosition

    G1 Z5

    G90
    set var.UM = (var.U1+var.U2)/2
   

    ;echo "XM", {var.XM}
    G1 U{var.UM}

    M574 U2 P"!122.io0.in" S1 ; configure U axis endstop

    ; Now V
    G91

    G1 V{0-var.Vpos[iterations]} F5000
    G1 Z-5 F300
    M574 V1 S2 K3

    G1 H4 V+10 F{var.UVrate[iterations]}
    ;echo "Y1", {move.axes[1].userPosition}
    M400
    var V1 = move.axes[4].userPosition

    G1 Z5 F300
    G1 V{var.Vpos[iterations]} F5000
    G1 Z-5 F300

    G1 H4 V-10 F{var.UVrate[iterations]}
    ;echo "Y2", {move.axes[1].userPosition}
    M400
    var V2 = move.axes[4].userPosition

    set var.VM = (var.V1 + var.V2) / 2

    echo "UM", {var.UM},"VM", {var.VM},"ZP", {var.ZP},"---U1,2",{var.U1},{var.U2},"--V1,2",{var.V1},{var.V2}
    if (var.prev == true)
        echo "variation U:",{var.pUM-var.UM}, "V:", {var.pVM-var.VM}
        
    set var.pVM = var.VM
    set var.pUM = var.UM
    set var.prev = true

    G1 Z5 F300

    G90 
    G1 U{var.UM} V{var.VM} F2000


    M574 V2 P"io4.in" S1 ; U Axis optical


M574 Z1 S2 K3; Set Z to Ball Probe
G91
G1 H4 Z-5 F300
var Z1 = move.axes[2].machinePosition
echo "z1",{var.Z1}

G1 Z5 F1000
G1 U4 F2500
G1 H4 Z-10 F300
var Z2 = move.axes[2].machinePosition
echo "z2",{var.Z2}

G1 U-4 F2500

G1 Z5 F1000

M574 Z1 S2 K0; configure Z axis endstop

if var.Z1-var.Z2 < 1
    echo "z1,z2",{var.Z1},{var.Z2}
    abort "possible issue with UV alignment"


if exists(global.ballProbeU) == false
    global ballProbeU = -1
    global ballProbeV = -1

set global.ballProbeU = var.UM
set global.ballProbeV = var.VM




G90
;var adjust = var.UM - global.ballProbeX
;echo "adjusting U",{global.ballProbeX - var.UM},"V",{global.ballProbeY - var.VM}
;G92 U{global.ballProbeX} V{global.ballProbeY}

;if exists(global.UVAdjusted) == false
;    global UVAdjusted = true

crpalmer

@dwuk3d Thanks for looking. I'm afraid it's a bug but I wanted to reach out here to see if anyone had experience doing something similar.

Unfortunately, I don't think I can use G1 H4 as I need to move X/Y until a probe is triggered, not the moving axis' endstop.

dwuk3d

@crpalmer OK - I am pretty new to RRF - and I am not really sure what the difference is between a probe and an endstop unless your probe is something analog.

I'm switching around the configuration between Inductive Probes, Ball probes and endstops in quite a few places in my homing and alignment macros - in fact I had to set one of my 5 probes as an end stop because I reached the limit on the maximum number of probes allowed.

droftarts

@crpalmer said in G38 + idex + multiple probes = insanity ?:

T0 G38.2 X150 K0 ; Moves X until probe 0 is triggered
T1 G38.2 X150 K1 ; Moves X & U until probe 1 is triggered
T0 G38.2 U150 K0 ; Moves U until probe 0 is triggered
T1 G38.2 U150 K1 ; Moves X until probe 1 is triggered

T1 G53 G38.2 U150 K1

The first line is what I'd expect (probe X by moving X when tool 0 is selected).
The second command, however, is a mystery.
To make sure G38.2 wasn't expectding unmapped axes to be specified, I also tried the G38.2 commands using the U axis which certainly didn't help me understand what was happening.
Finally, I also tried machine coordinates for the U moves in case it was some discrepancy between machine positions vs. mapped axes (I can't say for sure what happened as I didn't record it in my notes but I expecdt it was the same as not using machine coordinates).

Are you saying that, for the second command T1 G38.2 X150 K1, both tools are being moved? Because when any tool is mapped from it's usual axis (ie U) to X, it will update the position of both axes (even though only the U axis should physically move, the position on X is updated). If both X/T0 and U/T1 are physically moving, then yes, I'd think this was a bug.

Your third command doesn't make any sense to me, ie you're trying to use a tool and move the axis that is not associated with it. RRF will probably let you do this, just because someone will probably want that functionality at some point. Caveat operator!

I would imagine that your fourth command should work, but I'm not sure how the recorded position will relate to the X axis. I don't have an IDEX to test, to see what happens to the T1 X position when you command a U axis movement directly. I think what is supposed to happen with G1 moves is the the U axis will move independently, and the X axis position is not updated. However, when an X axis move is requested, the U axis will return to the previous position (where it left position with the X axis), then perform the expected X axis move, updating the U axis position as well. So it won't be useful for determining the X offset for T1.

If you can confirm this is what you see, I can raise it with @dc42.

Ian

crpalmer

@droftarts I tried all 4 combinations of U vs. X and specifying T0 vs. T1's probe to see if I could make any sense of it. I couldn't. I really don't want to run any strange combination of moving a tool and triggering a different endstop!

What I really want to run is "G38.2 X150 Kx " and have it move whichever tool is active toward 150 until probe #x is triggered. To confirm the behaviour I reported, I just ran the following sequence of commands:

G28
T0
G1 X150 F24000
T1
G1 X150 F24000
G1 X0
G38.2 X150 K1
G38.2 U150 K1

The G1 commands are to be 100% sure that the axes move as expected (T0 moves to 150 for the first G1 and then T1 moves to 150 for the second G1). The first G38.2 command moves both T0 and T1 until probe 1 is triggered. The second G38.2 command moves only T0 (T1 doesn't move even though it is both active and the tool driven by the U axis).

dc42

@crpalmer I confirm this is a bug. I have implemented a fix in the 3.6 source code, which will be in the next 3.6.0 RC or internal build I make available.

crpalmer

@dc42 Wow, that was a fast fix! Thanks!

dc42

@crpalmer I have provided main board firmware 3.6.0-rc.2+2 binaries at https://www.dropbox.com/scl/fo/nlkfneaas1osgtdw37s17/AIS_H0KSAKCmfYSjSRTSOAE?rlkey=ad4omnq36zkdz3wl8i7kthqqt&dl=0 which incude this fix.

crpalmer

@dc42 Again, thanks! I can confirm that this fixes my probing issue.