Push to extend bug?

Troubleshooting
41

Both , after the full install it lost our config so setup its own AP. Same result with that.

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42

Does the zaxis work normally?

43

Watching the video again it clearly shows that itā€™s working backwards. Like as if the encoder somehow is confused about which way is out. But then the logs look normal :confused:

44

Yup. Itā€™s going up and down without issue

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45

Actually Iā€™m not so sure about this. Looking at the code it seems like it should work exactly the way that it is working for you:

float distMoved   = positionNow - lastPosition;

    //If the belt is moving out, let's keep it moving out
    if (distMoved > .1) {

My machine is at the shop so I wonā€™t be able to test until tomorrow but it sure does seem like somehow everything is backwards

46

When this happened a few weeks ago usually a reboot or firmware upgrade would resolve it. Iā€™ve put 10+ hours of cutting on the machine and itā€™s been millimeter perfect. Soooo weird

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47

Super weird for sure! Weā€™ll get to the bottom of it.

I feel like Iā€™ve got some good leads to jump into tomorrow morning

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48

OK, so comparing your log to my log it is 100% that somehow it thinks its going backwards:

Position: -55.774

vs

Position: 375.602

Now we just need to figure out how that is possible

49

Hereā€™s a version which tells us more about all the relevant parts of that calculation:

firmware.bin (1.6 MB)

It also includes one possible fixā€¦we were using a float where we should have been using an int32_t. They are the same size in memory (I think) so they shouldnā€™t be causing the issue that we are seeingā€¦but also compiler magic happens and who knows.

For comparison on my machine this starts out looking like this:

[MSG:INFO: Position: 0.011 mostRecentCumulativeEncoderReading: -1 _mmPerRevolution: 43.975]

Looks like this while Iā€™m pulling on the belt:

[MSG:INFO: Position: 18.176 Distance moved: 1.729 on axis Top Left]
[MSG:INFO: Position: 18.176 mostRecentCumulativeEncoderReading: -1693 _mmPerRevolution: 43.975]
[MSG:INFO: Position: 19.239 Distance moved: 1.063 on axis Top Left]
[MSG:INFO: Position: 19.239 mostRecentCumulativeEncoderReading: -1792 _mmPerRevolution: 43.975]

And ended up looking something like this:

[MSG:INFO: Position: 347.205 mostRecentCumulativeEncoderReading: -32340 _mmPerRevolution: 43.975]
50

tl2.rtf (40.6 KB)
see attached

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51

OK so the encoder is 100% reading backwardsā€¦hmmm

52

Digging into the encoder code it looks like it is possible to set the encoder to read backwardsā€¦weā€™re not doing that but maybe itā€™s getting set somehow anyway? Hereā€™s a version which will print out if that is happening:

firmware.bin (1.6 MB)

Edit:

[MSG:INFO: Encoder direction: 0]

Is what we expect to see

53

tl3.rtf (64.7 KB)
thats what we seeā€¦

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54

It seems like there is some sort of bug in the encoder code because I tried to set the encoder direction backwards to see if I could replicate what you are seeing and it works exactly the same for me either wayā€¦which it shouldnā€™tā€¦investigating

55

Will you DM me your address? I want to send you a couple spare encoders in case it turns out to be an issue with the encoder board and I want to get those in the mail

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56

Until I can find the true cause of the issue hereā€™s a quick fix which will reverse the direction of the encoders hopefully helping to fix the issue:

firmware.bin (1.6 MB)

57

All 4 arms extending the correct way! Is it safe to cut do you think?

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58

Weā€™re in uncharted territory. Iā€™d jog it around for a bit and see if it behaves as expected first

59

So far so goodā€¦ jogged around a sheet of 2400x1200 without issue. :crossed_fingers:

Serial Messages
[MSG:INFO: Channel auto report interval set to 50 ms]
[GC:G0 G54 G17 G21 G90 G94 M5 M9 T0 F0 S0]
[GC:G0 G54 G17 G21 G90 G94 M5 M9 T0 F0 S0]
[MSG:INFO: Caution: Unlocked]
[MSG:INFO: Retracting all belts]
[MSG:INFO: Bottom Left pulled tight with offset 0.011]
[MSG:INFO: Top Left pulled tight with offset 0.000]
[MSG:INFO: Bottom Right pulled tight with offset 0.000]
[MSG:INFO: Top Right pulled tight with offset 0.000]
[MSG:INFO: Extending all belts]
[MSG:INFO: Retracting all belts]
[MSG:INFO: Top Left pulled tight with offset 0.000]
[MSG:INFO: Bottom Left pulled tight with offset 0.011]
[MSG:INFO: Top Right pulled tight with offset -0.011]
[MSG:INFO: Bottom Right pulled tight with offset -15.310]
[MSG:INFO: Extending all belts]
[MSG:INFO: All belts extended to center position]
[MSG:INFO: Measured waypoint 0]
[MSG:INFO: Center point deviation: TL: 0.054 TR: 0.020 BL: -2.991 BR: -3.071]
[MSG:INFO: Center point deviation: TL: 0.054 TR: 0.020 BL: -2.991 BR: -3.071]
[MSG:INFO: Center point deviation within 15.000mm, your coordinate system is accurate]

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60

Keep me posted. Iā€™ll keep investigating.