Need Help!- Yet another joint 0 error thread

[margni74]

I'm trying to run some g code in axis with all power to the machine cut off.
Axis seems to have an issue when it hits the first G0 jog command and spits out a "joint 0 error" and then stops. My settings for jog speed are 31in/min, feed override arbitrarily set to 78% it that matters.

Each time it fails with Vel: 146.1600, Vel: 203.0472, or some other high number in the axis window. Why such a high number? Jog is set to 31in/min in the slider bar.

I changed the G0 line 3 times each time limiting the move to one less axis, and it continued to fail. Prior to each run I zeroed out x,y,z. It's another data point if nothing else.


1st run fails: G0 X0.992 Y1.008 Z0.15
2nd run fails: G0 X0.992 Y1.008
3rd run fails: G0 X0.992

If I comment out the G0 line, all 15000 lines in the program run without issue (all G1 commands).

Changing the first G0 to a G1 and slapping a feed rate of F5 on the end solves the problem.

[svenakela]

Try to run the same G-code with the parallel port cable removed from the computer. Joint 0 can pop up when there's a problem with the signals.
Did you disable home and end switches?

[margni74]

Originally Posted by svenakela Try to run the same G-code with the parallel port cable removed from the computer. Joint 0 can pop up when there's a problem with the signals. Did you disable home and end switches?

I'll give it a shot.

Yes, I disabled everything but the output signals for the X, Y, and Z axis.

[chester88]

Please post your INI file and/or your stepconf file if you used stepconf.

[margni74]

Originally Posted by chester88 Please post your INI file and/or your stepconf file if you used stepconf.

Here it is... btw, ive read that I may need to tweak the folowing 2 fields, but I have to clue what to change them to.

MIN_FERROR = 0.01
MIN_LIMIT = -20.0



# Generated by stepconf at Sun Aug 23 22:49:50 2009
# If you make changes to this file, they will be
# overwritten when you run stepconf again

[EMC]
MACHINE = 2axistest
NML_FILE = emc.nml
DEBUG = 0

[DISPLAY]
DISPLAY = axis
POSITION_OFFSET = RELATIVE
POSITION_FEEDBACK = ACTUAL
MAX_FEED_OVERRIDE = 1.2
INTRO_GRAPHIC = emc2.gif
INTRO_TIME = 5
PROGRAM_PREFIX = /home/scott/emc2/nc_files
INCREMENTS = .1in .05in .01in .005in .001in .0005in .0001in

[TASK]
TASK = milltask
CYCLE_TIME = 0.010

[RS274NGC]
PARAMETER_FILE = emc.var

[EMCMOT]
EMCMOT = motmod
SHMEM_KEY = 111
COMM_TIMEOUT = 1.0
COMM_WAIT = 0.010
BASE_PERIOD = 39000
SERVO_PERIOD = 1000000

[HAL]
HALFILE = 2axistest.hal
HALFILE = custom.hal
POSTGUI_HALFILE = custom_postgui.hal

[TRAJ]
AXES = 3
COORDINATES = X Y Z
LINEAR_UNITS = inch
ANGULAR_UNITS = degree
CYCLE_TIME = 0.010
DEFAULT_VELOCITY = 1.50
MAX_LINEAR_VELOCITY = 15.00

[EMCIO]
EMCIO = io
CYCLE_TIME = 0.100
TOOL_TABLE = tool.tbl

[AXIS_0]
TYPE = LINEAR
HOME = 0.0
MAX_VELOCITY = 6.5
MAX_ACCELERATION = 28.0
STEPGEN_MAXACCEL = 29.4
SCALE = 15240.0
FERROR = 0.05
MIN_FERROR = 0.01
MIN_LIMIT = -20.0
MAX_LIMIT = 20.0
HOME_OFFSET = 0.0

[AXIS_1]
TYPE = LINEAR
HOME = 0.0
MAX_VELOCITY = 15.0
MAX_ACCELERATION = 24.0
STEPGEN_MAXACCEL = 25.2
SCALE = 1587.5
FERROR = 0.05
MIN_FERROR = 0.01
MIN_LIMIT = -4.0
MAX_LIMIT = 4.0
HOME_OFFSET = 0.0

[AXIS_2]
TYPE = LINEAR
HOME = 0.0
MAX_VELOCITY = 6.41025641026
MAX_ACCELERATION = 30.0
STEPGEN_MAXACCEL = 31.5
SCALE = 4000.0
FERROR = 0.05
MIN_FERROR = 0.01
MIN_LIMIT = -2.0
MAX_LIMIT = 3.0
HOME_OFFSET = 0.0

STEPCONF file:
cant post it... xml issue maybe?

[samco]

I bet it is a stepgen headroom issue.

Increase the STEPGEN_MAXACCEL to be a good 20 - 30% over your MAX_ACCELERATION

So


[AXIS_0]
.
.
.
MAX_ACCELERATION = 28.0
STEPGEN_MAXACCEL = 29.4

should be

MAX_ACCELERATION = 28.0
STEPGEN_MAXACCEL = 36.4

[chester88]

your scale for axis 0 looks odd to me. It is a product of number of motor steps, microsteps, pulley teeth and leadscrew (TPI for imperial, pitch for metric).
Its very different from the other axis, is that right.
your max velocity for axis 1 is 900 inches a minute is that right?
Post your stepconf file on filebin.ca

Chris M

[margni74]

Originally Posted by samco I bet it is a stepgen headroom issue. Increase the STEPGEN_MAXACCEL to be a good 20 - 30% over your MAX_ACCELERATION So [AXIS_0] . . . MAX_ACCELERATION = 28.0 STEPGEN_MAXACCEL = 29.4 should be MAX_ACCELERATION = 28.0 STEPGEN_MAXACCEL = 36.4

Thanks, Ill hopefully be able to give this a try tomorrow.

Originally Posted by chester88 your scale for axis 0 looks odd to me. It is a product of number of motor steps, microsteps, pulley teeth and leadscrew (TPI for imperial, pitch for metric). Its very different from the other axis, is that right. your max velocity for axis 1 is 900 inches a minute is that right? Post your stepconf file on filebin.ca Chris M

Hmmm, Ill have to double check the figures, but from the configuration gui i think the max velocity for any of the axis was the y axis at around 300ipm.

Ill double check the number

thanks for the help guys.

[chester88]

I also see the MAX_LINEAR_VELOCITY = 15 (This controls max velocity)
it is in units per second, your units are inches so 15 inches per second
15 X 60 seconds = 900 inches per minute.
Also Jog speed slider won't affect G0 moves. Max Velocity slider will affect G0 moves.

Chris M

[svenakela]

And to all this, we had the same error on a step motor machine. After disconnecting the limit switches it ran fine. The switch cables weren't shielded and it caused faulty signals.