the stepper motors stutter a bit with maxaccel=0... :-(
i think they can't handle the per-servo-loop accelerations, especially at high speed (cruis)
is the AXIS_N setting correct for the motors/drives?
step timing and [AXIS]MAX_VELOCITY are correct for the stepper driver
what happens if you lower the [AXIS]MAX_ACCEL a little?
it's maybe a little better
but the problem is not during accel or decel, it's during cruise
does a ddt on the position output show anything?
(should be a nice flat line)
when there's no accel limit, the stepgen shouldn't bother doing any accel math at all - it should just calculate the number of steps needed in one period, and set the rate generator to that number
give or take 1 :)
subject to maxvel
ddt of pos-fb isn't perfectly flat, i think it's having a hard time matching both vel & pos, so it weaves around a bit
i think this "weaving" is causing more accel than the motor can deliver
I was thinking you should look at cmd-pos, just to be absolutely sure you know it's not the TP
(I'm sure it's not, but it helps to be sure)
it's not TP, it's me ;-)
i was looking at axis.N.joint-vel-cmd, which i think should be the same as (or better than) ddt(axis.N. position-cmd)
joint-vel-cmd is rock-steady at the configured [AXIS] maxvel
well, it should be, but that's not the input to stepgen
I'd look at a ddt on joint-pos-cmd, which I'm sure is also rock steady
but it's like metering your lab power supply voltage before troubleshooting your circuit - just peace of mind
yeah, good point
* cradek hides
noworries, I'm sure it's not your fault
you can probably go (back) to sleep
conveniently, my [AXIS] maxvel is 10, so i can tell by looking at datapoints in the halscope trace that it's incrementing by .001 for each 1 ms servo loop
it's not cradek, it's me
EMC: 03cmorley 07TRUNK * 10emc2/configs/common/configurable_options/pyvcp/parportpanel.xml: add parport test panel for pncconf
$2.99 for wifi!?
just like the motel!
let me know ho breakfast is :)
hmmm. or not. you are in Iowa
I think breakfast is coffee, and is included in the $31 cost.
powdered or liquid cream, what do you think?
powdered vegetable oil, of course
as long as there's sugar in it too, it should be all rigth
(I kind of like the taste of Cremora, but not in coffee)
sorry - you guys were devel-ing emc...
necer heard of it
oh. cremora is to cream as Coffee Mate is to milk
the possibility exists that i have shitty stepper motors
it's sitting loose on my workbench
if i grab the motor body when i command it to move, it moves
if i release the motor body, it just whines
if pos-fb is jittery and pos-cmd isn't, then it doesn't matter if you have motors attached at all
though they do make good audible indicators of performance
does the mesa encoder have an up/down mode?
if so you could loopback
(sorry if that's obvious...)
the encoder has up/down, and the stepgen has quadrature ;-)
isn't there a wuadrature output mode for the stepgens?
EMC: 03cmorley 07TRUNK * 10emc2/src/emc/usr_intf/pncconf/ (pncconf.py pncconf.glade):
EMC: Fix method: make_piname to add proper HAL pin name endings (such as .in_not)
EMC: Add the start of a test panel for the parport page
have i mentioned yet tonight that i like halscope?
hmmm. lemme check my scrollback :)
ugh - save it for another night
EMC: 03bigjohnt 07TRUNK * 10emc2/docs/src/hal/images/ (signal-direction.odg signal-direction.png): add image
EMC: 03bigjohnt 07TRUNK * 10emc2/docs/src/hal/basic_hal.lyx: expand a bit on signal direction
EMC: 03bigjohnt 07v2_3_branch * 10emc2/docs/src/hal/images/ (signal-direction.odg signal-direction.png): add image
EMC: 03bigjohnt 07v2_3_branch * 10emc2/docs/src/hal/basic_hal.lyx: expand on pin direction