Re: [CAD_CAM_EDM_DRO] Re: Need help and motors, and quickly...

On Tuesday 14 October 2003 1:30 am, Weyland wrote:
> They start to move, but lose most steps, growl,
> whine, and do everything _but_ dance (and move).

It sounds very much like the acceleration and velocity parameters are set too
high. Here are some figures snipped from a Sherline setup running freqmod at
20uSec period.


; Trajectory planner section
--------------------------------------------------
[TRAJ]

AXES = 3
COORDINATES = X Y Z
HOME = 0 0 0
LINEAR_UNITS = 0.03937007874016
ANGULAR_UNITS = 1.0
CYCLE_TIME = 0.010
DEFAULT_VELOCITY = 0.0167
MAX_VELOCITY = .3
DEFAULT_ACCELERATION = 8.0
MAX_ACCELERATION = 8.0

; First axis
[AXIS_0]

TYPE = LINEAR
UNITS = 0.03937007874016
HOME = 0.000
MAX_VELOCITY = 0.3
P = 220.000
I = 0.000
D = 0.000
FF0 = 0.000
FF1 = 0.000
FF2 = 0.000
BACKLASH = 0.001
BIAS = 0.000
MAX_ERROR = 0.000
DEADBAND = 0.00007
CYCLE_TIME = 0.001
INPUT_SCALE = -16000 0
OUTPUT_SCALE = -16000.000 0.000
MIN_LIMIT = -10.0
MAX_LIMIT = 10.0
MIN_OUTPUT = -10
MAX_OUTPUT = 10
FERROR = 1.000
MIN_FERROR = 0.010
HOMING_VEL = 0.1


Try these numbers with your machine and report back either via IRC or on
list. The Accel, Velocity, and P values are the ones we need to work on. The
scaling would of course be adjusted to suit your setup.

Regards, Paul.


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