Galil DMC-1800 Position Tracking, Operand Summary - Independent Axis, Example - Jog in X only

Parameters can be set with individual axes specifiers such as JGY=2000 (set jog speed for Y axis to 2000).

Operand Summary - Independent Axis

OPERAND

_ACx

_DCx

_SPx

_TVx

DESCRIPTION

Return acceleration rate for the axis specified by ‘x’ Return deceleration rate for the axis specified by ‘x’ Returns the jog speed for the axis specified by ‘x’

Returns the actual velocity of the axis specified by ‘x’ (averaged over .25 sec)

Example - Jog in X only

Jog X motor at 50000 count/s. After X motor is at its jog speed, begin jogging Z in reverse direction at 25000 count/s.

#A
AC 20000,,20000	Specify X,Z acceleration of 20000 cts / sec
DC 20000,,20000	Specify X,Z deceleration of 20000 cts / sec
JG 50000,,-25000	Specify jog speed and direction for X and Z axis
BG X	Begin X motion
AS X	Wait until X is at speed
BG Z	Begin Z motion
EN

Example - Joystick Jogging

The jog speed can also be changed using an analog input such as a joystick. Assume that for a 10 Volt input the speed must be 50000 counts/sec.

#JOY	Label
JG0	Set in Jog Mode
BGX	Begin motion
#B	Label for loop
V1 =@AN[1]	Read analog input
VEL=V1*50000/10	Compute speed
JG VEL	Change JG speed
JP #B	Loop

Position Tracking

The Galil controller may be placed in the position tracking mode to support changing the target of an absolute position move on the fly. New targets may be given in the same direction or the opposite direction of the current position target. The controller will then calculate a new trajectory based upon the new target and the acceleration, deceleration, and speed parameters that have been set. The motion profile in this mode is trapezoidal. There is not a set limit governing the rate at which the end point may be changed, however at the standard TM rate, the controller updates the position information at the rate of 1msec. The controller generates a profiled point every other sample, and linearly interpolates one sample between each profiled point. Some examples of applications that may use this mode are satellite tracking, missile tracking, random pattern polishing of mirrors or lenses, or any application that requires the ability to change the endpoint without completing the previous move.

90 • Chapter 6 Programming Motion DMC-1700/1800