Gemini GV6K and Gemini GT6K Programmer's Guide

Positioning Modes
The Gem6K controller can be programmed to position in either the preset (incremental or
absolute) mode or the continuous mode. You should select the mode that will be most
convenient for your application. For example, a repetitive cut-to-length application requires
incremental positioning. X-Y positioning, on the other hand, is better served in the absolute
mode. Continuous mode is useful for applications that require constant movement of the load
based on internal conditions or inputs, not distance.
Refer also to the
Scaling section on
page 67.
Positioning modes require acceleration, deceleration, velocity, and distance commands
(continuous mode does not require distance). The table below identifies these commands and
their units of measure, and which scaling command affects them.
Parameter Units (Unscaled), Stepper Units (Unscaled), Servo Unit Scaling Command *
Acceleration revs/sec 2 encoder/resolver: revs/sec 2 SCLA
Deceleration revs/sec 2 encoder/resolver: revs/sec 2 SCLA
Velocity revs/sec encoder/resolver: revs/sec SCLV
Distance steps counts SCLD ***
* Scaling must first be enabled with the SCALE1 command. For details on scaling, refer to page 67.
*** An axis assigned as a master (for Following) is scaled by the SCLMAS command.
On-The-Fly (Pre-emptive Go) Motion Profiling
While motion is in progress (regardless of the positioning mode), you can change these
motion parameters to affect a new profile:
• Acceleration (A) — s-curve acceleration not allowed during on-the-fly changes
• Deceleration (AD) — s-curve deceleration not allowed during on-the-fly changes
• Velocity (V)
• Distance (D)
• Preset or Continuous Positioning Mode Selection (MC)
• Incremental or Absolute Positioning Mode Selection (MA)
• Following Ratio Numerator and Denominator (FOLRN and FOLRD, respectively)
The motion parameters can be changed by sending the respective command (e.g., A, V, D,
MC, etc.) followed by the GO command. If the continuous command execution mode is
enabled (COMEXC1), you can execute buffered commands; otherwise, you must prefix each
command with an immediate command identifier (e.g., !A, !V, !D, !MC, etc., followed by
!GO). The new GO command pre-empts the motion profile in progress with a new profile
based on the new motion parameter(s).
For more information, see On-The-Fly Motion Profiling on page 155.
Chapter 3. Basic Operation Setup 71