Delta RMC151 - Manual (Page 786)

RMC70/150 and RMCTools User Manual
Curve Data
The Curve Data parameter specifies the starting address of the curve data in the
Variable Table. For details on the curve data, see the Curve Data Formats topic.
For all the Curve Formats, the first item in the curve data is the Curve Status. Because it
is the first item, the Curve Status is located at the address specified by the Curve Data
parameter. The RMC reports the state of the curve processing in this Curve Status
register. Adding a curve requires some processing time that typically exceeds one loop
time. It is important to not try to use a curve until it has been processed and added to
the Curve Store. When the Curve Status is 3, the curve has been added to the Curve
Store and is ready to use.
The following Curve Status values are defined:
• (0) Processing Not Started
By convention the user may want to set this register to this value before issuing the
command. This is not strictly necessary, but otherwise the user must make sure not to
check this register until after the command has been received.
• (1) Processing
Once the command has been received, the Status will immediately be set to
Processing. While in this state the command is currently using the Curve Data
structure, and the curve is not ready for interpolation.
• (2) Part Complete
Very long curves can be submitted in parts, as described in the Adding Large Curves
topic. Once the command has completed processing this Curve Data structure (i.e. this
part of the total curve), this status value will be used. The user can now write down
the next part of the curve.
• (3) Curve Ready
Once the curve data has been processed, and the entire curve is ready for
interpolation, the status will be set to this value. Notice that this value will also be
used for the final part for long curves submitted in parts. Therefore, for the last part of
a curve, the Part Complete (2) state won’t be used—the status will change directly
from Processing (1) to Curve Ready (3).
• (10+) Error
Values of 10 and above will indicate various errors. When an error code is set in this
register, it indicates that the command is done trying to process this Curve Data, but
the curve was not submitted to the curve store. See the Curve Status Error Codes
topic for a list of possible error values.
Interpolation Method
For the Interpolation Method parameter, choose from one of the methods below. The
Cubic (2) method is the most common method and creates the smoothest motion.
• Cubic (2)
The curve will smoothly go through all points. This is the most common
interpolation method. This method will create smooth motion.
On position axes, the Velocity Feed Forward and Acceleration Feed Forward will
apply to cubic interpolated curves, but higher order gains should not be used, such
as the Jerk Feed Forward, Double Differential Gain, and Triple Differential Gain.
On pressure or force axes, the Pressure/Force Rate Feed Forward will apply.
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