Examples and tips
PROGRAMMING MANUAL
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Example 5
fig. 17
With the feedforward set to 100%, the Following Error is very small and
proportional to the acceleration. The optimum value of 100% correction is
the maximum value that can be set. The parameter value of Pn109 is easier
to set than the parameter value of VFF_GAIN.
The parameter values for the example are:
/i
5.1.3
Setting the UNITS axis parameter and gear ratio
In controlling the mechanical axis with the Trajexia TJ2-MC64, a Servo
Driver and a servo motor, the only measurement units that the hardware
understands are encoder counts. All commands to the driver to move an
axis are expressed in encoder counts. All feedback information about axis
positions is also expressed in encoder counts. When writing programs in
BASIC to achieve movements or a sequence of movements, a user can
prefer to work with user defined units, such as millimeter, centimeter, meter,
degree of angle, "product", "rotation", "stations". The
UNITS
axis parameter
contains the conversion factor between encoder counts and user defined
units. All axis parameters related to motion and arguments of axis
commands that determine the amount of motion are expressed in these user
units. This parameter enables the user to define the most convenient units to
work with. For example, for a moving part that makes a linear motion, you
can prefer mm, or fraction of mm. For a moving part that makes a rotation
motion, you can prefer a degree of angle or its fraction. For more information
on the
UNITS
axis parameter, see section 3.2.299.
Motion Parameter values
Fn001=6
Pn109=100