Calculating Controller Data; Controller Data - Default Setting; Auto Servo Tuning (Ast) For The Robot Axes - Siemens SINUMERIK 840D sl Commissioning Manual

5.7

Calculating controller data

5.7.1

Controller data - default setting

Within the scope of commissioning of a supported robot from Comau, the controller data (speed
and position controller) is set, in addition to all of the relevant axis and motor data. The
parameters used for this form an optimal setting, taking the following boundary conditions into
consideration:
● The control loops are stable in the entire working area of the robot.
● The control loops are stable for all and any payloads and add-on loads within the scope of
the specification of the Comau documentation "Technical Specification".
The controller parameterization used corresponds to a so-called "damping-optimized" setting.
As a result, the best possible damping of the respective first natural frequency is achieved.
During the commissioning, the controller data is written to the first 2 data sets (Index 0 and 1).
The second data set has no functional relevance at first. The second data set is used
exclusively as a backup in the event that the data is overwritten, by the "Auto Servo Tuning"
function for example.
References
Comau documentation "Technical Specification"
5.7.2

Auto Servo Tuning (AST) for the robot axes

With SINUMERIK 840D sl Auto Servo Tuning (AST), an optimal controller setting can be
automatically determined for a feed axis. This optimal controller setting is relative to the
measured dynamic response of the axis in a specific operating point (= pose + payload). The
dynamic response of the robot axes can change very dramatically depending on the pose and
the payload. This is not taken into consideration by AST, however.
● If AST is carried out in a "dynamically disadvantageous" pose, e.g. with the robot arm
extended, this can lead to an unstable condition of the speed control loop when the robot
arm is retracted.
● If AST is carried out in a "dynamically advantageous" pose, e.g. with the robot arm retracted,
this can lead to an unstable condition of the speed control loop when the robot arm is
extended.
The use of AST on the robot arm is only possible in individual cases, assuming the working area
is extremely limited. For automatic controller optimization, the robot should be positioned
approximately in the center of the working area.
If you perform the controller parameterization for an individual axis with AST, the interpolation
behavior of the axis group is changed at first. To correct the interpolation behavior, you must
equalize the parameterization of the setpoint channel in all axes (see Section Interpolating
special axes (Page 54)).
SINUMERIK Run MyRobot /Direct Control
Commissioning Manual, 12/2018, A5E45238414B AB
Commissioning
5.7 Calculating controller data
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