Basic Characteristics RAPID

Positioning during Program Execution Motion and I/O Principles
Figure 16 Circular interpolation with a long twist for orientation is achieved by defining the
orientation in the circle point in the opposite direction compared to the start point.
As long as all motor torques do not exceed the maximum permitted values, the tool will
move at the programmed velocity along the arc of the circle. If the torque of any of the
motors is insufficient, the velocity will automatically be reduced at those parts of the
circular path where the motor performance is insufficient.
All axes are coordinated in order to obtain a path that is independent of the velocity.
Acceleration is optimised automatically.
2.2.4 SingArea\Wrist
Circle point
Start point
During execution in the proximity of a singular point, linear or circular interpolation
may be problematic. In this case, it is best to use modified interpolation, which means
that the wrist axes are interpolated axis-by-axis, with the TCP following a linear or
circular path. The orientation of the tool, however, will differ somewhat from the
programmed orientation.
In the SingArea\Wrist case the orientation in the circle support point will be the same
as programmed. However, the tool will not have a constant direction relative to the
circle plane as for normal circular interpolation. If the circle path passes a singularity,
the orientation in the programmed positions sometimes must be modified to avoid big
wrist movements, which can occur if a complete wrist reconfiguration is generated
when the circle is executed (joints 4 and 6 moved 180 degrees each).
2.3 Interpolation of corner paths
Destination point
The destination point is defined as a stop point in order to get point-to-point movement.
This means that the robot and any external axes will stop and that it will not be possible
to continue positioning until the velocities of all axes are zero and the axes are close to
their destinations.
Fly-by points are used to get continuous movements past programmed positions. In this
way, positions can be passed at high speed without having to reduce the speed
unnecessarily. A fly-by point generates a corner path (parabola path) past the programmed
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