Basic Characteristics RAPID

Low resolution together with stiff tuned controller can result in unacceptable torque,
noise and controller instability. Check the controller tuning and axis performance close
to the working range limit at installation. Also check if the position resolution and path
performance are acceptable.
2.4.5 Speed and acceleration
In manual mode with reduced speed, the speed is reduced to the same level as if the axis
was running as non-independent. Note that the IndSpeed\InSpeed function will not be
TRUE if the axis speed is reduced.
The VelSet instruction and speed correction in percentage via the production window,
are active for independent movement. Note that correction via the production window
inhibits TRUE value from the IndSpeed\InSpeed function.
In independent mode, the lowest value of acceleration and deceleration, specified in the
configuration file, is used both for acceleration and deceleration. This value can be
reduced by the ramp value in the instruction (1 - 100%). The AccSet instruction does
not affect axes in independent mode.
2.4.6 Robot axes
2.5 Soft Servo
Only robot axis 6 can be used as independent axis. Normally only the IndReset
instruction is used for this axis.
If axis 6 is used as an independent axis, singularity problems may occur because the
normal 6-axes coordinate transform function is still used. If a problem occurs, execute
the same program with axis 6 in normal mode. Modify the points or use SingArea\Wrist
or MoveJ instructions.
The axis 6 is also internally active in the path performance calculation. A result of this
is that an internal movement of axis 6 can reduce the speed of the other axes in the
system.
The independent working range for axis 6 is defined with axis 4 and 5 in home position.
If axis 4 or 5 is out of home position the working range for axis 6 is moved due to the
gear coupling. However, the position read from teach pendant for axis 6 is compensated
with the positions of axis 4 and 5 via the gear coupling.
In some applications there is a need for a servo, which acts like a mechanical spring.
This means that the force from the robot on the work object will increase as a function
of the distance between the programmed position (behind the work object) and the
contact position (robot tool - work object).
The relationship between the position deviation and the force, is defined by a parameter
called softness. The higher the softness parameter, the larger the position deviation
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