Basic Characteristics RAPID

equired to obtain the same force.
The softness parameter is set in the program and it is possible to change the softness
values anywhere in the program. Different softness values can be set for different joints
and it is also possible to mix joints having normal servo with joints having soft servo.
Activation and deactivation of soft servo as well as changing of softness values can be
made when the robot is moving. When this is done, a tuning will be made between the
different servo modes and between different softness values to achieve smooth
transitions. The tuning time can be set from the program with the parameter ramp. With
ramp = 1, the transitions will take 0.5 seconds, and in the general case the transition
time will be ramp x 0.5 in seconds.
Note that deactivation of soft servo should not be done when there is a force between
the robot and the work object.
With high softness values there is a risk that the servo position deviations may be so
big that the axes will move outside the working range of the robot.
2.6 Path Resolution
The robot has a parameter named “path resolution”, which can be used in robot
installations having external axes with long deceleration times. In such applications the
warning “50082 Deceleration too long” will be reported, simultaneously generating a
quick-stop. The path resolution parameter will then need to be increased until the
problem disappears.
The need for tuning the path resolution parameter will increase when:
• The acceleration value of an external axis (and the robot) is decreased (Acc Set, first
parameter)
• The acceleration derivative is decreased (Acc Set, second parameter)
• The speed is increased
• The distance between close programmed positions are decreased
• The number of simultaneously controlled axes is increased
• Coordinated interpolation is used.
It is important to use a path resolution value which is as small as possible to achieve a
high path resolution also at high speed.
2.7 Stop and restart
A movement can be stopped in three different ways:
1. For a normal stop the robot will stop on the path, which makes a restart easy.
2. For a stiff stop the robot will stop in a shorter time than for the normal stop, but the
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