Optimizing The Performance - ABB IRB 6620LX Product Manual

2.4.14 Optimizing the performance

Standard performance
The standard performance of a linear axis system should be more than enough
for most material handling applications. However if the application requires higher
accuracy, or if the installation is at the "weaker end" there are a number of
possibilities to improve the performance. Factors affecting the performance are
for example: height of the legs, position of the legs, length of the movement, speed,
robot arm position, tool design, and floor stiffness.
How to improve performance
Improve the stability of the installation
The most important factor is the configuration of the legs. Installations with long
distance between the legs in combination with high legs are more unstable. The
floor stability and attachment of the lower legs are also important factors. The
performance will in general be better when the robot is at a position close to a leg.
See Product specification - IRB 6620, and Product specification - Linear Axis.
Reduce the acceleration
The instruction AccSet can be used in the RAPID program to temporarily reduce
the acceleration and thus vibration of the system. This is especially efficient during
shorter movements.
For example, AccSet 50, 25 will limit the acceleration to 50% of the normal value
and the ramp (acceleration rate) to 25% of the normal value.
Use reduced acceleration during the more sensitive movements and increase the
value to the default (AccSet 100, 100) during longer movements or when the
need of accuracy is less important.
For more information about AccSet see Technical reference manual - RAPID
Instructions, Functions and Data types.
Product manual - IRB 6620LX
3HAC035737-001 Revision: P
CAUTION
If two IRB 6620LX are mounted on the same linear axis, then they may influence
each other causing vibrations. Therefore, is the securing of the frame support
extra important for applications where even small vibrations can cause
disturbances.
© Copyright 2009-2018 ABB. All rights reserved.
2 Installation and commissioning
2.4.14 Optimizing the performance
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