Transcript Document

The 14th International DAAAM Symposium "INTELLIGENT MANUFACTURING & AUTOMATION:
FOCUS ON RECONSTRUCTION AND DEVELOPMENT“ (DAAAM - 2003)
22-25th October 2003, Sarajevo, Bosnia and Herzegovina
INTEGRATION OF CONTROL SYSTEMS OF
AUTOMATIC ASSEMBLY CELL AND ROBOTS
AS TRANSACTIONAL ANALYSIS ISSUE
Davor ZORC
Zoran KUNICA
Božo VRANJEŠ
Faculty of Mechanical Engineering and Naval Architecture
University of Zagreb
Croatia
INTRODUCTION
Integration of equipment of different manufacturers frequent task in design and realisation of automatic
systems.
Moreover, intensive technological development and
manufacturing reality often imply that the mentioned
task includes integration of different technological
generations of equipment.
“System integration” and “system integrators” are
terms which usually mark that kind of engineering
work.
Integration implies several levels, both hardware and
software, design and control.
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The paper is based on the requirement of equipment
integration in the Laboratory for Intelligent Production
Systems (LIPS) of the Faculty of Mechanical
Engineering and Naval Architecture, University of
Zagreb.
The focus will be given to the integration of control
systems of the equipment, which are due to their
function and design entirely separated.
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EQUIPMENT AND WORKING PROCESS
Disassembled and assembled product
Festo automatic assembly cell (1992)
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Robot AdeptSix 300 (2002)
Mobile robot Pioneer2 (2002)
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Feature
Festo station
Adept robot
Mobile robot
Production year
1991
2001
2001
controller
Festo PLC
FPC404
MV-5
Siemens
88C166
number of
inputs/outputs
40/16 + 4 step
motor
positions
44/40
8/8
controller
operating system
-
V+
P2OS
monitoring PC
operating system
MS-DOS
MS-Windows
Linux or
Windows
application
software
FST404
V+
Saphira
application
language
STL
V+
C/C++
TCP/IP supported
no
yes
yes
The features of the equipment
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INTEGRATION APPROACHES
The integration of the equipment is possible in several
ways.
There are especially many possibilities in achieving
connection between Festo station and Adept robot that
should be addressed, because of the time/technology
generation gap (older Festo vs. newer robots).
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1. Manual integration.
Human operator launches robot programs for loading/unloading
of the base part and finished assembly.
This kind of integration is sufficient for testing only.
2. Integration based on timers incorporated into Adept's
control programs.
The robot waits the Festo station operations to be completed.
Either this kind of integration is not sufficient for
regular use. Namely, the robot does not 'know' whether
Festo's operations are successfully completed.
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3. Involving sensors into robot's control environment,
by adding two sensors which monitor presence of the base part
on the conveyor and finished assembly on the rotary table.
The robot acts appropriately, however, the robot's
and Festo's control systems are still entirely
separated.
4. Sharing of sensors' data between Festo station and
robot.
Robot's controller catches Festo's input signals. Additional
electronic hardware is necessary to facilitate data collecting.
Earlier duplication of sensors, is replaced by
duplication of electronic circuits now.
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5. General purpose bidirectional port-to-port
connection between Festo's and Adept's controllers.
Festo's controller does not have any free port
connection.
6. Ethernet based communication between PCs, where
each of them controls station/robot.
This solution requires appropriate control programs with
instructions for reading/writing network messages.
In the case of Festo's old PLC it is not supported.
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7. The use of internet custom protocols.
Adept supports such method, but only for
communication with Adept's certified equipment.
8. Internet-based communication through FTP protocol
(standard on any newer operating system/platform).
Since the Festo's controller is MS-DOS driven, the requirement
for file transfer may be achieved by writing status file on local
disk. Station's program should involve commands for writing
status files, and robot's program should include commands for
accessing and reading files on Festo's PC.
However, there is no possibility for writing files in
Festo's old software.
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9. Acquiring new-generation PLC for Festo station.
On the basis of the previous considerations, it may be
finally concluded that the most effective solution is that
given under 9., while the easiest and almost instantly
achievable is that under 3 (duplication of sensors).
Robot and mobile robot, as newer pieces of
equipment, are ready to fully utilise TCP/IP protocol.
After implementation of the TCP/IP protocol, the
equipment will be fully integrated into single system in
the sense of information flow – and as such,
controllable through Internet from any location.
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INTEGRATION AS TRANSACTIONAL
ANALYSIS ISSUE
Technical sciences are faced with emerging
technologies and paradigms (including biological science,
miniaturisation, ethics and uncovered aspects of human mind).
Vast mankind's knowledge base calls for synthesis
and compiling.
Each domain cannot be self-centric any more –
diversified knowledge is necessary: various
engineering knowledge and knowledge from outside
the traditional engineering domain and practice.
Mentioned has inspired us to explore the possibilities
of using Transactional Analysis (TA) in solving control
issues in technical systems.
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TA was introduced in the fifties years of the 20th
century by Eric Berne.
Transactional Analysis is (Steiner, 2003) :
1.) an easily understandable yet sophisticated
psychological theory about people's thinking, feelings
and behavior and,
2.) a contemporary and effective system of
psychotherapy, education, organizational and sociocultural analysis and social psychiatry. ...
3.) People's interactions are made up of transactions.
Any one transactions has two parts: the stimulus and
the response. ... Stroking is the recognition that one
person gives to another. ... are essential to a person's
life. ... positive strokes like praise or expressions of appreciation,
or negative strokes like negative judgements or put downs. ... the
exchange of strokes is one of the most important thing
that people do in their daily lives.
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There is a clear analogy between the latter and any
technical system. The “stroke” concept for our
technical system is represented beneath.
Adept robot
unload
load
Festo station
magazine conveyor
unload
table
load
load
pallet
unload
Mobile robot
The strokes – transactions among
equipment
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The future work would try to identify other similarities
in TA that could be useful for solving more and more
complex transactions among incoming technical
systems.
The further details & arguments on the possible use of
TA:
- growing complexity of technical systems assumes
that their behaviour should have several layers, as
humans have, in the sense of efficiency,
- TA offers a concept of ‘GAMES’ – structured
behaviours and scenarios,
- though that concept is not the paramount of the
human capabilities and qualities, at the moment, it is
very applicable in the effort to be imitated by a
technical system.
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