APPLICATION OF A HUMAN FACTOR GUIDELINE TO
SUPERVISORY CONTROL INTERFACE IMPROVEMENT
Pere Ponsa, Ramon Vilanova
Automatic Control Department, Technical University of Catalonia, Av. Victor Balaguer s/n
08800 Vilanova i la Geltrú, Spain
Telecomunication and Systems Engineering Department, Universitat Autónoma de Barcelona
ETSE, 08913 Bellaterra, Spain
Marta Díaz, Anton Gomà
4all-L@b Usability Laboratory, Technical University of Catalonia, Av. Victor Balaguer s/n
08800 Vilanova i la Geltrú, Spain
S.A.F. Sports Service Area, Universitat Autónom
a de Barcelona
ETSE, 08913 Bellaterra, Spain
Keywords: Supervisory control, user interface design, human computer interaction.
Abstract: In tasks of human supervision in industrial control room they
are applied generic disciplines as the software
engineering for the design of the computing interface and the human factors for the design of the control
room layout. From the point of view of the human computer interaction, to these disciplines it is necessary
to add the usability engineering and the cognitive ergonomics since they contribute rules for the user
centered design. The main goal of this work is the application of a human factors guideline for supervisory
control interface design in order to improve the efficiency of the human machine systems in automation.
This communication presents the work developed to improve the Sports Service Area interface of the
Universitat Autónoma de Barcelona.
1 INTRODUCTION
In recent years, control systems and the role of
control room human operators have changed
dramatically. Human operator activity has evolved
from manually performing the process, to control
system supervision. Today, the human operator
requires an in-depth knowledge of the process that
he/she is overseeing and the ability to make effective
decisions within demanding constraints.
The increased complexity of i
ndustrial process
control calls for a new methodological approach (for
research and design purposes), which reproduces the
essential components of current control systems: the
environment, the task at hand and human operator
activity (Samad and Weyrauch, 2000).
The complexity of industrial process supervision
mak
es it necessary to supplement the Human Factors
approach and the Human-Computer Interaction
approach with a cross-disciplinary cooperation in
order to integrate knowledge and methods from
other fields, especially Cognitive Ergonomics,
Automation and Artificial Intelligence (Granollers
et. al., 2005), (Holstom, 2000) (Petersen, 2000). Our
view is that complete control systems engineering
must encompass all these approaches.
Ergonomics is concerned with the adaptation of
tech
nology to suit human operator need and ability
so as to achieve effectiveness, efficiency and
user/worker satisfaction and comfort (Cañas, 2004).
Supervisory control is the set of activities and
t
echniques developed over a set of controllers
(programmable logic controllers and industrial
regulators) which ensures the fulfilling of control
goals. One of the main goals is to prevent possible
plant malfunctions that can lead to economical lose
and/or result in damage (Petersen and May, 2006).
For this reason, other fields of knowledge concerned
with manufacturing systems performance – such as
161
Ponsa P., Vilanova R., Díaz M. and Gomà A. (2007).
APPLICATION OF A HUMAN FACTOR GUIDELINE TO SUPERVISORY CONTROL INTERFACE IMPROVEMENT.
In Proceedings of the Fourth International Conference on Informatics in Control, Automation and Robotics, pages 161-168
DOI: 10.5220/0001641201610168
Copyright
c
SciTePress
maintenance and industrial security – are
complementary in the study of supervision systems.
In this paper a methodology for the creation of a
human factor guideline for supervisory control
interface design is proposed. In section 2 we present
a checklist of indicators of the guideline called
‘ergonomic guideline for supervisory control
interface design (GEDIS Guia ergonómica para el
diseño de interfaz de supervision in Spanish
version). The Sports Service Area project is
described in section 3. The purpose is not to cover
with detail the entire project but to give an idea of
the different kind of topics that have been covered.
In section 4, transition from the GEDIS model to
Sports Service Area interface in control room is
evaluated. In this section, a set of recommendations
about graphical interface improvement are studied.
Finally, conclusions and future research lines.
2 GEDIS GUIDELINE
The previous research on human interface design
guidelines includes for example the standard ISO
11064 that establishes ergonomic principles for the
evaluation of control centers (ISO, 2004), the
Human Factors Design Standards HFDS of the
Federal Aviation Administration of the United States
(Federal Aviation Administration, 1996), the Human
Interface Design Review Guidelines NUREG 0700
in nuclear power plants (Nuclear Regulatory
Commission, 2002), the I-002 Safety and
Automation Systems NORSOK about Norwegian
petroleum industry (Norsok, 2006) and the Man
Systems Integration Standard NASA-STD-3000
about manned space programs (Nasa, 1995).
An example of cognitive modelling in human
computer interaction is the GOMS guideline, about
goals, operators, methods and selection rules in
usability analysis (Card et. al., 1983). In
combination with Keystroke-Level Model KLM an
interface can be studied, also task execution time
and human efficiency can be studied too.
The GEDIS guide is a method that seeks to cover
all the aspects of the interface design (Ponsa and
Díaz, 2007). From the initial point of view of
strategies for effective human-computer interaction
Figure 1: A typical cyclic network menu in supervisory
control interface associated to navigation indicator.
applied to supervision tasks in industrial control
room (Nimmo, 2004), (Schneiderman, 1997).
The GEDIS guide offers design
recommendations in the moment to create the
interface. Also, already offers recommendations of
improvement of interfaces created. The GEDIS
guide is composed of two parts: description of ten
indicators and measure of ten indicators. The
indicators have been defined from extracted
concepts of other generic human factors guidelines,
and for aspects of human interface design in human
computer interaction.
The method to continue for the use of the GEDIS
guide is: analyze the indicator, measure the
indicator, obtain the global evaluation index and
finally offer recommendations of improvement.
For the correct use of the GEDIS guide it is
necessary the collaboration between the control
room technical team and the human factor
technician, since in some cases to analyze the
indicator is necessary the expert’s opinion.
2.1 Indicators List
The GEDIS guide consists of ten indicators that seek
to cover all the aspects of the interface design in the
supervisory control domain. The indicators are:
architecture, distribution, navigation, color, text font,
status of the devices, process values, graphs and
tables, data-entry commands, and finally alarms. For
example, the relationship between architecture and
navigation indicators is illustrated in Fig. 1. The
physical plant can separate in area, subarea, and
team. In the same way, the interface presents four
navigation levels. Fig. 1 shows a possible layout to
locate all the connections between screens. The
connection among screens is complex in a
supervisory control interface. From the point of view
ICINCO 2007 - International Conference on Informatics in Control, Automation and Robotics
162
Figure 2: An example of object’s layout inside the screen
for the distribution indicator.
of human computer interaction, is a typical example
of cyclic network menu.
Distribution indicator of Fig. 2 shows a possible
layout to locate all the objects inside the screen. The
objects homogeneous distribution allows us to
maintain the interface coherence when user changes
the screen. The secondary objects are located in
screen areas that don’t require the user’s attention
(enterprise logo, and date/hour information). The
user should recognize the screen title and the general
navigation tool to move among screens. The main
objects are located in visible screen areas (alarms,
data-entry commands, subnavigation tool, and
synoptic objects). The user can surveillance the
process evolution without acting (human out of the
loop), or he can decide to introduce changes in the
set point or in the controller’s parameters (human in
the loop) inside a faceplate window in the data-entry
command object. The user should have special
attention to the alarm indicators, which should be
located in a clear way in the screen so that the user
can recognize the situation (situation awareness).
3 SAF PROJECT
This section presents the development of the
supervisory control system, with special emphasis
on the interface features, for the Sports Service Area
(SAF in Catalan version) of the Universitat
Autonoma of Barcelona (UAB). This supervisory
control system has been developed by a team of
Computer Sciences Engineers with common design
guidelines. Even some basic principles on
ergonomics and interface design were taken into
account; the GEDIS analysis will show existing
weakness. An alternative presentation of the SAF
project can be found in (Vilanova and Gomà, 2006).
Figure 3: Main window of the developed monitoring
system with a global view of the Sports Service Area.
Figure 4: ISA-PID used to close the loops.
First of all, it is worth to know that the UAB is a
campus based university with more than 40.000
inhabitants (students, academics, staff, etc.). In fact,
this makes the University campus to behave like a
city with some sort of facilities offered for their
inhabitants. Among them, the Sports Service Area
(SAF) is one of the largest and with more complex
installations. It encompasses indoor as well as
outdoor activities that run for more than 12h each
day. Just to give an idea of the different installations
that give support to the offered activities. We can
find there: covered swimming pool, boulders,
outdoor facilities for tennis, football, athletics, etc.,
indoor installations for fitness, basketball, aerobic,
gym, etc. (Antsaklis et. al., 1999), (Astrom, 1999),
(Kheir et. al., 1996).
Therefore, large complexes build up from
different subsystems. Each one of these subsystems
has to assure a quality of service each day. This fact
introduces the need for good monitoring tools to
help on this task. In addition, there is a hug number
APPLICATION OF A HUMAN FACTOR GUIDELINE TO SUPERVISORY CONTROL INTERFACE
IMPROVEMENT
163
of automation and control problems (automated
watering, temperature controls for water and indoor
areas, lightning systems, ozone controlled system for
water cleaning in covered swimming pools, etc.).
The SAF project has different automation levels:
from field instrumentation and data collection, PLC
programming and feedback loop configuration, to
information integration on a SCADA system. The
SAF project use PLC from different manufacturers
(SIEMENS, GE-FANUC, Landys, and Mitsubishi).
All the data has been integrated through
implementing the corresponding supervisory control
interface with Wonderware suite called In TOUCH.
The basic communications use specific drivers to
connect PLC with PC based control; the advanced
communications use the standard OPC protocol.
An example: for indoor activities temperature
control of both the SAF building and the water for
the gym showers has been implemented. This means
the students, in control room operator role, had to
close some loops by using the ISA-PID present
either in the PLC or in the software (see Fig. 4).
One important aspect of a monitoring system is
how it deals with alarms. As this feature is a
common feature, it should be incorporated in every
part of the system according to the same rules. This
way, in every SCADA window and alarm indicator
has to be included that shows the human operator if
an alarm is currently fired and can let you go
directly to the main alarm window to process it.
Finally, design implementation and configuration
of the In TOUCH based SCADA system has been
done starting from zero. This allowed to think of a
distributed application where from the different
computers located either at the main SAF office or at
the technical staff room the overall system can be
accessed. In addition a special access, using terminal
services, for the technical staff has been enabled so
remote operation can also be done from outside the
SAF installations.
4 SAF EVALUATION
The connection between SAF designer and GEDIS
guideline designer is necessary to define a global
evaluation of the SAF interface and can give a set of
recommendations about graphical screen
improvement (see Fig. 5).
Figure 5: SAF interface evalutation with GEDIS guide
method.
4.1 Evaluation
The evaluation expressed in quantitative numeric
form or in qualitative format it seeks to promote the
user's reflection that stuffs the GEDIS guide by way
of questionnaire, so that it picks up the use
experience that doesn't end up being verbalized in
many occasions.
Each one of the indicators of the Table 1 and
Table 2 can substructure in diverse subindicators.
For example, the indicator Color can be detailed in:
absence of non appropriate combinations (5),
number of colors (5), blink absence (no alarm
situation) (5), contrast screen versus graphical
objects (3), relationship with text (3). For each
subindicator it is recommended it is punctuated
numerically in a scale from 1 to 5. In this example
the number of subindicators of the indicator Color is
J = 5 (see formula 1). The formula necessary to
calculate the numeric value of each indicator is the
formula 1.
=
=
=
J
j
j
J
j
jj
w
Subindw
Indicator
1
1
(1)
where, Subind= subindicator and w = weight.
The mean value that one obtains by the formula
1 with these numeric values is 4,2 . If it is rounded,
the value is 4, so that to the indicator Color it is
assigned the value 4 in this example, considering
that each one of the subindicators has the same
weight (w1 = w2… =wJ = 1).
ICINCO 2007 - International Conference on Informatics in Control, Automation and Robotics
164
Table 1: GEDIS guide indicators (part one).
Indicator name and
Subindicator name
Numeric/qualitative range
and SAF numeric value
Architecture 1,7
Map existence [YES, NO] [5,0] 0
Number of levels le [le<4, le>4] [5,0] 0
Division: plant, area,
subarea, team
[a, m. na] [5,3,0] 5
Distribution 3
Model comparison [a, m. na] [5,3,0] 3
Flow process [clear, medium, no clear]
[5.3,0] 3
Density [a, m. na] [5,3,0] 3
Navigation 3
Relationship with
architecture
[a, m. na] [5,3,0] 3
Navig. between screens [a, m. na] [5,3,0] 3
Color 5
Absence of non
appropriate combinations
[YES, NO] [5,0] 5
Color number c [4<c<7, c>7] [5,0] 5
Blink absence (no alarm
situation)
[YES, NO] [5,0] 5
Contrast screen versus
graphical objects
[a, m. na] [5,3,0] 5
Relationship with text [a, m. na] [5,3,0] 5
Text font 3,2
Font number f [f<4, f>4] 5
Absence of small font
(smaller 8)
[YES, NO] [5,0] 0
Absence of non
appropriate combinations
[YES, NO] [5,0] 5
Abbreviation use [a, m. na] [5,3,0] 3
where, a= appropriate, m=medium and na = no
appropiate.
Each one of the indicators of the Table 1 is
measured in a scale from 1 to 5. The human expert
operator prepares in this point of concrete
information on the indicator, so that it can already
value the necessities of improvement. The values of
the indicators can group so that the GEDIS guide
offers the global evaluation of the interface and it
can be compared with others interfaces.
The formula necessary to calculate the GEDIS
guide global evalutation index is the formula 2.
=
=
=
10
1
10
1
_
i
i
i
ii
p
indp
evaluationGlobal
(2)
where, ind = indicator and p = weight.
Table 2: GEDIS guide indicators (part two).
Indicator name and
Subindicator name
Numeric/qualitative range
and SAF numeric value
Status of the devices 4
Uniform icons and
symbols
[a, m. na] [5,3,0] 3
Status team
representativeness
[YES, NO] [5,0] 5
Process values 3
Visibility [a, m. na] [5,3,0] 3
Location [a, m. na] [5,3,0] 3
Graphs and tables 4
Format [a, m. na] [5,3,0] 3
Visibility [a, m. na] [5,3,0] 3
Location [a, m. na] [5,3,0] 5
Grouping [a, m. na] [5,3,0] 5
Data-entry commands 3
Visibility [a, m. na] [5,3,0] 3
Usability [a, m. na] [5,3,0] 3
Feedback [a, m. na] [5,3,0] 3
Alarms 3,8
Visibility of alarm
window
[a, m. na] [5,3,0] 3
Location [a, m. na] [5,3,0] 3
Situation awareness [YES, NO] [5,0] 5
Alarms grouping [a, m. na] [5,3,0] 5
Information to the
operator
[a, m. na] [5,3,0] 3
where, a= appropriate, m=medium and na = no
appropiate.
In a first approach it has been considered the
mean value among indicators expressed in the
formula 2. That is to say, to each indicator it is
assigned an identical weight (p1 = p2… =p10 = 1)
although it will allow it in future studies to value the
importance of some indicators above others. The
global evaluation is expressed in a scale from 1 to 5.
Assisting to the complexity of the systems of
industrial supervision and the fact that an ineffective
interface design can cause human error, the global
evaluation of a supervision interface it should be
located in an initial value of 3-4 and with the aid of
GEDIS guide it is possible to propose measures of
improvement to come closer at the 5.
4.2 Experimental Study
The experimental study is the evaluation of SAF
interface with the collaboration of control
engineering students from Technical University of
Catalonia. From Vilanova i la Geltrú city, twenty
five students monitoring SAF interface around three
weeks. The students define a numeric value for each
indicator and propose interface improvement.
APPLICATION OF A HUMAN FACTOR GUIDELINE TO SUPERVISORY CONTROL INTERFACE
IMPROVEMENT
165
Figure 6: Original Piscina ACS screen.
Figure 7: Piscina ACS revisited with changes in color
indicator.
The SAF interface global evaluation is 3,4. The
global evaluation is expressed in a scale from 1 to 5,
so it is necessary to indicate SAF designer a set of
important recommendations:
revise the relationship between architecture,
distribution and navigation indicators
improve the feedback between interface and
human operator in data-entry commands
indicator
improve the location of alarm indicator
With GEDIS guide is possible too to indicate
SAF designer a set of important recommendations
about graphical screen improvement. For example,
the Piscina ACS screen can improve with a set of
changes in color and text font indicators. Fig. 6
shows the original Piscina ACS screen and Fig. 7
shows revisited Piscina ACS screen.
A second example, the Fronton and Rocodrom
screen can improve with a set of changes in
distribution indicator.
Figure 8: Original Fronto and Rocodrom screen.
Figure 9: Fronto and Rocodrom revisited with changes in
distribution indicator.
Fig. 8 shows the original Fronton and Rocodrom
screen and Fig. 9 shows revisited Fronton and
Rocodrom screen.
5 CONCLUSIONS
In tasks of human supervision in industrial control
room is habitual that an external engineer, - by
means of the commercial programs Supervisory
Control and Data Acquisition SCADA -, take charge
of designing the supervision interfaces in function to
the knowledge on the physical plant and the group of
physical-chemical processes contributed by the
process engineers.
Although standards exist about security in the
human machine systems that impact in aspects of
physical ergonomics, interface design by means of
rules of style, it is remarkable the absence of the
design of interactive systems centered in the user
where the engineering usability and the cognitive
ICINCO 2007 - International Conference on Informatics in Control, Automation and Robotics
166
ergonomics can contribute significant improvements
(Nielsen, 1993).
The GEDIS guide is an approach that tries to fill
a methodological hole that joins the efforts of the
systems engineering and the human factors for the
improvement of the effectiveness of the human-
machine system in industrial control room.
The application of the GEDIS guide to the study
of cases contributes among other details the measure
in form of indicators of aspects of interface design,
the recommendation of changes for the improvement
of the interface, and a global evaluation index that
allows to quantify the current state of the interface
regarding the future state after applying the correct
measures.
The studied case presented shows a Spanish
academic application, but with the same
characteristics of an industrial project. With the
GEDIS guide approach it’s possible to perceive
diverse anomalies and to propose improvements in
the interface design.
Another current study with the GEDIS guide is
the analysis of a sugar mill interface. The Sugar
Technology Center (CTA) in Spain has been
developed a training simulator to modeling and
simulating the production process and the human
operators’ supervisory tasks. The simulator
developed in this center is an example of full scale
simulator, a type of simulator that reproduces the
whole operating environment (Merino et. al., 2005).
This simulator emulates the control room of a sugar
mill. A series of object oriented modelling library
tools are used to create each part of the sugar mill:
diffusion, evaporation, purification, sugar room,
boilers, dryer, and liquor storage.
In these moments the 4all-L@b Usability
Laboratory of the Technical University of Catalonia
is analyzing the GEDIS guide to simplify the
number of indicators of the guide, to improve the
evaluation method, and to promote the use of the
guide inside the cycle of life of the software
engineering, in this case in the early phases of the
supervisory control interface design.
ACKNOWLEDGEMENTS
Participation of the second author is supported in
part by the Spanish CICYT program under contract
DPI2004-06393.
REFERENCES
Antsaklis, P., Basar, T., DeCarlo, R., McClamroch,N.H.,
Spong, M., Yurkovich, S., 1999. Report on the nsf/css
workshop on new directions in control engineering
education. IEEE Control Systems Magazine, (10), pp
53-58.
Astrom, K.J., 1999. Automatic control: the hidden
technology. P.M. Frank ed.. Advances in Control:
Highlights of ECC-99, pp. 1-28.
Cañas, J.J., 2004. Personas y máquinas. Editorial
Pirámide, Colección Psicología
Card, S., Moran, T.P., Newell, A., 1983. The psychology
of human computer interaction. Lawrence Erlbaum
Associates, Inc.
Federal Aviation Administration, 1996. Human factors
design guide for acquisition of commercial-off-the-
shelf subsystems, non-developmental items, and
developmental systems (DOT/FAA/CT-96/01). Atlantic
City International Airport, DOT/FAA Technical
Center
Granollers, T., Lorés, J., Cañas, J.J., 2005. Diseño de
sistemas interactivos centrados en el usuario. Editorial
UOC, Colección Informática, No 43
Holstom, C., 2000. Human factors and control centre
issues. What lessons we have learned. Institute for
Energy Tecnology, OECD Halden Reactor Project
ISO International Organization for Standarization, 2004.
Ergonomic design of control centres, parts I, II, III,
IV. In URL: http://www.iso.org
Kheir, N.A., Astrom, K.J., Auslander, D., Cheok, K.C.,
Franklin. G.F., Masten, M., Rabins, M., 1996. Control
systems engineering education. Automatica 32 (2), pp.
147-166.
Merino, A., Alves, R., Acebes. L.F., 2005. A training
Simulator fot the evaporation section of a beet sugar
production. European Simulation Multiconference,
ESM-05, Oporto, Portugal.
NASA, 1995. Man system integration standards. NASA-
STD-3000, In URL: http://msis.jsc.nasa.gov/
Nielsen, J., 1993. Usability engineering. Academic Press,
Boston.
Nimmo, I., 2004. Designing control rooms for humans.
Control Magazine
Norsok Standard, 2006. I-002 Safety automation system.
Norwegian Technology Centre Oscarsgt. 20, Postbox
7072 Majorstua N-0306 Oslo. In URL:
http://www.olf.no y http://trends.risoe.dk/detail-
organisation.php?id=52#corpus
Petersern, J., 2000. Knowledge based support for situation
assessment in human supervisory control. Ph.D.
Thesis. Department of Automation. Technical
University of Denmark.
Petersen, J., May, M., 2006. Scale transformations and
information presentation in supervisory control.
International Journal of Human-Computer Studies,
Vol 64, 5, May, pp. 405-419.
Ponsa,P., Díaz, M., 2007. Creation of an ergonomic
guideline for supervisory control interface design. 12
th International Conference on Human-Computer
APPLICATION OF A HUMAN FACTOR GUIDELINE TO SUPERVISORY CONTROL INTERFACE
IMPROVEMENT
167
Interaction. July, Beijing, P.R. China. In URL:
http://www.hcii2007.org
Samad, T., Weyrauch, W., 2000. Automation, control and
complexity. John Wiley and Sons
Schneiderman, B., 1997. Designing the user interface.
Strategies for effective human-computer interaction.
Addison-Wesley, third edition
U.S. Nuclear Regulatory Commission, 2002. NUREG-
0700, Human-system interface design review
guidelines. Office of Nuclear Regulatory Research,
Washington DC 20555-0001. In URL:
http://www.nrc.gov/reading-rm/doc-
collections/nuregs/staff/sr0700/nureg700.pdf
Vilanova, R., Gomà, A., 2006. A collaborative experience
to show how the University can play the industrial
role. 7
th
IFAC Symposium on Advances in Control
Education, June, Madrid, Spain. URL:
http:www.dia.uned/ace2006
ICINCO 2007 - International Conference on Informatics in Control, Automation and Robotics
168