Keskusteluihin perustuva suurkuvakonseptin luonnos

Minkälainen suurkuvakonsepti työpajojen keskustelujen pohjalta voidaan laatia?

Ensinnäkin suurkuvien rooli, käyttötapa ja sisältö riippuvat laitoksen tilasta:

valvomon suurkuvanäytöillä on esitettävä erilaista tietoa esimerkiksi normaaliteho-ajon aikana kuin vuosihuollon yhteydessä. Lisäksi suurkuvanäytöillä on ainakin neljä keskeistä funktiota: ne välittävät yleiskuvan laitoksen tilasta sekä tukevat tilannetietoisuutta, muutoksen nopeaa havaitsemista, yhteistyötä ja toimintojen koordinointia.

Osallistujien enemmistön mukaan on toivottavaa, että suurkuvanäyttöjen hal-lintaa koskeva vastuu on jaettu. Lisäksi toivottiin, että näyttöjen sisältöjen suun-nittelua koskevaa vastuuta jaettaisiin useille henkilöille ja että operaattorien edustajat pääsisivät osallistumaan sisältöjen suunnitteluun. Osallistujat eivät pitäneet näyttöjen interaktiivisuutta erityisen keskeisenä piirteenä, ja heidän mielestään operaattoreilla ei ole aikaa leikkiä näytöillä. Paras ratkaisu olisikin, jos suurkuvanäyttöjen sisältö vaihtuisi automaattisesti, jotta näyttöjen hallintaan kuluisi mahdollisimman vähän aikaa.

Toivottavaa olisi, että suurkuvanäytöt olisivat hyvin integroituneet laitoksen eri tietojärjestelmiin. Osallistujat olivat kuitenkin tietoisia tähän liittyvistä tieto-turva- ym. ongelmista. Heidän mukaansa ei ole mitään syytä, miksi useamman operaattorin pitäisi kyetä samanaikaisesti ohjaamaan samaa suurkuvannäyttöä.

Sen sijaan yhteistoiminnan kannalta koettiin tärkeäksi, että suurkuvanäytöillä näkyisi, mitä muut ovat parhaillaan tekemässä.

Keskustelujen perusteella operaattoreilla on erilaisia toiveita tiedon abstraktio-tason suhteen. Toisaalta toivottiin, että suurkuvanäytöillä esitettäisiin mahdolli-simman yksityiskohtaista tietoa (”niin kuin paneeleilla”); toisaalta toivottiin, että niillä esitettäisiin pitkälle jalostettua tietoa laitoksen keskeisistä parametreista.

Myöskään siitä, kuinka kattavasti suurkuvanäytöillä olisi esitettävä tietoa laitoksen eri järjestelmistä, ei työpajojen keskusteluissa muodostunut yhtä selkeää kantaa.

Toisaalta operaattorit haluavat tietoa mahdollisimman kattavasti laitoksen eri järjestelmistä, mutta toisaalta he haluavat, että keskityttäisiin olennaiseen.

Osallistujat toivoivat, että suurkuvanäytöillä (ja erityisesti ns. yleiskuvanäy-töillä) esitettäisiin PI-kaavioon pohjautuva kuvaus laitoksen järjestelmistä, johon olisi ikään kuin upotettu eri osajärjestelmiä koskevaa ei-rakenteellista tietoa (esim. trendikäyriä). Operaattorit siis tarvitsevat sekä rakenteellista että ei-rakenteellista tietoa: tietoa sekä prosessin dynamiikasta yleensä että laitoksen yksittäisten järjestelmien tiloista. Yleisenä toiveena oli, että tieto olisi dynaamista ja ajan tasalla olevaa. Toisaalta on myös tärkeää, että kuvissa on staattista (ei-rakenteellista) tietoa, joka auttaa kuvan jäsentämisessä.

Tietyn suurkuvanäytön sisältö voi olla suunnattu yhdelle tai useammalle käyt-täjälle sen funktiosta riippuen. Esimerkiksi ns. yleisnäyttöjen kuvat on tarkoitettu kaikkien operaattorien käyttöön. ReM:llä ja TrT:llä voi kuitenkin olla myös omia näyttöjä, joiden sisällöt on suunniteltu vain heitä varten. Selkeä toive oli, että suurkuvanäyttöjen sisällöt suunniteltaisiin huolella ja että kuvat muokattai-siin suurkuvanäytöille sopiviksi. Suurkuvanäyttöjen suunnittelun tulisi perustua pitkälti muiden näyttöjen suunnittelussa hyviksi havaittuihin periaatteisiin.

4. Suurkuvanäytöt ydinvoimalaitosten valvomoissa – suunnittelutyöpajojen tulokset

Osa III:

Uudet näyttökonseptit

5. Evaluation of the Loviisa IRD-pilot

5. Evaluation of the Loviisa IRD-pilot

Jari Laarni, Hanna Koskinen, Leena Salo and Leena Norros

This chapter presents the results of the evaluation of the Fortum IRD pilot which is the first application of the IRD concept to the design of displays for the operation of the nuclear power process. VTT researchers have observed the design process of the Fortum pilot displays at design workshops and interviewed designers of the displays; they have also carried out a usability test of the Fortum pilot, and gathered information about user experiences; and finally they have carried out a heuristic evaluation of the Fortum pilot displays by themselves. The results suggest that the Fortum IRD pilot displays have shown to be applicable to the detection, identification and diagnosing of failure states in the nuclear power process. Considering the rapidity and spontaneity of the design process it is a respectable achievement. The displays have many useful features such as the presentation of history information through trend graphs, the use of Gestalt grouping principles in element clustering and the information richness of graphs.

These features make the displays nice looking and can also help operators in the identification and diagnosing of failures if they have enough time to practise the use of the displays. On the other hand, the displays have also several features that make them poorly suited to their purpose. For example, the Fortum IRD pilot is designed mainly for one plant state, the 100 % power level, but according to user comments, an overview display should be usable also in other plant states. Secondly, although trend information was considered very useful, the usefulness of trend normalisation was doubted. Also, the overuse of the colour grey, the lack of exact numeric parameter values and component labels, and the misplacement of some components hindered detection. Our claim is that these problems are caused by the fact that the final prototype is some kind of a hybrid of IRD displays and traditional displays based on process and instrumentation diagrams (P&I). We, therefore, see that, in the continuation of the development of large screen displays for Loviisa NPP two roads are open:

One possibility is to continue to develop this kind of a hybrid version which is a combination of traditional Loviisa overview displays and IRD displays. Another possible way to continue is to develop a genuine small-scaled IRD display for early detection of failures and develop a set of overview displays that are based on

existing Loviisa overview displays and whose structure is based on plant mimics.

We are convinced that the second alternative is the most promising to pursue.

5.1 Introduction

5.1.1 Background

Large screen displays (LSDs) play an important role in digital control rooms (CRs) based on desktop-based workstations in the presentation of the essential information of the system. It has been suggested that they could solve some of the main problems caused by digital technology.

Overall, it is supposed that LSDs can support decision making by providing an overview of the state of the process, provide information of important process changes, disturbances and alarms in a way that is easy to detect and identify, help users rapidly move to the place where the essential information is located and support co-operation and collaboration between operators by providing information of what other users are doing (Laarni et al., 2008). By providing an overview of the state of the system they can help users to develop a better mental model of the process. It is said that by this way the LSDs can improve situation awareness both at the individual and at the team level. They can also improve communication and coordination of activities. By means of LSDs users should be able to see how their own actions affect plant parameters that other users are operating. Correspondingly, the LSDs can show them how others’ actions affect those plant parameters they themselves are operating. The LSDs may help users to locate themselves in the information space and tell them by which way they can move from one display page to another. Since more information can be presented at the same time on a large screen, there is less need to scroll the display, open new windows or change the display content. By this way the LSDs should help to reduce the load caused by the secondary tasks.

On the other hand, the design of LSDs for the CR environment is challenging:

For example, since they are qualitatively different from desktop-based workstations, user-interface metaphors developed for small displays are not necessarily adequate in the design of LSDs (Laarni et al., 2008). Integration and consistency with desktop displays is also a challenging issue.

5.1.2 Key design features of the IRD concept

Since LSDs are qualitatively different from other kind of displays, new types of interface metaphors and display concepts – such as Ecological Interface Design (EID) or Function-Oriented Design (FOD) concept – are needed. These concepts are, however, not specifically aimed to the design of LSDs for process industry.

Rapid, easy and accurate detection of changes and failures can be improved, for example, by developing new types of displays that emphasize the essential information by making it more salient and deemphasize the less relevant information by reducing its visibility. Displays based on the Information Rich Design (IRD) concept have been developed by IFE (Institutt for energiteknikk) for those purposes for offshore production facilities (Braseth et al., 2003; Veland

& Eikås, 2007).

The Fortum IRD pilot is the first application of the IRD concept to the design of displays for the monitoring of the nuclear power process. According to the style guide of the Fortum pilot, “the concept refers to data displays that combine the Dull Screen colour principle with analogue coding, integrated trends and layout techniques to obtain high data density without causing information overload” (Braseth et al., 2003, p. 2). Key design principles in their development have been that the visual structure must be simple enough to allow easy scanning, orientation and reading of data-dense displays, and the layout should also provide a sufficiently correct picture of the plant system topology (Braseth et al., 2003; Veland & Eikås, 2007). It is also important that displays can be read by using different strategies depending on the user’s preferences and interests:

they should be useful all along the continuum from a brief glance to a close inspection.

Some of the central aims in the development of IRD displays have been to provide overview information, support early detection of failures and disturbances and help operators to diagnose the problem and stabilize the process. According to Veland and Eikås (2007), IRD displays should reduce working memory demands of operators by providing immediate visual access to frequently used data. By this way they could support the development of an acceptable level of situation awareness based on an overall view of the plant performance. They could also support collaboration and operation and co-ordination of activities within a crew.

The IRD concept is based on such design principles as display normalization, Dull Screen principle and information richness. General requirements for the IRD displays are shown in Table 9. The aim of display normalization is to help users to automatically detect deviations. Two types of normalized symbols have been developed, mini trends and normalized bar-like symbols without mini trends (Figure 19). They support rapid visual scanning of the data by adjusting the mapping between a physical measurement scale and an actual display scale for each data point. As a result, a set of graphs can be grouped together in such a way that small deviations can be immediately detected.

Table 9. General requirements for the IRD displays (Braseth et al., 2004).

1 Avoiding the keyhole effect by aiming for high information density.

2 Providing a wide variety of reading strategies for different tasks.

3 Providing a clear mapping between importance and visual salience.

4 Making the exact value of each data point available.

5 Providing means for simple visual comparisons between different data sets.

6 Supporting pattern recognition by providing means to identify patterns.

7 In the data set as distinct and recognizable.

Figure 19. Normalized trends and bar graphs indicating temperature, pressure, flow, and level (Braseth, 2008).

The aim of the Dull Screen principle is to make the display clearer and prevent visual noise by using specific colouring rules (Van Laar, 2001; Van Laar & Deshe, 2002). According to the principle, essential information is emphasized and less essential information is suppressed. Flicker is not used for alarm purposes, but, instead of that, alarms are indicated by highly saturated colours (red or yellow).

In general, dynamic information is shown by using salient fonts and colours, and information that is less important is presented by low-saturated colours.

IRD displays are dense with information – that is, a lot of information is presented on a small display area. A good example is the presentation of accurate valve position with a special panel in which a lot of information is presented in a small space (Figure 20). Different symbols are used for flow, level, pressure and temperature. The controller output is presented by a vertical bar outside the graph area. The expected position is presented by a diamond and the actual position by a black rectangle.

5.1.3 The starting point for the development of the Fortum IRD pilot As said, displays based on the IRD concept were originally developed for Norwegian offshore petroleum facilities. Some of the IRD displays were presented at HAMBO Group meetings in which they raised interest among the representatives of the group. The HAMBO large screen display project was planned in September 2006, and after that the development of overview displays that are based on the IRD concept were suggested to be included in the HAMBO reference group program. The idea was to study the applicability of displays based on the IRD concept as overall displays in the monitoring of the power process. The main aim was to investigate to what degree they can support the development of an accurate overall picture of the state of the power process and the acquisition of an accurate level of situation awareness (Rinttilä, 2007).

Fortum’s interest in the project is mainly based on the need to replace the old panels and desks project with large-screen overview displays during the Loviisa automation renewal project.

Figure 20. A normalized trend including information of valve position (Braseth, 2008).

Nuclear power companies both from Sweden (Ringhals, Oskarshamn and Forsmark) and Finland (Fortum and TVO) participate in the project. Three prototypes were planned to be developed, one of them at the Fortum development simulator. The other two prototypes have been planned to be designed for Ringhals (units 3 and 4) and for Halden Reactor Group’s (HRP) Hambo simulator. During 2007 it was planned that VTT could participate in the evaluation of the Fortum pilot within the frame of the SAFIR/O’PRACTICE project.

5.1.4 Research method

In the following the results of four types of research activities are presented.

First, we VTT researchers have interviewed designers of the displays, and secondly, observed the design process of the Fortum pilot displays at design workshops. The results of these parts are presented in Sections 5.2 and 5.3.

Thirdly, we have carried out a usability test of the Fortum IRD pilot, and gathered information about users’ experiences and conceptions. The results of

this study are presented under the title “Usability test of the Fortum pilot” in section 5.4. Lastly, we have carried out a heuristic evaluation of the Fortum IRD pilot displays by ourselves. The results of this evaluation are presented under the title “Heuristic evaluation of the Fortum pilot” in section 5.5.

5.2 Interviews of the designers

VTT researchers have interviewed the designers of the Fortum pilot and observed the testing of the pilot in order to get an idea of the rationale behind the design of the displays. Five designers of the Fortum pilot (two persons from IFE and three persons from Fortum) were interviewed in two occasions. The first interview session was arranged in 23^rd January 2008 at the KESI development simulator, and the second one was arranged in 30^th January at VTT. In the first session, two designers from IFE and one designer from Fortum were interviewed at KESI; in the second session three designers from Fortum were interviewed at VTT.

5.2.1 Interview of the IFE designers

Two designers from IFE and one designer from Fortum were interviewed at the Fortum development simulator (KESI) in 23^rd January 2008. The interview session lasted for about two hours. Several topics were tackled during the session. Most of them were related to the development of the IRD concept and the Fortum IRD pilot and to the advantages and disadvantages of their main characteristics.

5.2.1.1 Development of the IRD concept

The interviewed IFE designers told that at the beginning there were three designers that started the development of the concept. These designers are also the owners of the concept, and they have protected the concept with a US patent. The interviewees emphasized that the IRD concept was not originally developed for the nuclear industry, but for the off-shore petroleum community, since the oil companies searched for a different approach to the standard PI-diagram type displays.

In 2000 the design team started to develop IRD-type displays for workstation screens, that is, the first demonstrator was not a LSD. The first displays were developed so that the process can be operated directly by using these displays.

The IFE designers thought that by one IRD display they could replace ten ordinary displays so that the overview displays was not necessary at all. But people in the oil industry were not interested in the operator displays but thought that a better solution than to design a couple of operator displays is to design one large screen display. The aim is that the IRD displays will provide all the essential information to the operators. The IRD display will, thus, be a stable frame of reference which will not be used as an operator display.

The IRD concept is basically based on the work of Edward Tufte and Jens Rasmussen. Edward Tufte is famous for his work on visual design, and Jens Rasmussen has been one of the developers of the Ecological Interface Design approach. According to the IFE designers, the IRD displays are not based on detailed functional analysis of the target system, and therefore, when they developed the IRD displays, they did not carry out an abstraction hierarchy type of breakdown of the target system, but started from the analysis of existing LSDs. In fact, the designers’ main aim has been to develop a new type of presentation for the variables that are presented on the existing LSDs.

The main difference between IRD displays and ecological displays is that the aim of ecological displays is to aggregate information to a greater extent than IRD-type of displays. That is, the IRD displays present single-variable type information which is not aggregated in the actual display, whereas the EID displays present a lot of aggregated information from different variables, for example, about in-flow vs. outflow from control valves.

Traditional displays provide operators a cue when reaching a limit or an alarm status, whereas IRD displays are designed for detection of failures at the very early phase. The hope is that operators could detect the deviation before the alarm is triggered, since it is easier to look at a problem when the alarm state is not yet reached.

The designers told that in the oil industry the reception of IRD displays has been very positive. After the first prototype was presented in a conference, the oil companies asked whether IFE could make this type of display for them.

Since then seven or eight installations have been done for offshore petroleum community. According to the IFE designers the IRD concept is becoming some kind of standard in the oil industry. One reason for the rapid progress is the fact that in the oil industry the requirements of testing and approval are not as strict as in the nuclear field.

The designers, thus, claim that in the development of the IRD concept the oil

The designers, thus, claim that in the development of the IRD concept the oil

In document Tilannetietoisuutta tukevat näytöt prosessiteollisuuden valvomoissa (sivua 107-0)