HUMAN FACTOR DESIGN IN UK DEFENCE
4. THE WALRUS LIFE EXTENSION CASE
4.1 THE PLATFORM
The Walrus Class consists of four diesel electric submarines with a crew of 50 persons, which sail with an unmanned engine room. It was ordered in 1978 and the first one was operational in 1990. The Human Factors aspects were addressed at that time by TNO. A full scale wooden mock-up of the command centre and the engine room was made to support evaluation of the lay-out of the rooms, the design of the workplaces and maintainability. To give an example of the impact of that work, it was found that there wasn’t enough space in the engine room for maintenance. As a result, the hull was lengthened on the drawing table shortly before it was built.
A Life Extension Program is planned to start in 2012, to guarantee this capacity at least until 2025. Because of the specific character of the Life Extension Program, the Program Manager has appealed to the Dutch Underwater Knowledge Centre (DUKC). DUKC is a working group supported by the Netherlands Defence Manufacturers Association (NIDV), aiming at maintaining this specific domain knowledge. Within DUKC, a partnership was initiated that offered to support a conceptual study on engineering work. In this partnership, TNO Human Factors had the following responsibilities: the design of the physical lay-out of the command centre and individual work stations, and new interface concepts for the new combat management system Guardion. The project was awarded and started mid 2009, under the name WESP (Walrus Engineering Support Project).
Other essential WESP consortium partners were IMTECH, NEVESBU, TECNOVIA and NEDINSCO.
Again a Human Factors Engineering (HFE) Team was formed consisting of Human Factors experts of TNO and defence functionaries (equipment specialists, representatives of the future users, CMS specialists, and platform maintainers). Other subject matter experts were invited only occasionally, when needed. In the next subsections, we will describe how we approached this project with this team, following the framework of section 2.
4.2 FUNCTIONAL LEVEL
Initially, it was expected that the Life Extension Program would have minimum impact on the command centre since there is hardly space to make important changes.
Only an ergonomic improvement of the workstations was demanded. However, the Program Manager encouraged the HFE Team to make an analysis of the consequences of a changing operational context and the system adaptations for the way of working in the operations room. When a new CONOPS is needed, new requirements for the physical space would probably arise as well.
In three design workshops, the Human Factors Engineering Team handled the functional level. An
important change of operational context was already identified in earlier studies by the RNLN, DMO and TNO: due to the end of the Cold War, the submarines need to operate less often in deep waters, but more often in shallow waters, and they will work less often in isolation, but more often within a NEC environment. We continued our analysis with defining ten scenarios covering the new situation (Transit, Periscope depth, Deep underwater, etc.), and with identifying the major functions (see fig. 7).
4.3 CONCEPTUAL LEVEL
Again in three design workshops, the HFE Team went through the conceptual phase. In the first design work shop, we started with mapping out the new systems requirements and the new operational concept. The Life Extension Program provides an opportunity to replace the current, almost outdated, Combat Management System by Guardion, a CMS developed by DMO’s own software house CAMS Force Vision (Centre for Automation of Mission Critical Systems). Guardion enables better integration, better man-machine interaction, and better flexibility. But also the new operational context requires important system adaptations. The main ones are:
• The introduction of a non-hull penetrating optical electronic mast, which makes the outside picture available for potentially all operators, in stead of the PWO or CO who only using a periscope.
• The introduction of a Warship Electronic Chart Display, replacing the paper navigation charts. Among other things, WECDIS facilitates travel planning and changes the task of the officer from active navigation into monitoring.
• The introduction of SATCOM, to improve communication within a task group and NEC organization. It is expected that the crew needs to process much more information.
In the next workshop, the set of operators was established and a link analysis was carried out for all ten scenarios, taking the new systems into mind. This resulted in a graphical representation of the CONOPS.
Fig. 8 shows this graphical representation for the periscope depth scenario. It shows the relation between the operators, where thicker lines indicate stronger relationships.
In the third design workshop, these graphically represented CONOPS were used to sketch by the Human Factors Engineering Team three alternatives for the new layout. The principles for the three differed widely, to clarify the essential requirements and wishes for the final draft.
Maneuver Weapon deployment
Navigation Command
Sensor deployment
Picture
compilation Platform
Periscoop diepte, Complexe aanval
WN WOP
ACCO
SOP2 STL SOP1 EOV CDT
OPTROP
?
SRSOP SREOV
PtP voice Zicht op Dichtbij / Overleg Middelen delen
R Eindverantwoordelijke R Incidenteel
EO
Sensor Deployment
Navigation Picture Compilation
Command
WC AC Weapon Deployment
RG DOF
SC PROP
Maneuver
Figure 8: Upper figure, the identified maritime tasks.
Lower figure, a graphical representation of the concept of operation for the scenario “Periscope Depth” (in Dutch).
The thickness of the lines connecting operators represents the strength of the relationship.
The starting point for the first alternative, the conventional concept, was to minimize changes to the existing layout.
The starting point for the second alternative, the revolutionary concept, was to release as much as possible all current requirements, even the dimensions of space. The design of this alternative was not so much an end in itself but a means for thinking “out-of-the-hull”, so to come to an idealistic command center.
The motto for the third alternative, the evolutionary concept, was to make a realistic, qualitative improvement compared to the conventional design, inspired by the revolutionary design.
The conceptual phase was concluded with a separate evaluation session. The first and the third alternative were evaluated by independent user experts, and their technical and financial feasibility were assessed by other subject matter experts, including all partners of the WESP consortium. As for the conventional design proposal, it was assessed as a good step forward for the
individual operator to achieve with limited additional costs, risks and time. Regarding the evolutionary design proposal, it is optimally designed for the new CONOPS and it is a good step forward compared to the conventional design proposal. However, the costs are higher, and the risks and renovation time are increased. It was estimates that the additional costs are advantageous compared to the obtained operational and functional value. Budgetary constraints and the acceptance level of risk led the Program Manager to choose for a combination of both. This is worked out next.
4.4 DETAILED LEVEL
At the detailed level, again three design workshops with the Human Factors Engineering Team were carried out.
One workshop was focusing on the layout of the operations room. For optimal team performance, shared situation awareness was supported by introducing overview screens, and direct communication was supported by strongly considering the lines of sight during positioning the individual operators. Another design workshop was focused on detailing the individual workstations. Much effort was put in ergonomics. This was a hard job, since there was hardly space to do it right.
A particular constraint was an existing shock frame in which the new workstations had to be replaced. In fig. 9, you can still sea some ribbons of the shock frame.
Further, the workstations are designed in a way that neighboring screens can easily be looked at and operators can share their work between neighbors. They are also able to take over monitoring tasks under certain circumstances and as a consequence, they can scale down and up easily, allowing staff to relax whenever possible.
In a third workshop, special aspects were designed, such as a WECDIS workstation and a workstation for the Commanding Officer. In addition, during all three workshops, attention has been paid to designing the new work environment in such a way that more space is experienced and less discomfort.
4.5 IMPACT
The Submarine Life Extension Program doesn’t have a crew reduction target. It is known, however, that submarine personnel have a lower retention compared to personnel of other platforms. Lower retention leads to higher training costs and even a danger of under-staffing, at the expense of the deployability of platforms. This more comfortable work environment contributes to higher retention. Further, the layout is optimally suited for the new CONOPS, which is advantageous for reducing overhead. Besides the ergonomic design of high quality work placements, which eases individual workload, effort is also spent on enabling an adaptable manning due to the scalability aspect. The new layout has been subjectively evaluated as well on aspects such as efficiency, collaboration, review, flexible deployment, comfort and endurance, and was rated significantly higher than the current lay-out (on average, 8.0 vs. 6.6).
Figure 9: Impressions of the new operations room.
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Figure 10: During an evaluation session, the design is systematically assessed by independent subject matter experts. The stereoscopic presentation immerses the users and decision makers in the future environment.