The increasingly advanced automation systems controlling modern sea
vessels has led to more complex user interfaces. A typical operator must
interact with many different systems, often with different interface
styles, during an operation. Complex and multiple interfaces can cause
cognitive overload if the operator is presented with excess information.
The operator can also be physically affected if the equipment is poorly
placed. Depending on the ship owner, the ship yard and the suppliers of
equipment, the composition of the equipment in the operator station can
vary considerably and is often ergonomically sub-optimal.
Human
machine interface (HMI) work has a long history in maritime settings but
is often given low priority due to perceived increased development time
and economic pressures. The economic aspects play an important role in a
vessel’s lifecycle and issues concerning HMI and usability are, in many
cases, not a part of the discussion until late in the cycle when it is
too late and expensive to make vital changes to implement an optimal
solution. An overall increased mental load when operating a system is
tiring and leaves less mental capacity to handle safety-critical events.
Poorly fitted equipment combined with low usability causes a long term
problem for the operators.
The overall aim of maritime HMI and
human factors (HF) research is to lower the operator’s cognitive load
and make the workflow more efficient. Over the last 10 years,
Rolls-Royce Marine has been engaged in a rapid process of development of
both systems and devices that are vital on today’s vessels. For
Rolls-Royce, the next step of developing the future systems included
ensuring a good HMI environment onboard to support the complexity of
offshore operations today.
In perspective
Traditional
ship bridges are often cluttered with equipment, buttons and levers.
The placement depends on who arrived first to install their equipment at
the ship yard. With no holistic focus on where to place equipment, it
is either just randomly placed somewhere in the consoles or placed
according to the wish of the captain on duty that day. When asked, the
crew often reply that they have concerns but that they are ‘silly
details’ or ‘luxury problems’. However, it soon becomes clear that while
the individual problems might be small, there are usually many of them
and as they start to pile up they add unnecessarily to the operator’s
mental workload.
When taking all the silly details and luxury
problems into account it was possible to create a ship bridge concept
that will improve operational safety and comfort on board during
demanding offshore operations. The work on achieving this aim commenced
late Autumn 2010.
Redesigning the ship bridge environment
The
process of doing a complete redesign of the ship bridge environment,
including consoles, levers and software interfaces, was done by
incorporating human factors, ergonomics and usability as the basic
foundation for developing a user centred design process. The user
experience is a vital element and by including it, it was possible to
introduce a more comfortable, clutter-free and safe working environment.
Four
design principles were implemented where simplicity, performance,
safety and proximity were the key elements. To fulfil these goals there
was emphasis on: good ergonomics; variation of work position; proximity
to touch interfaces and levers; flexibility to support operational
preference; an improved view of the aft deck to support a safer
operation.
The data needed to build a base of knowledge for the
first concept sketches were collected and interviews with operators and
visits on several different types of vessels were carried out. To
actually understand the work environment and gain insight in life at
sea, the gaps were filled by going on board to observe a range of real
life platform supply operations in the North Sea. The knowledge gained
was used to perform testing in a simulated virtual environment.
Throughout
the concept development phase, realistic simulations in a virtual
environment were carried out to collect data in Rolls-Royce’s Training
and Technology Centre in Aalesund, Norway. The data collected using
advanced eye-tracking equipment was used to identify the periods of time
when the operation was at its most safety-critical. These periods were
known as safety-critical focal points. With this knowledge it was
possible to redesign the vessel’s bridge environment to better support
the users during standard work procedures and when reaching the critical
point of operation. By obtaining knowledge about the operators’ eye
scanning patterns during all stages of the operation, placement of
monitors, levers and console designs could be adapted to give the best
possible support to the operator, with the aim of reducing the human
error rate.
The results of the research were fed directly into the
concept development phase of the bridge consoles. Functional analyses
were carried out to investigate operator interaction with equipment and
action was taken to remove ship bridge clutter. Which functions were
vital, which could be removed or merged? In parallel, several different
prototype iterations of bridge consoles were carried out, from cardboard
and Post-Its, to polystyrene and in the end a full-scale plastic model
released at the Nor-Shipping convention in Oslo in May 2011.
Ship bridge clutter and comfort
Ship
bridge clutter appears when equipment from several different suppliers,
with different interfaces and interaction styles, gathers in the bridge
consoles. The results from the experiments introduced possible
improvements from the current, more cluttered, aft bridge setup
traditionally used, to the new Rolls-Royce Unified Bridge setup. The
following changes were introduced:
- The armrests were moved from the operator chairs to the consoles, increasing distance/angle from torso to elbow.
- There was a supported seated and standing work position.
- The surfaces were cleared of equipment by integrating third party
equipment into an auxiliary system controlled using a touch panel.
- All controllers - levers, button panels and monitors - were moved closer to the user.
These
changes made it possible to reduce the amount of necessary monitors and
open up the field of vision to the aft deck. This reduces visual
scanning of the aft bridge and aft deck environment and means there is a
smaller area over which to maintain situational awareness, which can
have an impact on the operator’s workload during operation and critical
phases.
Ergonomically-designed chairs were installed with a
leather/alcantara combination that increased the friction and reduced
dampness when seated. Situation awareness was increased by implementing a
common alert philosophy where all bridge alerts could be silenced and
handled from one panel, so that the operator does not have to search for
the correct alert to silence. Environmental visibility and reduced
reflections, both in console design/colour and graphical user
interfaces, contributed to maintaining the operator’s night vision. A
common dimming philosophy was also implemented so that all equipment
could be dimmed from one place. With this unified interaction concept,
the operators have more equipment within arm’s reach than in traditional
bridge consoles.
Levers and emergency switches
The
goal concerning levers and emergency switches was to simplify and
prevent error. Previous experiences had shown that operators were likely
to make mistakes as it was difficult to figure out which emergency
switch belonged to what function. Placing them in easily recognisable
positions would rule out the need for extra reminders. The vessel’s
control levers were also given a makeover. Fresh designs, developed
through a user-centred design process, gave levers that supported safe
operation through grip, indications and easy access to functionality.
The motorised levers give tactile feedback to the user and were
ergonomically tested using well-known methods, such as Rapid Upper Limb
Assessment, with excellent scores. Reduction of footprint in consoles
was also important as in many cases two levers or more were combined
into one.
A unified expression
The
graphical user interfaces (GUI) on maritime applications are often the
only way the operator can interact with the equipment. Careful placing
of information and an easily recognisable way of navigating reduces the
risk of operators becoming confused.
GUI was given a great deal of
attention during the development of the Rolls-Royce Unified Bridge and a
complete redesign of all Rolls-Royce applications was carried out. The
Rolls-Royce Common Look and Feel (CLF) initiative was put in place to
constitute a common platform for Rolls-Royce Marine software, across
applications and screen sizes.
The goal has been to define
guidelines for the graphical user interface, as well as principles for
interaction and usability. A CLF style guide has been developed. It is a
dynamic document continually edited and updated based on feedback from
the various application teams and the end users. Redesigning the
applications has resulted in consistent interfaces with a common way of
navigating across systems, a common alarm philosophy and a common way of
switching between systems, giving the user full overview and control.
From concept to product
The
work of collecting user feedback based on the plastic prototype was
important and the initial prototype consoles have been improved based on
feedback. The front end of the consoles have been angled, so that the
operator can have a better work position during operation.
The
wrist is kept in a relaxed and straight position while the hand operates
the lever. This is an important improvement to the operators,
especially for winch/anchor handling operations which demands hours of
static muscular activity, as there is no possibility of releasing the
levers to run it in automatic mode. The consoles have been
industrialised and are of a modular type so that the different modules
can be combined to suit several different types of vessels.
The
first installation of the Rolls-Royce Unified Bridge left port in August
2014 on board the platform supply vessel Stril Luna owned by Simon
Møkster Shipping. The operators were equipped with user experience
assessment folders, so the Rolls-Royce Unified Bridge can develop and
improve in favour of the operators in the future.
By Frøy Birte Bjørneseth of Rolls-Royce Marine.
This article first appeared in issue 532 of The Ergonomist, October 2014.
Back