TRAIN AUTOMATION AND CONTROL TECHNOLOGY –
ERTMS FROM USERS’ PERSPECTIVES
, S. Sharples
, J.R. Wilson
Human Factors Research Group, University of Nottingham, UK
Ergonomics Team, Network Rail, UK
CCD Human Factors, Copenhagen, Denmark
The European Train Control System (ETCS) as part of ERTMS
(European Rail Traffic Management System) is a new automation
and control system which has fairly recently been introduced into
the UK rail system. This paper briefly reviews some of the potential
human factors issues associated with driving with ERTMS, drawn
from previous literature and rail standards and also from familiari-
sation activities. It then summarises and discusses some of these
issues based on data collected from interviews with UK ERTMS
The European Train Control System (ETCS) as part of ERTMS (European Rail
Traffic Management System) is a new automation and control system which has
been introduced into the UK rail system fairly recently. ERTMS operates in dif-
ferent levels and when driving in level two all movement authorities for the train
are given via a planning area on a DMI (i.e. an in-cab digital display unit), and
drivers are no longer using lineside signals. Therefore, ERTMS drivers receive
their primary signaling information from inside, rather than outside the cab. Addi-
tionally, the ETCS provides speed profiles on the DMI, which the drivers must
follow or the system will apply the brakes. Prior to the system applying the brakes,
the system provides overspeed and warning alarms. Drivers are still required to
monitor their environment outside the cab in order to detect and report any events
or hazards, as well as monitoring parts of the infrastructure such as level cross-
ings. Further information about ERTMS can be found on the UNIFE website
UK train driving has been ‘heads up’ driving, where drivers are predominantly
looking for information outside the cab and using their route knowledge to make
decisions about speed and braking control. However, with the introduction of
ERTMS, it is proposed that the driving philosophy and culture in the UK will
change from ‘heads up’ to ‘heads up, heads down’ driving. Introducing ERTMS
has also required changes in driving rules and lineside signage, which are also
expected to influence long term driver route knowledge.
Train automation and control technology 169
Prior to the implementation of ERTMS in the UK, there was a considerable amount
of work discussing potential human factors issues with train driving under ERTMS.
However, there has been little actual research into the effects of ERTMS on train
driving in the UK since its implementation in 2009. Questions have been raised
about its effect on driving strategies and styles, and on performance.
These questions have been highlighted by the recent Rail Accident Investigation
Branch (RAIB) incident report (RAIB 2012) of the Llanbadarn automatic barrier
crossing incident in June 2011. The incident occurred on an ERTMS route where
a passenger train ran onto the level crossing when the crossing was raised and
the indicator close to the crossing was flashing red. The report implicated in-cab
signaling as one of several causal factors, and the driver reported that the he was
observing the DMI at the same time he should have been observing the lineside
indicator. One of the outcomes of the RAIB 2012 report was to recommend further
human factors work investigating driving with ERTMS.
This paper briefly reviews some of the potential human factors issues associated
with driving with ERTMS, drawn from both previous literature and rail standards
and also from familiarisation activities undertaken by the first author. Secondly,
it will summarise and discuss some of these issues based on data collected from
interviews with UK ERTMS drivers.
Potential human factors issues
The introduction of the ETCS has increased the level of automation in train driving.
Enhanced automation with ERTMS driving will ultimately change the role of the
driver. The driver’s role will consist of more monitoring tasks and anticipating
intervention in case of any disruptions (Stoop et al. 2008). Therefore the driver’s
role and tasks need to be reassessed and how this will in turn impact on drivers’
cognitive strategies and attention.
Supervisory control systems represent situations in which automation and humans
work togetherto accomplish a task (Sheridan 2002). The ETCS acts as a supervisory
automated braking system which instructs any changes in speed and braking points.
The use of automated subsystems means that the role of the driver shifts towards
supervisory control and there will be greater use of cognitive functions such as goal
monitoring, exception handling and recognising anomalies (Woods et al. 2010).
However, in supervisory control, misdirected attention could cause goal conflicts
to be missed or misprioritised (Woods et al. 2010) which could be a concern with
ERTMS driving. Also, it is unclear how the changes in the driver’s expertise and
automating the driver’s goal setting activity will affect driver control.