Contemporary Ergonomics and Human Factors 2013

TRAIN AUTOMATION AND CONTROL TECHNOLOGY –

ERTMS FROM USERS’ PERSPECTIVES

A. Buksh

1,2

, S. Sharples

1

, J.R. Wilson

1,2

,

G. Morrisroe

3

&B.Ryan

1

1

Human Factors Research Group, University of Nottingham, UK

2

Ergonomics Team, Network Rail, UK

3

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

drivers.

Introduction

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

(www.ertms-online.com).

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.

http://dx.doi.org/10.1201/b13826-40

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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

Automation

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

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.