Automation Challenges of Socio-technical Systems

8 The Impact of Human Stability on Human–Machine Systems: the Case of the Rail Transport

8.1. Introduction

The reliability of automated systems has been an essential constraint for researchers since the emergence of automation. Human–machine systems (HMS) are automated systems with the particularity of having one or more human operators in the loop. One of the key roles of the operator is to increase the resilience of the technological processes and the human–machine system in general, by relying on their (human) adaptability and improvisation. Resilience [HOL 06] is the ability of the system to contain and to adapt to the consequences of unforeseen and unpredictable situations, be them simple or catastrophic failures. The concept of resilience differs from the well-known concept of robustness, which is the ability of the system to work under different operating conditions, including failures that can a priori be foreseen. Therefore, resilience has an important impact on the risk management of human–machine systems.

Transport systems are an important type of human–machine systems, and the incidents and accidents related to this type of systems are a highly sensitive issue. Using technological progress, the risk of accidents caused by technical factors is twice smaller than the risk of accidents involving the human factor [COT 07]. Therefore, it is clear that in order to improve the resilience of rail transport systems, it is necessary to focus on the human factor from the ...