Célia Martinie

Automation enables systems to execute some functions without outside control and to adapt functions they execute to new contexts and goals. Systems with automation are used more and more to help humans in everyday tasks with, for example, the dishwasher. Systems with automation are also used to help humans in their professional life. For example, in the field of aeronautics, automation has gradually reduced the number from 4 pilots to 2 pilots. Automation was first considered as a way to increase performance and reduce effort by migrating tasks previously allocated to humans to systems. This, in the hypothesis that systems would be better than humans would at performing certain tasks and vice-versa. Paul Fitts proposed MABA-MABA (Machine Are Better At – Man Are Better At), a tasks and functions allocation method based on this hypothesis. In line with this hypothesis, various descriptions of levels of automation have been proposed. The 10 levels of Automation (LoA) by Parasuraman, Sheridan et Wickens describe different tasks and functions allocations between the human and the system. The higher the level of automation, the more tasks migrate from human to system. These approaches have been the subject of criticism. « MABA-MABA or Abracadabra? Progress on Human–Automation Coordination » of Dekker and Woods highlights that automation leads to new tasks allocated to humans to manage this automation. Moreover, they recall that these approaches hide the cooperative aspect of the human-system couple. To characterize the human-system cooperation, the importance of considering, at design time, the allocation of authority, responsibility, control and the initiative to modify these allocations during the activity was demonstrated. However, the existing approaches describe a high-level design of automation and cooperation early in the design and development process. These approaches does not provide support for reasoning about the allocation of resources, control transitions, responsibility and authority throughout the design and development process. The purpose of this thesis is to demonstrate the possibility to analyze and describe at a low-level tasks and functions as well as the cooperation between humans and the system with automation. This analysis and this description enable to characterize tasks, functions and the cooperation in terms of authority, responsibility, resource sharing and control transition initiation. The aim of this work is to provide a framework and a model-based tooled process to analyze and understand automation. In order to show the feasibility of this approach, this thesis presents the results of the application of the proposed process to an industrial case study in the field of aeronautics.

On-going thesis

In user-centered approaches, the techniques, methods, and development processes used aim to know and understand the users (analyze their needs, evaluate their ways of using the systems) in order to design and develop usable systems that is in line with their behavior, skills and needs. Among the techniques used to guarantee usability, task modeling makes it possible to describe the objectives and activities of the users. With task models, human factors specialists can analyze and evaluate the effectiveness of interactive applications. This approach of task analysis and modeling has always focused on the explicit representation of the standard behavior of the user. This is because human errors are not part of the users' objectives and are therefore excluded from the job description. This vision of error-free activities, widely followed by the human-machine interaction community, is very different from the Human Factor community vison on user tasks. Since its inception, Human Factor community has been interested in understanding the causes of human error and its impact on performance, but also on major aspects like the reliability of the operation and the reliability of the users and their work. The objective of this thesis is to demonstrate that it is possible to systematically describe, in task models, user errors that may occur during the performance of user tasks. For this demonstration, we propose an approach based on task models associated with a human error description process and supported by a set of tools. This thesis presents the results of the application of the proposed approach to an industrial case study in the application domain of aeronautics.

The current European Air Traffic Management (ATM) System needs to be improved for coping with the growth in air traffic forecasted for next years. It has been broadly recognised that the future ATM capacity and safety objectives can only be achieved by an intense enhancement of integrated automation support. However, increase of automation might come along with an increase of performance variability of the whole ATM System especially in case of automation degradation. ATM systems are considered complex as they encompass interactions involving humans and machines deeply influenced by environmental aspects (i.e. weather, organizational structure) making them belong to the class of Socio-Technical Systems (STS) (Emery & Trist, 1960). Due to this complexity, the interactions between the STS elements (human, system and organisational) can be partly linear and partly non-linear making its performance evolution complex and hardly predictable. Within such STS, interactive systems have to be usable i.e. enabling users to perform their tasks efficiently and effectively while ensuring a certain level of operator satisfaction. Besides, the STS has to be resilient to adverse events including potential automation degradation issues but also interaction problems between their interactive systems and the operators. These issues may affect several STS aspects such as resources, time in tasks performance, ability to adjust to environment, etc. In order to be able to analyse the impact of these perturbations and to assess the potential performance variability of a STS, dedicated techniques and methods are required. These techniques and methods have to provide support for modelling and analysing in a systematic way usability and resilience of interactive systems featuring partly autonomous behaviours. They also have to provide support for describing and structuring a large amount of information and to be able to address the variability of each of STS elements as well as the variability related to their interrelations. Current techniques, methods and processes do not enable to model a STS as a whole and to analyse both usability and resilience properties. Also, they do not embed all the elements that are required to describe and analyse each part of the STS (such as knowledge of different types which is needed by a user for accomplishing tasks or for interacting with dedicated technologies). Lastly, they do not provide means for analysing task migrations when a new technology is introduced or for analysing performance variability in case of degradation of the newly introduced automation. Such statements are argued in this thesis by a detailed analysis of existing modelling techniques and associated methods highlighting their advantages and limitations. This thesis proposes a multi-models based approach for the modelling and the analysis of partly-autonomous interactive systems for assessing their resilience and usability. The contribution is based on the identification of a set of requirements needed being able to model and analyse each of the STS elements. Some of these requirements were met by existing modelling techniques, others were reachable by extending and refining existing ones. This thesis proposes an approach which integrates 3 modelling techniques: FRAM (focused on organisational functions), HAMSTERS (centred on human goals and activities) and ICO (dedicated to the modelling of interactive systems). The principles of the multi-models approach is illustrated on an example for carefully showing the extensions proposed to the selected modelling techniques and how they integrate together. A more complex case study from the ATM domain is then presented to demonstrate the scalability of the approach. This case study, dealing with aircraft route change due to bad weather conditions, highlights the ability of the integration of models to cope with performance variability of the various parts of the STS.