Design for Perception - A human-centric approach to the design of driving automation systems based on the driver’s perception

Doctoral thesis, 2023

The automotive industry is rapidly developing driving automation systems (DAS) with the aim of supporting drivers by means of the automation of longitudinal and lateral vehicle control. As vehicle complexity increases and update-over-the-air features are enabling continuous development of vehicle software and functionality, the driver’s understanding of their responsibility and their vehicle’s capabilities and limitations is becoming significantly more important. In order to motivate manufacturers to adopt a human-centric perspective for the development of driving automation systems, the factors influencing the driver’s perception of these systems during their usage needs to be understood. Therefore, the aim of this thesis is to contribute towards the systematic development of DAS from a human-centric perspective.

The core research for this thesis is organised into four empirical studies, embedding a mixed methods research design. Study I aimed to investigate the usage of DAS in different driving contexts by facilitating an online survey to drivers in Germany, Spain, China, and the US.
Study II aimed to explore the driver’s contextual usage of DAS and which factors affect their understanding and employed an explanatory sequential mixed methods approach consisting of a Naturalistic Driving Study (NDS) in the greater Gothenburg area over a 7-month period. This was followed up by in-depth interviews to elicit knowledge about how drivers understand the DAS, and which factors influence their usage.
Study III and Study IV aimed to gain further insights into which factors in the driver’s perception of the DAS affect their understanding and consequent usage of DAS. Thus, Study III applied a Wizard-of-Oz on-road driving study, simulating a vehicle offering a Level 2 and a Level 4 DAS in the San Francisco Bay Area paired with pre- and post-driving in-depth interviews. Finally, Study IV applied a Wizard-of-Oz on-road driving study, simulating a vehicle offering a Level 2 and a Level 3 DAS, and contrasting two different human machine interfaces in Gothenburg, paired with post-driving in-depth interviews.

The results from these studies allowed a contribution to the body of research in a theoretical and practical form. The theoretical contribution is the unification of aspects that shape a driver’s understanding of a DAS into a conceptual model. The unified model describes the process of how this understanding is shaped through the driver’s perception of the DAS. The developed model further facilitated the development of a design toolkit by applying a participatory design approach (Study V) that facilitated co-creation sessions with domain experts (designers of DAS) in an industrial setting, which is considered a practical contribution to the field. The toolkit serves as a common foundation for aligning the motivations and goals of developers, designers, and strategists with regulators.
Consequently, it can support practitioners to: 1. explore possible solutions driven by a systematic approach; 2. identify areas of improvement by applying the lens of the user; and 3. ideate and evaluate design decisions through a structured process. Thus, it facilitates the identification of design, evaluation, and training approaches that promote appropriate usage strategies for drivers and the building of a sufficient understanding of a DAS.