Development of a human-machine interface for highly automated trucks : a user centred study

Abstract: Self-driving vehicles are expected to be increasingly common and with new automation technologies new challenges arise. Truck drivers of today that are accustomed to manual driving will face new work tasks in highly automated trucks. Rather than being an active part in the driving procedure, the drivers will merely be monitoring the automated systems. This study aimed to investigate the challenges truck drivers may face when going from a manually driven truck to a highly automated. Findings from theoretical research and user studies were used to develop concepts for a human-machine interface supporting the drivers’ trust, situation awareness, state and efficiency. The study was user centred and utilised a pre-defined persona to which the concepts were adapted. The problem identification phase consisted of user studies in Germany and Sweden comprising observations and semi-structured interviews. A theoretical research was conducted to further explore factors important for automated driving. The findings were summarised in a product design specification where user needs, user requirements and common scenarios were presented. The concepts were designed based on the specification and utilised a concept development process consisting of ideation, evaluation and development. The user was involved during the entire process. The concept development resulted in three concepts that together supported most of the requirements in the specification. User tests were performed for two of the concepts, aiming to assess the usability, learnability, trust and overall impression. In addition, the tests aimed at gaining insights regarding potential improvements. The tested concepts achieved the set goals, but additional tests where the concepts are tested with a baseline are necessary in order to evaluate them against existing interface solutions. Qualitative data from the tests was compiled and the improvement suggestions form the basis for the further development of the concepts.