ABSTRACT
ABSTRACT: A method for the experimental evaluation of the controllability of interacting advanced driver assistance systems (ADAS) is presented at the beginning of this paper. Here, driving situations where particular ADAS are acting within, at or beyond their system limits or during and after system failures have been implemented into a static driving simulator. According to the recommendation of the Code of Practice (CoP) each situation has been assessed to select three critical driving situations. The second part of the paper describes two driving simulator studies to evaluate the controllability of four interacting ADAS (Automatic Emergency Brake Assist (AEB), Adaptive Cruise Control (ACC), Lane Keeping Assist (LKA) and Lane Change Decision Aid System (LCDAS) in critical driving situations. Each study is based on a with-in subjects design. In these studies, each participant was driving each of the three scenarios (“Stationary Obstacle Avoidance”, “Braking Object Vehicle” and “Three-Lane Motorway”) without and with ADAS. The recorded physical and physiological data and the subjective perceptions of the participants were analysed. One of the findings was e.g., that some drivers became confused when ACC was braking while LKA overlaid a steering torque during a system failure (3 Nm steering torque ramp) in the scenario “Three-Lane Motorway”. It could also be shown, that accidents have happened during an evasive manoeuvre where ACC has accelerated and LKA had a overlaying steering torque. Based on the results of the study, functional improvements which might enhance the interaction of ADAS have been derived and are presented in this paper. These improvements have been tested and evaluated in a second replication driver simulator study. The results of this study show an improvement of the controllability when the vehicle in front is detected earlier. It also confirms that an unexpected braking and warning of an Adaptive Cruise Control and an overlay of a steering moment lead to an uncontrollable behaviour.
