Publication

TThe euroFOT project is a large-scale Field Operational Test (FOT) undertaken in Europe in order to evaluate different Advanced Driver Assistance Systems (ADAS) with regard to user related aspects, traffic safety, efficiency and environment. Test vehicles instrumented with data acquisition systems and equipped with different ADAS have been provided by different manufacturers to drivers for everyday driving. The FOT is organised by four operational test centres (vehicle management centres) across Europe: Sweden, France, Italy, and Germany. The goal of the evaluation task is to assess the societal and individual impacts of the ADAS that are tested in the euroFOT project. This deliverable describes the methodology for the impact assessment and evaluation of user related aspects in euroFOT. Data analysis methods are described for each of the work packages undertaken within Sub-Project 6 (SP6) of the project: •User Acceptance and User-Related Aspects Evaluation (WP 6300); •Impact Assessment (traffic safety, traffic efficiency and environment; WP6400) and •Socio-Economic Cost Benefit Analysis (WP6500). euroFOT investigates ADAS that are already present in the market or are mature enough to be tested as commercial functions. The following eight functions were selected: •Longitudinal functions: ◦Adaptive Cruise Control (ACC) and Forward Collision Warning (FCW) together in one bundle (counted as one function) ◦Speed Regulation System (SRS): Speed Limiter (SL) and Cruise Control (CC) •Lateral functions: ◦Lane Departure Warning (LDW) and Impairment Warning (IW) (bundle) ◦Blind Spot Information System (BLIS) •Other functions: ◦Curve Speed Warning (CSW), ◦Fuel Efficiency Advisory (FEA) ◦Navigation System (SafeHMI). Based on the analysis of the objective as well as subjective data (questionnaires) the pre-defined hypotheses in euroFOT were tested in order to answer the research questions related to user acceptance and user related aspects. This Deliverable presents the results of the analysis related to the following research questions: 1.What features of the function, in terms of usability (e.g. accessibility, readability, controllability, compatibility while driving) influence acceptance? 2.What features of the function, in terms of usefulness, influence user acceptance? 3.Does acceptance change with experience? 4.Does trust in the function change with experience? 5.Do drivers find the function more user-friendly with experience? 6.Does frequency of usage of the function change with experience? Overall, the analysis on user related aspects showed a positive effect on acceptance and driving behaviour. The main findings are listed below: 1.In both cars and trucks, ACC+FCW have a very high acceptance, being quite stable over time. Moreover, comfort and safety when driving with the systems active are also perceived as higher. Driver behaviour is influenced by the system, as the drivers feel subjectively that the driving is safer. However, driver’s overall satisfaction in the case of FCW decreased after driving with the system. 2.For the Speed Regulation System (SL+CC), the positive expectations drivers had at the beginning of the FOT remained. Usage was quite stable during FOT, and no significant changes in workload were reported. Behavioral Changes were also observed during FOT, whereby headways increased, large accelerations were less frequent and fuel consumption decreased. The speed analysis indicates that using CC alone increased speeding on all roads apart from motorways, while SL reduced these events by up to 50%. 3.BLIS acceptance scores were very high: over 90% of the rankings were positive, with the system deemed particularly useful on motorways. The scores were quite stable over time. Around 80% of the drivers reported that BLIS increases safety. 4.LDW was ranked as quite useful and effective for increasing driving safety, providing an objective higher usage of turning indicators. However, overall satisfaction with the system was relatively low (when compared with other systems) and decreased over time. Results are different in this case in the Italian case, where only few drivers did not trust the system. Some drivers also experienced a higher workload and, despite rating the system as “quite easy to use”, found the acoustic warning quite annoying. 5.CSW was ranked positively in terms of usability and acceptance. Around 75% of the drivers feel that safety increased when using CSW, finding it most useful on rural roads. 6.In the case of the use of navigation systems, it was found to be used in 40% of all driving time, especially on unfamiliar and long trips. Driving behaviour improved in terms of safety, as no specific safety critical situations were observed when handling the systems. This handling (manual input) usually occurs in low demand situations, and involves a decrease in speed and an increase of time gap to the lead vehicle. Collected data demonstrate that navigation systems have the potential to reduce driving time, distance and fuel consumption, even though they are not reducing time spent in congestions. In any case, built-in navigation systems are ranked higher in acceptance than mobile devices. 7.In the case of IW, it is rated as highly positive in terms of acceptance, satisfaction and usefulness, with these ratings being highly stable over time. Many drivers feel it increases safety, especially on motorways. Trust in the system was equally high, and did not change with time. These results have clear implications for the design, execution, and data analysis of future FOT’s and can, therefore, be used as guidelines for future researches in the field.