The main goal with this project is to evaluate whether the HMI (Human-Machine Interface) checklist and the DRT (Detection-Response Task) test method are applicable for Euro NCAP's future assessment protocol. This has not been done before in Sweden, the area is new and under development within the Euro NCAP organization. Development work is underway in Australia, and Euro NCAP has had access to the test methods used there by researchers and authorities. We want to evaluate these methods for application in Sweden and Europe. 

 The DRT methodology is used to compare different car brand´s IVIS (In-Vehicle Infotainment Systems) and ADAS (Advanced Driver Assistance Systems) by measuring the effects of cognitive load on driver attention. The DRT method is based on a simple detection-response task where participants respond to relatively frequent artificial stimuli presented with a specified degree of temporal uncertainty. Detection performance, measured in terms of response time and hit rate, is assumed to represent the degree to which attention is affected by the demand, and particularly the cognitive load component imposed by the secondary task under evaluation. Longer reaction times and reduced hit rate are indicative of higher cognitive load. 

The checklist is divided in three parts, training part, part 1 and part 2. Part 1 was performed by an authorized test leader. The tasks were performed according to the checklist, but the visual and bimanual load was irrelevant due to when you stand still with the vehicle there is no need to look on the road or keep both hands on the steering wheel while performing the tasks. The test result when using the checklist showed no big differences between test vehicle one (V1) and test vehicle two (V2), when using the centre stack or the voice command. When it comes to the voice command it seems like it doesn’t matter if you are driving or not, the appreciated cognitive load doesn´t increase for the test group when using voice command. Regarding the steering wheel control V2 is getting higher score from both the test leader and the test group in comparison to V1. An explanation to this may be the difference in the choice of interface. V1 is equipped with scroll wheel and V2 is equipped with touchscreen. A reflection after test Part 1 is that it would give more if the test leader performed both primary and secondary tasks at the same time. No time was being measured during this part.  

 Part 2. was performed on a test track with a test person and an authorized test leader in the car. The test person performed both primary and secondary tasks at the same time, while using the DRT. The test person drove at 70km/h on the Rural Road while performing the tasks according to the checklist. In this part you get an overview of visual, cognitive and bimanual load. Just like in Part 1, the test result when using the DRT shows a big difference between V1 and V2 when using the steering wheel control. Navigation and calling sticks out with high cognitive load during the performance of this tasks because writing with the steering wheel's touch function is cumbersome and time-consuming and should not be done while driving for safety reasons. The voice command systems have potential for improvement, but when it works, it´s the safest option. A reflection after test Part 2 is that it´s unsuitable to perform certain tasks while driving on public roads as some test persons swayed over the centre line while the test was in progress. Because of that it will be more time and cost consuming due to the need of a test track compared to in Part 1. No reference lap was made so it wasn´t possible to compare the reaction time with or without tasks.  Recommends the checklist and the DRT for HMI developers. 

 This project can be of use for Euro NCAP in order to develop a HMI test procedure evaluating the performance and rating the HMI system in vehicles. This can lead to giving customers the possibility to choose vehicles with higher safety.