Abstract
Advanced Driver Assistance Systems (ADAS) are on-board vehicle systems supporting the driver in their primary driving task. They assist the driver, without taking over the driving task completely, thus these new technologies will require interaction while driving and, as a result, the risk of divided attention lurks. Cooperative systems based on V2x communications offer promising opportunities for automotive safety and traffic efficiency together with timing and cost reduction in terms of system design and development. Under preventive safety, cooperative assistance systems increase in-vehicle safety systems functionality, enlarging driver’s time space perception as well as the quality and reliability of the environment data, and therefore enhancing driver’s response to incoming events. The aim of this paper is to present an on-board driving assistance system, Forward Collision Warning (FCW), based on V2V communications, in addition to an intuitive Human – Machine interface (HMI), meant to assist the driver. Usually, this kind of systems uses external perception technologies where as in this case, the system is based on positioning and cooperative V2V communications technologies. On the other hand, Human – Machine interfaces are mainly designed with the purpose of adapting to human’s behaviour, skills and capacities, as well as their needs, taking also into account that, especially for car manufactures, it is very important to use a clear and intuitive information representation within the vehicle as the display should be comprehensible without reading a manual. The FCW based on V2V communications discussed in this paper is divided into two subsystems: subject vehicle (host vehicle where the system is installed) and the preceding vehicle, or target. There are two computers on each vehicle, which set up the system: control and communication gateway computers. Additional sensors, available on subject and target, such as USB/Bluetooth GPS receiver provide vehicle’s speed and position. Urban and interurban scenarios (low and high speed) were selected for system testing. Derived from the tests carried out, it can be concluded that the communications range is high enough to warn driver earlier, reducing the risk of a potential dangerous driving situation. The communication technology used (802.11a, at 5,8GHz) has shown an acceptable performance on the field tests in terms of coverage (up to 400m, line-of-sight) and link robustness. Related to vehicle and driver interaction aspects, all the tests were completed in a virtual environment using a driving simulator with urban and motorway scenarios, in order to reveal the best HMI to interact with driver. In addition to the registration of the drivers’ reaction time (DRT), acceptance was assessed with the technique developed by Van der Laan, Heino, and De Waard [1]. Finally, this pilot study has shown benefits in terms of safety when using an adaptive HMI that has been selected based on two parameters: acceptance and DRT’s reduction results.
KEYWORDS – Driving performance, Human – Machine Interaction (HMI), acceptance, Advanced Driver Assistance Systems (ADAS) and V2X communications.