On the Suitability of Estelle for Multimedia Systems

Formal Description Techniques have been widely used for the specification of traditional networked applications. They have not been applied to the specification of new applications such as multimedia systems yet. In this paper, we examine the FDT Estelle with respect to its suitability for multimedia system specification and automatic derivation of efficient implementations. We show that it is possible to specify certain aspects of multimedia systems, but that Estelle is not sufficient for others. The derived implementations often perform badly. We show the reasons and propose to use a slightly modified Estelle syntax and semantics to solve the problems. The implemented solution was tested successfully

CityMobil: Human Factor Issues Regarding Highly-automated Vehicles on an eLane

In the European project ‘CityMobil’ the human factors aspects of (semi) autonomous driving are investigated. Systems in the car and in the driving environment enable the driver to drive (semi) automatically in a driving lane (eLane). One of the issues is the optimal interface for the change from automated to manual control and vice versa. Therefore, we conducted a driving simulator experiment with the aim to design and test the difference between a vocal and acoustic user interface, for a vehicle driven both manually and automatically. In the experiment the behavior of 24 drivers was observed, focusing on the transition of control and the occurrence of system errors. The performance of the transition of control was adequate for both interfaces at the beginning and ending of an eLane. In case of system failure, 15% of drivers failed to take timely control of the car for both interfaces. However if drivers regained control, they had a shorter response time to initiated the transfer of control to a manual mode with the vocal interface. Moreover, a subjective questionnaire showed that the vocal interface had a higher acceptance and perceived usability, than the acoustic interface. This study suggests that the vocal interface was preferred by the participants and can be recommended for the HMI of (semi) automated vehicles, especially when providing warnings about the system’s malfunctionin