Publication type: Conferences

The increasing use of Autonomous Underwater Vehicles (AUV) in industrial or scientific applications makes the vehicle localization one of the challenging questions to consider for the mission success. Graph-SLAM has emerged as a promising approach in land vehicles, however, due to the complexity of the aquatic media, these systems have been rarely applied in underwater vehicles. The few existing approaches are focused on very particular applications and require important
amounts of computational resources, since they optimize the coordinates of the external landmarks and the vehicle trajectory, all together.This paper presents a simplified and fast general approach for stereo graph-SLAM, which optimizes the vehicle trajectory, treating the features out of the graph. Experiments with robots in aquatic environments show how the localization approach is effective underwater, online at 10fps, and with very limited errors. The implementation has been uploaded to a public repository, being available for the whole scientific community.

This paper describes SOAcom, a communication model as well as a development process to characterize and adapt automotive network protocols to Service-based Driver Assistance Systems (DAS). Future DAS for articulated vehicles like a car with a caravan are characterized by a dynamic software and hardware architecture. In these systems Service-orientation is a promising approach. One major demand to be able to deploy such systems in an automotive environment is the ability to allow Service communication through the specialized automotive networks. This paper describes a development process to define a communication model that is built up by mechanisms which are necessary to allow this Service communication. The development process, consisting of four phases, is tested by defining a communication model for a Service-based DAS on the Controller Area Network (CAN). The result is then evaluated by means of a set of experiments.

Flexible Time-Triggered communication (FTT) allows a distributed embedded system (DES) to adapt to changing real-time requirements at runtime. This facilitates the continuous operation of the DES under dynamic environments that
change over time. However, for continuous operation, high reliability in the nodes of the DES is also crucial. This can be achieved using node replication, as long as failure independence between replicas is ensured, which calls for
preventing the propagation of errors. Our goal is to prevent the propagation of Byzantine node behaviours and to ensure that local errors in the channel cannot disturb the global communication. For this, we construct the HaRTES/PG switch, a new switch based on the HaRTES implementation of FTT for Ethernet. This paper presents as a first step a study of the possible errors that may lead to Byzantine node behaviours and a global communication disturbance in HaRTES, as well as some ideas on how to prevent the propagation of these errors in HaRTES/PG.

The interest to use Switched Ethernet technologies in real-time communication is increasing due to its absence of collisions when transmitting messages. Nevertheless, using COTS switches affect the timeliness guarantee inherent in potentially overflowing internal FIFO queues. In this paper we focus on a solution, called the FTT-SE protocol, which is developed based on a master-slave technique. Recently, an extension of the FTT-SE protocol has been proposed where the transmission of messages are controlled using multiple master nodes. In order to guarantee the correctness of the protocol, the masters should be timely synchronized. Therefore, in this paper we investigate using a clock synchronization protocol, based on the IEEE 1588 standard, among master nodes and we study the effects of this protocol on the network performance. In addition, we present a formal verification of this solution by means of model checking to prove the correctness of the FTT-SE protocol when the clock synchronization protocol is applied.