International audienceThe Anti-lock Braking System (ABS) is the most important active safety system for passenger cars. Unfortunately the literature is not really precise about its description, stability and performance. This research improves a five-phase hybrid ABS control algorithm based on wheel deceleration [1] and validates it on a tyre-in-the-loop laboratory facility. Five relevant effects are modelled so that the simulation matches the reality: oscillations in measurements, wheel acceleration reconstruction, brake pressure dynamics, brake efficiency changes and tyre relaxation. The time delays in measurement and actuation have been identified as the main difficulty for the initial algorithm to work in practice. Three methods are proposed in order to deal with these delays. It is verified that the ABS limit cycles encircle the optimal braking point, without assuming any tyre parameter being a priori known. The ABS algorithm is compared to the commercial algorithm developed by Bosch

Anti-lock Braking System (ABS) is the most important active safety system for passenger cars, but unfortunately the literature is not really precise about its description, stability and performance. This research improves a five-phase hybrid algorithm based on wheel deceleration and validate it on a tyre-in-the-loop laboratory facility. Five relevant effects are modelled so that the simulation matches the reality. Two methods to deal with the time delays are proposed. It can be verified that the limit cycle of the ABS encircle the optimal braking point without having any tyre parameter a priori known.

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In the past few years, the software architecture community has shown an increasing interest in architectural knowledge. In Global Software Development (GSD), software engineering practices are performed at geographically separate locations. With this trend, the management of architectural knowledge becomes even more important due to the geographical, temporal, and socio-cultural distance involved with GSD. Practices for architectural knowledge management in global software development may alleviate challenges associated with this distance. In this paper, we identify to what extent these practices may be implemented using wikis. We relate the practices to generic wiki functionalities and conclude that wikis form a good mechanism to implement a hybrid strategy for managing architectural knowledge in global software development and that a substantial part of the AKM practices may be implemented using wikis.

A method to simulate the forging process and corresponding strain-induced austenitic-martensite phase transformation is formulated in the Eulerian description and its feasibility is examined. The method uses finite volume meshes for tracking material deformation and an automatically refined facet surface to accurately trace the free surface of the deforming material. By means of this finite volume method, an approach has been developed in the framework of metallo-thermo-mechanics to simulate metallic structure, temperature and stress/strain in the forging process associated with phase transformation. The incremental expression on the formulation of the kinetics equation is derived from Tsuta and Cortes' model. A mixture rule is adopted to evaluate the aggregate flow stress of the austenite-martensite affected by the respective flow stresses and phase transformation. This approach has been implemented in the commercial computer program MSC. SuperForge. This is the first report in which the fundamental fr amework is stated and the applicability of the developed method is confirmed using experimental results of the forging of a cylindrical billet. Some practical forging applications are demonstrated in the second report.