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Recursive filtering with multimodal likelihoods and transition densities on periodic manifolds is, despite the compact domain, still an open problem. We propose a novel filter for the circular case that performs well compared to other state-of-the-art filters adopted from linear domains. The filter uses a limited number of Fourier coefficients of the square root of the density. This representation is preserved throughout filter and prediction steps and allows obtaining a valid density at any point in time. Additionally, analytic formulae for calculating Fourier coefficients of the square root of some common circular densities are provided. In our evaluation, we show that this new filter performs well in both unimodal and multimodal scenarios while requiring only a reasonable number of coefficients.

Directional estimation is a common problem in many tracking applications. Traditional filters such as the Kalman filter perform poorly because they fail to take the periodic nature of the problem into account. We present a recursive filter for directional data based on the Bingham distribution in two dimensions. The proposed filter can be applied to circular filtering problems with 180 degree symmetry, i.e., rotations by 180 degrees cannot be distinguished. It is easily implemented using standard numerical techniques and suitable for real-time applications. The presented approach is extensible to quaternions, which allow tracking arbitrary three-dimensional orientations. We evaluate our filter in a challenging scenario and compare it to a traditional Kalman filtering approach.

This project, under 6th framework programme of the European Commission, aims to provide SME's with the cost-effective knowledge to provide the automotive industry with light forged magnesium-based alloys components. Low density, high mechanical properties and total recyclability pairing with the advantages provided by forging processes enable to lighten vehicles therefore reduce pollutant emissions.

This paper summarises the current situation and knowledge on magnesium forging as well as its prospects for further development. It is structured according to the sequential areas of the processing chain: feedstock, forging process, finishing, and components. Attention is given to some specific metallurgical aspects of magnesium forging and the resulting mechanical properties. Further, the weight-saving potential of magnesium forgings over conventional solutions (notably in aluminium), prospective application areas (especially for transport means), demonstrator components and costs are addressed.

Overall goal of the MagForge project is to provide tailored and cost-effective technologies for the industrial manufacturing of magnesium forged components. Scientific and technological aspects are new alloys/feedstock materials with improved performance, forging process modeling and design tools with a satisfying level of predictability, machining technology for safe and rational finishing of the forgings, and typical demonstrator components to validate results. The targeted advancements are to enable high-volume applications of magnesium forgings. This paper gives an overview of the MagForge project and the first results. The commercial magnesium alloys AZ80 and ZK60 were investigated. With respect to the different microstructure of the alloys the mechanical properties of the feedstock, the parameters of the forging process and the mechanical properties of the forging parts will be presented and discussed. The results show that the magnesium alloys offer the possibility to produce parts with complex geometries similar to aluminum forging parts.

Wrought magnesium alloy products have favourable attributes compared to castings with regard to mechanical properties. In addition they provide a complementary class of shapes and geometries. These are the current drivers for developments within the field of magnesium forging technology. Within this context, the European research project MagForge is being conducted with the overall goal to provide tailored and cost-effective technologies for the industrial manufacturing of forged magnesium alloy components. One of the present impediments to magnesium forging is the availability of suitable alloys: Forgeability in terms of the robustness of processing windows and the resulting product quality in terms of mechanical performance need to be improved. Hence this is one of the main topics of the project. This paper reports on the progress made in this particular area. The strategy adopted for advancement consists in inducing grain refinement and stabilisation of the microstructures by rare-earth and complementary modifications of the commercial AZ80 and ZK60 forging alloys. In line with common practice, forging slugs were prepared from cast billets by preextrusion. The quality of the modified alloy slugs is assessed on the basis of laboratory-scale cone-forging trials. The results show a significant improvement over the existing alloys.