Due to its low environmental impact, earth construction has received much consideration in recent years. Nevertheless, its development remains limited due to low production rate. Recent developments have been made to improve earth-based materials mixdesign and processing methods. Simultaneously, digitally based construction methods have been introduced in the field of construction especially for cement-based materials application. Among these new techniques, the so-called 3D printing by extrusion deposit has been the most intensively studied. In this study, we assess the possibility of adapting this technique to earth-based material. After making the earth's rheological behaviour suitable for 3D printing, a laboratory-scale printing has been carried out and the printed samples have been mechanically tested.

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In this paper, a coupling methodology is involved and improved to correct the tool path deviations induced by the compliance of industrial robots during an incremental sheet forming task. For that purpose, a robust and systematic method is rst proposed to derive the elastic model of their structure and an ef cient FE simulation of the process is then used to predict accurately the forming forces. Their values are then de ned as the inputs of the proposed elastic model to calculate the robot TCP pose errors induced by the elastic deformations. This avoid thus a rst step of measurement of the forces required to form a test part with a stiff machine. An intensive experimental investigation is performed by forming a classical frustum cone and a non-symetrical twisted pyramid. It validates the robustness of both the FE analysis and the proposed elastic modeling allowing the nal geometry of the formed parts to converge towards their nominal speci cations in a context of prototyping applications.

International audienceThis paper presents the design optimization of a Delta-like robot manipulator with respect to multiple global stiffness objectives. For this purpose, a systematic elasto-geometrical modeling method is used to derive the analytical manipulator stiffness models by taking into account their link and joint compliances. The models are then involved within a statistically sensitivity analysis of the influence of the geometric parameters on four global indices that describe the structure stiffness over the workspace. Multi-Objective Genetic Algorithm, i.e. Pareto-optimization, is taken as the appropriate framework for the definition and the solution of the addressed multi-objective optimization problem. Our approach is original in the sense that it is systematic and it can be applied to any serial and parallel manipulators for which stiffness is a critical issue

International audienceThis paper presents a systematic procedure for the elastodynamic modeling of industrial robots that is applicable to either serial or parallel manipulators. This procedure is based on a 3-D space generalization of the equivalent rigid link system (ERLS) description, the finite-element method (FEM), and the Lagrange principle. It considers flexible links and joints, and leads to generic equations of motion expressed according to the angles of the actuated joints and the independent elastic degrees of freedom. An efficient identification process through modal analysis is detailed, and the description of damping and joint behavior according to the model application is discussed. The method is applied to a 3-D delta-like parallel structure and successfully validated through an experimental impact testing-based modal analysis