The subject of this paper is about an interval linearization method for the sensitivity analysis of manipulators to variations in their geometric parameters. First, the proposed method is presented. Then, three manipulators are used as illustrative examples: The five-bar mechanism, the 3-RRR planar parallel manipulator and the Orthoglide. The benefits and restrictions of the proposed method are also discussed and appropriate indices are derived to show the efficiency of the method. The obtained results are also compared with the results obtained with frequently used methods. The proposed method is simple to implement and provides verified results in low computational time and thus can be applied to complex robots such as the Orthoglide. In particular, the standard linearization method computes unreliable results near singularities, whereas the proposed interval linearization method automatically detects such situations.

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International audienceTransient structural dynamic analyses often exhibit different phases, which enable one to use an adaptive modeling. Thus, a 3D model is required for a better understanding of local or non-linear effects, whereas a simplified beam model is sufficient for simulating the linear phenomena occurring for a long period of time. This paper proposes a method which enables one to switch from a beam to a 3D model during a transient dynamic analysis, and thus, allows one to reduce the computational cost while preserving a good accuracy. The method is validated through comparisons with a 3D reference solutioncomputed during all the simulation

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a b s t r a c tMost often the dynamic analysis of rotor-to-stator rub is performed using 1D models. This leads to a small computational cost, but the reliability of the results is difficult to assess. This research work compares and analyzes the results of 1D and 3D rotor-stator contact problems, for different contact conditions more and less severe. The rotor vibrations are due to rotating imbalance at a given constant rotating speed. In this paper, it is shown that regarding the rotor orbits, the 3D and 1D models responses are very close. However, using a 3D model improves the simulation results. The 1D model actually suffers from limitations resulting from rigid-body displacement assumption of the rotor's crosssection, which originates approximations in the rotor-to-stator contact modeling. Thus, the friction torque generated by the contact is overestimated in a 1D model. The 3D model, however, can present some local effects in the vicinity of the contact zone.