.. _V2.01.002:

**v2.01.002** SDLD02 - Spring mass system with 8 degrees of freedom
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**Summary:**

This two-dimensional problem consists in looking for the frequencies and the modes of vibration of a mechanical structure composed of masses and springs. This Structural Mechanics test case corresponds to a dynamic analysis of a discrete model with linear behavior.

This test allows a complete validation of the discrete stiffness and mass modeling options (without finite elements) offered by the AFFE_CARA_ELEM command. Four different models are proposed: two models for discrete elements in translation and two others for discrete elements in translation/rotation. In addition, various functionalities of the commands CALC_MODES (calculation of values and eigenvectors) and NORME_MODE (definition of the norm of an eigenvector) are tested.

This test refers to test VPCS, but it has been modified. In fact, the *Code_Aster* test orients the mechanical system on an axis :math:`\mathrm{3y}\mathrm{=}\mathrm{4x}`, which makes it possible to validate the entry of data in a local coordinate system.


.. toctree::
    :hidden:

    self

.. toctree::
    :maxdepth: 2
    :numbered:

    Probl_me_de_r_f_rence
    Solution_de_r_f_rence
    Mod_lisation_A
    Mod_lisation_B
    Mod_lisation_C
    Mod_lisation_D
    Mod_lisation_E
    Mod_lisation_F_et_G
    Synth_se_des_r_sultats