The opposite of the former approach may also be the case -- that is to force an eigenfrequency to achieve a certain value. This may be realized using constraint functions. DRESP ID_NAME = dresp_eig_2 DEF_TYPE = SYSTEM TYPE = DYN_FREQ LC_SET = Modal,All,2 END_ OBJ_FUNC ID_NAME = max_dresp_eig_2 DRESP = dresp_eig_2 TARGET = MAX END_ CONSTRAINT ID_NAME = con_dresp_eig_2_le_15Hz DRESP = dresp_eig_2 MAGNITUDE = ABS LE_VALUE = 15. END_ OPTIMIZE ID_NAME = opt DV = my_design_nodes STRATEGY = BEAD_SENSITIVITY OBJ_FUNC = max_ dresp_eig2 CONSTRAINT = con_dresp_eig_2_le_15Hz END_ The second eigenmode will be maximized, but because of the constraint it may not become higher than 15. Hz. | |||||||