基最大的基座的拓化 - Comsol.PDF

基 最大的基座的拓化 高 1, 震宇2 1中科院春光精密机械物理究所 ，春 ，中 ；中科院大 ，北京 ，中 。 2 中科院春光精密机械物理究所 ，春 ，中 Abst ract In order to satisfy the requirements of modern range measuring technology , photoelectric theodolite s gradually develop towards lightweight and minitype de sign. As a consequence , the mobile theodolite is becoming a hot spot recently . New requirements are raised for the theodolite base ( igure 1), which is an e ssential part of photoelectric theodolite s. Namely , the eigenfrequencie s should be high enough to satisfy the characteristic s of vibration of the whole sy stem, which is also the difficulty of re search. The topology optimization of theodolite base is pre sented in this article in order to improve the fundamental eigenfrequency . A mathematical model who se objective is the fundamental eigenfrequency is e stablished based on SIMP topology optimization method. The optimization model is solved using Structural Mechanic s Module of COMSOL Multiphy sic s® software . The sensitivity analy sis is realized using the Subdomain Expre ssions with the formulation derived from the vibration equation. Combined with filtering methods, a clear topology structure is obtained. The numerical example demonstrate s the fundamental eigenfrequency of the optimized theodolite ( igure2) base is about 28% higher than before , Additionally , the first five natural frequencie s of the theodolite base are all improved to some extent, proving the validity of the de sign. Reference [1] Bendsøe , M. P ., and Sigmund, O . Topology optimization: theory , methods and applications [M]. Springer, Berlin (2003). [2] Du , J. B., and Olhoff , N . Topological de sign of freely vibrating continuum structure s for maximum value s of simple and multiple eigenfrequencie s and frequency gaps [J]. Struct Multidisc Optim 34, 9 1– 110 (2007). [3] Sigmund, O . A 99 line topology optimization code written in Matlab [J]. Struct Multidisc Optim 2 1,