【作者】 张文波；

【导师】 贾建援；

【作者基本信息】 西安电子科技大学 ， 机械电子工程， 2007， 硕士

【摘要】 本文介绍了双稳态理论的国内外研究现状和缺少实验验证的不足，基于小挠度理论和变分原理，推导了弧形微梁结构横向跳转的临界力，并利用有限元软件进行验证的同时，对各种双稳态微结构进行了建模和仿真分析，得到了各种双稳态结构跳转时横向力与结构几何尺寸的关系曲线，为小变形情况下双稳态微结构的设计提供参考。而对于满足各种设计目的的大挠度屈曲梁构件，为了便于对基于大挠度理论得到的倾斜支撑梁结构的大挠度屈曲的力学特性进行验证，设计了数显电子实验平台，采用铍青铜梁作为实验部件，测量了一系列不同长度和角度的斜支梁发生大挠度屈曲时的横向力与位移之间非线性关系，得到了大量有效实验数据，通过与理论分析结果的比较，验证了大挠度屈曲分析理论的正确性，进一步验证大挠度屈曲具有良好的阀值特性和抗干扰能力，为设计大挠度双稳态微加速度开关提供了理论基础与实验依据。 根据大挠度屈曲理论和有效实验数据分析，在实验误差允许范围内，梁屈曲横向力的计算式与实验结果一致，即倾斜支撑梁在变形过程中存在明显的双稳态效应。随着横向位移的增大，横向力迅速增大，当梁发生屈曲后，横向力随位移的增大而减小，直到越过不稳定平衡位置最终达到第二稳态位置，因此大挠度屈曲公式可以用于双稳态开关的设计。更多还原

【Abstract】 The actuality of domestic and international developments of the bistable structures is introduced. The critical transverse force for the arch beam to snap is obtained by utilizing the small deflection theory and the variational principle, and meanwhile the correctness of the deduction can be validated by FEA methods. The nonlinear relations between the transverse forces and the geometrical dimensions of different kinds of bistable micro-structures are given by using the ANSYS software while the micro-beams deflect in small dimensions. For large deflection buckling beam-structures, an digital electrical testing platform is designed to validate the theory deductions of mechanics of the oblique braced beams. The material of the testing beams is be-bronze. Large amount of effective data is obtained while the oblique braced beams with different initial angles and length deflect largely. Comparing with the results of experiments, the correctness of the theoretical analysis is validated. Therefore, we can conclude that analyzing theory for large deflection post-buckling beams deduced by authors of related references is correct and effective.Based on the large deflection buckling theory and effective testing datum, results from the transverse force computation formula get a well agreement with those from experiments, which indicate an obvious bistable effect during the deformation process of the oblique braced beams. The transverse force increases quickly with the displacements of the beam tip. While the beam tip exceeds the critical position and the beam buckles, the transverse force decreases with the increase of the tip displacement until the beam achieves the second stable position. So the formulas of the large deflection post-buckling beams derived by the authors of Xidian University can be used in designing bistable micro-switches.更多还原