CAJ | 학술논문

在应用六自由度振动台进行高频振动测试试验时,若台体结构被激发产生共振,则会影响测试结果的准确性.为保证台体的共振频率在工作频带之外,同时使台体重量更轻,文章提出基于二级多点逼近算法的六自由度振动台台体结构优化方法.首先建立台体结构的有限元模型,并根据实际应用工况确定台体连接面法向位移约束的边界条件,以壳、梁单元的截面尺寸和外形半径大小为设计变量,建立以台体结构一阶固有频率和静强度为约束、质量最小为目标的模型.然后,利用二级多点逼近算法对模型进行尺寸优化,并以人机交互的方式实现外形半径的优化,得到满足约束条件的优化解.最后依据优化结果设计与制造出台体结构,并完成台体样机.该台体结构实现了轻量化设计要求并应用于振动试验,验证了该结构优化方法的有效性.
재응용륙자유도진동태진행고빈진동측시시험시,약태체결구피격발산생공진,칙회영향측시결과적준학성.위보증태체적공진빈솔재공작빈대지외,동시사태체중량경경,문장제출기우이급다점핍근산법적륙자유도진동태태체결구우화방법.수선건립태체결구적유한원모형,병근거실제응용공황학정태체련접면법향위이약속적변계조건,이각、량단원적절면척촌화외형반경대소위설계변량,건립이태체결구일계고유빈솔화정강도위약속、질량최소위목표적모형.연후,이용이급다점핍근산법대모형진행척촌우화,병이인궤교호적방식실현외형반경적우화,득도만족약속조건적우화해.최후의거우화결과설계여제조출태체결구,병완성태체양궤.해태체결구실현료경양화설계요구병응용우진동시험,험증료해결구우화방법적유효성.
When a shaker of six degrees of freedom (6-DOF) is applied in a high frequency vibration test, the table of the shaker might easily be in the state of resonance, which will greatly influence the accuracy of the test results. To make the first-order natural frequency of the 6-DOF shaker's table higher than the working frequency and reduce its mass, an optimization approach for the table based on the two-level multi-point approximation method is proposed. Firstly, the finite element model of the table is established, including the boundary conditions according to the actual working situation. Then, the structure model's shell and beam properties and the radius of the shape are taken as the design variables, with the constraint of the first-order natural frequency and the static strength, a structure optimization model is established to minimize the mass. In the optimum solution, the two-level multi-point approximation method and the man-machine interactive method are, respectively, adopted in the size and shape optimizations. Based on the results after optimization, a prototype including the table structure is designed and manufactured. The structure can meet the lightweight design requirement and is used in the vibration test, thus this optimization approach is validated.