惯性质量对2-leg并联机构馈能悬架振型及幅频特性的影响机理

Mechanism of Inertial Mass Influence on the Vibration and Amplitude-frequency Characteristics of 2-leg Parallel Mechanism Energy-fed Suspension

为了研究惯性质量对2-leg并联机构馈能悬架系统振型及幅频特性的影响机理,进行了模型架构、系统振型及幅频特性的理论推导和仿真分析.其中,模型架构中解决的关键问题是惯性质量的理论推导及线性化等效问题,为研究惯性质量对悬架系统振型及幅频特性的影响机理做铺垫.并提出惯性质量变比系数的概念,将惯性质量转化为线性化变量,从而量化分析惯性质量对系统振型及幅频特性的影响.研究结果表明:惯性质量对系统的影响具有两面性,从振型角度分析,惯性质量使得2-leg并联机构馈能悬架系统共振频率提前,随惯性质量变比系数增大,车身振动幅值增大.从幅频特性角度分析,随惯性质量变比系数的增大,车身垂向加速度及悬架动挠度幅频特性函数均在第二个波峰后出现明显差异,车身振动加剧,悬架动挠度振动减小.结合加权法与Matlab+Isight联合仿真可知:通过合理设计2-leg馈能悬架的结构将惯性质量变比系数控制在0.58时,车身振动与车轮振动的加权叠加和最小,隔振效果最佳.

In order to study the influence mechanism of inertial mass on the vibration pattern and amplitude-frequency characteristics of the energy-fed suspension system with 2-leg parallel mechanism,this paper carried out the theoretical derivation and simulation analysis of the model architecture,system vibration patterns and amplitude-frequency characteristics.The key problem solved in the model architecture was the theoretical derivation of inertia mass and linearization equivalence of inertial mass,laying the groundwork for studying its impact on the vibration mode and amplitude-frequency characteristics of the suspension system..The concept of inertial mass ratio coefficient was proposed to transform the inertial mass into a linearized variable,so as to quantitatively analyze its effects on the vibration patterns and amplitude-frequency characteristics of the system.The results show that the influence of inertial mass on the system is two-fold.From the perspective of vibration pattern,the inertial mass advances the resonance frequency of the 2-leg parallel mechanism energy-fed suspension system.With the increase of the inertial mass ratio coefficient,the amplitude of the body vibration increases.From the perspective of amplitude-frequency characteristic analysis,with the increase of inertia mass ratio coefficient,the body vertical acceleration and suspension dynamic deflection amplitude-frequency characteristic function both appear obvious difference after the second wave peak.Vehicle body vibration intensifies,while the suspension dynamic deflection vibration decreases.Combined with the weighting method and Matlab+Isight joint simulation,it can be seen that:through the reasonable design of 2-leg energy-feeding suspension structure to control the inertia mass ratio coefficient at 0.58,the weighted sum of body vibration and wheel vibration is minimized,the vibration isolation effect is optimal.