传递函数在气动式振动台动力学响应分析中的应用

针对一类新型可靠性强化振动试验设备——气动式振动台,根据矩形薄板横向弯曲振动理论,建立了气动式振动台的力学模型,采用能量法(Rayleigh-Ritz法)近似计算了振动台面的固有频率和归一化条件下的正则振型,并对数值计算结果进行了实验验证。在此基础上,考虑到实际气动式振动台复杂的激励载荷,即九个不同位置气锤产生的周期性激励信号,通过计算振动台面气锤安装位置(输入)与响应位置(输出)之间的传递函数,进一步研究了振动台面的动力学响应,并通过有限元仿真验证了本文的理论计算结果。研究表明:传递函数法是分析气动式振动台动力学响应的有效方法,且具有较高的计算精度。

Application of Transfer Function to Analyzing Dynamic Response of Repetitive Shock Machines

Repetitive shock(RS) machines have some disadvantages,which confine the application of RS machines to the reliability enhancement testing of electronic accessories,it is therefore necessary to study how to improve the RS machines function.This paper firstly builds the model of RS machine by the vibration theory of elastic rectangular plates,then applies the Rayleigh-Ritz method of elastic rectangular plates to solving the natural frequencies and mode shapes of the vibration table.Furthermore the transfer function is derived between input and output,and the dynamic response of the vibration table is calculated according to the exciting signals generated by nine vibrators.Finally the theoretical conclusions are proved by finite element simulation.