三维随机振动环境下MEMS加速度计输出特性分析

摘要

对MEMS惯性测量单元进行了三维随机振动试验,初步探讨了MEMS惯性测量单元在三维振动试验条件下的故障模式:3个轴的MEMS加速度计均出现了零位偏移,该现象在单轴振动试验环境中并没有出现.从理论和仿真分析了该现象产生的机理,提出了解决办法并通过了试验验证.结果表明:三维振动比单轴的振动更能接近真实的振动环境,结构被激发的模态更丰富.通过采取措施,减小了加速度计的零偏值,从9.4m/s2降至1.97m/s2.%Performance of MEMS inertial measurement unit is tested in three-axis random vibration environ-ment.Failure mode of the IMU in the three-axis random vibration environment is discussed firstly and it didn't occur in the one-axis vibration environment.The cause of the failure is analyzed in theory and simulation.The way to decrease the failure mode is produced and validated by experiment.The result indicates that three-axis vibration environment is more authentic than one-axis,which can excited more modes of the structure.Zero bias of MEMS accelerometer is reduced after our meas-ure: 9.4m/s2to 1.97m/s2.