0 引言
1 振动试验夹具设计流程
2 振动试验夹具动力学结构优化设计方法
2.1 结构预应力模态分析方法
2.2 拓扑优化设计方法
2.3 参数优化设计方法
3 舵机控制驱动器振动试验夹具设计
3.1 舵机控制驱动器振动试验夹具初始模型设计
3.2 初始振动夹具拓扑优化
3.3 模型重构及预应力模态分析
图11 优化后X轴向试验振动夹具的前4阶模态示意图Fig.11 Schematic diagram of the first 4 modes of the optimized vibration fixture for axis X test |
图12 优化后Y轴向试验振动夹具的前4阶模态示意图Fig.12 Schematic diagram of the first 4 modes of the optimized vibration fixture for axis Y test |
表1 振动夹具拓扑优化前、后主要参数对比Table 1 Comparison of main parameters of vibration fixture before and after topology optimization |
| Status | Mass/kg | The first natural frequency/Hz | The second natural frequency/Hz | The third natural frequency/Hz | The fourth natural frequency/Hz | Static strain energy/(kN·mm) | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Axis X | Axis Y | Axis X | Axis Y | Axis X | Axis Y | Axis X | Axis Y | Axis X | Axis Y | ||
| Before optimization | 6.89 | 2 126.54 | 1 810.17 | 2 327.76 | 2 374.57 | 3 588.80 | 2 590.79 | 4 753.80 | 3 079.93 | 2.23 | 7.32 |
| After optimization | 4.64 | 2 033.13 | 1 576.74 | 2 239.02 | 2 077.46 | 3 332.78 | 2 313.09 | 4 108.68 | 2 960.64 | 5.86 | 8.44 |
3.4 随机振动仿真分析
图15 优化前振动夹具响应点加速度幅频曲线Fig.15 Acceleration amplitude-frequency response curve of response points of fixture before optimization |
图16 优化后振动夹具响应点加速度幅频曲线Fig.16 Acceleration amplitude-frequency response curve of response points of optimized fixture |
表2 响应点加速度均方根值GRMS与品质因数QTable 2 GRMS value and quality factor of response points |
| Response point | Before optimization | After optimization | ||
|---|---|---|---|---|
| GRMS/g | Q | GRMS/g | Q | |
| A | 10.768 | 1.397 | 11.859 | 1.539 |
| B | 10.734 | 1.393 | 11.609 | 1.641 |
| C | 8.884 | 1.153 | 8.530 | 1.107 |
| D | 23.814 | 3.091 | 23.967 | 3.111 |
| E | 15.585 | 2.023 | 14.409 | 1.870 |
| F | 17.729 | 2.301 | 20.961 | 2.720 |
3.5 参数优化设计
图18 优化参数x1与第一阶固有频率和方向加速度关系曲线Fig.18 Relationship curve of optimization parameter x1、the first natural frequency and directional acceleration |
4 试验验证
表3 试验结果及与仿真结果偏差Table 3 Experimental results and deviation from simulation results |
| Test point | GRMS/g | Deviation form simulation/% | Q |
|---|---|---|---|
| A | 11.577 | 1.6 | 1.506 |
| B | 11.269 | 1.8 | 1.466 |
| C | 7.902 | 5.6 | 1.028 |
| D | 21.102 | 11.3 | 2.735 |
| E | 13.112 | 6.5 | 1.699 |
| F | 18.811 | 8.5 | 2.438 |