3-P(4S)并联平台振动特性分析与实验验证

为了研究3-P(4S)并联平台作为振动台的应用前景,根据其动力学模型构建了振动方程,并根据其驱动器特性对振动方程进行简化处理,得到其固有频率和正则固有振型,并在ADAMS仿真软件上对理论振动模型进行了仿真验证,误差范围在0.5%以内。对3-P(4S)并联平台的振动特性进行了分析,包括固有频率随运动位置变化特性和灵敏度特性。通过力锤敲击法进行了3-P(4S)并联平台的模态实验,对实验所得的时域信号进行傅里叶变换得到频域波形,其固有频率的实验值和理论计算值的误差在3%以内,验证了理论分析,说明3-P(4S)并联平台可应用于振动模拟及振动测试等领域。

Vibration Characteristics Analysis and Experimental Validation of 3-P(4S) Parallel Platform

The 3-P(4S) parallel platform has three translational degrees of freedom and excellent decoupling performances. In order to analyze the application prospect of 3-P(4S) parallel platform as a vibration platform, first of all, the vibration model was introduced according to its dynamic model, and vibration equation was simplified according to the characteristics of the driving units. And the vibration frequencies and regular vibrations were obtained. Furthermore, the vibration model was verified by the simulation in ADAMS software, and the error was within the range of 0.5%. Besides, the vibration characteristics of the 3-P(4S) parallel platform were analyzed, including the natural frequency with the change of position and sensitivity characteristics. Finally, the modal test of the 3-P(4S) parallel platform was carried out based on the hammering method, and the modal test results were the time domain signals, and then the time domain signals were converted into frequency domain signals by Fourier transformation. The experimental results of natural frequencies were obtained by the frequency domain waveforms from the modal test, and the errors of the natural frequencies and the theory calculated ones were within the range of 3%, which proved the correctness of theoretical analysis, and indicated that the 3-P(4S) parallel platform could be applied to the fields of vibration simulation and vibration test.