Hu Gaofeng, Xin Wendong, Zhang Min, Chen Guangjun, Man Jia, Tian Yanling
School of Mechanical Engineering, Tianjin University of Technology and Education, Tianjin 300222, China.
Tianjin Key Laboratory of High Speed Cutting and Precision Machining, Tianjin 300222, China.
Micromachines (Basel). 2024 Aug 19;15(8):1050. doi: 10.3390/mi15081050.
In this paper, a fast positioning platform (FPP) is proposed, able to meet simultaneously the requirements of large stroke and high frequency response, developed based on a PZT (piezoelectric actuator) and a quad-parallel flexible mechanism, for application in precision machining. The FPP is driven by a high-stiffness PZT and guided by a flexible hinge-based mechanism with a quad-parallel flexible hinge. The proposed quad-parallel flexible hinge mechanism can provide excellent planar motion capability with high stiffness and good guiding performance, thus guaranteeing outstanding dynamics characteristics. The mechanical model was established, the input and output characteristics of the FPP were analyzed, and the working range (output displacement and frequency) of the FPP was determined. Based on the mechanical model and the input and output characteristics of the FPP, the design method is described for of the proposed FPP, which is capable of achieving a large stroke while responding at a high frequency. The characteristics of the FPP were investigated using finite element analysis (FEA). Experiments were conducted to examine the performance of the FPP; the natural frequency of the FPP was 1315.6 Hz, while the maximum output displacement and the motion resolution of the FPP in a static state were 53.13 μm and 5 nm, respectively. Step response testing showed that under a step magnitude of 50 μm, the stabilization times for the falling and rising edges of the moving platform were 37 ms and 26 ms, respectively. The tracking errors were about ±1.96 μm and ±0.59 μm when the amplitude and frequency of the signal were 50 μm, 50 Hz and 10 μm, 200 Hz, respectively. The FPP showed excellent performance in terms of fast response and output displacement. The cutting test results indicated that compared with the uncontrolled condition, the values of surface roughness under controlled conditions decreased by 23.9% and 12.7% when the cutting depths were 5 μm and 10 μm, respectively. The developed FPP device has excellent precision machining performance.
本文提出了一种快速定位平台（FPP），该平台基于压电陶瓷（PZT）和四平行柔性机构开发，能够同时满足大行程和高频响应的要求，适用于精密加工。FPP由高刚度PZT驱动，并由基于柔性铰链的四平行柔性铰链机构导向。所提出的四平行柔性铰链机构能够提供具有高刚度和良好导向性能的出色平面运动能力，从而保证卓越的动力学特性。建立了力学模型，分析了FPP的输入输出特性，并确定了FPP的工作范围（输出位移和频率）。基于FPP的力学模型和输入输出特性，描述了所提出的FPP的设计方法，该方法能够在高频响应的同时实现大行程。使用有限元分析（FEA）研究了FPP的特性。进行了实验以检验FPP的性能；FPP的固有频率为1315.6 Hz，而其在静态下的最大输出位移和运动分辨率分别为53.13μm和5nm。阶跃响应测试表明，在50μm的阶跃幅值下，移动平台下降沿和上升沿的稳定时间分别为37ms和26ms。当信号幅值和频率分别为50μm、50Hz和10μm、200Hz时，跟踪误差分别约为±1.96μm和±0.59μm。FPP在快速响应和输出位移方面表现出优异的性能。切削试验结果表明，与未控制的情况相比，在切削深度分别为5μm和10μm时，控制条件下的表面粗糙度值分别降低了23.9%和12.7%。所开发的FPP装置具有优异的精密加工性能。
