【摘要】 下一代大规模光谱巡天测量项目，需要更小尺寸和高精度的光纤定位单元。本文提出了R-θ形式光纤定位单元的R机构精定位部分设计方案，通过使用叠堆式压电陶瓷并结合柔性铰链式杠杆位移放大机构，实现了R机构精定位部分的位置精度。为了尽量减小迟滞非线性对精定位精度的影响，采用经典的Preisach模型建立了放大后输出位移的驱动模型，并在此基础上进行了相应的优化。最终建立的精定位位移模型的平均误差在4μm以内，相比于最大40μm的非线性误差，误差得到了大幅度下降。实验结果表明，通过Preisach模型所建立的位移模型进一步提高了精定位的定位精度，满足了精定位的误差设计需求，同时也为后期粗定位留下了更大的设计空间。更多还原

【Abstract】 Next generation large-scale spectroscopic survey projects may require smaller and high-precision fiber-positioning units. In this paper,a design scheme of the precise positioning part of the R mechanism of an R-θ fiber-positioning unit is proposed. Stacked piezoelectric ceramics combined with a flexible hinge lever displacement amplifying mechanism are used to achieve positional accuracy of the precise positioning part of the R mechanism. To minimize the influence of hysteresis nonlinearity on the precision of precise positioning,the classical Preisach model is used to establish the driving model of the amplified output displacement,and the corresponding optimization is conducted on this basis. The average error of the final established precise positioning displacement model is within 4 μm,and this error is significantly reduced compared with the maximum nonlinear error of 40 μm. The experimental results reveal that the displacement-driven model established by the Preisach model further improves the positioning accuracy and meets the error design requirements of precision positioning and also allows for a larger design space for later coarse positioning.更多还原