%0 Journal Article %T 风洞天平校准台并联复位机构精度分析<br>Accuracy of the parallel reset mechanism in a wind tunnel balance calibration system %A 关立文 %A 陈晃 %A 付萌 %J 清华大学学报(自然科学版) %D 2018 %R 10.16511/j.cnki.qhdxxb.2018.25.011 %X 并联机构由于具有结构简单和高刚度等优点,被大量应用于工程领域,该文针对风洞天平校准台6-DOF(degree of freedom)并联复位机构进行精度分析。利用D-H(Denavit-Hartenberg)方法分析每条支链运动传递过程,建立包含铰链制造误差的RRRPRR支链运动学模型。利用Qusai-Newton法分析不同结构参数下铰链制造误差对加载中心精度的影响规律。研究结果表明:加载中心精度与铰链偏移误差处于同一数量级,且呈线性关系;为降低铰链偏移误差对加载中心精度的影响,在满足设计要求的前提下,应选择较小定平台和较大动平台、较小平台铰链夹角以及较大的平台间距离。该研究为高精度风洞天平并联复位机构提供了重要的设计依据。<br>Abstract:A 6-DOF (degree of freedom) parallel machine was used as the reset mechanism in a wind tunnel balance calibration system because of its simple structure and stiffness. A model was developed using the D-H (Denavit-Hartenberg) convention to analyze inaccuracies in the reset mechanism caused by joint manufacturing tolerances. In this model, each closed-loop kinematic chain was treated as a RRRPRR chain. The effects of the joint tolerances and structural parameters on the kinematic accuracy were calculated based on Qusai-Newton method. Simulations indicate that the inaccuracy is on the same order of magnitude as the joint offsets. A principle is given to determine the structural parameters needed to improve the accuracy of this type of reset system. %K 风洞天平 %K 复位机构 %K 精度分析 %K 铰链误差 %K < %K br> %K wind tunnel balance %K reset mechanism %K accuracy analysis %K joint tolerances %U http://jst.tsinghuajournals.com/CN/Y2018/V58/I3/298