【作者】 马修水；

【导师】 费业泰；

【作者基本信息】 合肥工业大学 ， 精密仪器及机械， 2005， 博士

【摘要】 现代制造业的发展对三坐标测量机提出了更高的测量速度和精度要求,但测量机的动态特性限制了测量机测量速度的提高,其原因是测量机动态误差对测量精度有较大影响。本文以测量机主要动态误差源分析为理论基础,以测量机动态特性分析实验为依据,对测量机在不同速度参数和空间位置时进行动态误差建模研究。并采用软硬件相结合的方法进行动态误差修正,以提高动态测量精度。 在对测量机触发运行模式下的动态特性进行实验研究的基础上,阐明了测量机动态误差的来源和构成。重点研究了测头系统、机体结构、测量系统对测量机动态误差的影响。对于测头系统,研究了测头系统动态瞄准误差的构成,提出等效测头作用直径的概念,分析速度参数对作用直径的影响,建立了理论模型。对于机体结构,研究了机体动态变形产生机理,建立机体结构动态变形与位移误差转换模型,从理论和实验上验证机体动态变形的空间相关性。研究了光栅测量系统光栅栅线刻划误差、光栅副误差、电子系统误差、温度误差,为研发新型的光栅测量系统奠定了基础。 研制高精度动态误差数据采集对比实验系统,用双频激光干涉仪作为高精度的动态测量基准,实时测量在不同速度下测量机各轴的实际位移,并与光栅系统的读数相比较,二者之差为单轴动态误差。根据ISO 230-2标准处理实验数据,分析不同速度下测量机单轴稳定性及轴之间的相关性,实现比现行静态校准方法更精确的动态校准。 按照《测量不确定度表示指南》所确定的框架,使用已被校准工件对测量机测量不确定度评定。同时,基于Monte Canto方法对坐标测量机动态测量不确定度进行评定,与按照动态测量不确定度A类评定和B类评定结果相比较,该方法对动态测量不确定度评定更符合实际情况。 在动态误差源分析、建模的基础上,采用软硬件相结合的方法进行动态误差修正的研究,用2次样条拟合和shape-preserving函数拟合修正动态误差,用二元线性回归建立不同测位与速度变化时测量机综合动态误差模型,以此来修正动态误差。基于二次莫尔条纹原理探讨了纳米测量精度光栅测量标尺,将有可能改善目前光栅信号细分电路延时对测量机动态性能的影响。 基于坐标测量机动态特性的研究成果,对坐标测量机性能评定和精度评定的国际标准和国家标准进行了分析,重点对ISO 10360-2、ISO 10360-5、ISO 15530-2.2进行研究,并就有关技术条款的制定或修订提出建议。更多还原

【Abstract】 Modern manufacturing technology has put forward more exacting demand of speed and accuracy on Coordinate Measuring Machines (CMMs). High speed has become a new trend in CMMs technology. However, with the increase of speed of CMMs, the dynamic characteristic will be limited since dynamic errors will have a great impact on the measuring accuracy and act as a barrier to the measuring cycle time. This paper takes the main dynamic error source analysis on CMMs as the theoretical foundation to make research on dynamic error modeling of CMMs running with different velocity parameter and space position based on the CMMs dynamic characteristic analysis and testing. The method combining software with hardware is used to carry on the dynamic error correction to improve the dynamic measuring accuracy.The process of CMMs dynamic characteristic is studied experimentally under the touch-trigger probing pattern. The main dynamic error sources and composition of CMMs are identified and analyzed in detail. This paper makes research mainly on the influence which the probe system, machine structure and measuring system have on the dynamic error of CMMs. As for the probe system, the composition of its dynamic probing error is studied. A new concept of functional diameter of tip is put forward, the impact of the velocity parameters on the functional diameter is analyzed and the model of functional diameter is set in theory. As for the machine structure, the reason for its dynamic deformation is studied. The conversion between dynamic deformation and displacement error is modeled to validate the place-related characteristics of machine structure dynamic deformation both experimentally and theoretically. As for measuring system, the grating system scribing error, grating pairwise error, electronic system error, temperature error are studied, which pave the way for the development of the new grating measuring system.Develop the high-accuracy dynamic error data gathering contrast experiment system, use the double frequency laser interferometers as the high-accuracy dynamic measuring benchmark and measure the actual displacement of every axis of CMMs under different velocity, in real-time. Comparing the displacement with the reading of grating system, the difference is the single axis dynamic error. According to the ISO 230-2 standard to deal with the data, this paper analyzes the CMMs single axis stability and interrelated characteristic among axis under different velocity to realize the dynamic calibration which is more accurate than the static calibration.The dynamic measurement uncertainty of CMMs is evaluated with calibratedworkpieces according to the framework confirmed by "Guide to the expression of uncertain in measurement". At the same time, the dynamic measurement uncertainty of CMMs is evaluated using Monte Carlo method. By the contrast of the A type and B type evaluation, this method has access to the actual conditions.On the base of dynamic error sources analysis, modeling, the method of combining the software with hardware and the way of square sample stripe fit and shape-preserving function fit are used to make research on the dynamic error correction as weli as the way of setting up CMMs compositive dynamic error model under different measuring position and velocity, adopting dual linear returns. It is possible to smooth the impact of the grating signal subdivision circuit time-delay on the dynamic performance of CMMs when the grating measuring scale with the measuring precision of nanometer is studied based on two times Moire fringe principle.On the base of the research outcome of CMMs dynamic characteristic, this paper analyzes the international standard and national standard of CMMs performance evaluation and precision evaluation, especially ISO 10360-2, ISO 10360-5, ISO 15530-2.2 are studied and give some advices to the establishment or revision of relevant technological clauses.更多还原