关节臂式坐标测量机最佳测量的关键理论与技术研究

The articulated arm coordinate measuring machines (AACMM) have many merits of nimble use ,convenient carry and so on, thus they are highly thought of by people. But their fabricating cost is expensive and their measuring precision isn't high, so they are restricted on widespread use. The study on AACMM's precision guarantee measures is mainly focus on hardware,structure and calibration, but the deep cause is less considered at home and abroad. The optimal measurement is centred on and spread on the project. The spatial error model is researched. The whole working space's error distribution map is drawn. And then the optimal measurement area is got. When the measured workpiece is placed within it, the optimal measurement is realized. The problem on one AACMM with many measurement models is discussed. Different areas have diverse measurement models, so the measurement results can be compensated in the different extents. The probe parameters calibration software is developed. It is conveniently manipulated by users and can be assured with measuring precision on the spot. Finally the AACMM with new achievements is developed. And thus high precision measurement is realized on the basis of lowcost.The research results go far beyond the articulated arm coordinate measuring machines and help to guide other type coordinate measuring machines.

关节臂式坐标测量机具有使用灵活、携带方便等诸多优点，深受业界人士的好评，但因其制造成本昂贵且测量精度不高，从而在普及应用上受到了限制。国内外对关臂节式坐标测量机精度保证措施的研究主要集中在硬件、结构、标定等方面，而对影响精度的深层次原因研究较少。本项目围绕测量机最佳测量这一关键问题而展开，研究测量机的空间误差数学模型，绘制整个工作空间的误差分布图，找出最佳测量区，当被测工件置于最佳测量区时，可实现最佳测量；研究一台关节臂式坐标测量机包含多个测量模型问题，不同区域具有不同测量模型，使其具有不同程度的误差补偿，最终实现最佳测量；开发方便用户操作的测头参数标定软件，从而在现场使用过程中保证测量精度；最后，研制一台新成果关节臂式坐标测量机，使其在较低成本的基础上实现高精度测量。本项目的研究成果不仅仅局限于关节臂式类坐标测量机，对其它类型的坐标测量机也有指导作用。

关节臂式坐标测量机是一款整合了机械、电子、自动控制、计算机信息等先进技术为一体的高精密测量仪器，是需要不断集成创新的高科技产品。项目围绕测量机最佳测量这一关键问题而展开，研究了测量机的最佳测量区、“一机多模”和圆光栅偏心误差等理论，同时开发了多测量模型自动转换和测头参数标定等软件，有效地提高了测量机的测量精度。.（1）研究了关节臂式坐标测量机最佳测量区问题，验证了最佳测量区的存在，运用支持向量机方法建立了空间误差分布模型，讨论了基于单点测量和空间距离测量的最佳测量区。.（2）采用在不同区域标定测量模型的结构参数方法构建了多测量模型，并以一台测量范围R=1200mm的关节臂式坐标测量机进行了实验，规划了9个子区域，实现了多测量模型转换功能。.（3）研究了圆光栅编码器偏心误差影响坐标测量机测量精度的问题，用MATLAB软件中的非线性最小二乘拟合函数nlinfit 获得了6个圆光栅偏心误差模型的参数，构建了包含圆光栅编码器偏心误差的测量模型。.（4）对坐标测量机测头参数θ60，l6，d6进行了分析，构建了只含测头参数的测量模型，选用锥窝标准件进行了测头参数标定实验，并设计了一款方便用户操作的测头参数标定软件。.本项目的研究成果有助于关节臂式类坐标测量机测量精度的提高，对其它类型的坐标测量机也有指导作用。