【作者】 魏霖；

【导师】 王从军；

【作者基本信息】 华中科技大学 ， 材料加工工程， 2006， 硕士

【摘要】 反求工程作为一种新型的设计方法,在引进国内外的先进制造技术、缩短产品的开发周期以及降低生产成本等方面发挥着重大的作用。关节式坐标测量机由于其体积小、重量轻、携带方便、测量范围不受工作台面限制等优点,已日益受到逆向工程领域的重视。本文在前人工作的基础上,对新开发的关节式坐标测量机的数学模型和参数标定进行了以下几方面的研究。首先论述了关节式坐标测量机的系统机械结构设计,并在Denavit-Hartenberg方法的基础上,建立了关节臂的数学模型和测量运动方程,对机构的坐标转换方程进行深入的推理和验证;同时用Matlab软件做仿真试验,模拟出系统的相应位姿,从而精确、直观地验证了数学模型的正确性。其次建立了关节臂的误差模型,通过误差模型实验,证明了参数误差模型的真实、可靠;设计一种全新的标定块,运用矩阵全微分方法分析误差,利用最小二乘法和迭代法快速、高精度地实现了关节臂的结构参数和运动参数标定,预计精度可达到亚像素级。最后设计了关节臂参数与坐标变换标定软件模块,即数据记录、标定计算和测量模块。运用Visual C++6.0和Matlab7.0混合编程,具有良好的实用性和通用性;在Pro/MECHANICA模块中实现了ACMM的运动分析和模拟仿真,更清晰、逼真地再现了机构运动的情况,同时可获得几何图元速度、加速度以及机构运动的轨迹曲线,以及判断元件间的干涉情况。更多还原

【Abstract】 Reverse Engineering (RE) as a new designing method can do a lot of things in the absorption domestic and international advanced technique, shortening the product’s development period and lowering the production cost. Nowadays articulated coordinate measuring machine(ACMM) is becoming more and more popular in the field of RE and gained great interest from the field of RE, because of its a lot of advantages such as convenience to be used, portability to be carried for its small volume and light weight and flexibility to the worktable. Based on a series of previous researches in this field, a lot of researches on mathematical module and parameter calibration based on newly developed ACMM were carried out as follow in this dissertation.Firstly, the systematic mechanical design about the links and joints for Articulated Coordinate Measuring Machine is discussed. On the basis of D-H method, the mathematical module and movement equation for probing the joint arm end were built; the coordinate transformation equations of the machine were thoroughly inferred and validated. And the verification method was used to simulate the experiment results with the powerful mathematical tool——MATLAB, and therefore the position and posture were simulated. The good agreement of numerical simulation with those of corresponding indicated that the developed model was reasonable and feasible.Secondly, the error model of joints was established, the parameters of joints error were within the extent of permission. The error model was therefore proved true and reliable. Furthermore a new calibration block for calibration was designed. By the aid of a series of analysis with exact differential matrix and least squares method equations, calibration of the structure with high precision was achieved. And the accuracy is expected to reach sub-pixel degree.Finally the articulate arm parameters and coordinate transformation calibration software modules, three independent module—the data recording, calibration calculation and measurement were designed. Compiled with Matlab7.0 and Visual C+ + 6.0, the practicality and universality of the software modules were good. Kinematic analysis and simulation experiment could be realized clearly and vividly in the Pro/MECHANICA module. Simultaneous the rate, geometric acceleration and movement traces of the machine could be also achieved in ACMM, furthermore the interference between components can be judged.更多还原