【作者】 侯一民；

【导师】 高宗海； 杨农合；

【作者基本信息】 西安理工大学 ， 测试计量技术及仪器， 2003， 硕士

【摘要】 指针式仪表是一种在工业中广泛应用的仪表，其种类繁多，例如：百分表、千分表、汽车航空仪表等。这些仪表因其操作简便、生产成本低，深受用户的欢迎。但是，指针式仪表也需要在出厂或者经过一段时间的使用之后进行检定，以确定其是否合格。传统上的检定是靠手工操作，通过人眼来识别读数并计算误差的。而这种方法有很多弊端，如：人眼检定对精度的影响较大、检定效率较低等等。因此，需要找出一种具有合适的精度且效率较高的检定方法。 本论文中，采用了基于计算机视觉技术的检测方法，分析了指针式仪表的表盘特征，设计了表盘指针提取的方案，通过图象处理理论设计系统软件。运用CMOS摄象头以及Windows系统函数实现表盘图象的实时采集，运用步进电机控制仪表指针转动。将图象采集，表盘指针驱动技术与图象处理技术相结合，设计了整套的实时表盘读数、误差比较、检定系统。运用Visual C++编写了软件。最终实现了对指针式仪表的实时检定。 在精密测量中采用计算机视觉以及图象处理技术是一种比较新的方法，它拥有其他方法所不具有的优点：检定精度、效率都较高。在未来的生产实践中，这种方法必定有更加广阔的应用前景。更多还原

【Abstract】 As one of the measurement instruments, the gauge with pointer is generally used in the manufacturing process at present. There are many kinks of gauge with pointer including pressure gauge, dial gauge, micrometer gauge, automobile gauge and so on. Because they are convenient for use and have low costs, they are popularly used by people. But they also had to be tested after being made or used for a long time so that to insure they are eligible. Traditionally, the gauges are tested by human eyes. However, some of the subjective factors such as: observation angle, observation distance and fatigue may have effects on the value. This method will lead to not only gross error and small reliability but also low efficiency and body fatigue.In this paper, aimed to this laggard condition, the author used the method based on computer vision technology to test the gauges, analyzed the gauges’ characters and designed the blue print to pick-up the pointer. The pointer was droved by step motor witch was been controlled though PC parallel port and the images were captured by a CMOS camera. The program was wrote by visual C++ and the testing was realized finally.The computer vision and image processing technology being used in the exact measurement is a new method, and it has many good points such as: high precision and efficiency. This method will be widely used in the future.更多还原