【作者】 蔡卫国；

【导师】 李伟；

【作者基本信息】 中国农业大学 ， 农业机械化工程， 2005， 硕士

【摘要】 根据目前国内外种子检测分级方面的现状,对种子检测分级试验台机构和分级自动控制方法进行了研究。研究着重于实时检测分级试验台的机构设计和分级自动控制系统的功能实现,涉及机械设计、计算机技术、自动控制、传感器等众多技术领域。 本研究确定种子精选分级试验台的主体机构呈梯形,由落种机构、输送机构、图像采集和数据处理单元、精选分级机构、控制系统组成。种子经过落种机构落入传送带上的预制孔穴内,并跟随传送带沿梯形框架运动,当进入视觉采集区域时,摄像头对动态种子图像进行采集,基于形态学信息并结合计算机视觉技术将种子分为4级,最后由精选分级机构对种子实施分级。 本研究选择可编程控制器PLC来实现对整个试验台的控制,由色标传感器对种子位置进行实时跟踪,快速、准确地获得运动中每一粒种子的位置信息,通过电磁阀控制高压气流的通断,将种子按其级别信息吹入相应的容器里, 研究还包括PC机与可编程控制器PLC之间的通讯功能的实现。 最后对研究的结果进行了试验性验证,当传送带速度为0.2m/s,气压为0.8MPa时,种子分级合格率可达90%以上,此时系统处理速度为15粒/秒。实验结果表明:该试验台整体设计方案可行,达到了对种子进行动态实时检测分级的目的和要求,并且进一步优化系统结构后可以产业化推广。更多还原

【Abstract】 According the actuality of seeds detecting and grading in the world , this dissertation focused on the research of a real time seeds accurate grading test-bed framework and control method , which mainly included the design of a test-bed framework and the realization of automatic control functions. Numerous fields are involved in this study , such as machine design, computer technique, automatic control theory , Sensor, and so on .A real-time seeds quality detecting and grading system is designed , the whole test-bed presents trapezium structure in front, which include falling organ, feeding framework, image gathering and data disposing unit, accurate grading cell and control system. Seeds trop into the hole on the strap through the feeding device, and move along the trapezium framework following the strap. When entering into image gathering area, the seeds are photographed . Seeds are sorted into four grades based on the morphologic information and computer vision technique. Finally, the classification mission is accomplished by accurate grading cell.The control of the whole test-bed is completed by a Programmable Logic Controller. The place of seeds are tracked by the sensor, it can obtain position of any seeds fleetly and exactly. The open or close of high-pressure airflow is controlled by the magnetic valve, which blow the seeds into the container according its grade information .The software for the communication from PC to PLC was compiled , which was based on Visual C++ , it was proved to be effective and friendly to operation .At the end of this dissertation , the test-bed was tested . when the strap velocity is about to 0.2m/s and air pressure is 0.8Mpa , the eligible grading ratio of seeds are higher than 90% , the velocity of processing is about to fifteen granule per second . The experiments show that the whole scheme is feasible , the test-bed fulfils the purpose and demand for seeds detecting and grading . If the test-bed is farther optimized , it can be generalized to the industrialization .更多还原