超声波测沙仪样机的研制

【作者】 金广锋；

【导师】 吕运朋；

【作者基本信息】 郑州大学 ， 测试计量技术及仪器， 2004， 硕士

【摘要】 该系统利用超声波反射法和衰减法的结合—超声波面积比值法，提高了仪表的精度，增强了仪表抗干扰能力，并能通过无线发射技术，能够实现远距离测量与控制，为我国河流、水文水资源观测与预报，提供了有力的工具。 本系统通过双通道频段采集信号，增强了系统对沙粒粒径的识别能力。信号由接收探头传到信号处理电路，经过放大、滤波、检波、采样保持进入A／D转换器。数据读入微处理器后进行分析，利用数字处理技术，判断其幅值大小、相位的变化，由此来判断含沙量的情况。脉冲的发射由CPU控制，可以发送连续超声波和序列脉冲波。 系统提供了“自动方式”和“人工方式”操作，由键盘进行操作。进入“自动方式”后，仪表将自动间断采集数据、处理和显示结果，然后把数据和结果通过串口或者无线通信方式传给上位机；进入“人工方式”后，可人工控制仪表的工作，有目的的采集数据、显示数据和存储结果或进行远距离传输；也可以利用PC机操作界面，进行现场操作，由对话框发出命令，对仪表工作进行控制。根据测量的要求，采用相应的动态画面，能够显示数据和绘制波形。系统包括水下测试点的温度测量、含沙量的测量。 该仪表一旦研制成功后，将具有使用方便，操作快捷、低成本等特点，能取代传统的测沙器具，大大减轻了操作人员的劳动强度，为我国水利建设与河流水文观测提供了重要的工具。 仪表存在一些不足之处，如测量范围不够大、精度不够高等，需要进一步改进和完善，希望今后能在技术细节上不断改进，以适应实际现场测试不断提出的新要求。更多还原

【Abstract】 The system improves the precision of the instrument and improves its resistingcapacity to disturbance by the method of acreage ratio standard of ultrasonic which combines ultrasonic echo and attenuation .It can realize far-distance measure and control by wireless launch technique. It offers a powerful tool for the observation and prediction of rivers and water resource in our country.This system improves the recognizing ability at the dimension of the sand by using two-band frequency to collect signals. The signal accepted by ultrasonic probe passes disposing circuit, magnifying, sieving its waves, passing demodulation, sampling and holding system and then comes into A/D conversion. The CPU reads in the data, then analyzes and judges its value and phase, and then it can estimate how much sand is in the water. The ultrasonic pulse sent is controlled by CPU, The ultrasonic pulse can be sequent and discontinuous.The system offers "automatism" and "manual work" operation that can be selected by the keyboard. The "automatism" can motion automatically, gathering the data, disposing and displaying the result, then send the result to epigyny PC by COM or wirelessly; The "manual work" can be controlled by man. We can collect data, display and save result or send data from long-distance manually. It can also be handled by PC. PC sends order by dialog frame to control the instrument’s work. Following the measurement’s requiring, it introduces active menu, display the data and draw the wave. The system can measure the test point temperature and content of the sandiness in the water.The system is convenient, shortcut handle and low cost. It will replace the tradition apparatus for the sand measurement, lighten the worker labor, and offer important tool for our country’s irrigation works build and river observation.The instrument has several shortcomings, such as the measurement range is not big enough, the precision is not high enough, and it also needs improvement. We hope the technique can be developed step by step. We hope it can meet the new demand of on the spot field-testing.更多还原