Design Of Yellow River Flow Velocity Monitoring System

There are many rivers in our country. It is important for the development of our country to make good use of water resource. Hydrographic measurement is becoming more and more important. Flow velocity measurement is one important factor of hydrographic measurement. There have been many mature ways to measure flow velocity. But all of them have different disadvantages.Water in Yellow River is rich in sand and its flow is different in different seasons. So there are many problems in daily work at Luokou Yellow River hydrometric station. Thinking of all these factors, a way based on dynamics balance theory is put forward in this thesis. To analyse the strength brought on a ball in the water, a mathmatics module is found. Then the flow velocity is computed through the mathmatics module. In this way the devices do not need to be cleared as in traditional ways. At the same time, flow velocity of different points can be measured at one time with the new system. Boats for measurement are not needed any more. It needs fewer workers and costs less money than tradistional ways. And it is safer for the workers.In hardware scheme, coordinator and end device are designed based on MCU MSP430F1612 and wireless transmission chip CC2420. Three-axis accelerometer MMA7260Q is used to get obliquity. When designing PCB, 2.4GHz high-frequency design specifications are studied. In order to suppress noise and improve communication quality, components layout and RF antenna design are fully taken into account. In software design, coordinator program and end device program are programmed under IAR Embedded Workbench V3 IDE. A star network is realized based on ZigBee protocol. PC software is developed under PowerBuilder 11.0. Data is transmitted to PC from coordinator through RS232. And then it is stored in database SQL Server 2000. It is convenient to analyse and deal with the data either online or offline in the future work. In software algorithm, signals from the accelerometer are denosed using Wavelet Transform theory. Deviation is reduced after the signal is denoised.A lot of experiments are done and a great deal of data is acqured. After compar- ing the result with reference from ADV US69M, it is found that the result is fairly exact and the efficiency is higher than traditional ways. So the system basically achieved expected result.