【作者】 罗中兴；

【导师】 魏毅立；

【作者基本信息】 内蒙古科技大学 ， 控制理论与控制工程， 2009， 硕士

【摘要】 软测量技术刚刚兴起,利用超声波进行风速风标测量的系统现如今还不成熟,许多问题有待解决。当超声波在空气中传播时,由于受到风速的影响,顺风和逆风的情况下会产生一个可以测量的时间差。因此,基于这个原理制成的时差法超声波风速测量仪表,具有精度高、可靠性强、集成度高等优点。超声波风速风标仪表与传统的机械式仪表、电磁式仪表相比,具有安装简单、维护方便,不需要考虑机械磨损、精度较高,不需要人为的参与、并且可完全智能化的优势。TMS320F2812作为32位的微处理器,具有丰富的片上资源,高达150M的系统时钟,而且功耗很小,适合作为智能仪表的核心处理器。本文研究了基于TMS320F2812的风速风标测量系统,可以实现风速的测量、风向的辨别、显示以及与上位机之间的通信等功能。系统硬件电路采用模块化进行设计,这种思想大大简化了系统硬件电路设计的复杂性,增强了系统的稳定性与可靠性。系统硬件电路包括超声波的发射模块、超声波的接收模块、显示模块以及与上位机通信模块。另外,根据超声波信号的特点,选用CX20106集成电路,在准确判断超声波到达时间的问题上有所改进。系统软件设计采用了模块化设计方法,增强了软件的可移植性、可读性和稳定性。软件采用C语言与汇编语言混合编程。C语言具有编程简单,可以移植等优点,但是产生代码较长,对硬件的直接控制能力相对较弱;汇编语言产生的代码较小,控制硬件灵活,但是可读性差,移植困难,因此为了发挥各自优点,产生高速度、高效率的代码混合编程是最好的选择。文章最后进行了对比实验和误差分析进而得出结论。更多还原

【Abstract】 There are many advantages when ultrasonic is utilized to measure the velocity and vane of the wind. The ultrasonic velocity, influenced by the wind speed, could show a measurable difference when it transmits in the direction of forward flow or in the opposite flow. An ultrasonic anemometer and vane based on the theory was developed, with the superiorities of high precision, high dependability and high integration. Possessing the merits of simple installation, easy maintenance, no mechanical wear, high precision, no participation of man and complete intellectualization, compared to traditional mechanical or electromagnetic instrumentations. The proficient technique has not been widely used in related scale. There are many problems to be researched.TMS320F2812 is a 32bit microprocessor with abundant on-chip resources, and its handling capacity is up to 150M with low power consumption. It is suitable to make up an intelligent instrumentation. Therefore, the ultrasonic wind velocity and vane measurement system based on TMS320F2812 was researched in this study. The multiple variables including wind velocity and vane detection, display and communicate with PC by serial interface were discussed.The system hardware was modularly designed, and as a result, the complexity of complicacy system hardware design was predigested, while the system stabilization and reliability were enhanced. Considering the characteristics of ultrasonic signals, CX20106 was chosen to determine the arrival time of ultrasonic signals.The system software was modularly designed as well, and its portability, readability and stabilization were developed. Software was programmed by a mixing of both C language and assembly language. C language has the advantages of simple programming and good portability, however, the code generated is relatively longer, and the control power to hardware is not so satisfied. On the other hand, assembly language is just of the opposite quality: shorter code, better control to hardware, yet the programming are complex. In order to integrate the virtues of C and assembler language, mixed programming is the best way to achieve the goal of high speed and maximum code efficiency.At the end of the thesis, a contrastive experiment was completed and the system error analysis was given. Then a conclusion is drawn.更多还原