基于单片机控制的超声测距系统的研究

【作者】 张丹；

【导师】 贺西平；

【作者基本信息】 陕西师范大学 ， 声学， 2008， 硕士

【摘要】 在空气介质中,超声测距传感器因其性能好,价格低廉、使用方便,在现场机器人定位系统、车辆自动导航、车辆安全行驶辅助系统、城市交通管理和高速公路管理监测系统,以及河道、油井和仓库及料位的探测中都有应用。由于超声波传播不易受干扰,能量消耗缓慢,在介质中传播的距离较远,因而超声波经常用于距离的测量,如测距仪和物位测量仪等都可以通过超声波来实现。为此,深入研究超声波的产生与传播规律、开发高性能超声波换能器及其收发电路,对于超声波检测技术的发展具有十分重要的现实意义。本文详细介绍了一种利用单片机设计的软件控制的,由CX20106A、DS18820等集成元件组成硬件电路的超声波非接触式测距系统。该系统以空气中超声波的传播速度为确定条件,利用反射超声波测量待测距离。在本文中,描述了本系统研制的理论基础,概述了超声检测的发展及基本原理;在介绍超声测距系统功能的基础上,提出了系统的总体构成;介绍了超声传感器的原理及特性,研究了超声传感器的发射及接收电路,其中检波接收电路和温度补偿电路分别使用了两款集成芯片,减少了电路之间的相互干扰,减小电噪声。最后利用测距系统进行验证。在论文研究过程中对各部分电路及系统进行了实验,实验表明,各主要波形及技术指标均达到设计要求。该系统具有硬件结构简单、成本低、工作可靠、流程清晰、精度高等优点,并能实现距离的实时显示,在有限范围的距离测量具有较高的精度和可靠性。最后文中分析了误差产生的原因及如何对系统进行完善。更多还原

【Abstract】 The features of the good performance, low cost, easy use are incarnated in the ultrasonic distance measurement sensor. The ultrasonic distance measurement sensor is usually used at the scene robot positioning system, automatic vehicle navigation, the safety of vehicles traveling support system, the urban traffic management and the highway management monitoring system, as well as the detect in rivers, oil wells, storages and materials. The ultrasonic wave transmission is not easy to disturb, its energy consumption is slowly and it can be transmitted distantly in the medium, so it is frequently used in ultrasonic distance measurement. For example, the range finder and the material level finder can be achieved by ultrasonic wave. Therefore, the in-depth study of the generation and transmission law of ultrasonic and the development of high-performance ultrasonic sensor and transmit and receive circuits is of great practical significance in the development of ultrasonic detection technology.An non-contact ultrasonic distance measurement system based on microprocessor is presented, and the software and hardware are introduced in this paper. The integrated chips of CX20106A and DS18B20 are separately used in the detection accepting circuit and in the temperature compensation circuit in the system. The system could measure certain distance with the reflected wave on condition in which the speed of transmitting wave is fixed. This paper generally specifies the theoretical foundation of the system and summarizes the development and fundamental principle of ultrasonic detection. The paper proposes the whole structure of the system by introducing the function of ultrasonic distance measurement. Moreover, it presents the theory and characters of ultrasonic sensor and studies the transmit and receive circuits of the ultrasonic sensor. The integrated chips are separately used in the detection accepting circuit and in the temperature compensation circuit in the system, reducting the mutual disturbance between circuits and the eletrical noise. At last, the result and error analysis of the experiment is presented.The various parts of the circuit and the whole system are tested in the process of the paper researched. It is proved by experiments that the main waveform and technical indexes are achieved the design requirements. The features of the simple hardware, stable operation, distinct programme flow and high accuracy are incarnated in the proposed system. The results can also be displayed in real-time. The design of the system is provided with high accuracy and reliability in the limited range of distance measurement. Finally, the causes of the error are analysised and the improvements of the system are also presented in the paper.更多还原