基于声表面波传感技术的智能刀具的建模仿真研究机械制造及其自动化专业论文.docx

哈尔滨工业大学工学硕士学位论文 Abstract Surface acoustic wave (SAW) devices are microelectromechanical system that are used for signal processing by manipulating surface waves on piezo-electric substrate through interdigital transducer (IDT). Because of their versatility, small size, and ease of fabrication, they have broad applications ranging from professional radar and communications systems to consumer areas such as TVs, resonators, mobile phones, and sensors. SAW sensor is a new important division of SAW devices, its distinctive advantages of high precision, high resolution, digital output, small mass and size, low power consumption, noise resistance, working in harsh environment make it a promising sensor for various applications. At present, SAW sensor has been widely used in many areas，in this thesis，I use the SAW sensor technology in the area of cutting tool detection and do some basice exploring research. The basic of thesis is the research item of SAW dynamic test. Firstly, we had researched the electrics-resonance-characteristic of SAW. Such as piezoelectric theory and SAW theory, on this basic, it systemically discusses some basic concepts of SAW sensor. It classifies the SAW sensor, analysis the basic theory of each type of SAW sensor and compares the structure and shows some examples of SAW sensor. Then, A delay line type high frequency SAW gas sensor was preliminarily designed, which gave a specific object for the modeling and simulation of SAW sensor and decide the material and the dimension of the sensor. It provided a real model for the simulation of SAW sensor. Some assumptions and simplifications were made for the designed SAW sensor, and basing on these assumptions and simplifications a finite element periodic model of SAW sensor IDT was developed. It compares four types of IDT models and uses Matlab software to program to show the result of design is right for this idea. Finally, in the finite element simulation, by make the two and three dimensio