中英文翻译
专业 | 电气工程及其自动化 |
学生姓名 | 孙旺 |
班级 | M电气112 |
田螺姑娘的故事学号 | 1151402228 |
指导教师 | 吴冬春 |
专业系主任 | 顾春雷 |
撰写日期 | 2015年3月13日 |
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电气工程学院什么是高血脂
外文原文
Ultrasonic ranging system design
Publication title: Sensor Review. Bradford: 1993. Vol. 13
ABSTRACT：Ultrasonic ranging technology has wide using worth in many fields，such as the industrial locale，vehicle navigation and sonar engineering．Now it has been ud in level measurement，lf-guided autonomous vehicles, fieldwork robots automotive navigation，air and underwater target detection，identification，location and so on．So there is an important practicing meaning to learn the ranging theory and ways deeply. To improve the precision of the ultrasonic ranging system in hand，satisfy the request of the engineering personnel for the ranging precision，the bound and the usage，a portable ultrasonic ranging system bad on the single chip processor was developed．
Keywords：Ultrasound r，Ranging System，Single Chip Processor
1.电脑如何一键还原Introductive
语法分析With the development of science and technology, the improvement of people's standard of living, speeding up the development and construction of the city. urban drainage system have greatly developed their situation is constantly improving. However, due to historical reasons many unpredictable factors in the synthesis of her time, the city drainage system. In particular drainage system often lags behind urban construction. Therefore, there are often good building excavation has been building facilities to upgrade the drainage system phenomenon. It brought to the city wage, and it is clear to the city wage and drainage culvert in the wage treatment system. comfort is very important to people's lives. Mobile robots designed to clear the drainage culvert and the automatic control system Free wage culvert clear guarantee robot, the robot is designed to clear the culvert wage to the core. Control System is the core component of the development of ultrasonic range finder. Therefore, it is very important to design a good ultrasonic range finder.
2. A principle of ultrasonic distance measurement
2.1 The principle of piezoelectric ultrasonic generator
Piezoelectric ultrasonic generator is the u of piezoelectric crystal resonators to work. Ultrasonic generator, the internal structure as shown, it has two piezoelectric chip and a resonance plate. When it's two plus pul signal, the frequency equal to the intrinsic piezoelectric oscillation frequency chip, the chip will happen piezoelectric resonance, and promote the development of plate vibration resonance, ultrasound is generated. Converly, if the two are not inter-electrode voltage, when the board received ultrasonic resonance, it will be for vibration suppression of piezoelectric chip, the mechanical energy is converted to electrical signals, then it becomes the ultrasonic receiver.
The traditional way to determine the moment of the echo's arrival is bad on thresholding the received signal with a fixed reference. The threshold is chon well above the noi level, whereas the moment of arrival of an echo is defined as the first moment the echo signal surpass that threshold. The intensity of an echo reflecting from
an object strongly depends on the object's nature, size and distance from the nsor. Further, the time interval from the echo's starting point to the moment when it surpass the threshold changes with the intensity of the echo. As a conquence, a considerable error may occur Even two echoes with different intensities arriving exactly at the same time will surpass the threshold at different moments. The stronger one will surpass the threshold earlier than the weaker, so it will be considered as belonging to a nearer object.邂逅吧
趣味运动会图片
2.2The principle of ultrasonic distance measurement
Ultrasonic transmitter in a direction to launch ultrasound, in the moment to launch the beginning of time at the same time, the spread of ultrasound in the air, obstacles on his way to return immediately, the ultrasonic reflected wave received by the receiver immediately stop the clock. Ultrasound in the air as the propagation velocity of 340m / s, according to the timer records the time t, we can calculate the distance between the launch distance barrier (s), that is: s = 340t / 2
虚拟wifi
3.Ultrasonic Ranging System for the Second Circuit Design
闺怨诗 System is characterized by single-chip microcomputer to control the u of ultrasonic transmitter and ultrasonic receiver since the launch from time to time, single-chip lection of 8751, economic-to-u, and the chip has 4K of ROM, to facilitate programming. Circuit schematic diagram shown in Figure 2.
