Analysis of the Design and Use of Ultrasonic Range Finder
Data Measurement and Analysis
Due to the limitations of the actual measurement work, six distances of 30cm, 50cm, 70cm, 80cm, 90cm, and 100cm below one meter were selected for measurement, and each distance was measured seven times continuously to obtain the measurement data (temperature: 29°C), as shown in the table. It can be seen from the data in the table that the measured value is generally a few centimeters larger than the actual value, but the accuracy of continuous measurement is relatively high.
For each set of measured data, remove a maximum value and a minimum value, and then calculate the average value, which is used as the final measurement data, and finally comparative analysis is carried out. This processing of data also has a certain degree of science and rationality. From the data in the table, although the temperature compensation has been carried out on the ultrasonic wave, the relative error is relatively large in the measurement of a relatively short distance. Especially for the distance measurement of 30cm and 50cm, the relative errors reached 5% and 4.8% respectively. But from all the measurement results, the error of this design is relatively small and relatively stable. The blind area of this design is about 22.6cm, which basically meets the design requirements.
Error Analysis
The ranging error mainly comes from the following aspects:
(1) There is a certain angle between the ultrasonic transmitting and receiving probe and the measured point, which directly affects the maximum value of the measuring distance;
(2) The sound intensity of the ultrasonic echo is directly related to the distance to be measured, so the actual measurement is not necessarily triggered by the zero-crossing point of the first echo;
(3) Due to the crude tools, the actual measurement distance also has errors. There are many factors that affect the measurement error, including field environment interference, time base pulse frequency and so on.
Application Analysis
The use of ultrasound to measure the ground distance in the atmosphere is a technology that has been formally applied only after the development of modern electronic technology. Since ultrasonic ranging is a non-contact detection technology, it is not affected by light, the color of the measured object, etc., and can be used in harsh environments. (such as containing dust) has a certain adaptability. Therefore, it is extremely versatile. For example: surveying and mapping topographic maps, building houses, bridges, roads, digging mines, oil wells, etc., the method of using ultrasonic waves to measure ground distances is realized using photoelectric technology. Low, labor-saving, easy to operate.
Ultrasonic rangefinders are also used in advanced robot technology. The ultrasonic source is installed on the robot, which continuously emits ultrasonic waves to the surroundings and simultaneously receives echoes reflected by obstacles to determine the robot's own position, and uses it as a sensor to control the robot. computer and so on. Because ultrasonic waves are easy to directional emission, good directionality, and easy control of intensity, its application value has been widely valued.
In a word, it can be seen from the above analysis that using ultrasonic ranging has many advantages in many aspects. Therefore, the research of this topic is very practical and commercially valuable.
