Ultrasonic flaw detector is one of the important ways of industrial manufacturing and modern inspection. It is widely used in quality inspection and product inspection. By using its products, the risk of defective products can be effectively reduced. Although with the development of electronic technology, some digital ultrasonic testing instruments have appeared in China, but their data processing and expansion capabilities are limited, and they lack sufficient flexibility. The design of ultrasonic testing technology is based on the hardware composition, software design and anti-interference measures of the intelligent system of ultrasonic flaw detector developed by AT89C52 single-chip microcomputer . A good digital ultrasonic testing platform has been developed with the pulse reflection ultrasonic flaw detector as the representative. The system has Measurement, digital display, A/D conversion and other functions , and has the advantages of stable work and good performance. It has laid a good foundation for further and more in-depth research on ultrasonic digital signal processing in the future.
Ultrasonic testing is one of the main technologies of non-destructive testing, and has been widely used in online quality control, safety testing of in-service equipment and key components. As the carrier of ultrasonic testing technology, ultrasonic flaw detector has important research significance in ultrasonic testing. In order to improve the reliability and efficiency of ultrasonic testing, it is an inevitable trend of today's non-destructive testing technology to develop a digital, intelligent, automated, and image-based ultrasonic nondestructive testing system.
This article mainly introduces the design of ultrasonic transmission flaw detector, and first introduces the basic principle of ultrasonic testing, its development history, and current status. Then, the overall design and each functional module of the digital ultrasonic flaw detector in design are discussed, the solution of flaw detector design is determined, and the main control chip and programmable logic control chip in the system solution are selected. Then focus on the hardware design of the digital ultrasonic flaw detector system, including the design and implementation of ultrasonic transmitting circuit, receiving circuit, signal conditioning circuit and data acquisition and processing system. Finally, the software design of the digital ultrasonic nondestructive flaw detector system is introduced, and the overall process of system software design, generation of ultrasonic excitation pulse signal, logic control of data acquisition system and data processing of echo signal are introduced.
Keywords : non-destructive testing; ultrasonic flaw detection; AT89C52; signal conditioning, high-speed data acquisition
Abstract
Ultrasonic nondestructive testing is one of the most widely used nondestructive testing methods in modern industrial production. It is of great significance to improve the quality and reliability of products.With the development of electronic technology, some digital ultrasonic testing instruments have appeared in China, but their data processing and expansion capabilities are limited and they lack sufficient flexibility.Ultrasonic testing technology, the design of ultrasonic flaw detector intelligent system based on AT89C52 single chip microcomputer development hardware composition, software design and anti-interference measures, represented by the pulse reflection type ultrasonic flaw detector was developed to complete A good platform for the digital ultrasonic testing, the system has measurement, digital display, A/D conversion, and other functions, and has the advantages of working stability, good performance.It lays a good foundation for further research on ultrasonic digital signal processing.
Ultrasonic testing is one of the main techniques of nondestructive testing. It has been widely used in online quality control, in-service equipment and safety testing of key parts.As the carrier of ultrasonic testing technology, ultrasonic flaw detector has important research significance in ultrasonic testing.In order to improve the reliability and efficiency of ultrasonic testing, it is an inevitable trend to develop a digital, intelligent, automatic and pictorial ultrasonic nondestructive testing system.
This paper mainly introduces the design of ultrasonic transmissive flaw detector, first introduces the basic principle of ultrasonic testing and its development history and present situation.Then, the overall design and functional modules of the digital ultrasonic flaw detector are discussed, the design solution of the flaw detector is determined, and the main control chip and the programmable logic control chip in the system solution are selected.Then the hardware design of the digital ultrasonic flaw detector system was studied, including the design and implementation of the transmitting circuit, the receiving circuit, the signal conditioning circuit and the data acquisition and processing system.Finally, the software design of digital ultrasonic nondestructive flaw detector system is introduced, and the overall process of system software design, the generation of ultrasonic excitation pulse signal, the logic control of data acquisition system and the data processing of echo signal are introduced.
Keywords: Nondestructive testing;Ultrasonic testing;AT89C52.Signal conditioning, high-speed data acquisition
Chapter 1 Introduction
1.1 Research purpose and significance
Ultrasonic flaw detection technology is currently a relatively advanced and widely used detection technology. It is widely used in product quality inspection and can effectively reduce the defective rate of products. When we detect whether a material or product is damaged, we can use the changes in the process of sound and light to detect whether there is a defect inside the material according to its internal structural characteristics, and finally we can confirm the part where the defect occurs.
In this final study, the study is mainly aimed at the direction of the control system of the intelligent ultrasonic flaw detector. The main controller of the intelligent ultrasonic flaw detector control system is the AT89C52 single-chip microcomputer using Flash memory. Several sensors are used to collect data and then transmitted to the single-chip microcomputer. Mode conversion, data display and other functions can realize intelligent and accurate control of ultrasonic flaw detector. The main control part of the circuit is mainly composed of control circuit, data conversion circuit, signal acquisition circuit, display circuit, etc., so as to meet the design requirements, and improve the operator's quickness on the basis of convenience for the operator.
Ultrasonic flaw detector is the most important measuring equipment in the current market. Accuracy and rapidity have gradually become the display requirements of intelligent ultrasonic flaw detector. It is more convenient for users to monitor and measure in real time, so as to effectively eliminate the relatively backward mechanical flaw detectors in the market. At the same time, it has gradually become a leader in the ultrasonic flaw detector industry. In this intelligent ultrasonic flaw detector design and development project, programming is mainly used for software development, with the embedded development system as the core, and the hardware circuit mainly uses ADC0809 digital-to-analog converter, which has high precision. However, since the sensor collects the signal and outputs an analog voltage value, it needs to be converted into a digital voltage signal that the embedded development system can recognize, and then it is further processed, and the data is presented on the LCD display Come out, the design cost is relatively low, and can meet the actual demand. The advantages of the intelligent ultrasonic flaw detector design are mainly reflected in the following points: 1. Meet the real-time measurement and storage of data; 2. The upper limit value can be modified or reset; 3. The measurement accuracy is relatively high; 4. Data transmission display High speed and high accuracy.
Because ultrasonic is widely used, different probes are needed in different occasions, and the processing and control of ultrasonic signals are different. Therefore, a certain type of non-destructive testing equipment is usually only suitable for one or several applications. occasion. In order to make ultrasonic flaw detection equipment have better application range, higher processing algorithm and faster update cycle, virtual ultrasonic non-destructive flaw detection equipment can be used. We collect and measure signals according to the input and output of sensors in the system, and then transmit them to the single-chip microcomputer system for signal processing, so as to realize the ultrasonic flaw detection system. The system is the product of the combination of virtual instrument technology and traditional ultrasonic flaw detection system.
Nowadays, foreign ultrasonic detection technology is relatively advanced, using advanced computer technology, information and image processing and other advanced methods, based on the use of these methods, it has been possible to maximize the excavation from the measured object. useful information. We can use many kinds of intelligent control methods, such as artificial intelligence, fuzzy control algorithm, etc., so that it can clearly and accurately detect whether there is a defect inside the product, judge its position, size and nature, and use the echo method to detect the workpiece For scanning, the echo data is stored in the computer, and the performance and quality of the tested product are analyzed and the results are given.
In this final research, the study is mainly aimed at the direction of the intelligent flaw detector control system. The main controller of the intelligent flaw detector control system is the AT89C52 single-chip microcomputer using Flash memory. Several sensors are used to collect data and then transmitted to the single-chip microcomputer. The single-chip microcomputer analyzes and processes the data to meet the needs of ultrasonic flaw detection. To control the intelligence and accuracy of the flaw detector. The main control part of the circuit is mainly composed of clock circuit, data conversion circuit, reset circuit, alarm circuit, signal acquisition circuit, etc., so as to meet the design requirements, and improve the operator's quickness on the basis of convenience for operators.
Flaw detector is the most important measuring equipment in the current market. Accuracy and rapidity have gradually become the display requirements of intelligent flaw detectors. It is more convenient for users to monitor and measure in real time, so as to effectively replace the relatively backward mechanical measuring devices in the market. , and gradually become the leader in the flaw detector industry.