With the development of intelligent and digital instruments and the deepening of China's reform and opening up policy, in recent years we have introduced a large number of internationally high-level instruments and meters, and the number of imports has also increased year by year. This not only brings a great impact on the design and development of domestic measuring instruments, components, and production processes, but also a huge shock to the design theory and manufacturing methods of China's instruments. In fact, compared with the status of China's instruments and meters , many foreign advanced intelligent instrumentation design methods and theories should be introduced, digested and absorbed first. This article summarizes the following six aspects and briefly discusses them in order to establish domestically, modernize, and intelligentize product design based on the domestic market.
First, pay attention to reliability design
The theory of reliability (Realizability) is widely used in various fields of engineering technology, and its branch, reliability analysis and design, has been valued and applied in the design of advanced intelligent instruments. We must deeply understand that high-level products leaving high reliability as a guarantee are waste products. Foreign advanced intelligent instruments and meters pay great attention to reliability analysis and design in the design stage. Reliability allocation theory is used to distribute the reliability index from the whole system to the component level and component level, so as to ensure the reliability of the entire machine. When the reliability index of a part cannot be met, a redundant design scheme can be used to achieve it. It can be seen from some reliability design flowcharts that parallel redundancy is generally used in instrument design. In high-reliability occasions (reliability R≥0.999), especially in computer control systems, the redundant method is also used.
Foreign intelligent meters not only pay attention to the reliability design of the meter itself, but also have to consider the design of the useability. The reliability of general electronic instrumentation products belongs to the exponential distribution, while the reliability of instruments with many machining parts belongs to the normal distribution, and the actual calculation is not very complicated. China's instrument design should pay attention to this, this is an important key link of product quality.
Focus on maintainability design
Maintenance (Maintainability) includes not only the maintenance of the product in use, but also technical indicators such as the calibration function, debugging function, and maintenance function of the instrument in the production stage. Maintenance must be guaranteed at the design stage. Foreign intelligent instruments and meters have a high degree of maintenance, making them suitable for production debugging and maintenance, including implementation in the design of automatic detection systems. Products designed in this way provide users with great convenience in the measurement and use process.
Third, advanced design methods and methods
The design of foreign intelligent instruments and meters widely uses modern design methods, such as logic analyzers, computer-aided design systems, etc., which can improve the design debugging efficiency by dozens or even hundreds of times. Therefore, China's instrumentation industry should pay attention to and implement the application of CAD / CAM.
Fourth, product serialization and generalization
Foreign instrument manufacturers have done a good job of serializing their products. Almost every type of product has launched a series of products. There are simple to complex functional series; there are low to high measuring range series; there are different series of accessories such as instrument accessories and interfaces. This will bring huge appeal to users, and the benefits will be considerable.
Advanced intelligent instruments and meters are very versatile. This is reflected in the fact that most products have a universal interface system, which can easily interconnect the system and form an automatic test system with the computer. This greatly expands the use and scope of instruments and meters.
V. Simultaneous development of automatic test systems
Most of the new instruments are based on microprocessor (μP) intelligent design. In this way, manual debugging is very difficult and sometimes impossible. Therefore, the automatic test system (ATS) will be developed simultaneously with the development of instrumentation. With the strong technical support of ATS, the mass production of well-designed intelligent instruments can be reliably guaranteed. Large foreign manufacturers of instruments and computers, without exception, are equipped with high-level functions and systems of automatic detection, automatic calibration and online maintenance technology.
Six, complete supporting service facilities
Smart meters are equipped with detailed instructions for use, give a lot of practical operating procedures, and are accompanied by a variety of optional accessories for expanding the scope of application. The design of these accessories must be integrated with the design of the host, and the wearing parts and regular replacement parts of the meter are supplied in a complete set, which makes users feel very convenient. With the development of this "soft science", the intelligence level of the hardware circuits of instruments can be increased rapidly. British manufacturers are a good example in this regard. The British integrated circuit industry is weak, but the instrumentation industry is very advanced. This mainly lies in the use of modern design ideas and schemes to organize the design of instruments composed of imported components. The modernization of China's instrumentation industry should first be the modernization and intelligence of instrumentation design. Only in this way will it enter a virtuous circle, so that the design and production of instruments and meters are based on localization, and the rapid development of China's instruments and meters is promoted.