Key Technology Research Of Integrated Ultrasonic-imaging Survey About Aviation Components

Nowadays parts of complex surfaces are widely used in many fields such as aviation, shipping, automobile and medicine, and metal rods are one of the most widely used in mechanical engineering.So the problem of improving the accuracy and efficiency of their detection has caused much concern. Therefore, it is of great importance to design an ultrasonic detection system with flexibility, high precision, high efficiency and acceptable cost. On the basis of study on two projects: "10-DOF ultrasonic detection system for complex surfaces part" and "Ultrasonic water-logging automatic survey system for rods", this thesis studies the technologies of ultrasonic measurement, kinematic and dynamic modeling of 10-DOF ultrasonic system, real-time sensitivity auto-adjusting, integrated technology of ultrasonic measurement, surface construction and ultrasonic detection for complex surface parts and rods, thus improving the accuracy and efficiency of ultrasonic detection for parts of complex surfaces. Meanwhile, an auto-detection system for metal rods with rough surfaces and bad columniform accuracy is presented for the first time. The contents include:In Chapter 1, the state-of-the-art of nondestructive testing (NDT) of parts of complex surfaces and metal rods is surveyed, and the significance of the thesis is discussed together with the study of advanced international NDT technologies, and two different atuo-dctection NDT systems for parts of complex surfaces and metal rods are presented.In Chapter 2, an integrated ultrasonic NDT model for parts of complex surfaces is established and its kinematics analysis is provided. Data visualization technology is used in ultrasonic imaging, and software design method and interface of the visulization software is given.Since integrated ultrasonic NDT system for parts of complex surfaces is usually used to detect thin-shell curved surfaces, ultrasonic transmission method is needed. Due to the strict requirements of ultrasonic transmission method, the position of ultrasonic probe should be kept accurately in the process of detection. In Chapter 3, first a group of dynamic formulations is deduced by Newton-Euler approach, then a virtual prototype model with ADAMS is set up, using real size and actual movement parameters of the detection robot. On this basis a simulation is performed for cylindrical surface detection, and force and moment curves are obtained. Finally, methods of error compensation out of robot block are presented, the conditions of position error elimination are deduced, and test of error compensation is carried out.Because parts of complex surfaces to be detected are usually parts with variable thickness, after analyzing the advantages and disadvantages of current sensitivity compensation methods, in Chapter 4, an improved real-time sensitivity adjusting algorithm based on stable amplitude is presented. Auto-detection with sensitivity compensation is implemented, and obtains good results.In Chapter 5, the software, hardware and mechanical parts of integrated ultrasonic NDT system for parts of complex surfaces are introduced, the software design method for the system is presented, inroduction for each module of the software is given, a detection method for columniform part with composite material is proposed, a complete application example is provided for this part, and experimental results of detection is given.Presently most detection systems for rods in China work in traditional manual mode, and most of the auto-detection systems in use cannot meet the demands of rods detection, therefore, in...