Development Of Normal Orientation Measurement System For Automatic Ultrasonic Testing Transducer

Ultrasonic testing is an important method in nondestructive testing.The incidence angle of ultrasonic has a very important impact on the quality of testing.The efficiency and normal incidence consistency of traditional artificial ultrasonic contact method can not meet its detection requirements.Robot automatic ultrasonic testing has the advantages of high efficiency,high precision and multi station testing,which has become the main development trend of testing production in this field.For the casting bearing parts with variable curvature,it is particularly important to find the accurate normal incidence detection of ultrasonic wave,and it is the "best choice" to use the robot automatic search method.According to the working characteristics and actual requirements of the robot automatic ultrasonic transducer normal measurement system,this paper focuses on the automatic detection technology of finding the normal direction of the detected surface.The main contents are as follows:(1)This paper expounds the research background and significance of the normal position and orientation measurement technology of the transducer in the automatic ultrasonic testing of industrial robots,summarizes the research status of the related fields of the normal position and orientation measurement technology of machines at home and abroad,and puts forward the importance of the normal measurement technology to ensure the detection accuracy in the process of automatic ultrasonic testing.On this basis,this paper determines the research ideas and puts forward the main research contents.(2)The overall design of the normal measurement system for automatic ultrasonic testing transducer.Starting with the analysis of system functional requirements,the system is designed to meet the requirements of experiment and use,and then the basic hardware composition and workflow of the system are introduced.It mainly introduces the industrial robots,industrial control computers,end effectors and Chapter 7.Finally,according to the analysis of the functional requirements of the analysis software,the software development environment of the system is introduced.(3)The hardware integration of the transducer normal measurement system for automatic ultrasonic testing is introduced in detail.This paper analyzes the advantages of PLC control robot,then selects the PLC,introduces the main components in the PLC control cabinet,then designs the automatic ultrasonic testing circuit diagram,establishes the communication between the robot and PLC in the automatic ultrasonic testing system,and describes the external automatic control of the robot in detail.(4)Software development of normal direction measurement system for automatic ultrasonic testing transducer.According to the demand analysis of automatic ultrasonic inspection of special-shaped castings,the PLC programs of robot,the seventh axis,data transmission and alarm modules are designed,and the normal detection algorithm and the forward and inverse kinematics of robot are emphatically studied.The algorithm is simulated and verified to prove the accuracy of the algorithm.(5)Automatic ultrasonic testing transducer normal measurement experiment.After calibrating the parameters of the algorithm model,the normal measurement experiment of the automatic ultrasonic testing transducer is carried out,the experimental results are analyzed,and the error is analyzed.It is verified that this method can achieve accurate ultrasonic incidence detection,and meet the requirements that the included angle between the main axis of the ultrasonic testing transducer and the surface normal of the special-shaped casting is less than 0.5 °.