Research And Design Of Portable X-ray Stress Meter Control System

In the process of material production,uneven plastic deformation,temperature change and phase transformation will leave residual stress to the material,and the existence of residual stress has a significant impact on the service life of the material.By weakening harmful residual stress or increasing beneficial residual stress,the service life of the material can be effectively improved,the possibility of early cracking of the material can be reduced,and the occurrence of unexpected situations can be avoided.Therefore,it is very important to accurately measure the residual stress of materials,and the common instrument for detecting residual stress is X-ray stress meter.At present,the domestic stress meter equipment is not highly intelligent,the measurement accuracy cannot be compared with foreign products,and the products are large in size,inconvenient to carry,and not suitable for use in outdoor environments such as construction sites and fields.As a large manufacturing country,my country also has the need for stress testing in many outdoor environments.Therefore,in order to make up for this gap,it is very meaningful to develop an X-ray stress instrument with high stability,high safety,high precision and easy portability.In this paper,the research background and importance of the stress gauge are firstly described.Then,after the in-depth analysis of the requirements of the entire stress gauge control system,a control system scheme based on ARM and CPLD processor architecture is proposed.,and on the basis of analysis and research,it is further proved that the scheme is feasible.In the specific work,first of all,with ARM and CPLD as the core processors,the functions of each part of the system,chip selection,peripheral circuits and corresponding schematic design are introduced in detail.After the hardware circuit of the system is built,the software programming of each sub-module is introduced.ARM is mainly responsible for receiving and parsing the commands sent by the host computer,and controlling the normal operation of the four motors.In order to make the motion process of the motors more stable and smooth,a motor trapezoidal acceleration and deceleration control algorithm is introduced,and the calculation formula of the algorithm is deduced.,and the corresponding software implementation scheme is given.The CPLD is mainly responsible for counting the pulse intensities of the two X-ray detectors.After the CPLD count is completed,the data is sent to the ARM,the ARM processes the data,and then forwards it to the upper computer.After the upper computer receives the data,the stress value of the test point is calculated according to the relevant algorithm.Among them,in order to improve the use efficiency of the CPU and ensure the real-time and reliability of the system,in this paper,the FreeRTOS embedded operating system is transplanted into the stress gauge control system,and based on FreeRTOS,7 tasks are established,each task Cooperate with each other to complete the requirements of the system together.After the hardware objects and software programs of the system are made,the function of the whole set of equipment is tested.Taking the standard sample 403 steel and unstressed iron powder as the test object,its stress value is tested,and the final result is within the error range,which proves that the system can meet the design requirements and meet the expected functions.