Design Of Automobile Parts Detection Terminal Based On LVDT

With the fast development of the automobile industry,the demand for auto parts related to automobiles has also shown an exponential growth.Precision detection is a key factor affecting the quality of parts.At present,there is little research on workshop automation testing terminals in China,especially on low-cost universal open testing terminals,which lack of in-depth research.In the survey,it is found that the small and medium-sized parts enterprises have two main problems: it is difficult to popularize the expensive special testing equipment;Some production lines still adopt manual measurement and third-party sampling to cope with factory testing.In this way,it will be difficult to master the accuracy of its own products,resulting in low measurement efficiency and long delivery cycle,making the enterprise at a disadvantage in the market competition.In view of the above problems,this paper designs a set of automotive parts detection terminal system based on LVDT(linear variable differential transformer).The system uses multiple acquisition cards to communicate wirelessly with the terminal,which can monitor data in real time and has functions such as data calculation,storage and traceability.After the system terminal is installed on the corresponding component test bench,it can realize the rapid,multi-functional and high-accuracy detection of the components.The main contents of this topic are:(1)In-depth study of the working principle of LVDT,starting from the generation of magnetic field,the transformation relationship between moving iron displacement and output signal,established the LVDT mathematical model,LVDT measurement model and measurement flatness error model,and derived the corresponding expression.The measurement plane is demonstrated,the selection of the probe material is analyzed,and the feasibility of the scheme is verified theoretically.(2)The design of the detection terminal was completed according to the actual problem and design requirements.The LVDT-based automotive component inspection terminal includes the hardware design and software design of the acquisition unit and the core board.The system mainly includes a signal conditioning module,a data processing module,and a data traceability module.Based on Qt,a set of terminal detection software was developed,which is combined with visual color interface for real-time display,which is convenient for human-computer interaction.The whole set of equipment can measure the product,perform mathematical calculation on the result,judge the qualified or not of the product in time,trace and store the measured data.(3)After the system software and hardware are coordinated,the entire system is tested for acceptance with the gantry.The test object selected the brake pad and tested its flatness for 10 times.The flatness was evaluated according to the optimized least square algorithm.The comparison of third-party test results showed that the system error was small and the testing system had good stability.