Research And Design Of High Precision Capacitor Heightening System For Laser Cutting

Since the birth of the laser machine,laser cutting technology has been a research hotspot at home and abroad.With the rapid development of Chinese manufacturing industry,laser cutting machine as an important equipment for processing and manufacturing has been widely used in automobile,ship,aerospace and other fields.The technology of height trace for laser cutting is a key technology to improve the quality of laser cutting.This technology improves the quality of cutting by adjusting the distance between the nozzle of laser head and the metal plate to make the laser focus always focus on the best position of the plate.The key technology is the acquisition and transmission of micro capacitance data in the complex and strong electromagnetic interference industrial environment,and this technology has been in the hands of a few foreign enterprises for a long time,which will greatly limit the development of domestic laser cutting equipment.For the above problems,this paper studies the key technology of height trace system for laser cutting.A capacitor preamplifier and the main control board based on ARM+FPGA structure are designed.Firstly,the factors affecting the measurement accuracy of capacitance sensor are analyzed,and a capacitance detection module based on LC frequency modulation circuit is proposed.Secondly,the main control board of capacitance adjustment based on FPGA+STM32 architecture is designed.The main control board has two working modes,namely the independent capacitance adjustment mode and the bus-type capacitance adjustment mode.These two modes can make the device manufacturer use this sensor more flexibly to adapt to different requirements.In independent control mode,Frequency measurement module based on the FPGA collect the signal and then the FPGA will transmit the data to STM32 MCU by SPI bus,finally STM32 MCU will control the Z Axis motor,so that the laser always focus on the right place.In the bus capacitive raised mode,EtherMac real-time IP core integrated in FPGA chip and it can serve as a EtherMac communication network will be collected from the node capacitance FM data via a standard RJ45 interface transmission to the numerical control system,location information is calculated from numerical control system and the numerical control system will control the Z axis motor.The capacitance heightening system has been tested in the simulated working environment in the laboratory,and its measuring effect is good and it can meet the requirements of production and processing.This paper provides an important basis for the design of capacitance heightening system for laser cutting,and has important reference value for the research of microcapacitance information acquisition sensor for industrial control environment.