Research Of High Precision Measurement Technology In Precipitation Rate Of Salt Spray

The materials in the environment under the action of corrosion are a common phenomenon. The more salt, humid climate environment, the corrosion phenomenon occurs more easily.It is the most important methods that the salt spray test as a measured material the corrosion resistance of is widely used in the world. Fog deposition rates reflect the salt spray corrosion characteristics, is an important parameter in the salt spray test. Need real-time control experiment fog deposition rates in the range of1Φ2mL/80cm2·h. Evaluation of fog deposition rates per unit time is, the volume of brine condensation within the unit area as an index. In this paper, the salt spray interference environment fog deposition rates, high precision automatic measurement technology.In this paper, laser triangulation method of non-contact measurement method based on the theory and technology status of level measurement and control system of fog deposition rates at home and abroad, the brine liquid level line automatic measurement.According to the salt spray test requirements throughout the sedimentation rate consistent requirements, the paper presents a set of multiple subjects’object-oriented level inspection program. Linear motor driven by a set of measuring devices can take advantage of continuous48-hour level of12observation position automatically detect the same time, in order to avoid the salt spray interference detection process, using flexible tube connected to distant level monitoring program, both ensure test accuracy, detection improved operating environment.The liquid level detection exam device has been built. RBF neural network method of direct laser triangulation level measurement verification system has been amended. By the results of the experimental data show that:after RBF neural network calibration good approximation to the true value of liquid level height.Put forward and set up to five degrees of freedom dynamic model of liquid level measurement system, deduced mathematical model of dynamic response, on this basis, the finite element analysis software ANSYS modal analysis is carried out on the system, and calculate the system5order natural frequency and vibration patterns, the key components of the detection system also has carried on the analysis and verification of the stress and strain. For vibration interference problems of the detection device by external systemic, analyze the vibration and vibration reduction processing, and computer simulation analysis are carried out using MatLAB software.The main components of the liquid level measurement system have been built and analysis. Systemic vibration has been analysis and damping.The simulation analysis for vibration by using Matlab.Level measurement system needs to be fast, accurate positioning and presence of vibration and other interference factors specific circumstances, the use of zero-zero phase difference tracking control (ZPETC) and the disturbance observer (DOB) combined tracking robust control as the inspection system of linear motor control strategy. Can effectively reduce the tracking error, and to improve the accuracy of the movement. The disturbance observer allows the system has a strong interference suppression capability and meets the robustness requirements, so that the level detection process can be more stable and effective working time.LabVIEW virtual instrument technology, the development of the system’s control software, system software acquisition and exercise joint control, to ensure the accuracy of the signal acquisition and analysis software, real-time computing, graphics and digital two forms display level and sedimentation rate situation. The software system also can complete alarm information storage, printing and other functions.The accuracy of the system has been experimental. The main factor of system errors has been analysis. The precision experiments show:absolute measurement accuracy and repeatability of measurement accuracy of the system in less than10μm, the relative error does not exceed0.3%, to meet the requirements of the the salt spray sedimentation rate level measurement accuracy. Experimental studies to prove the feasibility of fog deposition rates level measurement system, advanced reliability and practicality.