The Research And Design Of A Laser Ranging System Of Freighter Oil Tank Based On Embedded System

In the measurement of the freighters tanks’ oil mass, the traditional way is using tape with lead weights. Through measure the distance of the oil on the tape to determine the depth of the oil, then the sailor has to look-up table to get the oil mass according to temperature and other factors. This kind of measuring method not only cumbersome, but will also bring oil to the deck that is a hazard to both security and health. Now the small laser range finder for sale ordinary can only provide the function of the measurement and display of fixed targets which cannot meet the need of the requirement of the oil tank.This article compared the advantages and disadvantages of the small laser range finders. To overcome the disadvantages of unable to accurately measure dynamic target, unable to storage and transport large amounts of data, and considering the actual demand of the measurement of the freighters tanks’ oil mass, this subject put forward a laser range system based on embedded system which can realize not only the range of distance, but also an efficient processing of the measurement data, and it can also provide encrypted storage, secure transmission. The system also has a support software client which can manage data and information of the system.Through the comparison of different laser ranging principles and measurement effects, in this article we choose phase laser range finding sensor to meet the requirement of the measuring distance and accuracy of the tanks. Meanwhile, we use Raspberry Pi as the master controller of the embedded system, combined with LCD touch screen, barcode scanning module and so on to accomplish the hardware design We also designed the GUI interface through Qt application development framework, cooperate with the LCD touch screen to meet the requirements of human-computer interaction. The realization of measurement data processing algorithms includes wavelet threshold de-noising and least square fitting. The security data transmission is realized by TCP protocol and MD5 algorithm. The mail transfer of the data is realized by using SMTP protocol and MIME protocol. The SQLite database is encrypted to make sure the safety of the databases.In the same time, the design of PC client is accomplished to view and manage the measurement data, employee information and tanks information convenient and intuitive. The management of measurement data of the PC client includes the update, query and Excel export of the data. And PC client also provide the query, insert and delete operation.After experimental verification, this system can achieve the desired requirements, various functions have been realized basically. The laser range finder can complete the function of data measurement, processing, storage, and upload. The PC client can realize the login security, measuring record query and export data, employee information management of the oil tank, etc. The interaction of the hardware and software is normal. This article has put forward a solution that is a laser ranging system based on embedded system, and also offers a reference to the measurement method of the oil tank in the future. The system has some practical significance.