Research On Automatic Selection Technology Of Mis-shelf Books In Library Based On RFID Location

The daily management of the library includes book arrangement,borrowing and returning,shelving and so on.Due to the increasing number of books in the library,the simple manual operation method has been unable to efficiently and accurately complete the book management work.The unmanned intelligent library management system based on RFID technology arises at the historic moment.However,it is an urgent problem for libraries to automatically screen misplaced books and accurately remove misplaced books from shelves.In view of the above problems,this paper studied an intelligent mis-shelf book selection system based on RFID positioning technology.The system located books through a single RFID reader.The system scanned books on the shelf in layers,identified and selected mis-shelf books to replaced the librarian’s error checking and sorting work.The system mainly realized two functions: orderly count the books on the shelf to find the books on the wrong shelf,and then record the information of the books;Accurate positioning of the wrong books is carried out to obtain the relative location information of the wrong books,so as to facilitate the removal of the wrong books.The main work of this paper is as follows:(1)Study the principle of RFID positioning based on signal strength.The composition of RFID positioning system was introduced.The working principle,characteristics and advantages of RFID were described in detail.The common RFID positioning algorithm based on signal strength was described.The advantages and disadvantages of the ranging model and the non-ranging algorithm based on fingerprint were analyzed.(2)Design the overall scheme of positioning and picking system for mis-shelf books based on RFID,and study the RFID localization algorithm for book sorting.The test platform and test environment were built.The hardware selection and software design were carried out.The bookshelf multi-layer synchronous scanning and single-layer sequential scanning were designed.According to the comparative test of the signal strength of the books labels received from different levels and different positions,the final scheme of single layer sequential scanning of bookshelves were determined.The electromagnetic simulation model of HFSS was constructed to obtain the electromagnetic radiation range and direction intensity data of the reader antenna.By combining the theoretical calculation of Friis transmission formula and the speed of the reader signal receiving,the guidance data such as the best scanning position and transmitting power of the RFID reader were obtained.(3)The RSS-based high-density book positioning model was constructed to realize book positioning.By setting multiple sets of key parameters of the picking system for multiple trials,the RSS sequences of all book tags in the reader scanning area and the number of scans were obtained.The filtering model was established by the filter function to extract the feature value m RSS of the RSS of each book tag.m RSS was used to construct a book positioning model based on LM-rational fitting method by using the feature value m RSS of the book tag and the actual coordinate position data of the book tag.Then,the books were sorted by combining the number of scans of the book tag to obtain the location information of the wrong shelf books.(4)Realize the development and experiment of automatic picking system for wrong shelf books.The experiment proved that the RFID positioning-based automatic library wrong-shelf book picking system could obtain the wrong-shelf book location information accurately and stably,the system had 100% probability of scanning the wrong book layer,and the average absolute error of wrong book positioning within the layer is 1.59 cm,which has high robustness.