Design Of Automatic Mahjong Machines Mahjong Tiles Surface Detection Device

Mahjong has been developing to be an international sports competition,accordingly mahjong machine market is developing toward internationalization. The existing mahjong machines are all made based on magnetic mechanism. The machines based on magnetic mechanism gives requirements and restrictions of the structure of mahjong machines and mahjong tiles, meanwhile, the machines based on magnetic mechanism have some shortcomings, including high cost, complex making technology, high future maintenance cost, convenient cheating, etc. The principle of demagnetization automatic mahjong machine proposed in this paper can help to solve the problem caused by magnetic material. Development status of domestic and foreign mahjong machines and mahjong tiles surface detection technology were summarized. To cope with the problems of the existing mahjong machines, a mahjong tiles surface detection device based on image processing and image recognition was designed in the paper. Two schemes for realizing the demagnetization mahjong tiles surface detection are proposed in this paper which were MC9S12XS128 MCU with OV7620 camera module and ARM STM32F103ZETT6 with OV7670 camera module.Firstly, the hardware design of the device were introduced in detail including core components selection and the design of peripheral circuits of each function module.The function module of hardware mainly includes main module 、 image acquisition、data cache、and real-time display. The system schematic diagram and PCB were also displayed at the end.Secondly, the software function of each module were described on the base of hardware platform introduction. The software function of camera initialization 、camera driver、image acquisition and image processing including gray conversion 、filtering and binarization were achieved, and then the final image of mahjong tiles surface was extracted.Moreover, after introducing the hardware design and software design of both two mahjong tiles surface detection devices in detail, both two mahjong tiles surfacedetection devices has also been experimentally investigated, the recognition accuracy was measured,which can be used for reliability evaluation.Finally, the results show that within a certain scope of velocity and light intensity, both two sets of mahjong tiles surface detection device have better accuracy and reliability. The device can realize the demagnetization of auto mahjong machines to some extent and provide a reference for pepole to study on it,the effect of this system also reached the design requirements basically.