Development Of Airbone Methane-monitor Based On Wireless Communication

With the development of coal economy,more and more attention has been paid to the safety of mine production.Gas accidents are responsed for very large proportion of mine accidents,which seriously lead to the loss of mine production.Measurement and detection for methane in real time are of great significance to the safety of mine production.Airbone methane-monitor is taked granted of the most important auxiliary equipment in the safety of mine production,by pre-designed alarm and lock control to make sure the safety of mine.At present,black-and-white elements,as the key components to detect methane concentration and be used in airbone methane-monitor equiped on the Monorail crane,are not so reliable and conviced in the accuracy and reliability,and needed to be adjusted frequently.So it is limited.Not only that,but also the single-machine mode of device,just to detect the concentration near the device and can not work with other devices to achieve other safety management functions.Finally,the traditional relay,as the key part of output,is out of dated because of long time delay and bad characteristics of mechanical contactors in the mine environment.Aiming at the problems of device in market,such as large measurement error,low reliability of block output and imperfect communication function,a new kind of airbone methane-monitor is designed and developed to reslove these.The main works and achievements of this paper are as follows:Related information at home and abroad is collected to show current research and the status of product.At the same time,the experience of Taiyuan Mine Machinery Electrical Incorporated Company,coming from the feel of using this kind of products for many years and the new demand for products,is considered.On the basis of above two aspects,a overall framework design of the device,which includes the function of the device and object-oriented and systematic method to develop the device,is structured and comes into world.According to the overall scheme,Specific details in blueprint,for examples,the technology of concentration detection based on the spectrum absorption principle semiconductor laser,a new type of solid state relay,the communication technology of RS-485,CAN and wireless,and function of the device,are formed into specified shape and finally taked into practice on the condiction of the characteristics of underground.Then the hardware circuits,like STM32 microcontroller minimum system circuit,methane detection circuit,soft-start circuit,switching circuit for dual power supply,charge management circuit for battery,blocking output circuit,acoustooptic alarm circuit,frequency output circuit,human-computer interaction unit including key and display parts,RS-485 and CAN and wireless communication interface circuit,are designed and produced in PCB.The designing method of software combining top-down and bottom-up is adopted and carried out,which divides multi-tasks into fault handling and key scanning tasks and so on according to hardware circuits and function requirement.In order to make it run,subprograms used to do things in fixed steps for appliction,such as display,storage and communication,are programmed and compiled.The tasks and subprograms are managed by ?C/OS-? to realize the functions of the device including CAN bus and RS-485 bus and wireless communication,key setting,concentration detection,display in tube,frequency output,etc.The function of the device is debugged and tested in the laboratory with KA83 J sensor intelligent verification device and communication assistant.The experimental results show that the device achieves perfect function and has reliable and stable operation,which can be confirmed in swiching power supply between external power supply and battery,in charging management through battery charging circuit,in detection of concentration,in parameters storage and initialization settings,in the functions of sound and light alarm,in reliable lock control output,in the aspects of concentration upload and parameters setting by wire and wireless communication.