The Application Research Of CAN+Wireless Transmission In The System Of Mine Compositive Supervision

The traditional communication mode of the safety monitoring control system of coal mine is non-bus controller cable transmission. In recent years, the mine monitoring control equipment based on RS485 bus was used in coal mine, which has communication cable and optical fiber cable as its transmission media. In order to solve the disadvantages of wired system, the author put forward a coal mine monitoring signals transmission method based on CAN bus technology and wireless data transmission technology in this essay, after analyzing the technology of mine monitoring control system at home and abroad. For the sake of proving this theory , the author developed a set of system which collect the information of gas concentration and the work condition of machine underground mine , and transmit it to the receiving main station linked to the CAN intelligent node through the CAN bus network channel, afterward, the CAN intelligent node underground mine collect the information in the wireless receiving main station through RS232 serial port , and then send it to the ground mine CAN intelligent node through bus.In order to build a set of system of wireless transmission network, the communication between the control center and mine, the author used the wireless data transmission module MDS2710 which frequency is between 220MHz and 240MHz as signal transmission equipment to apply to the mine. The transmission rate of this system was set as 19.2Kbps, and using time division multiple access round robin scheduling algorithm to achieve the control and data transmission from one-point to multi-point. Use MDS 2710 wireless data transmission module to achieve the collection, monitoring as well as control of those distal end various data by control center. And also use the latest technology to improve the properties of narrowband date wireless telemetering equipment in multiple access systems. With utilization of digital signal processing (DSP) and explosion proof installation technology, the performance and reliability of radio become more excellent.In this paper, it designs CAN controller node with microcontroller 89C52, CAN controller with SJA1000, bus driver with 82C250. It designs and develops CAN intelligent node interface circuit, and also on the basis of wireless transmission, designs vibrating accelerometer sensor and methane sensor, conditioning circuit and A/D converter. This design mainly realize the function of collecting the data underground mine and using CAN bus transmission. Applying software written in VC++ language, the design realizes a simple and friendly management interface monitoring control system super-computer, and complies read-write program. Slave-computer, which is designed by single chip microprocessor is used chiefly to achieve the sending and receiving of CAN message.