Study Of Underground Mine Locomotive Precise Positioning Technology

Mine transportation is an important part of the safety in production of coal mine, and the locomotive is an important tool for transport of coal mine. It can schedule the locomotive effective and reasonable, reduce accidents in mine transportation, improve transport efficiency of mine to achieve precise positioning of underground mine locomotive. So precise position technology of underground mine locomotive was researched.Firstly, the existing mine positioning technology at home and abroad was introduced. Secondly, the shortcomings aspects and improving of these technologies was researched and analyzed. Lastly the locomotive positioning technology based on TDOA and RSSI was proposed. The main contents are as follows:1) The time difference of ultrasonic and radio wave’s propagation time was used to measure the distance. Because the locomotive was a movement in the process of locating, and the ultrasonic propagation speed was slow, it would produce the locomotive movement error. So the movement error was replaced by distance error between the locomotive and beacon nodes. The corrected distance was analyzed and calculated. The initial position of locomotive was estimated by weighted least square method and it was corrected by Taylor series of least square method.2) The received signal strength of wireless was used to measure the distance. Because the mine environment was bad and the wireless signal was not stable when it was communicating. It would get larger error of the distance. The Gauss model and the weighted model are combined to get the stable RSSI values then the RSSI values were converted into the distance. The weighted least squares estimate was used to estimate the initial position of locomotive. Just use the weighted least squares method cannot reduce the number of uncertain factors effectively. The beacon nodes take as unknown node. The above method was used to calculate the errors between the estimated position and actual position of the beacon nodes. Each error was given a weight value. The larger of the distance between beacon nodes and locomotive the smaller of weight value. The final position was the plus of initial position and corrected error.3) MATLA simulation experiment was used to test the improved mine locomotive location technology. The results showed it has higher positioning accuracy than the traditional positioning technique and it meet the need of the transport in underground mine. In the experimental test platform, the positioning technology was tested and the test results showed that it can meet the need of underground production.