In some areas of transport, because operators wrong control led to occur from time to time will mistakenly stopped, or keep accidents to the mines pose a serious safety hazard. The device is operated in the original train basis electrical vehicles automatically. Its operating speed electrical vehicle dynamics revealed that when a train go into planned regional and the location of the trigger electromagnetic sensors, location receivers will transmitted trigger signals to single-chip. Then single-chip issued warning, and in accordance with the received number of teeth frequency pulse signals to calculation. When travelling distance to meet design requirements, but the operator did not press the manual buttons, train will automatically way to the parking. Single-chip locks the speed on the first, then under lock pace to control parking style, thus achieving accurate parking. To meet the diverse transportation needs of the train, devices should be designed with a number of functions, and the primary function mainly to the completion of the parking around the exact security protection functions. Key words: location trigger;gear pulse; 555 timer; AT89C51 single-chip; I/O expansion 8155