Aiming at the requirements of fire indoor positioning technology

an indoor three-dimensional positioning system based on inertial measurement components is built. Firstly

micro-electro-mechanical system（ MEMS） inertial sensors is used to obtain necessary parameters during pedestrian motion. Then

based on algorithm of pedestrian dead reckoning（ PDR）

the number of steps and steps of the pedestrian walking are calculated in real time; the height of the position where the pedestrian is located is collected in real time by the air pressure sensor. Finally

by combination of wireless data transmission module and server processing

realize indoor three-dimensional positioning of pedestrians. Tests show that the system can meet the indoor three-dimensional positioning requirements of pedestrians under normal walking conditions.