Elastic correction of altitude errors in indoor location system

Firefigher indoor location system is crucial for determining firefighter´s precise position in a burning building. When a firefighter encounters dangerous, the commander could immediately obtain his position information by the system. A major problem with the personal navigation system is due to the imprecision of sensor measurement. Altitude information is important for the rapid rescue operation and an error in the altitude measure will greatly prolong the golden rescue time. In this paper, we propose a methodology, called elastic correction of altitude error, for reducing the navigation altitude errors made by the change of temperature and atmosphere pressure. Elastic altitude correction is based on a synthesize of heading, pitch information of firefighter detected by inertial measurement unit (IMU) sensor. The proposed method could not only fulfill the requirement of firefighter positioning system, but also useful in other navigation systems.