Research On Indoor Positioning And Attitude Sensing Based On Inertial Navigation Principle

Our country’s economy is in rapid development period in recent years, and buildings are also correspondingly three-dimensional, complicated and diversified under the over-all environment of the rapid development of cities. However, with the urbanization process in our country, fire happens from time to time in buildings such as shopping malls, etc. The more complex and changeable indoor fire situation makes the casualty rate of firefighters in the front line of rescue increase year by year. This topic focuses on the personal life security issue and rescue quality of fire rescue workers in indoor fire environment, and puts forward a kind of indoor locating system design and the algorithm research of positioning accuracy based on inertial navigation principle.This article elaborates the designed hardware platform of the indoor positioning system systematically. The platform takes the hardware such as locator, chest data terminal and back data terminal, etc. as the foundation, adopts the STMicroelectronics STM32F405 chips as the main control chip, and carries sensors such as gyroscope, accelerometer and magnetometer, etc. to constitute the strap down inertial navigation system. The indoor positioning system takes Newton’s basic mechanics as the theoretical basis, using the gyroscope and accelerometer carried on the locator at the feet of fire rescue workers to measure the marching angular velocity and acceleration of the located people, calculate using the measured data, and get the speed and position as well as motion curve of scene rescue workers. In order to improve the positioning accuracy of the system, we study the gesture decoding algorithm, coordinate transformation algorithm, speed solution algorithm and location solution algorithm involved in the system, analyze the generating mechanism of the coning error, rowing error and scrolling error in the system, and deduce the compensation optimization algorithm for all kinds of errors.Through repeated experimental measurement and algorithm optimization, results show that the fire rescue workers indoor positioning system can effectively achieve the expected design goals, and has reached the positioning accuracy of level accuracy of 4% total run of rescue workers, vertical precision of +/- 0.5 m. The indoor positioning system does not rely on the external signals, nor radiates energy into the surrounding environment; it is undisturbed and able to work in a variety of hostile environment. The system can be widely used in all aspects of maintaining the social stability and life safety, such as fire disaster scene, anti-terrorism forces battle field as well as detection or rescue scene of danger zones of mines, etc.