Study On Portable Emergency Rescue Location Technology Based On Inertial Measurement Unit In Enclosed Space

In the underground enclosed working spaces such as coal mines where underground water seepage,gas explosions and other accidents occur,or in large indoor or underground places where fire accidents or other accidents occur,due to the destruction of catastrophic accidents,the power system and various wireless or wired devices are usually immediately paralyzed.Under this circumstance,how to implement the emergency rescue quickly and efficiently,and how the trapped people carry out self-rescue work,are urgent problems to be solved.Taking this as the application background,this paper studies portable devices and positioning technologies based on inertial measurement units.The specific research content of this article includes:Firstly,the researches of indoor positioning and navigation are summarized,and the advantages of inertial positioning and navigation based on inertial measurement unit in the emergency rescue environment are discussed.The key technologies of indoor inertial positioning and navigation are elaborated in detail.Then,the existing step detection and step size estimation algorithms are simulated,and the error characteristics of the step size estimation algorithm are analyzed.According to the error characteristics,an improved algorithm is proposed.The algorithm can obtain higher step-rate estimation accuracy,reduce inertial measurement error,and improve positioning accuracy.Then,based on the roadway/corridor geometric constraints in the enclosed space,a roadway/corridor clustering algorithm based on subtractive clustering is proposed.The algorithm can accurately structure the inertial navigation data into a laneway/corridor structure.At the same time,according to the constraints of floor height,a floor clustering algorithm based on subtraction clustering is proposed.The algorithm can accurately separate the inertial navigation data of different floors so as to realize three-dimensional structural modeling of inertial navigation data.Afterwards,the paper analyzes the three-dimensional structural model calibration and matching algorithm based on directional features.Combined with the Dijkstra path fast search algorithm,indoor positioning and navigation based on inertial measurement data are basically realized.Finally,according to the requirements of the portable equipment in the research task proposed in the application background,this paper designs a set of dataacquisition,processing and output system based on STM32 single-chip microcomputer,and discusses and describes the detailed designing principle of the system and the hardware and software debugging process.In this paper,the previously proposed algorithms are implemented on the system in real time,and the processing results are transmitted to the computer for displaying.Simulations and experiments prove that the algorithms and hardware system designed in this paper are feasible.