CN105445776A - Indoor and outdoor seamless positioning system - Google Patents

Abstract

The invention discloses an indoor and outdoor seamless positioning system. The system employs the switching of two positioning schemes based on GPS positioning and MEMS positioning, and the flow specifically comprises the steps: (1), refreshing an intelligent terminal in a timing manner, detecting the intensity of a GPS signal, and judging the intensity of the GPS signal: starting a positioning scheme based on the GPS when the intensity of the GPS signal is greater than or equal to a threshold value, or else, starting the positioning scheme based on MEMS; (2), correcting the position of an initial point through a cellular network of the intelligent terminal during the switching of the two positioning schemes, receiving an existing WI-FI signal based on the MEMS positioning scheme through employing an intelligent cellphone positioning terminal, and correcting the moving position of a person; (3), uploading geomagnetic data and WI-FI data to a server when the intelligent terminal is connected with a WI-FI, and updating a geomagnetic fingerprint library and a WI-FI fingerprint library. The system can be used indoors and outdoors, effectively prevents other conditions from limiting the positioning, and is low in complexity. Moreover, the positioning precision can meet the actual demands.

Description

The seamless positioning system of a kind of indoor and outdoor

Technical field

Indoor positioning technologies field of the present invention, particularly relates to the seamless positioning system of a kind of indoor and outdoor.

Background technology

Along with the development of society and the progress of science and technology, the live and work of positional information to people becomes more and more important.

For outdoor spacious region, GPS (GlobalPositioningSystem, GPS) is widely used, and can meet the demand of people for positional information well.And for the interior of building such as buildings, tunnel, satellite-signal is by deep fades, the targeting scheme based on GPS cannot meet the demand of location.

For the orientation problem of indoor environment, researchers propose based on multiple indoor location technologies such as infrared ray, ultrasound wave, Bluetooth signal, Wi-Fi signals, and propose some targeting schemes.But still have a lot of problem need solve, such as: system complexity is high, low precision, be not easy to realize etc.In recent years, along with the development of inertial technology and electronics process technology, the cost performance of Inertial Measurement Unit (InertialMeasurementUnit, IMU) improves constantly, based on the targeting scheme of MEMS sensor by extensive concern, and think very promising solution.Domestic and international experts and scholars have done a large amount of research work to this.The MEMS positioning system of u.s.a. military affairs is in normal gait after 2 hours (about 8 kilometers), and error drift is only about 10 meters; The robot engineering center of Carnegie Mellon University of the U.S. have studied a set of shoe indoor locating system based on IMU, this system walking after one hour positioning error can control within one meter; Domestic Chinese University of Science and Technology proposes the targeting scheme merging GPS and IMU; Beijing University of Post & Telecommunication proposes the targeting scheme etc. based on IMU and Wi-Fi.

Summary of the invention

For above-mentioned prior art and Problems existing, the present invention proposes a kind of indoor and outdoor seamless positioning method, the present invention is merged based on GPS location and is located this two kinds of targeting schemes based on MEMS, realizes the seamless switching of indoor and outdoor surroundings location.

The present invention proposes a kind of indoor and outdoor seamless positioning method, utilize based on GPS location and the switching of locating these two kinds of targeting schemes based on MEMS, the flow process of the method specifically comprises the following steps:

The intensity of step 1, intelligent terminal periodic refreshing, detection gps signal, judges gps signal intensity:

When gps signal intensity is more than or equal to threshold value, start the targeting scheme based on GPS; When gps signal intensity is less than threshold value, start the targeting scheme based on MEMS;

Step 2, when two kinds of targeting schemes switch, utilize the position of the cellular network calibration initial point of intelligent terminal; Existing WI-FI signal is received, the position that calibration personnel is advanced based on smart mobile phone locating terminal can be utilized in MEMS targeting scheme;

Step 3, when intelligent terminal connects Wi-Fi, upload geomagnetic data and WI-FI data to server, renewal earth magnetism fingerprint base and Wi-fi fingerprint base.

Detect the intensity of gps signal in described step 1, specifically comprise the following steps:

The GPS module of intelligent terminal receives gps signal, obtains gps signal strength S _gPS, Rule of judgment is expressed as follows:

S _gPS>=S _{gPS_TH}or S _gPS<S _{gPS_TH}

Wherein: S _{gPS_TH}it is gps signal intensity threshold.

Described startup also specifically comprises following process based on the targeting scheme of GPS:

Intelligent terminal calls Google Maps API, loads Google Maps, starts the targeting scheme based on GPS; When adopting based on GPS targeting scheme, be placed in exercise data and the geomagnetic data of the MEMS sensor collector walking of pedestrian's tiptoe, accelerometer and gyroscope are calibrated for error, carries out gait detection, step size computation and direction estimation, extrapolate the position of personnel.

The described targeting scheme enabled based on MEMS, utilizes smart mobile phone locating terminal to receive WI-FI signal, carries out map match, improve positioning precision.

Compared with prior art, the present invention can use smart mobile phone, Bluetooth data transfer technology, sensor technology, Digital Signal Processing etc. to build the system of the seamless location of indoor and outdoor; Can use under indoor and outdoor, various scene, efficiently avoid the restriction of other conditions to location, and system complexity is low, positioning precision can practical requirement.

Accompanying drawing explanation

Fig. 1 is the entire block diagram of the seamless positioning system of indoor and outdoor of the present invention;

Fig. 2 is the process flow diagram based on MEMS targeting scheme.

Embodiment

Below in conjunction with accompanying drawing, technical scheme of the present invention is described in detail.

Integral Thought of the present invention adopts based on GPS targeting scheme with based on MEMS targeting scheme, realizes the seamless location of indoor and outdoor, meet the location requirement in various situation.The present invention includes two kinds of localization methods, that is: based on GPS localization method with based on MEMS localization method; And by the selection of these two kinds of localization methods, call and merge in the APP of smart mobile phone locating terminal.

The intensity of step 1, smart mobile phone locating terminal periodic refreshing, detection gps signal, according to gps signal intensity, system starts different localization methods (based on GPS localization method with based on MEMS localization method), and smart mobile phone locating terminal APP shows different interactive interfaces;

Step 2, when gps signal strength S _gPSwhen being more than or equal to threshold value, can think that gps signal is strong, meet positioning requirements, system adopts based on GPS targeting scheme, and determination methods is as follows:

S _GPS≥S _{GPS_TH}

Wherein S _{gPS_TH}be gps signal intensity threshold, rule of thumb set.

The data of advancing based on the targeting scheme collector of MEMS and magnetic data, calibrating sensors error;

The intensity of step 1, intelligent terminal periodic refreshing, detection gps signal, when gps signal intensity is more than or equal to threshold value, can think that gps signal is strong, meet positioning requirements, system just starts the targeting scheme based on GPS, the data of advancing based on the targeting scheme collector of MEMS and magnetic data, calibrating sensors error;

Now, smart mobile phone locating terminal calls Google Maps API, loads Google Maps, starts the targeting scheme based on GPS.And be placed in exercise data and the magnetic data of the MEMS sensor collector walking of pedestrian's tiptoe, calibrate for error to accelerometer and gyroscope, magnetic data is for building magnetic force fingerprint base.

Step 3, when gps signal intensity is less than threshold value, can think that gps signal is weak, the targeting scheme based on GPS cannot meet positioning requirements, and system just starts the targeting scheme based on MEMS, determination methods and step 2 similar.Now, utilize the exercise data and the geomagnetic data that are arranged on the MEMS sensor collector of personnel's tiptoe, carry out gait detection, step size computation and direction estimation, extrapolate the position of personnel.Targeting scheme based on MEMS is as follows:

Step 3.1, based on adopt in MEMS targeting scheme be PNI company produce SPACEPOINTSCOUT module, the sensor that this module comprises has accelerometer, gyroscope and magnetometer three kinds of sensors, and the data of output comprise 3-axis acceleration, hypercomplex number and magnetic data.

Step 3.2, the hypercomplex number utilizing MEMS to export generate coordinate conversion matrix, utilize transition matrix that the acceleration based on MEMS carrier coordinate system is transformed into geographic coordinate system, obtain the acceleration based on geographic coordinate system, and remove acceleration of gravity, transformational relation is as follows:

$\left[\begin{array}{c}{a}_N\\ a_E\\ a_D\end{array}\right]=\left[\begin{array}{ccc}{q}_0^2+q_1^2-q_2^2-q_3^2& 2(q_1{q}_2+q_0{q}_3)& 2(q_1{q}_3-q_0{q}_2)\\ 2(q_1{q}_2-q_0{q}_3)& q_0^2-q_1^2+q_2^2-q_3^2& 2(q_2{q}_3+q_0{q}_1)\\ 2(q_1{q}_3+q_0{q}_2)& 2(q_2{q}_3-q_0{q}_1)& q_0^2-q_1^2-q_2^2+q_3^2\end{array}\right]*\left[\begin{array}{c}{a}_x\\ a_y\\ a_z\end{array}\right]-\left[\begin{array}{c}0\\ 0\\ g\end{array}\right]$

Wherein: [a _xa _ya _z] represent 3-axis acceleration under carrier coordinate system, [a _na _ea _d] representing 3-axis acceleration under geographic coordinate system, g represents acceleration of gravity, generally gets 9.8m/s ², [q ₀q ₁q ₂q ₃] represent hypercomplex number, be specially:

q ₀＝cos(α/2)

q ₁＝sin(α/2)cos(β _x)

q ₂＝sin(α/2)cos(β _y)

q ₃＝sin(α/2)cos(β _z)

Wherein: α is the angle rotated around turning axle, cos (β _x), cos (β _y), cos (β _z) for turning axle is at the component in direction.

Step 3.3, obtain resultant acceleration according to the 3-axis acceleration under geographic coordinate system utilize threshold value to carry out gait detection, continuous print motion is divided into the set of each single step, obtains zero-speed rate adjusting point.Detection method is: choose the maximum point in resultant acceleration, and maximum point meets following relationship, that is: the threshold value being greater than setting interval greater than the threshold value set and maximum value of adjacent maximum point.Formula is as follows:

$\left\{\begin{array}{c}\mathrm{\&Delta;}T>T_{Th}\\ A>A_{Th}\end{array}\right.$

Wherein: Δ T represents the time interval of two zero-speed rate adjusting points, T _thand A _threpresent the critical value rule of thumb set.

Step 3.4 for each motion single step, to the 3-axis acceleration [a under geographic coordinate system _na _ea _d] carry out the single step step-length that quadratic integral obtains motion, integration method is as follows:

$\left[\begin{array}{c}{v}_{N\_i}\\ v_{E\_i}\\ v_{D\_i}\end{array}\right]=\left[\begin{array}{c}{v}_{N\_0}\\ v_{E\_0}\\ v_{D\_0}\end{array}\right]+\left[\begin{array}{c}\underset{j=1}{\overset{i}{\&Sigma;}}{a}_{N\_j}\mathrm{\&delta;}t\\ \underset{j=1}{\overset{i}{\&Sigma;}}{a}_{E\_j}\mathrm{\&delta;}t\\ \underset{j=1}{\overset{i}{\&Sigma;}}{a}_{D\_j}\mathrm{\&delta;}t\end{array}\right]$

Wherein: δ t represents the sampling interval of MEMS module, this module is 1/125s; [v _{n_0}v _{e_0}v _{d_0}] represent three axle speed under initial time geographic coordinate system; [v _{n_i}v _{e_i}v _{d_i}] represent three axle speed under the i-th moment geographic coordinate system;

$\left[\begin{array}{c}{S}_{N\_i}\\ S_{E\_i}\\ S_{D\_i}\end{array}\right]=\left[\begin{array}{c}{S}_{N\_0}\\ S_{E\_0}\\ S_{D\_0}\end{array}\right]+\left[\begin{array}{c}\underset{j=1}{\overset{i}{\&Sigma;}}{v}_{N\_j}\mathrm{\&delta;}t\\ \underset{j=1}{\overset{i}{\&Sigma;}}{v}_{E\_j}\mathrm{\&delta;}t\\ \underset{j=1}{\overset{i}{\&Sigma;}}{v}_{D\_j}\mathrm{\&delta;}t\end{array}\right]$

Wherein: δ t represents the sampling interval of MEMS module, this module is 1/125s; [S _{n_0}s _{e_0}s _{d_0}] represent three-shaft displacement under initial time geographic coordinate system; [S _{n_i}s _{e_i}s _{d_i}] represent three-shaft displacement under the i-th moment geographic coordinate system;

And then, the step-length of this single step can be calculated

Step 3.5, each single step to be added up, just can obtain the moving step sizes of any time;

Step 3.6, hypercomplex number and geomagnetic data is utilized to estimate direction of motion;

Step 4, when two kinds of targeting schemes switch, the position of the cellular network calibration initial point of smart mobile phone locating terminal can be utilized; Existing WI-FI signal is received, the position that calibration personnel is advanced based on smart mobile phone locating terminal can be utilized in MEMS targeting scheme.The cellular network of smart mobile phone locating terminal is utilized to improve the precision of initial position; When gps signal intensity is weak, enable the targeting scheme based on MEMS, utilize smart mobile phone locating terminal to receive Wi-Fi signal, carry out map match, improve positioning precision;

Step 5, in the process of whole location, utilize smart mobile phone Wi-Fi module and the existing Wi-Fi data of MEMS sensor module acquires and geomagnetic data, set up WI-FI fingerprint base and earth magnetism fingerprint base, and when smart mobile phone locating terminal connects Wi-Fi, upload the WI-FI data of collection and geomagnetic data to server, upgrade Wi-Fi fingerprint base and earth magnetism fingerprint base.

The invention provides the system of a kind of combination based on GPS targeting scheme and the seamless location of indoor and outdoor based on MEMS targeting scheme, the real-time of system and precision depend on smart mobile phone performance and the algorithm based on MEMS targeting scheme.The part that this programme does not describe in detail can be applied prior art and carry out realizing and optimizing.

Claims (4)

1. an indoor and outdoor seamless positioning method, is characterized in that, utilize based on GPS location and the switching of locating these two kinds of targeting schemes based on MEMS, the flow process of the method specifically comprises the following steps:

The intensity of step (1), intelligent terminal periodic refreshing, detection gps signal, judges gps signal intensity:

When gps signal intensity is more than or equal to threshold value, start the targeting scheme based on GPS; When gps signal intensity is less than threshold value, start the targeting scheme based on MEMS;

Step (2), when two kinds of targeting schemes switch, utilize the position of the cellular network calibration personnel initial point of intelligent terminal based on GPS targeting scheme; Smart mobile phone locating terminal is utilized to receive existing WI-FI signal, the position that calibration personnel is advanced based on MEMS targeting scheme;

Step (3), when intelligent terminal connects WI-FI, upload geomagnetic data and WI-FI data to server, renewal earth magnetism fingerprint base and Wi-fi fingerprint base.

2. the seamless positioning system of a kind of indoor and outdoor as claimed in claim 1, is characterized in that, detects the intensity of gps signal, specifically comprise the following steps in described step (1):

The GPS module of intelligent terminal receives gps signal, obtains gps signal strength S _gPS, Rule of judgment is expressed as follows:

S _gPS>=S _{gPS_TH}, or

S _GPS<S _{GPS_TH}

Wherein: S _{gPS_TH}it is gps signal intensity threshold.

3. the seamless positioning system of a kind of indoor and outdoor as claimed in claim 1, is characterized in that, described startup also specifically comprises following process based on the targeting scheme of GPS:

Intelligent terminal calls Google Maps API, loads Google Maps, starts the targeting scheme based on GPS; When adopting based on GPS targeting scheme, be placed in exercise data and the geomagnetic data of the MEMS sensor collector walking of pedestrian's tiptoe, accelerometer and gyroscope are calibrated for error, carries out gait detection, step size computation and direction estimation, extrapolate the position of personnel.

4. the seamless positioning system of a kind of indoor and outdoor as claimed in claim 1, is characterized in that, described in enable targeting scheme based on MEMS, utilize smart mobile phone locating terminal to receive WI-FI signal, carry out map match, improve positioning precision.