WO2015161391A1 - System for locating mobile objects inside tunnels in real time - Google Patents

Abstract

The invention relates to a system for locating or monitoring, in real time, persons and objects which are mobile inside tunnels, with high infrastructure density, by means of estimating lengths, angles or patterns obtained via electromagnetic signals, characterised in that the real-time location system (WILOS-RTLS) consists of four essential means for performing the locating: an optical fibre/UP Ethernet switch (1), stationary RTLS devices (2), a mobile TAG device arranged on machinery and personnel (5) and location calculation software (6); the RTLS devices (2) receive a corresponding RF interface wireless signal (4) from the mobile tag device (5) having an unknown position, which emits the RF signal thereof using microsecond periodicity; when at least two stationary RTLS devices (2) receive the RF interface wireless signal (4) from the mobile device (mobile tag on machinery or personnel) (5), said devices estimate the time differential of arrival of the RF interface transmission (4) (TDoA), and then send the estimated information, over the wired network infrastructure via an optical fibre/UP or wireless Ethernet switch (1) by means of an RF interface between stationary devices (3), to location calculation software (6); thus, the information received from at least two (one dimension), three (two dimensions) or four (three dimensions) RTLS devices (2) is processed in the software (6) in order to apply mathematical lateration techniques that is based on the TDoA information; finally, once the position has been estimated in said software (6), said information is held in order to be used in any application that can create graphs and adapt to an interface that is suitable for the location scenario.

Description

 TITLE: "REAL-TIME LOCALIZATION SYSTEM OF MOBILE OBJECTS INSIDE TUNNELS"

Background of the Invention

 The invention relates to a real-time location or tracking system for mobile objects and people inside tunnels, such as mining, which integrates one of the many radiofrequency technologies to estimate distance, technology that has been developed To be part of the RTLS (Real Time Location System) genre, although there are multiple real-time location estimation techniques using electromagnetic signals, the relevance of this invention is that, regardless of the type of technology used, an adaptation, design and development of electronic media and software to be able to use them in the geography and environment of tunnels, whether they are mining, transportation or whatever the interior scenario of the excavation type inside some soil. It should be clarified that a "Positioning" system is based on standardized spatial references to global scenarios, for example absolute coordinates in latitude and longitude, instead a "Location" system is oriented to use relative references according to the scenario in which it is used , can be metric distances, counting points, movement times, etc.

Historically, different navigation or positioning technologies have been used, due to military necessity in their principles and subsequently adapted to civilian needs, to name the best known are radar and GPS systems, which have relied on the advancement in the technologies of the communications by electromagnetic signals. Although the systems mentioned above have been successfully functional in outdoor environments, they have not been so in highly populated areas where their signals are interfered by the high density of buildings as well as in underground environments. This coverage gap, for example, of GPS systems, has challenged research in the use of wireless communications technologies, which have been increasingly widespread in our daily lives, an example of this has been the improvement of accuracy through combination of GPS and cellular telephony (A-GPS), which however, even in buildings with dense structure, does not reach precision less than tenths of meters.

 Currently there are different commercial systems of the RTLS type, which use RFID, Wi-F¡ or UWB (Ultra Wide Band 5GHz>) technologies. Each of them offering different levels of adaptation according to the installation scenario. For the specific case of this document, the design of the final system deals with the use of the RTLS system information modified to the geometry of tunnels and their circuits in their different combinations by electronic and software means.

A location or positioning system aims to obtain a spatial position result in one, two, or three dimensions using different geometric techniques based on estimation of length or angles with respect to known references (latency, angulation or stage mapping), these Geometric techniques are based on the estimation of times and / or angles; of arrival or emission of a signal, in our case of an electromagnetic signal. The base architecture to perform location, is based on fixed devices (installed in a known position) and a mobile device (unknown location), from which the latter emits or responds to a signal which allows estimating arrival or time positions for one or several reference devices, finally, knowing the speed of the signal in the traveling medium or arrival lags, lengths and / or angles are estimated to subsequently estimate spatial position.

 Already described the general architecture of a location system and the use of any of them that generally focus on spaces with obstacles, multiple rooms, etc. However, there is a particular scenario where, due to the physical nature of an electromagnetic signal, there is no free transmission in the entire workspace, since high mineral density barriers completely block the transmission itself, this is the case of tunnels of the type excavated or artificially constructed. Here is where a new strategy should be proposed to consistently estimate the location of a mobile within the tunnel (s) through which it travels, with the possibility of switching between them without losing its tracking.

The invention solves this problem of the technique by means of a "Location System with geometric estimation by time parameters and / or angles of electromagnetic signal, transmitted between fixed and mobile devices, with location x, y, z of the last along one or several interconnected tunnels, differentiating 0n which of them is found and delivering relative position information according to the infrastructure of the circuit of the same to later be integrated into some visual monitoring interface ". Regarding the state of the art, for location and monitoring in general, we can cite the patent of invention EP2003028, which refers to a redundant device for location, tracking and recovery of vehicles, based on the VLU5 technology known for the recovery of stolen, missing, crashed or similar vehicles constituted by a device called DLU that is the result of joining GSM technology to Radio in a single set of hardware by integrating the two technologies as redundant systems, providing new functionalities through the use of the network tools available in mobile phone technology.

 Another patent for localization is the invention patent ES 2418030, which refers to a method and system for locating and tracking a mobile device in a wireless node network.

The method comprises:

 - receive, the mobile device (D), a series of wireless signals from stationary nodes (n1 -n8);

 - extract and analyze power information from wireless signals;

 - generate estimated power information associated with a node from which the mobile device (D) has not received a wireless signal, in a given period, or has received it but its power is very weak, applying a correction factor to power information prior obtained for said node in a period prior to said determined period; Y

- determine the position of the mobile device (D) using the extracted power information, also using said estimated power information. The system is adapted to implement the method of the invention.

 Another invention patent is ES 2387815, which refers to a system for locating a user of a mobile device within a predetermined area, when said user makes a telephone call within a zone

default (100), characterized in that it comprises:

 - a beacon equipment (10) for defining said area

default, which includes:

 - a device with local area access technology

(1 1) configured to define said predetermined zone (100),

 - a device (12) with wireless access to a mobile telephone network (30),

 - a smart card with a user identification module (13),

 - storage means of at least one first access key to said predetermined zone (100) associated with said user, and by which said mobile equipment (20) includes:

 - said local area access technology, and - storage means of at least a second access key to said predetermined zone (100), - means for notifying the mobile telephone network (30) that the telephone call is a call made within the predetermined area (100); further characterized in that the system comprises:

 - means ρβψ detect the entry of said mobile equipment in the predetermined area,

- means to establish, in response to such detection, secure communication between mobile equipment and beacon equipment, - means for authentication and registration of said mobile terminal in the predetermined zone by checking for equality between said first and second access keys of beacon equipment and ηηόνϋ equipment, respectively.

Brief description of the figures

 To better understand the essential characteristics of the invention, for real-time location or tracking of mobile objects and people inside tunnels, it will be described according to the figures that are an integral part of the invention, without meaning restrict it to obvious modifications that may arise, where:

 Figure 1 shows a view of a pipeline diagram, location distribution of RTLS boards, in a tunnel circuit.

 Figure 2 shows a view of a diagram or functional architecture of the WILOS-RTLS location system.

 Figure 3 shows a view of the general implementation of the WILOS-RTLS communication system, for the monitoring, location and visualization of mobile media.

 Figure 4 shows a view of a tunnel circuit with the installation and distribution of the system, for real-time monitoring, location or tracking of mobile objects. Description of the Invention

According to figures 1 to 4, the real-time location or tracking system of people and moving objects inside tunnels, the application focuses on the use inside a tunnel within a Loop carrying mineral, as shown in figure 1, where there are routes shares that must be monitored by the operator, who supervises the road signs in the circuit, assisted by an automatic traffic light system. In this Loop, the trucks take the different routes and directions, and must be coordinated through a traffic light control (manual or automatic), and through communication with a dispatcher, who visualizes the continuous location of the vehicle tracking.

 Regardless of a particular application, the system supports location from open scenarios to complex tunnel circuits with bifurcations and different levels, being able to locate in three spatial dimensions (X, XY, XYZ).

 The real-time location system (WILOS-RTLS) is made up of four essential means for localization, a fiber optic ethernet switch / UP (1), WILOS-RTLS fixed devices (2), a mobile TAG device arranged in machinery and personnel (5) and a Location Calculation Software (6).

WI LOS-RTLS devices (2) receive a corresponding RF interface wireless signal (4) from the TAG mobile device (5) of unknown position, which emits its RF signal intermittently in the order of the msec. When at least two WILOS-RTLS fixed devices (2) receive from the wireless RF interface signal (4) from the mobile device (mobile tag in machinery or person) (5), they estimate the differential arrival time of the transmission of RF interface (4) (TDoA), to then send the estimated information, through the wired network infrastructure via an Ethernet fiber optic / UP switch (1) or wireless via (RF interface between fixed devices) (3), to a location calculation software (6). In this way, the information received from at least two WILOS-RTLS devices (2) (one dimension), or three (two dimensions) or four (three dimensions), is processed in the software (6), to apply mathematical latency techniques supported by the TDoA information. Finally, once the position in said software (6) is estimated, this information is available to be used in any application that graphs and adapts to an interface according to the location scenario.

 Since, the location infrastructure is based on TCP / IP (UTP, F.O, or Wireless), the WILOS system can be combined, through sub networks, for different forms that take whatever the geometry of the workspace.

 The complete implementation of the WILOS system for location and position visualization (Figure N ° 3), is constituted from a visualization computer (9), HMI industrial interface server, OPC, SC5ADA (8), server with WILOS RTLS calculation software (8), connected in TCP / IP Ethernet or Fiber Optic network through (1), or Wireless extended through (10), to finally reach the fixed location devices (2) who receive an RF signal from TAGs for people (4) or mobile (6a) being the mobile objectives (6a) of unknown position to be located. In this way, any variant of distribution of the RTLS fixed devices (2) is supported to adapt to any location geometry.

 The necessary means for the composition of the complete system are:

 1) Fiber optic Ethernet switches or UTP cabling.

 2) RTLS Fixed Devices for receiving RF location signal, and retransmission of information via Ethernet TCP / I P.

3) RF air interface for communication between devices (2). 4) RF air interface for locating mobile TAG (5) or (6) from RTLS fixed devices (2).

 5) RF emitting TAG devices (4) transportable by people.

 6) RF emitting TAG devices (4) transportable by vehicles or any mobile machine.

 7) Server with software for location calculations for information received from (2) and geometric adaptation to the stage.

 8) Server with OPC Industrial Software (OLE for Process

 Control), HMI (Human Machine Interface) or SCADA

 (Supervisory Control And Data Acquisition).

 9) Computer Display console for industrial graphic location interface.

 10) Wireless Router ton WDS capability (Wireless Distribution System) for wireless network expansion to hard-to-reach areas or for system portability requirements.

Tunnel Circuit Adaptation through WILOS.

The complex geometry of space, in a circuit of underground tunnels, makes it necessary to propose a strategy that covers the largest volume of work, given this, and using the network qualities of the WILOS system, the application is made to tunnels through the use of distinct networks of devices, and approximation of curvatures by means of linear sections between at least two fixed devices. Figure N ° 4 shows the strategy used by assigning devices to two different networks, where, (1) corresponds to the devices of network N ° 1, and (2) to those belonging to network N ° 2, the lines that bind each other to devices, shows the coverage that they cover and approximate in the different zones and forms of the circuit.

 A complete functional system of location in tunnels is made up of different parts from the hardware and communications to the processing software and visual interface. The following scheme shows the different levels that combined result in a location system adapted to tunnels and integrated into an industrial communications platform and visual interface.

 The architecture shown shows the stages that involve an RTLS system that, combined with engineering and software, is able to adapt the location platform to a tunnel infrastructure and OPC communications platform (OLE for Process Control) and industrial-type visual interface HMI (Human Machine Interface). In this level diagram, if the software did not exist, an engineering design in the distribution of the hardware, it would not be possible to operate an RTLS system in a tunnel circuit, nor unless this was compatible with industrial OPC and HMI platforms, It is at these stages where, using media, assembly design and software, a functional and fully functional system is achieved to this new tunnel scenario in any of its variations in the number of connections and circuits.

The final functionality of the system aims to obtain the position of a mobile object at least through the extension (one dimension) of a tunnel and these can be found and move between any of them, in turn must support multiple mobiles at once in any of the detection zones having a resolution in meters defined by the application requirement, starting from one meter as the minimum location accuracy.

 Regardless of the RTLS location platform used, the post system will process the information and restructure it by converting location x, y, z from RTLS to an x position, and, relative z, which is adapted by using extra parameters to the position coordinate information depending on the tunnel where the mobile is located, this by means of software algorithms that transform the generic position information into relative information and adapted to the tunnel circuit. After the relative position adaptation, this information is packaged in a protocol for its retransmission, to finally integrate it into OPC communications by creating an algorithm comprising the data packet from the OPC software, transforming it into this platform in which through any compatible HMI software will create a visual location monitoring interface.

In a network of tunnels with different levels and bifurcations, a total coordinated work space cannot be considered since the dimensions of the terrain and non-precise forms of the excavations do not allow to accurately model a well defined space, therefore, the best resource is to treat the tunnels as independent but combinable workspaces since they have different connections and accesses between them. Since an RTLS system aims to be used in spatially defined work spaces, with identifiable obstacles, it is necessary to adapt them to a tunnel space where the greatest relevance in them is to locate their extension, in the specific case, in dimension of the its trajectory, which is generally not linear, here is to locate on an "X""Y" axis or "Z is not trivial, but it is feasible by" Approximation by linear sections "(a curve can be approximated by the union of multiple straight lines between different points of the same), as well as the interconnection between several of them by combining" Multiple networks of devices ", all this finally integrated by a software with the appropriate algorithms to process this space model.

 Taking as a general scheme for a tunnel circuit, Figure N ° 1, three different continuous tunnel paths are plotted, which are connected and combined with another in one or several intersections, for this reason and due to the original design of a RTLS system to work in a space with rectilinear characteristics and precisely measurable and known dimensions of space, the simplest alternative of using a location system in this scenario is to treat each tunnel as a different workspace, so that later the information obtained from each one, it is combined and post-processed automatically and with an easily workable format for the subsequent construction of a visual interface for monitoring the location of the tunnel network. In this way, an RTLS hardware distribution strategy is designed in a distributed way as "multiple networks" of devices where each network is installed in a tunnel with continuous trajectory, differentiating each continuous tunnel and the network of devices associated with it .

Claims

RE IV INDIC AC IONES 1 .- Real-time tracking or tracking system of people and mobile objects inside tunnels, with high infrastructure density !, by estimating lengths, angles or patterns, obtained through electromagnetic signals, CHARACTERIZED because the system Real-time location (WILOS-RTLS), is made up of four essential means for localization, a fiber optic Ethernet switch / UP (1), fixed RTLS devices (2), a mobile TAG device arranged in machinery and personnel ( 5) and a Location Calculation Software (6); RTLS devices (2) receive a corresponding RF interface wireless signal (4) from the TAG mobile device (5) of unknown position, which emits its RF signal intermittently in the order of the msec; when at least two RTLS fixed devices (2) receive an RF interface wireless signal (4) from the mobile device (mobile TAG in machinery or person) (5), they estimate the differential arrival time of the RF Interface emission (4) (TDoA), to then send the estimated information, through the wired network infrastructure through an Ethernet fiber optic / UP switch (1) or wireless via (RF interface between fixed devices) (3), to a software of location calculations (6); in this way, the information received from at least two RTLS devices (2) (one dimension), or three (two dimensions) or four (three dimensions), is processed in the software (6), to apply mathematical techniques of latency supported by TDoA information; finally, once the position in said software (6) is estimated, this information is available to be used in any application that graphs and adapts to an interface according to the location scenario.  2. Real-time tracking or tracking system of people and mobile objects inside tunnels, according to claim 1, CHARACTERIZED because, given that, the location infrastructure is based on TCP / IP (UTP, FO, or Wireless) ), the WILOS system can be combined, through sub networks, for different forms that take whatever the geometry of the workspace.  3. Real-time location or tracking system of people and mobile objects inside tunnels, according to claim 1, CHARACTERIZED because the complete implementation of the WILOS system for location and position visualization, is constituted from a visualization computer (9), HMI industrial interface server, OPC, SCADA (8), server with WILOS-RTLS calculation software (8), connected in TCP / IP Ethernet or fiber optic network via (1), or extended wireless through (10), to finally reach the fixed location devices (2) who receive an RF signal from TAG for people (4) and mobile (6a) being the mobile targets (6a) of unknown position to be located; In this way, any variant of distribution of the fixed RTLS devices (2) is supported to adapt to any location geometry.