WO2015086062A1 - Method for positioning humans and devices in underground environments - Google Patents
Method for positioning humans and devices in underground environments Download PDFInfo
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- WO2015086062A1 WO2015086062A1 PCT/EP2013/076217 EP2013076217W WO2015086062A1 WO 2015086062 A1 WO2015086062 A1 WO 2015086062A1 EP 2013076217 W EP2013076217 W EP 2013076217W WO 2015086062 A1 WO2015086062 A1 WO 2015086062A1
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
- G01S5/02—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
- G01S5/0273—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves using multipath or indirect path propagation signals in position determination
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
- G01S5/02—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
- G01S5/0257—Hybrid positioning
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
- G01S5/02—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
- G01S5/0252—Radio frequency fingerprinting
Definitions
- Figure 1 shows a schematic flowchart of estimation of a position in accordance with an exemplifying embodiment of the present invention.
- the estimated position is then presented on a display unit of for example a personal digital assistant (PDA) or a control system.
- PDA personal digital assistant
- Any existing wireless system infrastructure in the underground environment can be exploited by the positioning system by using it to transmit data from the RUs to the decision making system and from the decision making system to the display unit.
- Another advantage is that in order to rely only on WLAN and/or UWB, the transmitter density has to be high; hence extra sensors are required only for the positioning. Using the IMU (6) it is possible to dead reckon for some time which means that less radio sensors are needed.
Abstract
The present disclosure relates to a method for localisation and positioning of humans and devices in underground environments. Several different wireless technologies are used and different important variables are extracted. These variables are fed into a decision maker system to estimate the current position of a human or a device. The decision maker system also compensates for humans/devices in non-line-of-sight (NLOS) conditions to obtain a high accuracy of the true position.
Description
Method for positioning humans and devices in underground environments
TECHNICAL FIELD
The present invention relates to the technical field of indoor positioning. In particular, it concerns a method for positioning humans and devices in underground environments using wireless signals.
BACKGROUND
Two very important issues for mining companies today are to increase the productivity and improve the safety all over the plant for the workers. Enhancing the level of automation and improving the operational performance is a key to meet these challenges. One way to achieve this is by introducing a positioning system to track devices (vehicles, equipment, machinery, etc). The usage of position information outdoors has increased significantly during the last two decades and among the reasons are high availability and low cost of GPS systems. This has made GPS positioning systems ubiquitous. However, GPS positioning systems are inappropriate for indoor positioning since the radio signals will have difficulties to penetrate thick walls, roofs etc. Therefore, other solutions are necessary to this end.
There are numerous approaches on how a reliable position estimate can be achieved indoors and especially underground. One of the common approaches is to rely on radio networks. The basic idea is then to measure the distance to a number of wireless transmitters at known positions. A widely used method for deriving distance information to a wireless transmitter is to measure the received signal strength (RSS) of an incoming radio wave. Distances can also be determined by measuring time-of-arrival (TOA) and time-difference-of-arrival (TDOA) of the radio signal. There are a number of problems of only relying on radio data. Two of these are coverage and non-line-of-sight measurements.
Non-Line-of-Sight (NLOS) is a condition where the radio transmission of a signal from a transmitter to a receiver on a path is partially obstructed. The main problem with NLOS
measurements is that they will deceive the triangulation algorithm. Therefore, it is important to detect if a distance measurement is NLOS and take appropriate measures. Example of some known NLOS detection techniques are: Running variance, Confidence metric, Delay spread and Change of signal to noise ratio.
For explanations and a comparison of different NLOS detection techniques, see J. Schroeder, S. Galler, K. Kyamakya, and K. Jobmann, "NLOS detection algorithms for ultra-wideband localization," in Positioning, Navigation and Communication, 2007. WPNC '07. 4th Workshop on, March 2007, pp. 159 -166.
Whenever NLOS is detected the measurements can either be discarded or (instead) the NLOS error can be mitigated using a method like in: C.-D. Wann, Kalman Filtering for NLOS Mitigation and Target Tracking in Indoor Wireless Environments, V. Kordic, Ed. InTech, May 2010, downloaded: 15-04-2013. [Online]. Available: http://www.intechopen.com/books/kalman-filter/kalman-filtering-for-nlos-mitigation-and- target-tracking-in-indoor-wireless-environment and C.-D. Wann and C.-S. Hsueh, "NLOS mitigation with biased kalman filters for range estimation in uwb systems," in TENCON 2007 - IEEE Region 10 Conference, 2007, pp. 1-4. To improve positioning accuracy RSS and TOA/TDOA can be combined as shown in: Jie He, Yanwei Yu, Qin Wang, "RSS Assisted TOA-Based Indoor Geolocation"; Int J Wireless Inf Networks (2013) 20: page 157-159; DOI 10.1007/s10776-012-0198-9.
To improve the reliability it has also been evaluated to add sensors that are very local in nature. One such example is to use RFID tags. This is described in WO 2009/1 18762 A1 where ZigBee-enabled active RFID devices and a wireless sensor network (WSN) is used to design a wireless information and safety system for underground mines enabling tracking and monitoring of users and movable equipment. To improve the reliability by reducing the demand of network coverage, inertial sensors can be incorporated. One such approach where RSS and inertia sensors are joined for positioning calculation purposes is described in: Zhang Ke-Fei, et al, "Underground
mining intelligent response and rescue systems", The 6th International Conference on Mining Science & Technology; Procedia Earth and Planetary Science 1 (2009), page 1045-1048, www.sciencedirect.com. The current approaches for localisation and positioning of humans and devices in underground mines are mainly relying on WLAN, ZigBee and RFID solutions or joining two of them together (WLAN + RFID, ZigBee + RFID). However, these approaches give position accuracy in the range of 5 - 50 meters. Therefore, there is a need for a more accurate positioning system, providing more precise coordinates and a more efficient computing approach.
SUMMARY
It is an object of the present invention to provide an improved alternative to the above techniques and prior art. More specifically, the present invention introduces a model including a multiplicity of different signal sources supporting the determination of a specific location.
To achieve these and other objects, a method and a positioning system in accordance with the independent claims are provided.
The invention is based on the insight that by using several different wireless communication systems and compensating for NLOS a more accurate and versatile position of a human or device can be estimated. Also, as use of wireless systems becomes more widespread in mining facilities, these can be used for positioning purposes.
In the present invention it is proposed to use several different wireless technologies such as ultra-wideband (UWB), wireless local area network (WLAN), IEEE 802.15.4 and Bluetooth to extract different important variables such as time-of-arrival (TOA), time- difference-of-ar val (TDOA), received signal strength indicator (RSSI), bit error rate (BER) and angle-of-arrival (AOA). These variables are fed into a decision maker system to calculate and determine the current position of a human or a device. There is also
compensation for humans/devices in NLOS conditions, to obtain a high accuracy of the true position. The invention further proposes to measure acceleration and bearing from a human or device using an Inertial Measurement Unit (IMU), which may further improve the estimation of the position measurements.
According to a first aspect of the invention, a method for positioning humans and devices in underground environments using wireless signals is provided as defined in claim 1 . According to a second aspect of the invention, a positioning system for positioning humans and devices in underground environments using wireless signals is provided as defined in claim 7.
In accordance with an embodiment of the invention, positioning of humans and devices in underground environments is performed in a positioning system, the positioning system including a decision maker system. A multitude of wireless systems transmit radio signals in an underground environment. The wireless systems receive and calculate different measurement data. NLOS compensation of the measurement data is performed, if a human or device is in a NLOS condition. The measurement data is then fed into the decision maker system which estimates the correct position of the human or device using a filter. The fact that a multitude of wireless sources can be used in combination with the NLOS compensation of the measurement data enables for a more precise estimation of the position of a human or device. In accordance with another embodiment of the invention the measurement data can be received from an Inertial Measurement Unit (IMU). The IMU measures the
accelerations, angular velocities and sometimes also the magnetic field. Based on these measurements, estimates of the positions of the humans or devices can be computed even without wireless coverage. This results in that an acceptable accuracy can be obtained with fewer access points or that a higher accuracy can be obtained if the access point density is kept constant. Being able to position the devices and humans
with fewer access points is very beneficial since fewer wireless access points means less installation and maintenance costs.
One advantage with the concept of the present invention is that the safety of humans in a plant can be increased since it is possible to localise the workers to avoid dangerous areas, or to see if an area is empty before blasting, etc.
Another advantage and benefit is that the productivity in a plant can be improved. By knowing where the devices are located the production flow can be improved and more intelligent decisions can be made.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features and advantages of the present invention will emerge more clearly to a person skilled in the art from the following non-limited detailed description when considered in connection with the attached drawings, wherein:
Figure 1 shows a schematic flowchart of estimation of a position in accordance with an exemplifying embodiment of the present invention.
Figure 2 shows a schematic flowchart of estimation of a position in accordance with another exemplifying embodiment of the present invention.
DETAILED DESCRIPTION
An embodiment for positioning of humans and devices in underground environments performed in a positioning system (1 ) is shown in figure 1 . The object of the positioning system (1 ) is to track the position of a human or a device and display this information on a display unit. Devices can typically be vehicles, equipment, machinery, etc. The positioning system (1 ) comprises a decision maker system (2). The wireless systems ultra-wideband (UWB), wireless local area network (WLAN), IEEE 802.15.4 and Bluetooth transmit radio frequency signals in an underground environment. The wireless systems transmit the radio frequency signals on either the same or different frequency bands. The positioning system (1 ) is adapted so that it is possible to use the signals
individually or two or more at the same time depending on what source is available, thus imposing less strict requirements on the infrastructure.
Reference units (RUs), which are anchor points with known, fixed, locations, are placed at strategic locations for maximum coverage throughout the underground environment. The RU should contain a WLAN- and an UWB radio. A mobile unit (MU) is a small, battery driven, portable platform that is worn by a human or attached to a device. The MU should also contain a WLAN- and/or an UWB radio. The wireless systems receive and calculate measurement data by measuring the TOA (3) or TDOA and RSS (4) between the RUs and MUs via their respective WLAN- and UWB radio interface. Optionally the RUs and MUs can contain an IEEE 802.15.4- or Bluetooth radio which then can be used for receiving and calculating the measurement data. For TOA (3), the distance is estimated using the time difference between transmission and arrival of a signal. With the TDOA principle, the MU transmits a signal to a number of RUs and the time difference between arrival of the different RUs is used to estimate the position of the MU. For RSS (4) the signal strength is used to calculate the distance between the MU and the RU and once at least three distances are known the position of the MU can be estimated using trigonometric calculations. In some situations it is enough with two or even one known distance to estimate the position of the MU. For instance when the map information of the underground environment is known.
In situations when NLOS (5) occur, the positioning system will compensate by using suitable error mitigation techniques to mitigate NLOS measurement errors and discard unreliable measurements. Example of known NLOS detection techniques that can be used are: running variance, confidence metric, delay spread and change of signal to noise ratio.
The measurement data is then fed into the decision maker system (2) to estimate the correct position of a human or device using a filter based on statistical sensor fusion such as a Kalman filter (KF) or an Extended Kalman filter (EKF). The filter can also be provided with map information from a vector map comprising vectors and nodes representing possible movement paths for a human or device in the mine. The map
information can be used to constrain the position estimate to feasible areas, for instance, the mine tunnels, to improve the accuracy and reduce the number of needed wireless access points. In this case, sensor fusion algorithms like Constrained Extended Kalman filter (CEKF) or particle filters are used.
The estimated position is then presented on a display unit of for example a personal digital assistant (PDA) or a control system. Any existing wireless system infrastructure in the underground environment can be exploited by the positioning system by using it to transmit data from the RUs to the decision making system and from the decision making system to the display unit.
Another embodiment for positioning of humans and devices in underground environments is shown in figure 2. To further improve the estimation of the position of a human and device, measurements from an Inertial Measurement Unit (IMU) (6) can be used. The IMU (6) is included in the MU. Measurements from an IMU (6) can include different sensors such as accelerometers, gyroscopes, and magnetometers. The measurements from the IMU (6) can be transmitted to the RUs via the WLAN interface of the MU if there is a WLAN connection available. However, preferably the measurement data should be used locally in the MU. Hence, the measurement data is then received from wireless signals and/or from an IMU. One advantage with this is that if the wireless UWB or WLAN connections are lost, position estimation can still be performed using dead reckoning techniques, based on the IMU measurements. The main idea is then to compute the next position by extrapolating a new position from the previous position and the estimated speed and direction of travel from the IMU.
Another advantage is that in order to rely only on WLAN and/or UWB, the transmitter density has to be high; hence extra sensors are required only for the positioning. Using the IMU (6) it is possible to dead reckon for some time which means that less radio sensors are needed.
The person skilled in the art realises that the present invention is not in any way restricted to the embodiments described above. On the contrary, several modifications
and variations are possible within the scope of the invention as defined in the appended claims.
Claims
1 . A method for positioning of humans and devices in underground environments performed in a positioning system, the positioning system including a decision maker system, wherein the method includes:
- receiving and calculating measurement data from wireless signals,
- using non-line of sight, NLOS, compensation of the measurement data if a human or device is in a NLOS condition,
- feeding the received data into the decision maker system, wherein the decision maker system is estimating the position.
2. The method of claim 1 , wherein the estimation of the position includes using a filter.
3. The method of claim 2, wherein the filter is a Kalman filter, an Extended Kalman filter, a Constrained Extended Kalman filter or a particle filter.
4. The method of any preceding claims, wherein the measurement data is received from an Inertial Measurement Unit.
5. The method of any preceding claims, wherein the measurement data is received and calculated through measurements included in the group of TOA, TODA, RSS, RSSI, PER, BER, RTOF and AOA.
6. The method of any preceding claims, wherein the filter is provided with map information from a vector map.
7. A positioning system, for positioning humans and devices in underground
environments, the positioning system including a decision maker system for receiving measurement data from existing wireless signals, using NLOS compensation of the measurement data if a human or device is in a NLOS condition and for feeding the received data into the decision making system, wherein the decision making system is adapted to estimate the position.
8. A positioning system according to claim 7, wherein the decision making system is adapted to estimate the position using a filter.
9. A positioning system according to claim 8, wherein the filter is a Kalman filter, an Extended Kalman filter, a Constrained Extended Kalman filter or a particle filter.
10. A positioning system according to any of claims 7-9, wherein the measurement data is received from an Inertial Measurement Unit.
1 1 . A positioning system according to any of claims 7-10, wherein the measurement data is received and calculated through measurements included in the group of TOA, TODA, RSS, RSSI, PER, BER, RTOF and AOA.
12. A positioning system according to any of claims 7-1 1 , wherein the filter is provided with map information from a vector map.
13. A positioning system according to any of claims 7-12, wherein the positioning system is adapted to present the estimated position on a display unit.
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106197406A (en) * | 2016-06-20 | 2016-12-07 | 天津大学 | A kind of based on inertial navigation with the fusion method of RSSI wireless location |
| WO2017044265A3 (en) * | 2015-09-10 | 2017-04-27 | Cpg Technologies, Llc. | Geolocation using guided surface waves |
| CN107071896A (en) * | 2017-03-31 | 2017-08-18 | 中国矿业大学(北京) | One kind realizes colliery winding roadway object localization method using non line of sight signal |
| US10042077B2 (en) | 2016-04-15 | 2018-08-07 | Saudi Arabian Oil Company | Magnetic induction based localization for wireless sensor networks in underground oil reservoirs |
| JP2018530753A (en) * | 2015-09-10 | 2018-10-18 | シーピージー テクノロジーズ、 エルエルシーＣｐｇ Ｔｅｃｈｎｏｌｏｇｉｅｓ， Ｌｌｃ | Geographic location using induced surface waves |
| AU2022232123A1 (en) * | 2022-02-14 | 2023-08-31 | China Coal Technology & Engineering Group Shenyang Engineering Company | Moving target positioning capability testing device and testing method for coal mine |
| WO2023173729A1 (en) * | 2022-03-16 | 2023-09-21 | 中国矿业大学 | Accurate positioning method and system based on multi-source information fusion and for monorail crane in underground coal mine |
| US11835675B2 (en) | 2019-08-07 | 2023-12-05 | Saudi Arabian Oil Company | Determination of geologic permeability correlative with magnetic permeability measured in-situ |
| US11860077B2 (en) | 2021-12-14 | 2024-01-02 | Saudi Arabian Oil Company | Fluid flow sensor using driver and reference electromechanical resonators |
| US11867049B1 (en) | 2022-07-19 | 2024-01-09 | Saudi Arabian Oil Company | Downhole logging tool |
| US11879328B2 (en) | 2021-08-05 | 2024-01-23 | Saudi Arabian Oil Company | Semi-permanent downhole sensor tool |
| US11913329B1 (en) | 2022-09-21 | 2024-02-27 | Saudi Arabian Oil Company | Untethered logging devices and related methods of logging a wellbore |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2442950A1 (en) * | 2003-09-26 | 2005-03-26 | Chahe Nerguizian | Method and system for indoor geolocation using an impulse response fingerprinting technique |
| US8164514B1 (en) * | 2009-05-07 | 2012-04-24 | Chun Yang | Method and apparatus for fusing referenced and self-contained displacement measurements for positioning and navigation |
-
2013
- 2013-12-11 WO PCT/EP2013/076217 patent/WO2015086062A1/en active Application Filing
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2442950A1 (en) * | 2003-09-26 | 2005-03-26 | Chahe Nerguizian | Method and system for indoor geolocation using an impulse response fingerprinting technique |
| US8164514B1 (en) * | 2009-05-07 | 2012-04-24 | Chun Yang | Method and apparatus for fusing referenced and self-contained displacement measurements for positioning and navigation |
Non-Patent Citations (3)
| Title |
|---|
| FERIT OZAN AKGUL ET AL: "AOA Assisted NLOS Error Mitigation for TOA-Based Indoor Positioning Systems", MILITARY COMMUNICATIONS CONFERENCE, 2007. MILCOM 2007. IEEE, IEEE, PISCATAWAY, NJ, USA, 29 October 2007 (2007-10-29), pages 1 - 5, XP031232506, ISBN: 978-1-4244-1512-0 * |
| GUVENC I ET AL: "A Survey on TOA Based Wireless Localization and NLOS Mitigation Techniques", IEEE COMMUNICATIONS SURVEYS, IEEE, NEW YORK, NY, US, vol. 11, no. 3, 1 October 2009 (2009-10-01), pages 107 - 124, XP011272510, ISSN: 1553-877X, DOI: 10.1109/SURV.2009.090308 * |
| JAVIER PRIETO ET AL: "Adaptive Data Fusion for Wireless Localization in Harsh Environments", IEEE TRANSACTIONS ON SIGNAL PROCESSING, IEEE SERVICE CENTER, NEW YORK, NY, US, vol. 60, no. 4, 1 April 2012 (2012-04-01), pages 1585 - 1596, XP011433253, ISSN: 1053-587X, DOI: 10.1109/TSP.2012.2183126 * |
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| CN108351399A (en) * | 2015-09-10 | 2018-07-31 | Cpg技术有限责任公司 | Use the geo-location of lead schedule surface wave |
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| US10151851B2 (en) | 2016-04-15 | 2018-12-11 | Saudi Arabian Oil Company | Magnetic induction based localization for wireless sensor networks in underground oil reservoirs |
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| CN106197406B (en) * | 2016-06-20 | 2019-06-25 | 天津大学 | A kind of fusion method based on inertial navigation and RSSI wireless location |
| CN106197406A (en) * | 2016-06-20 | 2016-12-07 | 天津大学 | A kind of based on inertial navigation with the fusion method of RSSI wireless location |
| CN107071896A (en) * | 2017-03-31 | 2017-08-18 | 中国矿业大学(北京) | One kind realizes colliery winding roadway object localization method using non line of sight signal |
| US11835675B2 (en) | 2019-08-07 | 2023-12-05 | Saudi Arabian Oil Company | Determination of geologic permeability correlative with magnetic permeability measured in-situ |
| US11879328B2 (en) | 2021-08-05 | 2024-01-23 | Saudi Arabian Oil Company | Semi-permanent downhole sensor tool |
| US11860077B2 (en) | 2021-12-14 | 2024-01-02 | Saudi Arabian Oil Company | Fluid flow sensor using driver and reference electromechanical resonators |
| AU2022232123A1 (en) * | 2022-02-14 | 2023-08-31 | China Coal Technology & Engineering Group Shenyang Engineering Company | Moving target positioning capability testing device and testing method for coal mine |
| WO2023173729A1 (en) * | 2022-03-16 | 2023-09-21 | 中国矿业大学 | Accurate positioning method and system based on multi-source information fusion and for monorail crane in underground coal mine |
| US11867049B1 (en) | 2022-07-19 | 2024-01-09 | Saudi Arabian Oil Company | Downhole logging tool |
| US11913329B1 (en) | 2022-09-21 | 2024-02-27 | Saudi Arabian Oil Company | Untethered logging devices and related methods of logging a wellbore |
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