Locating underground markers
Inventors
Appleby, Rodney • Thiel, David • Maggs, Michael • Spathis, Alex
Assignees
Griffith University • Orica Australia Pty Ltd • Orica International Pte Ltd
Publication Number
US-10123157-B2
Publication Date
2018-11-06
Expiration Date
2033-10-10
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Abstract
A process for locating underground markers, including: transmitting signals through the ground between markers in the ground; and determining locations of the markers based on the transmitted signals.
Core Innovation
The invention relates to a process and system for locating underground markers by transmitting signals through the ground between the markers and determining their locations based on these transmitted signals. The markers form nodes in an ad hoc communications network, enabling communication between markers even when they are buried deeply and out of direct range of a base station, through multi-hop signal relaying among markers.
This method addresses the problem of identifying the post-movement locations of underground structures, such as ore bodies during mining blasting operations, where ground movement can displace ore boundaries. Accurate post-blast ore boundary identification is critical to reduce ore dilution, which results from ore loss or waste processing inefficiencies caused by incorrect knowledge of ore boundaries after ground movement.
The system includes markers equipped with transmitting and receiving capabilities, sensors, and power supplies, capable of acting as network nodes. The process uses signal properties like strength and transmission times to determine distances between markers, employing trilateration and iterative model fitting to accurately locate markers in three-dimensional space. The system also accounts for variations in ground properties and uses anchor markers in stable ground areas to improve location accuracy.
Claims Coverage
The patent discloses nineteen claims including processes and systems for locating underground markers using signal transmission, measurement, and trilateration methods. The claims cover inventive features relating to signal transmission in ad hoc networks, determination of marker locations, ground property assessments, power level control, sleep modes, user interfaces, and movement monitoring.
Locating underground markers using signal transmission, reception, and trilateration
Transmitting signals between underground markers arranged as nodes in an ad hoc communications network, determining received signal properties including strengths or transmission times, determining distances based on these properties, using trilateration, iterative error minimization between modelled and determined distances, and generating a 3D map of marker locations.
Incorporating end conditions in iterative location determination
Using a minimum error threshold and/or a maximum number of iterations to terminate the iterative process of refining modelled locations.
Using signal directions and triangulation
Determining marker locations based on directions of received signals, including directions of arrival, and using triangulation methods based on these signal directions.
Utilizing marker movement data for location determination
Representing marker movements within transmitted signals and determining current marker locations using pre-movement locations and marker movement data.
Using geo-location and displacement data in location determination
Including geo-location data from coordinate systems or GPS and displacement data such as velocity and acceleration in determining marker locations.
Identifying markers via transmitted signal identifiers
Using unique identifiers carried in each transmitted signal to identify corresponding transmitting markers.
Using anchor markers with negligible ground movement
Employing anchor markers in stable ground areas as preferred modelled locations to aid in location determination during ground movement.
Determining and using ground property values via transmitted test signals
Transmitting test signals to determine values of selected ground properties by analyzing received test signal properties and selected test locations, using statistical average or median values for calculation.
Adaptive emitter power level control
Allowing emitting markers to select transmission power levels to ensure received power levels at receiving markers are below saturation, using feedback signals for adjustment.
Sleep mode activation via activation signals
Enabling markers to enter sleep mode before transmission and be reactivated upon receiving an activation signal transmitted through the ground.
Generating three-dimensional displays and using sensor data during excavation
Producing 3D displays for user interfaces, receiving sensor data such as temperature and pressure from markers, and using determined location data in excavation operations or for indicating material flow through plant equipment.
Monitoring ground movement using pre- and post-movement location data
Accessing data on pre-movement and post-movement marker locations to generate movement data indicating ground movement, including applications to ore movement during blasting.
System configuration for underground marker location
A system comprising at least one pair of markers transmitting signals through ground, marker transceivers determining signal properties, and a computing device determining marker locations in an ad hoc network by trilateration and iterative model fitting until an end condition is met.
The claims comprehensively cover both the process and system aspects of locating underground markers by signal transmission and reception in an ad hoc network, determining distances and locations using trilateration and iterative fitting, including handling ground property variations, marker identifiers, power control, sleep modes, and applications to monitoring ground movement, particularly for mining purposes.
Stated Advantages
Provides rapid and accurate three-dimensional location determination of underground markers, including deeply buried ones, without needing to move surface equipment.
Enables near real-time mapping of post-blast ore boundaries to reduce ore dilution and improve mining efficiency.
Allows use of multiple signal properties and ground property modeling for improved location accuracy.
Supports multi-hop communication in an ad hoc network to extend range and flexibility of the monitoring system.
Includes power management features like adaptive emitter power level and sleep mode to preserve device battery life.
Facilitates integration with mining equipment and user interfaces for operational decision-making and real-time excavation guidance.
Documented Applications
Monitoring movement of ore bodies during blasting in mining operations to identify post-blast ore boundaries for selective mining.
Generating three-dimensional geological maps of underground markers to assist mining engineers in excavation planning.
Providing location data to mining plant equipment such as diggers for improved excavation accuracy and ore recovery.
Monitoring the flow of excavated material through processing plant equipment by tracking markers embedded in the rock.
Detecting ground movement by comparing pre- and post-movement locations of markers for operational and safety insights.
Interested in licensing this patent?