IM 2021 October 21 | Page 59

MINING DRONES consumer-grade drone equipment . While this kit may be perfect for taking basic photos and videos , it fails to consistently deliver highaccuracy survey and engineering data day-afterday .”
Clark says DLTI has built long-term relationships with aviation regulators , such as the South Africa Civil Aviation Authority , and focused on offering Beyond Visual Line-of-Sight drone operations that come with experienced pilots able to capture valuable data .
“ The ability to utilise longer-range aircraft essentially drives down the acquisition cost per hectare , ultimately reducing the customer ’ s end cost ,” he said .
In LiDAR applications , specifically , the development of significantly lighter ( around 750 g ) and better integrated payloads has allowed DLTI to offer fixed wing vertical take-off and landing UAVs that can cover over 1,000 ha in a single 90-minute flight .
Clark added : “ While the LiDAR sensor on DLTI ’ s drones may not yet be as sophisticated as the sensors on manned aircraft , the fact that we are flying lower to the ground delivers very comparable results and accuracy as manned LiDAR solutions , achieving between 5-10 cm vertical accuracy .”
This benefit has shone through in some of the recent contract awards , with Newmont ’ s Ahafo gold mine selecting a drone-based LiDAR solution from DLTI to create an accurate 3D model of the earth and its surface characteristics to map new areas for the mine and mitigate potential risks prior to mine expansion construction commencing .
Clark said in that contract announcement press release : “ We are seeing increased demand to use our LiDAR capability to create ‘ digital elevation models ’ that allow companies to see below thick forest and other surface vegetation and more accurately determine site suitability for certain types of infrastructure and how a site can be used .”
And where manned LiDAR providers would require a large scanning area to carry out a survey , drone-based LiDAR can provide a costeffective option for smaller projects under 10 sq . km , according to Clark .
“ Clients would typically have to wait until a larger project was conducted in the region by manned aircraft before they would get their data ,” he said . “ DLTI ’ s drone solution enables these customers to access their terrain models sooner when compared to manned LiDAR .”
Looking at how the market for drones will evolve from here onwards , Clark was adamant that a one-size-fits-all drone solution was unlikely to solve all the mining industry ’ s needs .
“ The industry will adopt more drone and robot technologies , however , instead of one piece of kit being able to do it all , you ’ re going to have multiple specialist drone and robots performing a single application very well ,” he said .
Ready for the transition
BHP ’ s Olympic Dam mine in South Australia was an early adopter of Emesent ’ s mobile LiDAR system and the mine has since gone on to trial new Emesent capabilities as they are developed and before public release .
Emesent ’ s flagship product , Hovermap , is a LiDAR mapping and autonomy payload that combines advanced collision avoidance and autonomous flight technologies to map hazardous and GPS-denied environments . It can be used in walking scans , or mounted on a vehicle or drone , to map challenging , inaccessible areas .
This flexibility has been leveraged by Olympic Dam over the years .
The mine ’ s survey and production teams began using a drone-mounted Hovermap to scan stopes in February 2019 , replacing its conventional cavity monitoring system .
According to Evan Jones , Principal Geotechnical Engineer at BHP , speaking in an Emesent webinar , the geotechnical teams soon realised the benefit of the system and began to use the LiDAR data to improve their understanding of the operation ’ s Southern Mine Area rock mass characteristics ; research failure mechanisms within stopes ; and re-evaluate design assumptions through “ back-analysis ”.
Currently the Olympic Dam team uses Hovermap to scan stopes after almost every blast sequence and at regular intervals throughout the lifecycle of each stope . This allows them to : n Identify any issues early on in the process ; n Accurately measure in-stope stock volumes ; n Conduct stope stability analysis ; n Calculate over-break and under-break and final stope shape ; and n Monitor the backfill .
At the same time , the company is leveraging Hovermap ’ s abilities at the drawpoint to monitor movement , while inspecting the orepass and carrying out inspections of retired infrastructure are also within Hovermap ’ s remit .
“ The Hovermap data provides insights to help BHP improve confidence in the drivers of stope stability , and to develop informed responses to issues ,” Dr Stefan Hrabar , Emesent CEO and co- Founder said .
Olympic Dam is just one of over 60 mines across the world using Hovermap , with many of these operations taking advantage of its plugand-play capability to transition from drone , to vehicle , to walking scan with ease .
BHP Olympic Dam ’ s survey and production teams began using a drone-mounted Hovermap to scan stopes in February 2019 , replacing its conventional cavity monitoring system
It has proven Autonomy Level 2 functionality that allows operators to autonomously fly a drone beyond line-of-sight and communication range – even in challenging GPS-denied environments . This could see operators fly an entire mission – from take-off to landing – using a tablet .
This was recently put to the test in a proof-ofconcept flight conducted at an “ ultra-deep ” Canadian hard-rock mine all the way from Australia , with the unit piloted from take-off to landing by Emesent founders Dr Hrabar and Dr Farid Kendoul using standard online remote collaboration tools and Emesent ’ s Autonomy Level 2 feature .
The automation also extends to the on-board processing capacity of Hovermap , enabling operators to receive a streamed 3D map in almost real time .
Emesent has been integrating Hovermap data with many other mining software providers in recent years . Collaborations with Deswik and Datamine are two notable integrations .
The latest development at Emesent saw Hovermap become plug-and-play compatible with the Zoe aircraft from Acecore Technologies , a drone platform able to handle harsh environments and carry a large payload .
The integration will see the Zoe unit able to carry both Hovermap and a full-frame gimballed camera , “ making the Hovermap-Zoe combination a great solution for aerial inspection and mapping work ”, Peter Dickinson , Head of Product Management for Emesent , said .
A key enabler for the integration was making Hovermap compatible with the open-source ArduPilot flight control platform , a flight controller installed in over one million vehicles worldwide . This sees Hovermap ’ s autonomy integrated with ArduPilot at its core , providing full control of all elements of the flight controller and providing a robust solution for flights beyond-line-of-sight and communication range , Emesent said .
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OCTOBER 2021 | International Mining 55