UNDERGROUND LOAD & HAUL
challenges and benefits in their 25 minutes up on stage , including challenges such as the lack of initial training available , limited parts compatibility , several part failures and issues
with ground engaging tools ; and benefits such as
increased service intervals , increased component life , increased hydraulic system life , reduced tyre wear , reduced hydrocarbon use , reduced numbers of moving parts and reduced driveline shocks .
Singleton and Flynn also talked up the “ different set of advantages ” offered up by
diesel-electric technology compared with battery or existing diesel technology . This included lower running costs than diesel alone , the provision of
benefits of full electrical control and drive
efficiency , lower emissions and less diesel burn .
They also said the diesel-electric loader provided the ideal platform for adapting autonomous systems .
And , of course , there were several operational
advantages to having these diesel-electric loaders in the fleet , such as improved operator comfort / reduced noise , higher tramming speeds and lower heat generation .
Nerospec ’ s automated mucking revolution
Nerospec SK has – by its understanding – developed a world first in the market : a true fully autonomous underground loader that carries out a full cycle with no manned supervision at all .
Although this specific product solution was developed together with GHH , the Nerospec automation solution remains totally OEMagnostic and can , it says , be implemented on any OEM ’ s equipment and optimised and customised according to specific customer and application needs .
Using its mission planning system for the shift , the loader finds its way to the different mucking locations . Nerospec CEO , Dr Eric Pohlmann , told IM that this self-navigation through the mine drifts is nothing new for autonomous LHDs but what is distinct is that this has been carried out in a room and pillar environment , which makes navigation more challenging .
Then comes the most difficult part , and that is the mucking itself – and in the potash-salt mines where the autonomous LHD is running , this is from a very wide stope / face area of up to 10-12 m across . So , the machine needs to have a strategy on how to effectively load that . This involves some side loading from each side , plus centre loading to account for the mass distribution of the muckpile . There is also variation depending on the shape of the muckpile , so there is no set strategy with the LHD needing to adapt every single time .
This is what the algorithm that Nerospec SK has deployed on the machine can do . Pohlmann said : “ We have been putting a lot of energy into this autonomous mucking strategy development
algorithm , together with the AMTC centre , from the Universidad de Chile , and GHH . It has been working very well and is able to reposition the machine if it is not spotted in the right place for optimum muckpile entry .”
Nerospec SK ’ s target has been to achieve 70 % of the nominal capacity of the machine , which is a GHH SLP-14H . “ We have been doing , on average , 77 % so have been overachieving on our targets – and doing this quite consistently ,” Pohlmann said . Then the machine autonomously trams to dump the load into the underground crusher or ore pass – there is absolutely no operator intervention , Nerospec says .
Pohlmann continues : “ I would say there are three highlights that make it an industry first – it is a retrofit underground solution ; then there is no human supervision required ; and , finally , it is autonomous and does not require a heavy-duty data or communications infrastructure like Wi-Fi , LTE or leaky feeder . It was designed this way as in the soft-rock mines where it is operating the active mining front progresses quite quickly , so following it with a lot of network infrastructure needs would be a big challenge .”
Nerospec SK ’ s strategy is to offer the automation system as a retrofit – an area where it is already highly experienced given its main business is providing vehicle intervention controllers for deployment of EMESRT Level 9 collision avoidance systems , and all the