High-altitude drilling, extreme heat, cold and wet, and difficult terrain, have all been conquered by Epiroc's surface drill automation engineers, working closely with customers in many parts of the world. As reported in Drill automation leader unlocks door to next benefit levels, Epiroc customers from BHP in Australia to Newmont in Canada and Boliden in Sweden, have reported significant productivity, cost and safety benefits from auto-drill deployment over the past few years.
"If the drills don't perform, the trucks are going to run empty," says Epiroc Australia surface division business line manager, Alex Grant, who heads a team overseeing introduction in the country's coal industry of state-of-the-art Epiroc Pit Viper autonomous production drills.
"We're successfully running a fully autonomous rig at a coal mine on [Australia's] east coast, which I believe is a first in the industry," Grant says.
"That is, we have a drill completing a loaded drill pattern at the same, or better, productivity level as a manned rig, which was the challenge set for us.
"The next step is to run two autonomous rigs side by side, which puts us further ahead of the game.
"We are seeing a very high success rate with [Epiroc's unique] ARC [auto rod change] - the limiting factor for these drills in the past - which is working very well with our AutoDrill 2 technology and the inbuilt smarts in our Rig Control System [RCS]."
Multiple rigs working autonomously on multi-pass patterns is understood to be close.
"The ability to literally load up a full drill pattern onto the drill rig, press the go button on the drill rig and let it do its thing, and it will execute the full drill pattern without anybody intervening to do anything unless of course there is a fault or maybe there's a challenge down the hole that the drill can't figure out, or refuelling - this is something the industry had shown it is ready to take full advantage of now," Grant says.
"But the technology, and the software, continues to evolve at a fast pace.
"In our early autonomous drill algorithms, it was more like cruise control mode where you told the drill what it was going to do and it did that. These days the drill works out what it's drilling into, and how much air it needs to put down the hole, or how much water it needs to put down the hole, to cope with what's going on in-hole, and whether it has to go through a cleaning cycle, or not."
Epiroc product engineer Peter Miller, one of the lead architects of the company's RCS machine intelligence ‘platform', says the company knew from its extensive field experience and consultation with customers that its new system "would have to be able to perform out of the box with improved speed, quality, and efficiency and be truly hands off for the majority of operation".
AutoDrill2 delivered a "much more intelligent system capable of adapting to a bigger range of ground conditions".
"With the second generation system we reduced operator settings by 90%.
"With the transition to our next generation system RCS5, AutoDrill is fully incorporated into the drill [control] screen with the operating ranges overlayed on the drill gauges to give better operational awareness.
"We continue to improve the system with every software release.
"Our strategy is not to tune the operating envelope to differing conditions at a specific customer but to expand the operating envelope so the system has an ever growing bag of tricks to apply to different situations.
"This means we leverage our worldwide experience to benefit all of our customers."
Rod changing is a highly repetitive part of multi-pass drilling. Automating the rod-handling carousel, and synchronising precise rig positioning on the ground to maintain consistent machine operation to plan on uneven pit floors, were among the key challenges for Epiroc's automation engineers as they contemplated production drilling in coal mines.
The patented ARC technology, integrated into Epiroc's AutoDrill 2 for multi-pass automation, reliably and efficiently adds rods to reach target depths. Rods are removed during retraction and hole cleaning.
"We have moved from fixed set-points to ranges where the system figures out the exact set-point in reaction to ground conditions in real time without an operator having to tell it that the ground has changed," Miller says. "Jam prevention" continuously monitors ground thresholds to prevent bogging before it happens and initiates back-reaming to break free from obstructions, while the rig's "hole stabilisation" control varies retraction cleaning time based on ‘experience' and can initiate pre-emptive cleaning again based on drilling condition awareness.
Grant says an automated production drill can switch to a more conservative drilling mode if conditions require it.
"To make this work we are using the smart functions on the drill rig that are already there," he says.
"Since we developed these functions over several years, and refined them with a lot of customer feedback, we have an excellent understanding of how to incorporate them in autonomous mode in a wide range of conditions."