Rise of the machines

It has been three years since BHP Billiton embarked on its drill automation journey. By the end of this year all the blast hole drilling on all its Western Australian iron ore mines will likely be done autonomously.
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Atlas Copco has helped automate BHP Billiton's iron ore blast hole drills

Noel Dyson

Where other companies started with autonomous haulage, BHP chose to automate its drilling first.

That, BHP mine automation readiness superintendent Mark Miles said, was more of a coincidence than anything else.

In some ways though, going after autonomous drilling and getting all of the optimisation benefits from that will bring a miner more bang for its buck.

According to Miles the company enjoyed roughly a 20% improvement in the optimisation of its drills.

That optimisation has the potential to flow right through the system – more so than an optimisation gain with autonomous haulage would do. If the blast is optimised, the digging, loading and hauling improve. Fragment sizes are better so crushing works better and so on.

Atlas Copco won the contract to convert 18 of BHP’s drills to autonomous operation in June. That was to go with the three rigs it had already converted.

BHP is using Atlas Copco Pit Viper 271 rotary blast hole rigs at its WAIO sites. Those drills cut a 250mm diameter hole and can drill down to a depth of about 13-14m.

That Atlas Copco was already providing blast hole rigs to BHP’s WA iron ore mines no doubt helped, however, Miles said the company undertook an extensive process to make sure it had the best automation option.

Atlas Copco had some automation runs on the board. It was involved with the early days of Rio Tinto’s automated drill program. In that case Rio Tinto went down a different path.

However, the Swedish mining equipment maker had developed a healthy suite of automation offerings in its own right.

Its Rig Control System – the electronic backbone of the rig – allows for an existing Pit Viper 271 to be retrofitted with the automation package.

That is an important consideration for miners because it reduces their cost of entry into the automation space.

Atlas Copco had previously been involved in a two-year autonomous drilling trial at BHP’s Yandi iron ore mine. 

During that trial drills were operated autonomously for more than 15,000 hours, drilling more than 1 million metres.

Atlas Copco drilling solutions business line manager Dustin Penn said the company had delivered 24 Pit Viper 271s to BHP.

“They had the base RCS platform that allowed them to have the capability to upgrade to fully autonomous operation,” he said.

After the first autonomous machine started being trialled in 2014 BHP took the decision to upgrade another two machines to fully autonomous operation in 2015.

“From that point on they’ve been running the full mining production drilling at Yandi with fully autonomous drills,” Penn said.

BHP is in the process of rolling out the autonomous drilling program across its five Pilbara iron ore mines: Yandi, Mining Area C, Jimblebar, Mt Whaleback and Eastern Ridge.

The contract Atlas Copco won will take the autonomous Pit Viper fleet to 20 rigs and that is expected to be enough. 

The drills operate autonomously, tramming to each hole, before levelling themselves and preparing to drill. 

Each hole is then drilled exactly to the parameters set out in the drill plan.

Constantly throughout the drilling process the rig is providing feedback such as torque pressure, rotation speed and downward pressure. This can give some indication of the type of material being encountered or – just as important – not encountered in the case of a void.

Should the rig encounter difficulties, an operator can take control of it through a teleremote hook up and help get it back on track.

At the moment that teleremote operation is being done from site.

At Yandi, there is one operator overseeing three drills. 

While the teleremote back-up has been on site it does not always have to be. BHP is in the process of moving the teleremote operation back to its Integrated Remote Operations Centre in Perth.

Miles said there had already been trials conducted and the process of moving to the iROC was pretty advanced.

One of the benefits of automation is extended up time for the rigs. There robot rigs do not need to stop for lunch or smoko breaks. Shift changes are a lot quicker too because there is no need for an operator to drive out to where the rig is. 

“On their best days they’ve had 11 and a half hours of drilling in a 12 hour shift,” Penn said.

“Previously they were doing about eight and a half hours in a 12 hour shift [with human operators].”

To get the most out of the machines requires good coordination with the fuel, water and other maintenance services.

Miles said the trick was to coordinate the replenishment of fluids on the machines and any maintenance with whenever the machine was stopped.

As expected there have been technological challenges to getting the automation in place.

Key among these is wireless network communications. There has to be constant contact with the rig for the autonomous system – or even the teleremote one – to work.

Miles said making sure there was connectivity for the machines could be challenging, even in open cut mines.

Then there are the mine specific systems to factor in. 

Atlas Copco, realising each customer would likely have bespoke communications networks, had to devise a system that was network agnostic.

“BHP wanted specific network radios,” Penn said. “If we go to another site they may have different radios.

“We don’t require any specific brand of radios and switches to make the system perform.”

Penn said the autonomous system was pretty much a bolt-on one these days, although there were tweaks required to make it perform optimally for each customer’s environment.

He said there had been total collaboration between BHP and Atlas Copco to get the autonomous drilling program in place.

“With each new software update we roll out we’re getting even bigger efficiency gains,” he said.

“Once you start autonomous you have to start learning how to use it and maximise it.”

One of the key players in Atlas Copco’s automation program is automation manager Dr Adrian Boeing. After completing his PhD in robotics, Boeing worked in Germany with automotive robots before moving into the mining space.

There he worked with BMW and Volkswagen on autonomous driving systems such as lane change assist.

In the Atlas Copco technology development sphere there are three key areas: Sweden, Australia and Garland, Texas.

Boeing said a lot of the core software development was done in Sweden and there was a technology team in Australia that supported customers using that technology.

“Then there is a factory and support facility in Garland, Texas where a lot of the engineering is done,” he said.

While there is a lot of work still being done on the technology, there has also had to be work done on the people side of the equation.

Boeing said the people issues were among the biggest challenges when it came to automation.

“One of the big challenges is having people understand how to work well with the machines,” he said.

“There is a perception the autonomous drills should be able to do everything themselves.

“But to get the most out of the machines you have to get the robots to do what they do well, dull, repetitive tasks, and let humans do what they do best, such as analysing and interpreting things.” 

Miles said in his view people were the core of everything.

“You can have all the technology but if people don’t want to use it they won’t use it,” he said.

“There are three pillars to this: people, technology and process. You need all three of these.

“You have to take a bit more of a disciplined approach in the mining business.

“Automation requires things to be done in a set way.” 

Boeing said the Atlas Copco autonomous drills were an adaptive system rather than a learning one.

“The way it gets smarter is when we give it software updates,” he said. 

Automating blast hole drills is just one part of the future mining story of course.

Autonomous haulage at surface is becoming more common and it is becoming more widely used underground. 

However, automation is not the only way to reach the aim of mine optimisation.

Atlas Copco vice-president global technology operations Joe Farrugia said while automation was helping miners optimise their operations, machine integration would be the next big gain.

“That means machines will start talking to each other,” he said.

“If you have a crusher that is pretty well full the truck and loaders will stop digging and producing until it has space again.

“Or machines will start speeding up or slowing down by themselves depending on the bottlenecks in the operation.”

Farrugia said it was all about driving costs down and driving performance up.

“We believe that by doing that we are going to see resources mined that never would have been mined in the past,” he said.

“We have current miners that will lower their own input costs.”

While the autonomous drills program is at the surface, Atlas Copco is doing a lot of work around bringing automation to the underground realm.

An immediate benefit is reducing the number of people working underground, which brings an immediate safety benefit.

One Atlas Copco development for underground is Truck Assist, a software package that “teaches” a mine truck a haul route.

“You get the software and you drive the truck through a drift or a stope and it ‘sees’ the tunnel or stope and remembers the path you’ve taken it on,” Farrugia said.

“Then we have the wall guidance system. That’s more like driver assist.”

Farrugia said there were four stages to going to full automation.

The first is to monitor what is going on. From there it moves to taking control of one or two machines remotely. Once that is done the next step is to optimise the operation. Only then can full automation occur.

However, he believes full automation, in the underground space at least, will only appeal to certain types of operation.

“Full automation is really for large block cave mines,” Farrugia said.

“For open stope you really just need on machine automation where it will assist the driver or the operator.”

There are some operations, however, where the ore veins are so rich and well defined that air-leg drilling is the most economic and effective way to produce.