As mines around the world implement autonomous systems into their operations, the importance of establishing controls to maintain the safety and security of personnel working alongside these systems is critical. Nicholas Kenny speaks with Chirag Sathe, a mining automation expert and co-author of the Global Mining Guidelines Group white paper “System Safety for Autonomous Mining”, on how mine operators can ensure mine safety while integrating this developing technology
Automation in mining offers huge potential for the industry, and one of the biggest benefits it can provide is increasing on-site safety. Removing personnel from hazardous jobs or areas can reduce the risk of injury, and automation, at its most basic level, literally removes the need for a direct human presence on these tasks. In the past decade, the mining industry has made considerable leaps forward in embracing this burgeoning technology, mostly focused around the mobile mining area – specifically, vehicles like haul trucks, water carts and light vehicles. Process plant automation, of course, has been carried out in the chemical process industry for the past 40-50 years, so the concept itself is far from new.
The automation of haul trucks has been particularly successful and seen considerable investment as a result, due in part because it involves the most people in its operation. Each haul truck can operate on a 24-hour basis, requiring four or five drivers on rotating shifts. Long shifts can lead to driver tiredness and potentially cause accidents and injuries, which is part of why automating these vehicles was of such importance to the industry. At the same time, the operation of haul trucks contains comparably fewer variables than that of other vehicles or equipment in mining, such as diggers, dozers and excavators, which made the automation process easier to develop.
While automated systems offer great benefits in improving on-site safety, questions arise over what challenges they can pose to safety at the same time. Even when certain vehicles and their processes are automated, that doesn’t mean that human workers are removed from the mine site entirely. Many jobs are unsuited to automation or are currently too complicated or expensive to automate. For the foreseeable future, then, any mine that implements automation will be doing so alongside human beings, and that can create its own challenges in terms of safety.
“When we’re talking about automation, what people forget is that we are only automating autonomous trucks. There are a lot of other vehicles around these trucks that are driven by people,” says Chirag Sathe, a mining automation expert and co-author of the Global Mining Guidelines Group (GHG) white paper “System Safety for Autonomous Mining”. “So, it’s a semi-autonomous environment – there can be a lot of human-machine interaction.”
The three pillars of implementing autonomous systems
This crossover can create new risks in terms of safety, which is why mining operators need to take care and consider what the key factors are when introducing an automated system – which Sathe breaks down into three main pillars: “people, process and technology”.
Of the three pillars, the first – people – presents the most challenges for mining operators, Sathe says. If mining personnel are not properly trained to work with automated systems and to understand how these systems function, it can increase the risk of accidents. “In the past, anybody could drive a truck, or at least get a licence to drive, but now it’s totally different,” Sathe notes. “[Haul trucks are being] controlled from a central control room, nobody’s driving – and the trucks are operating on site, maybe 1,000km away. There a limited labour pool available, so it’s going to take time – you can’t get trained people overnight, you have to invest in it.”
With regards to the second pillar – process – the challenge that mine operators face lies not only in changing the ways in which they operate, but also in how they think about their operations. For example, when an autonomous truck breaks down, a new system has to be put in place to retrieve it. Previously, there would be a driver in the truck, who would just call maintenance and ask for help. When an autonomous truck breaks down, it sends out a signal, and there has to be a process in place to take over the broken-down truck.
Finally, the third pillar – technology – means that the system should be fit for purpose. Mining is carried out in very harsh environments, so whatever technology the industry deploys has to be able to withstand the challenges of its surroundings and the tasks it has to carry out. Sathe notes that, in mining, original equipment manufacturers (OEMs) are the ones responsible for developing autonomous technologies, with mining companies as the end users.
It’s taken time for these two groups to gain a better understanding of each other – for OEMs, that means understanding the requirements of their end users, and for mining operators, it involves understanding the requirements to successfully adapt autonomous products to fit within a mine’s processes. “With more and more experience of using these technologies, I think that gap is bridging – but it’s still there,” Sathe warns, though still remaining optimistic on the matter.
Of course, it’s still early days in many ways. It was only in 2008 that the first automated haul truck was introduced in the form of Komatsu’s Autonomous Haulage System (AHS), which was implanted at Codelco’s Gabriela Mistral copper mine in Chile. From there, it first reached Australia when Rio Tinto introduced automated trucks to its Yandicoogina iron ore mine in the Pilbara region of Western Australia in 2012, following a multi-year, five-truck trial in its West Angelas mine. That was a mere decade ago – a drop in the ocean that is the history of mining – so automation is still very much in its nascent stage, while also being very effective at the tasks to which it has been put to work.
It’s also worth noting that it’s really only haul trucks that have seen widespread use of automation across the industry – for other parts of the mining vehicle fleet, such as graders, loaders dozers and more, it’s going to take longer still. Their operations are considerably more complex than those carried out by haul trucks. “That’s where the end user and product developer talking to each other and helping to solve the problem will be the most beneficial,” says Sathe.
The system safety approach
So how, then, can mining operators look to ensure the safety of their on-site personnel working alongside autonomous vehicles and equipment in semiautonomous environments? Sathe sought to answer this question in the white paper that he co-authored for GHG – “System Safety for Autonomous Mining”. The paper looked to increase awareness of the system safety approach and the advantages that it can offer within the mining industry and OEMs.
“Normally, when automation is talked about, even in robotics, the first thing they say is to have functional safety analysis. However, when we look at mobile mining automation, functional safety is not applicable,” explains Sathe. “And that’s where there was the biggest issue between OEM and the end user – because of the lack of understanding or a lack of applicability of functional safety standards.”
Functional safety provides a framework of systems and established practices that offer confidence when delivering and maintaining safety-related control measures. However, it is unsuitable for many mining processes as it does not adequately cover systems that are non-deterministic – where the output cannot be predicted because there are multiple possible outcomes for each input, including those reliant on human behaviour or interacting with humans.
If functional safety doesn’t apply to this area, then what can the industry use instead? This is where system safety comes in, Sathe explains. System safety is a view of safety that extends beyond the machines to consider the complete system – the three pillars that Sathe laid out: people, process and technology. “You have to take a holistic view of the whole process of the automation. System safety allows us to look at all these three together,” he adds.
The goal of system safety is to identify, analyse, reduce or control risks associated with hazards to safety throughout a system’s lifecycle. System safety enables mining operators to look at scenarios such as what happens when the autonomous technology fails – what controls are in place, how personnel have been trained to respond, and so on. From there, a mining operator would review their risk for the scenario in question.
The need for a system safety approach came about in the middle of the 20th century as the systems used in industries such as nuclear power, civil aviation, defence and space became increasingly large and complex. Testing and learning from experience can only provide so much information with regard to maintaining operational safety, and the lack of consideration given to the interactions between multiple subsystems increases the risk of unexpected failures. Sathe points out that system safety can be invaluable when looking at the human-machine interface. In mining, as he’s noted previously, much of the autonomous technology at play operates in semiautonomous areas. System safety can help address how humans interact with autonomous systems. “If you only look at the functional safety, the people part is excluded,” Sathe notes. “And that’s where mining operators make the biggest mistake of saying, ‘Oh, yeah, our system is safe enough’. By not including the presence of human beings interacting with your autonomous technology, you open up your processes to unnecessary risks.”
The call for communication
Another challenge for mining operators can occur when they use automated equipment from multiple suppliers, but a system safety approach can help with that too. Similarly, with non-deterministic challenges like sensor limitation or degradation – which can lead to incidents where autonomous equipment may not be able to properly detect nearby objects or people – a system safety approach can help evaluate risks and responses. As an example, Sathe lays out a scenario where multiple OEM support systems are in place in a semi-autonomous mining site. There is an autonomous system in place to manage autonomous haul trucks, but at the same time, there are manual human-driven vehicles on site. These human-driven vehicles may have a driver-fatigue system or a collision awareness system installed. Those systems need to be able to function alongside the autonomous haul trucks, but have been supplied by different OEMs.
“Integration of interoperability of those systems is a big issue,” says Sathe. “How [do] we bring all these different technologies together and not increase risk due to one technology not talking to another? If we have to do a system safety analysis, then we need information from all these OEMs – or they have to already be working together [to ensure interoperability].”
When it comes to improving safety, Sathe believes that the mining industry should operate like airlines, in terms of how they share information with their competitors to the benefit of all involved. “The process of landing an aircraft is fundamentally the same as if you’re landing in London Heathrow or Los Angeles, or anywhere else in the world,” he says. “That’s how it should be, from a system safety point of view – we should be able to talk freely to improve safety within the mining operations.”
As autonomous vehicles and technologies are only going to become increasingly present in mining operations in the coming years and decades, Sathe believes that there is a huge need for a system safety standard operating at a higher level across the industry. Currently, there is a standard in place for autonomous passenger vehicles – ISO 26262 – but it only applies to vehicles where a driver is in the seat. There’s nothing at that level for autonomous, driverless haul trucks.
“That’s the need of the hour and the industry should come together to support it, but the mining industry is just one small part [of the puzzle],” says Sathe. “To me, a system safety approach should be agnostic to where it is applied, because it’s a process – it’s not about functional safety. We’re going away from the quantitative and pushing that it’s more about the qualitative approach.”
This article first appeared in World Mining Frontiers magazine.