Autonomous offroad trucks at the Brucutu mine have moved 100-million tons of material since the implementation of autonomous hauling in 2016, and Brazilian major Vale says that the mine’s safety and environmental performance have improved.

In the five years with vehicles without an operator in the cab, there were no accidents caused by autonomous trucks, fuel consumption has reduced, and the mine’s productivity has increased, the iron-ore mining company reports.

With a capacity to transport 240 t, the trucks are controlled by computer systems, GPS, radar and artificial intelligence, covering the route between the mining front and the unloading area. The result of six years of research and testing, autonomous vehicles began to be used in 2016 in test mode. In 2019, all 13 trucks circulating in Brucutu were already using the new technology, making it the first mine in Brazil with 100% autonomous operation. 

Vale states that the fuel consumption of autonomous trucks is 11% lower than that of crewed trucks, resulting in a reduction of 4 300 t/y of carbon dioxide.  

The maximum speed of the trucks, which was 40 km/h, reached 60 km/h. Hourly productivity, measured by the amount of iron-ore transported per hour, increased by 11% - five percentage points more than expected. 

The autonomous operation also favours the maintenance of equipment. Tyres, for example, had a 35% increase in their useful life – ten percentage points more than expected. In addition to saving the company, this number generates less waste disposal. 

Operators who used to stay in the cabin received training and were relocated to other functions, one of them being the operation in the control rooms – with air conditioning, without vibration and noise – kilometers away from the mining front. With this, risk situations involving truck operators, such as tipping and collision, were eliminated. 

“There are many results and lessons learned to be celebrated with the current level of maturity of the autonomous mine,” explains the executive manager of the Brucutu and Água Limpa complex, Jefferson Corraide.

“Certainly, the most important advance provided by the implementation is the reduction of people's exposure to risk. The mine was made safer both by the embedded technology and by the discipline required to make the process sustainable and fluid. The autonomous operation optimisation processes go beyond the truck and encompass the complex as a whole.”

Brucutu operation and infrastructure manager Kléber Gonçalves explains that within the mining area, manned and autonomous vehicles are in constant interaction and, in order for it to be safe, all vehicles are adapted. This allows autonomous trucks to plot their routes and, preventively, reduce speed or even interrupt their route, avoiding accidents.

"The equipment also has sensors that continuously map and identify the terrain, objects and people, so that the autonomous technology can paralyse the operation of one or more trucks in case of changes that were not foreseen in the path determined by the centre control," he says.

Vale's self-employed programme continues to expand. Currently, tests are being carried out with autonomous trucks in Carajás. Vale also invests in autonomous drills. There are 11 of them in operation in Minas Gerais and Pará. Another ongoing project is to automate yard machines, which has already been completed in Malaysia and is being implemented in four Brazilian states.