Mining giant Glencore Ferroalloy’s development and implementation of a “people vehicle detection stop” system (PVDS) to avoid collision and prevent injuries and the possible loss of life has proven to be a success.

However, the technology alone is not a silver bullet, but rather a part of an ecosystem comprising behaviour change, collaboration and partnership, thoughtful processes, the application of lessons learnt and adaptation, besides others, says Glencore Ferroalloys South Africa group engineering manager Roy Murley.

In the first quarter of this year, Murley was awarded a gold medal by the Association of Mine Managers in South Africa for a technical paper, ‘Trackless Mobile Machine Collision Avoidance System at Glencore Waterval Mine’, based on the years-long project, which was developed in 2015 and deployed from 2016.

In a journey that spans a decade, the project stemmed from two trackless mobile machine critical incidents experienced at Glencore’s Ferroalloy Mines and ultimately resulted in the companywide deployment, in stages, of the PVDS technology from 2016 to 2019.

A collision avoidance system was previously installed at various Glencore Alloys mining operations and provided effective proximity detection and warning to machine operators and employees; however, the systems were not designed for the intervention and control of the actual mining vehicle movement and relied on the operator to react to the warnings and alarms generated by the system for final collision avoidance.

The older system used a single technology radio frequency but lacked time-of-flight technology, which accurately determines the distance and the position of a person to a machine in its surroundings, he explains.

Through the continued support and mandate from Glencore’s Ferroalloys management team, Murley led the team that presented collision detection service providers with the challenge of developing and implementing a collision avoidance PVDS that could be incorporated into legacy machinery without the need for continuous upgrades.

“We partnered with different collision detection suppliers and worked with them to develop the innovative PVDS, which is the first of its kind fitted to diesel vehicles,” he adds, noting that the companies were put to the test on different mines within Alloys, with a proof-of-concept drafted and tested in parallel.

“One of the main objectives was that the system needed to actively intervene with the operation of the machine, thereby reducing the system’s dependency on the responsiveness of the vehicle operator to warnings and alarms,” he says.

The system uses an electronic tag attached to every worker’s headlamp cord, proximity sensing equipment and a collision avoidance interface fitted in the vehicles, with the PVDS warning individuals of nearby vehicles with a flashing light and audible alarm on the lamp tag, while the driver of the vehicle is alerted to the nearby worker by accurately displaying the worker or vehicle screen in the cab in their vehicles.

“This progressive technology stops the vehicle entirely once it comes within five metres of a person,” he adds, noting that warnings were issued at 10 m and detection can be up to 30 m depending on the vehicle’s speed.

The tags attached to the workers also indicate whether the employee is permitted to work in close proximity of, or interact with, the vehicle, at what time the interactions took place and how many instances.

The innovative technology sets a benchmark for safe work practice at Glencore’s Ferroalloys mines and the industry at large, as the system enables significant data collection for improved safety and increased production, Murley comments, noting the ability to detect and track “hotspots” in real time.

This includes areas where the mine’s traffic management plan does not work effectively and where people and machines still interact unnecessarily, enabling the company to continuously find solutions for any problematic areas, either by building cross over bridges where required, separating traveling ways further or establishing dedicated traveling areas in a workshop, for example.

Further, the system can track a person in the case of an emergency, recording the last known presence and enabling the finding of a lost worker or rescue if required, the head lamp cord is equipped with a feature wherein turning the tag 180 degrees will send out a distress signal “Global Stop” if a worker is in a difficult situation and requires help.

In this case, all equipment within the employee’s immediate vicinity will retard and stop.

In terms of production efficiencies, the data produced from the system also enables, with modifications, the company to measure the amount of loads and tonnes undertaken by a specific machine.

“When we installed the collision avoidance, we actually made the machines more intelligent,” Murley points out.

However, technology is only one part of the solution, with the human element also needing focus.

“When deploying technology, there is a need to change the environment around it,” he tells Mining Weekly.

“In the past, you would think that your traffic management plans are entrenched, with specific machine only zones, pedestrian only zones and a combination thereof, with assumptions that people are following the rules.

However, an analysis of data shows that people often breach the rules.

“When we rolled out the system, in the first week we recorded 24 000 interactions in the critical zone.”

“We used that data positively and we managed to turn this around within two weeks to 12 000 interactions. Those 12 000 interactions were reduced even further to about 1 400 to 1 500, and those interactions are interactions where it is an employee that is required or has permission to get close to the machine.”

Once the technology is established, it becomes a “human thing”, he notes.

“This technology alone is not a silver bullet.”

Each case, each mine, each machine and the culture difference on different mines requires a customised response, with complacency trends, previous learnings, culture and behavioural trends taken into account.

Upskilling for the operation and maintenance of the new technology is also required, as well as complacency monitoring following technological adoption as people become more trusting of the technology. MW