Tag Archives: Minerals Council South Africa

UP’s Vehicle Dynamics Group to boost UG mine safety with new testing facility

An engineering team at the University of Pretoria (UP) has pioneered an underground procedure which tests the performance of collision avoidance systems (CAS) in an effort to improve the safety of workers on mines through reducing unwanted interaction between vehicles and pedestrians.

The Vehicle Dynamics Group (VDG) is a research unit at UP’s Department of Mechanical and Aeronautical Engineering that is actively involved in the South Africa and international mining industry.

It saw a need to develop such a system based on the continued number of fatalities that have occurred as a result of interaction with mining machines and to be in step with subsequent changes (yet to be promulgated) in Chapter 8 of South Africa’s Mine Health and Safety Act (1996) that requires trackless mobile machines to warn the operator if a significant risk of collision exists. If the operator fails to heed the warning, the machine must automatically slow down and stop safely.

“Mining machines are becoming smarter by the day, with smart, connected vehicles promising to be the mining method of the future,” Professor Schalk Els, VDG Researcher, said. “Smart mining machines are now utilising technology such as high-precision GPS and automotive radars to prevent unwanted interaction with other machines, pedestrians and infrastructure.”

Dr Herman Hamersma, also a VDG Researcher, added: “This development is a stepping stone to full autonomy – not only on mines but in urban and highway environments too. Mining machines typically perform repetitive tasks with well-defined mission profiles, which allows for the automation of many of their operations.”

The VDG has aided in the formulation of industry guidelines to analyse and improve the readiness level of collision avoidance offerings on the market, according to UP, and has developed a standard testing procedure to evaluate both surface and underground collision management systems based on guidelines set out by the Minerals Council South Africa.

CAS assessments were previously limited to above-ground testing, with UP saying its involvement has brought about change in the CAS space, having contributed significantly to the increasing maturity of commercial offerings.

“With the VDG’s recent development of an underground testing system, it is anticipated that the technology readiness of current underground CAS offerings will be even more improved,” it said.

The performance of CAS is tested by way of a stage-gate approach. The first stage gate is a lab-scale test conducted on light vehicles in a controlled environment. The CAS is installed on the light vehicles exactly as would be in a mining environment.

Dr Hamersma said: “These vehicles are equipped with brake robots that control the stopping distance and can be controlled to represent minimum brake specifications, while high-precision GPS accurately measures the speeds and positions of the vehicles. An advanced data capturing and control system is used to control the brake robot and to record the GPS data, and the decisions communicated to the test vehicle by the CAS.”

If the CAS passes the lab-scale test, it can proceed to the next stage-gate, where the system is subjected to a single interaction test conducted in an environment that is more representative of a mine. To date, testing has been limited to surface tests due to the reliance on high-precision GPS as the ground truth measurement. However, the VDG team’s recent development of an underground system makes use of LiDAR (which uses laser light to calculate distances), cameras and automotive radar to measure the distance between objects and their speeds.

The system has been tested at a training facility at one of South Africa’s underground mines, and the first live underground single interaction test is in the pipeline. The system will be used to validate the lab-scale results of underground CAS solutions in their intended underground environment where line of sight, dust and uneven, slippery road surfaces are serious concerns.

The international community has noticed the activity in this space in South Africa, and this has led to collaborations with international CAS vendors and industry bodies such as the International Council on Mining & Metals (ICMM), the ISO working group leading the development of the collision avoidance standard and a project in collaboration with Mining3, a research institute based in Australia that was funded by the Australian Coal Association Research Programme (ACARP).

SRK reflects on rock-related accidents in South Africa mining industry

Rock-related accidents in South Africa’s mining sector have reduced significantly in recent decades, due in large part to incremental improvements in rock engineering practice, SRK Consulting explains.

According to William Joughin (pictured), Chairman of SRK Consulting and himself a rock engineering expert, the company’s contribution in this field has included assisting mines with reviews of safety practices, as well as providing safe rock engineering designs and detailed seismic hazard analysis.

Fall of ground (FOG) is the leading cause of fatalities in the sector, making up a third of mining fatalities in 2019, according to the Minerals Council South Africa. The organisation has reported recently that total FOG injuries have dropped from 1,121 in 2003 to 379 in 2019, while FOG fatalities are down from 131 to 20 over this period.

Joughin notes, however, that this reduction in the number of injuries and fatalities is also linked to the general decline in mining industry employment. There have been few major technological changes implemented in the last five years, in particular, which could help reduce injuries and fatalities. Instead, the focus has been on behavioural change.

“The industry is focusing its efforts on changing human behaviour, because the exposure of people remains high and workers have to manually implement safety measures,” Joughin said. “These efforts have had mixed results, but there is renewed research and development into mechanisation that could significantly reduce the exposure of workers to the more hazardous aspects of mining.”

Methods of seismic monitoring and hazard analysis continue to be developed as new technologies become available. Within its diverse range of projects conducted for the mining industry, SRK contributes to raising safety levels in South Africa mines in these and other ways, according to SRK Consulting Director and Principal Consultant, Andrew van Zyl.

“We have been involved in the Test Mine project and are currently involved with Mine Health and Safety Council projects on collision control and rock safety,” Van Zyl said. “We are also doing pioneering geotechnical work in both the open pit and underground environment.”

He added that the company’s work on water management and mine closure also contribute indirectly to the general levels of improved safety in mining, as do its contributions to tailings dam management in and around mines.