Mechanical Technology March 2015

⎪ Modern transport and vehicle solutions ⎪

Pedestrian detection systems for surface mining

With the Department of Mineral Resources (DMR) unveiling its draft of the mandatory Code of Practice for Trackless Mobile Machinery (TMM), detection systems’ pioneer, Booyco Electronics is unveiling its very low frequency pedestrian detection system for surface mining machinery. Anton Lourens, the company’s MD reveals more.

B ooyco Electronics, which has been at the forefront of Pedes- trian Detection Systems (PDS) in the South African mining industry since 2006, is pioneering the technology for surface-mining applica- tions after successfully launching it for underground operations. “We have found that our very low frequency (VLF) tech- nology, which has proved so successful underground, is exceptionally flexible in terms of surface mining operations,” says managing director, Anton Lourens. Whereas underground mining equip- ment is generally standardised due to space constraints, surface mines feature a much broader range of equipment, from smaller machines to ultra-class dump trucks, for example. “Bigger machines mean bigger exclusion zones, which meant we had to adapt our technology to suit the specific requirements of surface operations,” Lourens says. Booyco Electronics also had to take into account the potential interference from ancillary equipment. “Although our PDS technology complies with EMI and EMC (electromagnetic interference and connectivity) requirements, we had to contend with additional issues such as GPS positioning and vehicle tracker systems, for example. Managing all of

that posed a challenge that we have successfully overcome.” Lourens reveals that Booyco Elec­ tronics is currently installing its PDS technology at a surface mining operation. “We have completed the mining opera- tion side and are currently busy with the mineral processing side, wherein lie more challenges and definitely a lot more applications. We have standardised the PDS deployment, i.e. specific zone shaping per vehicle type, which took time analysing the operational requirements.” What this meant was that whereas Booyco Electronics would typically rec- ommend a 10 m wide warning zone, for example, the client would request that this zone be made smaller. “One of the definite advantages of our technology is that it is inherently flexible, enabling us to adapt it according to specific re- quirements and vehicle type,” Lourens explains. While the main function of PDS technology is to warn miners of any ap- proaching vehicles, it includes two-way communications to warn the operators of any mobile equipment if there are any miners in the vicinity. The PDS is based on VLF as well as radio frequency (RF) technology, with miners equipped with two-way RFID tags. Vehicle or other

Anton Lourens (left), managing director of Booyco Electronics. static danger zones have VLF antennae, which generate several stable and pre- determined fields in front of and behind the vehicle in question, altough the con- figuration will differ for surface mining operations. When a miner enters this zone, his tag is activated and a warning signal is triggered. The exclusion zones can be up to 15 m long. Looking more closely at the hardware, Lourens explains that the unit transmits a VLF signal of less than 15 kHz via ferrite antennae, which creates exclusion zones in both directions of travel. When a driver himself needs to be warned, the control unit then receives a UHF signal from the miner’s tag, which in turn activates the relevant alarm. The power requirement for the unit is 12 V dc. The antenna is mounted in a resin- filled, plastic enclosure. On machinery

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Mechanical Technology — March 2015