IM 2020 April 20 | Page 71

FLEET AUTOMATION autonomous system that was discussed thoroughly in the risk assessments was that when the truck was in manual mode, the autonomous system components had no effect on the original equipment manufacturer (OEM) design. Similarly, the system was designed so that when in autonomous mode any manual input to the OEM brake or steering system would cause the autonomous system to release control of the vehicle. Once the autonomous kit was installed on the first haul truck testing and tuning of the components began. From the initial risk assessments, it was determined that a test track isolated from other operations would be required. The test track was constructed to allow the simulation of a mining environment including shovel load areas with cable trees, dump edges, stack dumps, roads, ramps, and a large open area to allow for various control tuning operations.” An NGM supervisor was used as the testing coordinator, this supervisor was responsible for controlling access to the test track. While testing was taking place, a roadblock was used at the entrance to the track. The personnel maintaining the roadblock only allowed vehicles past that had made positive communication with the supervisor at the test track after the supervisor had ensured the autonomous vehicle was locked out. At the start of each day of testing at the test track, ASI, Sedna, and NGM employees met and completed a daily test plan and team risk assessment. The team risk assessment was the controlling document for the tests to take place that day. The testing supervisor was responsible for ensuring that all personnel that entered the test track were aware of the tests and potential hazards that would be taking place. At the end of each day ASI would report the test results to the project team. “The main risk mitigation during testing was the use of a ‘safety rider.’ The safety rider sat in the operator’s seat of the truck while an ASI engineer sat in the passenger seat. If at any time the truck began to do any unsafe action, the safety rider would override the autonomous system and bring the truck to a safe stop. Specialised training took place for Safety Riders so that they could see how the equipment would respond. To evaluate the risk associated with the design of the ASI system hardware and software a thorough review of the system was performed using the system theoretical process analysis (STPA) process.” The STPA process was extensive and resulted in several changes to the system design and new trainings to be developed. “The switch to automated haulage required many new standard operating procedures (SOP) to be developed to ensure worker safety and to realise efficiency gains. There were also many existing procedures that required modification for use in an autonomous setting. Procedures needing to be written and those needing revision were identified during the risk assessment process. A small group of NGM project team members, ASI, and Sedna representatives developed a detailed flow diagram for each procedure. At this point the employees selected as control room operators, maintenance technicians, and shift supervisors were given the flow diagrams and given the task of creating written procedures for each of the flow diagrams. NGM, ASI, and Sedna employees involved in creating the flow diagrams were available to the operators throughout the process of creating the written procedures to answer any questions or concerns that the operators may have had. In all 21 new procedures were developed and five existing procedures were highly modified.” A key component of operator training was the use of simulators to familiarise the operators with the use of the Mobius control software. A preliminary map of the mining area was created and uploaded into Mobius, operators were then rotated between monitoring trucks, managing maps, and running the simulated shovel interface. The simulator training was crucial in the operators learning how path planning occurred, how close to map edges and obstacles the trucks would get, and best practices for the placement of cable trees. The simulator training also allowed planning and user interface issues to identified early in the project. IM ABSOLUTE MATERIAL FLOW CONTROL CHUTE SYSTEMS & SOLUTIONS t0QUJNVNNBUFSJBMnPX t6QUPEFDSFBTFJONBUFSJBMEFHSBEBUJPO t3FEVDFEEVTUBOEOPJTFMFWFMT t7JSUVBMMZNBJOUFOBODFGSFF t(SFBUMZSFEVDFETQJMMBHF t4JHOJmDBOUSFEVDUJPOJOCFMUEBNBHF Tel: +27 (0) 11 827-9372 email: info@webachutes.com www.webachutes.com APRIL 2020 | International Mining 67