Massive surface mining machines working close to each other and near stationary objects are at risk of collisions. Caterpillar developed its comprehensive safety system, Detect, based on a simple premise: The more that equipment operators and mine administrators know about the working environment surrounding mobile equipment, the more safely all at the site can perform their jobs. Proximity Awareness brings the right information at the right time to the right people.
Detect, a capability set within Cat MineStar System, allows mines to equip machines with practical, site specific systems that can both enhance operator awareness of the working environment and provide mine administrators with effective mobile equipment control in the interest of safety. In surface mining applications, Detect offers three levels of operator and administrator awareness: Vision, Object Detection and Proximity Awareness.
Vision provides multiple cameras that allow operators to select the views, via an in-cab display, required to best assess objects and activity around their machines. Object Detection adds multiple radar sensors to the Vision capability, allowing the combined systems to identify hazards within critical zones around the machine and to display the hazard along with a graphic "proximity bar" that provides perspective for the operator.
Proximity Awareness builds on the capabilities of Vision and Object Detection by equipping all appropriate machines at the site with Global Navigation Satellite System (GNSS) receivers and data radios that continually report their positions to a central office and to each other, which then broadcasts this information to all assets equipped with the system. The net result is that every machine operator is aware of the real-time position of all other reporting assets.
The power of Proximity Awareness, however, extends beyond this capability. By creating a digital envelope that defines a machine's physical dimensions (body), and by creating avoidance areas within and around the envelope, the system can determine the possibility of these envelopes intersecting using "path projection" technology. If a collision is anticipated, the system can provide adequate warning to operators.
Although the technology involves complex computations, the Proximity Awareness system presents this data to the operator via an intuitive graphic display in the cab. The system provides a low priority alarm when the path projection regions of two machines intersect, advising the operator with a graphic display on the site map, along with audio and visual alerts. A high priority alarm occurs when the avoidance areas and the body areas of two machines intersect, but with enough advance warning to enable operators to take corrective actions. Critical priority alarming occurs when body areas of two machines intersect, indicating immediate action is necessary. If machines routinely are in close proximity, such as loading and hauling vehicles, alarm filters can be implemented between machines classes to silence non-critical warnings.
Other features of Proximity Awareness include the ability for mining truck drivers to identify and report hazards, such as a boulder on the haul road. The administrator can evaluate the hazard, or the system can be configured to automatically distribute this updated information to all mobile assets in the system.
Proximity Awareness also provides continual information to the administrator about machine speeds, avoidance zones, and known hazards, allowing real-time feedback for effective control of the overall site. The system also allows capturing and playing back selected events by using the playback bar at the bottom of the incident map, which enables the administrator to determine the exact location of machines during the time surrounding the event.