The new Cat Autonomous Water Truck conserves water and cuts costs on mining sites

The new Cat 789D Autonomous Water Truck (AWT) allows mine operations to digitally track water consumption and reduce waste, designed with the goal of eliminating road overwatering and underwatering. Fully integrating into the mine site's Cat Command autonomous haulage fleet to control haul road dust, the market's first commercially available AWT is built on the 789D mining truck chassis and integrates the truck, tank, and Cat Water Delivery System (WDS), connected with Cat MineStar technology.

In an effort to maximize efficiency, the fully autonomous truck reduces shift changes, meal breaks, and other operational delays. Complying with watering plans, the water truck interacts with other autonomous equipment and integrates with contractor mining processes and systems managed by MineStar. 

The 789D is the largest Cat water truck product offering that can accommodate up to 165,000 litres (43,588 gallons), depending on tank configuration. The AWT senses when the water tank is running low and can be programmed to integrate with the water refill station to automate the water refill process. The auto-shutoff feature prevents tank overfilling. 

The Cat 789D AWT is fully integrated with Cat MineStar

The team intentionally planned the integration of the Cat MineStar Command for hauling and the Cat WDS. Cat shares that it aimed to build communication between the truck on-board systems and the office control console to work alongside the Cat WDS interface. 

To ensure proper communication between the water delivery system and MineStar, a compatibility check has been implemented in Cat WDS to confirm all truck control systems are running compatible software and reporting any onboard failures to the MineStar system for appropriate corrective action. 

Integrated into the truck's design is the exclusive Cat WDS that varies water flow based on truck speed and automatically determines the correct amount of water needed to control dust. Knowing where, when, and how much water to dispense, the 789D AWT helps contractors conserve water, a scarce resource at many mining locations around the world.

When truck speed drops below the minimum watering speed setting, determined by site operations, the system halts water delivery to help prevent overwatering, poor traction, and damage to haul road intersections and other stopping areas. When truck speed exceeds the minimum watering speed setting, the system begins depositing the specified amount of water set by MineStar. Cat WDS actively monitors the water level and automatically turns off watering once the tank is empty. To reduce potential damage, the system has multiple safeguards in place to prevent the water pump from running dry. 

The automated system's flat, controlled spray pattern delivers maximized litres-per-square-meter (gallons-per-square-foot) coverage across the haul road. Larger, heavier droplets designed to reach the ground help to reduce spray loss to wind and evaporation.

Reducing health hazards associated with airborne particles, automated water delivery supports the reduction of dust that limits operator visibility for staffed equipment to enhance overall site safety. Remote tank fill control, complete with auto shut-off to prevent overfilling, eliminates the need for a worker to be involved in the refilling process, reducing the potential of slips and falls.

Mines can quickly switch the flexible 789D AWT from autonomous mode to staffed mode as necessary for tasks like front water cannon operation. The cannon has a capacity of distributing up to 2,839 litres/min (759 gallons/min) with a spray distance reaching 60 metres (200 feet). Even with the staffed operation, Auto Mode water delivery automates the watering process to leverage variable water flow and automatic determination of the correct amount of water needed to control dust.

Packages available on the Cat 789D AWT

The basic package allows sites to track their asset and see when, where, and how it is performing:

• Location of truck
• Water level
• Fuel level
• Watering mode
• Truck speed
• Truck refills
• Water dispersed
• Truck utilization per shift

The premium package will allow sites to track how their water trucks are tending to the site's watering needs:

• Overall watering heat map to show the age of water currently put down by all trucks in a shift
• Watering heat map by truck to show where each truck watered and what mode was utilized
• Utilization of fill spots by each truck
• Replay of truck watering activity for up to 8 previous weeks of data, depending on how many assets are tracked
• Suggested area to water based on age of water and traffic utilization

When the site is ready for full autonomous mode, the water truck can be integrated into the MineStar ecosystem to work alongside the rest of the mining fleet.

"To meet contractor requirements for dust control, Caterpillar implemented a MineStar-integrated watering model based on many years of site watering studies and Cat WDS performance data," explains Corey Wurtzbacher, general manager and vice president of technology and global sales support at Caterpillar.

He continued: "This model allows the truck to monitor traffic, weather, and road conditions, prioritize what areas need to be watered, when the areas need to be watered, and how many passes it should take to apply the correct amount of water saturation, for the given conditions. The integration of Caterpillar's many years of autonomous truck operations and water delivery development have been combined to make a high-performing autonomous watering solution."