Understanding Fill Factor vs. Fuel Efficiency for Excavator Operation: A Case Study of Bench Loading

The fill factor is a key metric used to evaluate the performance and efficiency of the excavator's autonomous functions and operations. Optimizing the fill factor allows for an objective definition of a "poor bucket" and provides an opportunity for reducing the emissions from operating heavy equipment. This article aims to study the effect of fill factor (%) on fuel efficiency for a bench-loading exercise. Two cases were developed "Bucket Normal" where excavation is completed at a pre-selected fill factor, and "Bucket Return" where initial excavation is returned to achieve 100% fill factor. The task efficiency of different fill factors was reported, and the statistical analysis shows there is no difference in fuel efficiency at 70% fill factor and above. This indicates an optimal fill factor where it is no longer energy efficient for an automated excavator to return the poorly excavated load. The optimal fill factor and relationship with fuel efficiency can be incorporated into existing algorithms for teleoperated and automated excavators to improve the productivity and energy efficiency of soil excavation.