Automated Pile Transfer Work Cycles with a Robotic Wheel Loader

This paper presents two autonomous pile transfer experiments with a robotic compact wheel loader. The main objectives were to achieve automated load-haul-dump work cycles which successfully transported material, and also... [ view full abstract ]

This paper presents two autonomous pile transfer experiments with a robotic compact wheel loader. The main objectives were to achieve automated load-haul-dump work cycles which successfully transported material, and also updated the scooping and dumping location if needed based on the high-level plan and changing worksite topography. This would then demonstrate the potential for the system to work autonomously until job completion. A high-level plan consisting of a scooping and dumping area is first specified using a 3D graphical user interface. This consists of interactive graphical tools rendered on a surface model of the site, which is obtained using an on-board laser scanner. Commands for loading, hauling and dumping actions are then generated and followed autonomously without any further human input. The experiments include a 5-cycle test over 9 minutes, though with 2 unsuccessful scooping actions, and a 10-cycle test over 24 minutes, with one unsuccessful scooping action. During these tests, new ground models were made during each cycle to assess the current topography, which resulted in updated scooping and dumping locations. Several areas for improvement were identified, such as implementing a more effective loading strategy and more efficient path planning. Overall the system shows potential for enabling even longer-duration autonomous operations, and to be used for comparing different planning and control strategies.