New Tests on Autonomous Forest Machine Yield Promising Results

Researchers at Luleå University of Technology have recently conducted a series of remarkable tests on an autonomous forwarder, in collaboration with the University of Oulu. The tests, conducted as part of the InterReg Aurora project "Sustainable Autonomous Material Handling (SAMHand)," aimed to evaluate and enhance the forwarder's autonomous functionality.

In the tests conducted, researchers in the field of machine design evaluated an autonomously operating forwarder using a new method where the machine was secured with dynamometers. The goal of this method was to simulate realistic load scenarios through a digital twin, providing a more accurate picture of the machine's performance and possible improvements.

Opened a Range of New Insights

"We wanted to recreate the working conditions the machine is exposed to in reality, but under controlled conditions. By connecting the machine's hub motors to the dynamometers, we were able to transfer the load from the digital twin directly to the forwarder," explains Magnus Karlberg, Professor of Machine Design at Luleå University of Technology.

The purpose of the tests was to precisely measure and analyze the machine's behavior under different load conditions. The dynamometers made it possible to monitor parameters such as torque, hydraulic system pressure, and wheel speeds, while also recording steering angles and GPS positions. This meticulous measurement method has opened up a range of new insights.

"Our strategy has been to start with more basic load cases and low loads, then gradually increase them. A challenge has been to calibrate the different control systems and communications so that the system does not enter into self-oscillation," says Magnus Karlberg.

The results of the tests are promising and have already begun to influence the continued development of the forwarder. Besides evaluating the hybrid test methodology itself, it now also enables standardized tests in controlled environments, which in turn streamlines the development of autonomous algorithms.

"We see great potential in using these results to train detectors and improve the machine's autonomous functions in different environments. The next step is to enhance the automation of the forwarding function and begin working on autonomous navigation in rough terrain."

Driving Development Forward

The collaboration with the University of Oulu has been a central part of the project. Within the InterReg Aurora project "Sustainable Autonomous Material Handling (SAMHand)," research groups are working together to further develop this hybrid test methodology and improve the machine's ability to handle materials autonomously.

"Together, we hope to drive development forward and contribute to a sustainable future for autonomous forest machines," concludes Magnus Karlberg.

• Machine Design