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The two test devices have been built to help study the frictional, wear, and thermal behaviors of marine thruster lip seals.  Due to their relatively large size (designed to run on shafts 300 mm), these seals are seldom studied in the literature. The test devices offer a robust means to investigate the behavior of marine thruster lip seals, particularly their difficult to estimate thermal behavior.

Movement of piston rings in relation to piston in an internal combustion engine affects the transport of lubricating oil into the combustion chamber. Lubricating oil interferes with the combustion event and causes issues when using greener fuels such as hydrogen. Piston ring dynamics are investigated in a static laboratory scale testbench that provides a more controlled environment for developing measurement methods for piston ring position.

Vibrations can be harmful for critical components in rotating machinery. Wire rope isolators can be used to keep vibrations at acceptable levels. They have good damping properties due to frictional losses between wires, and their nonlinear stiffness properties are beneficial in isolation applications. This research aims to better understand how the beahvior of wire rope isolators is affected when they have been in use for a long time. Possible changes in, for example, effective stiffness are critical to be aware of when designing wire rope isolators for industrial applications. So far wire rope isolators have shown excellent capability of attenuation attenuating lateral vibrations. Yet, they have not been investigated thoroughly in torsional applications. Therefore, this research also aims to explore whether wire ropes could be used to effectively attenuate torsional vibrations.

Eddy current sensors measure relative distance to the shaft, determining shaft movement. However, the measurement is affected by electrical runout. Electrical runout is a measurement error in eddy current sensors, caused by variations in the material properties of the target. Electrical runout is a significant error cause when measurements are taken with micrometer accuracy. The research focuses on how this electrical runout could be reduced with diamond burnishing.

Air bearings are gas lubricated bearings, which enable high-speed precision motion with low friction. Air bearings have interesting new applications in production machinery, where increasing demands on quality and energy consumption make traditional solutions infeasible. The research at ARotor has improved the understanding of the manufacturing process and performance of air bearings. Current research topics include the use of porous graphite aerostatic bearings as a sensor and manufacturing of gas bearings with metal 3D printing.

The quality of paper can be analyzed by measuring paper samples in the laboratory or on the paper machine during production. In our laboratory, we use a paper analyzer that allows us to measure the thickness of paper from samples that are kilometers long. Thanks to the measuring device, we obtain data for analysis that allows us to assess the performance of the paper machine. Therefore, paper quality reveals important information about the machine's operation, such as the condition of the rolls, vibration, or adjustment issues.

AI can be used to monitor rotating machinery for both diagnosis (current condition) and prognosis (failure prediction) based on sensor data. Training such models requires data from both healthy and faulty conditions. This is generated using a test bench—a scaled maritime thruster—where realistic loads are applied via a load motor, from steady operation to simulated ice impacts. The dataset includes multiple gear faults and is collected using sensors such as accelerometers, torque transducers, and encoders.

The aim of virtual sensing in maritime propulsion systems is to estimate quantities, such as torque and rotational speed, which are conventionally measured using physical sensors. Virtual sensors provide information from locations on the drivetrain that are inaccessible with physical sensors.