Abstract: A propeller system with two propellers, arranged one behind the other and separated by a propeller gap, respectively comprising a propeller hub and at least one rotating force measuring device, comprises at least two differential pressure sensors and an evaluation unit. The rotating force measuring devices are mechanically connected to the respective propellers and are adapted for determining the individual thrust force of each propeller. At least one of the said differential pressure sensors is arranged on or in each propeller and is adapted for measuring a differential pressure between the propeller gap and the respectively opposing side of the propeller. By adding the measured individual thrust forces and by subtracting the gap area forces that are based on the respectively measured differential pressures, the evaluation unit can determine a precise overall thrust force for the propeller system.

Abstract: A force measuring system is provided for measuring forces on a rotating body that includes, but is not limited to a force measuring device, which is mounted on the rotating body, as well as a position sensing unit for detecting the rotation of the rotating body and an evaluation unit, which is connected to the force measuring device and the position sensing unit. The evaluation unit is configured for recording a force value measured by the force measuring device depending on the detected position of the rotating body. The force measuring system allows the forces and torques on a rotating body to be determined precisely and as flexibly as possible, independently of the prevailing rotation speed of the rotating body.

Abstract: A propeller system with two propellers, arranged one behind the other and separated by a propeller gap, respectively comprising a propeller hub and at least one rotating force measuring device, comprises at least two differential pressure sensors and an evaluation unit. The rotating force measuring devices are mechanically connected to the respective propellers and are adapted for determining the individual thrust force of each propeller. At least one of the said differential pressure sensors is arranged on or in each propeller and is adapted for measuring a differential pressure between the propeller gap and the respectively opposing side of the propeller. By adding the measured individual thrust forces and by subtracting the gap area forces that are based on the respectively measured differential pressures, the evaluation unit can determine a precise overall thrust force for the propeller system.

Abstract: A force measuring system is provided for measuring forces on a rotating body that includes, but is not limited to a force measuring device, which is mounted on the rotating body, as well as a position sensing unit for detecting the rotation of the rotating body and an evaluation unit, which is connected to the force measuring device and the position sensing unit. The evaluation unit is configured for recording a force value measured by the force measuring device depending on the detected position of the rotating body. The force measuring system allows the forces and torques on a rotating body to be determined precisely and as flexibly as possible, independently of the prevailing rotation speed of the rotating body.