Fibre-optic tactile probe to determine relative motion between a drone and a measurement object for motion correction of a short-range 3D inspection lidar

• Applicant: Professor Dr. Thomas Kissinger
• Subject Area: Measurement Systems
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 541029557

Drone-based object monitoring, e.g. of bridges, wind turbines or aircraft, has experienced rapid development in recent decades. One widespread application are imaging techniques for inspecting damage. Quantitative measurements, e.g. the determination of damage depth, are much more demanding than purely qualitative observations, but are becoming increasingly important, for example to make clear decisions on compliance with maximum permissible values. Quantitative, drone-based measurements in open-air environments are complicated in particular by frequently occurring environmental disturbances, for example wind movements or target vibrations. The proposed project seeks to contribute to this problem area by investigating a novel solution to the problem of the direct measurement of relative position and orientation changes between an object to be inspected, e.g. a wind turbine blade, and a measurement drone flying in the vicinity of the object. This will be possible using a fiber-optic tactile sensor, which remains in contact with the target via a rubber foot throughout the measurement period and directly measures the relative movement between the target and the drone using a fiber-optic shape sensing approach. In contrast to alternative methods, e.g. based on drone-integrated inertial sensors, the motion/vibration of the target can be included in the motion correction and measurement uncertainties due to integration drift can be avoided. The information gained from this can be used to correct for disturbing movements and the measurement data can then be registered directly in the coordinate system of the measurement object. In the proposed project, this technology will be used in an exemplary application for 3D image stabilization of a short-range inspection lidar, and the resulting improvement in measurement quality will be analysed in detail and quantified by setting up a metrological uncertainty model.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2433: Metrology on flying platforms