Subproject E01

Optical 3D-bridge-inspect: Innovative inspection of complex infrastructure combining very high-resolution UAV-borne imagery and structured-light scanning

Currently the necessary bridge inspections are mostly done manually by highly qualified operators who have yearlong experience on detecting possible dangerous damages on the bridges like cracks. But these manual inspections, even if are considered reliable, are still a subjective method and usually time consuming, as well as dangerous for the operators.

In this sub-project of the SPP, we will combine several state-of-the-art sensor technologies and emerging approaches to data processing and machine learning: Unmanned aerial vehicles (UAVs) - or drones - will be equipped with high-quality cameras and used to access hard-to-reach areas of the bridge and to capture high-resolution images that will be processed by a computer vision module for automatic analysis; making them a powerful and flexible tool for structural health monitoring. We will use high-resolution full-frame metric cameras in combination with appropriate multirotor carriers to monitor comprehensive geometric deformation of the entire construction and visual damage at the structure. In addition, we will makes use of structured light scanner that can resolve a surface which are able to resolve a surface in three dimensions in the sub-mm range. All sensors will be registered together in a coordinate system defined by the infrastructure and that is stable in time. By using an innovative approach to control the UAV and combining all sensor data in an advanced deep-learning image interpretation approach, we propose a holistic vison-based monitoring method.

The work programme for the three years consists of four work packages (WP):

WP 1: Geometric bridge monitoring based on UAV observations

WP 2: Recording of neuralgic areas by UAV

WP 3: High-precision detection of neuralgic areas with structured light scanner

WP 4: Detection of cracks and spalling

The methods to be developed will be applicable not only to bridge structures but also to the monitoring of other complex infrastructure structures, as they are generic in principle.