Concept of an autonomous mobile robotic system for bridge inspection

Abstract

In the next decade, many old bridges will be exposed to increasing traffic loads and destructive environmental conditions. Measurement methods like laser scanning, infrared thermography, photogrammetry, ground penetrating radar, or ultrasonic scanning are used on single robotic systems to partially support the inspectors. However, time-consuming manual inspections for crack detection, measurement, and documentation are still necessary. This paper describes the concept of an autonomous mobile robotic bridge inspection system. The proposed concept for an unmanned ground vehicle (UGV) is achieved by a trade-off of different mobile platforms, sensor systems for mapping, localization and inspection, and first tests assessing the feasibility. We use a small concrete bridge in Freiburg (Germany) with various cracks for testing the sensors, the UGV concept, and initial tests of the mobile platform. This results in the choice of selecting the weatherproof version of the mobile robotic platform Husky from Clearpath Robotics. It is equipped with Swift Navigation's Duro real-time kinematic (RTK) system, a heading system, an inertial measurement unit (IMU), a base station, and software for semi-autonomous navigation. In the next step, we compare different sensor systems. For mapping and localization, we decide to use the 360 • spherical camera Ladybug 5+ from FLIR Systems and a Velodyne VLP-16 light detection and ranging (LiDAR). High-resolution cameras allow recording damages on the bridge's surface. We perform first tests using monochrome and colour cameras. After evaluating different sensor integration concepts, we present a preliminary design of the UGV including integrated sensors.

Evaluation of thermography-based automated delamination and cavity detection in concrete bridges

“…Moreover, if an area, detected as damage within the IR data, belongs to a detected graffiti, vegetation, or dirt within the RGB data, it is possible, that it is not a delaminated area. Apart from the damage detection, we plan to integrate the FLIR Vue Pro R on a mobile robotic platform, whose concept was presented by Merkle et al, 22 together with a LiDAR system to directly obtain LiDAR point cloud data with projected temperature information. Thereby, the system can detect and reference both cracks and delamination damages.…”

Semi-automatic 3D crack map generation and width evaluation for structural monitoring of reinforced concrete structures

“…This requires mission planning which can be either manually defined or automatically derived by the bridge's CAD data or point cloud data in combination with set parameters including sensor and lens specs, minimum or maximum working distance, and the maximum camera angle to the bridge surface. Different approaches and concepts for automated inspection using UAVs (Angel Ortega et al, 2020); (Bolourian and Hammad, 2020); (Bono et al, 2022); (Chen et al, 2019); (Ivić et al, 2022); (Shi, Mehrooz and Jacobsen, 2021) and UGVs (Charron et al, 2001); (Merkle, Schmitt and Reiterer, 2020a); (Peel et al, 2018) already exist. Bridges usually require simultaneous localization and mapping (SLAM) due to missing Global Navigation Satellite System (GNSS) below a bridge either based on cameras or Light Detection and Ranging (LiDAR) for navigation.…”

Digitalisierung von Bestandsbauwerken mit KI

“…B. Straße, Wiese, Fluss, Schlucht oder Wald, bedarf es je nach Brücke entweder oder sowohl als auch eines unbemannten bodengestützten (UGV) und eines luftbasierten Systems (UAV). Ein mögliches UGV zur Brückenerfassung ist das von den Autoren entwickelte „Autonome mobile robotergestützte Monitoringsystem für Großstrukturen“ (Amy) [1], das in Bild 3 zu sehen ist. Amy wird in der Lage sein, Brückenbauwerke und andere Großstrukturen autonom und kooperativ so zu erfassen, dass sowohl Geometrie als auch Schäden und weitere Zustandsmerkmale dokumentiert werden.…”

“…Schlucht oder Wald, bedarf es je nach Brücke entweder oder sowohl als auch eines unbemannten bodengestütz ten (UGV) und eines luftbasierten Systems (UAV). Ein mögliches UGV zur Brückenerfassung ist das von den Autoren entwickelte "Autonome mobile robotergestützte Monitoringsystem für Großstrukturen" (Amy)[1], das in Bild 3 zu sehen ist. Amy wird in der Lage sein, Brücken…”