In the presented scenario, an autonomous surface vehicle (ASV) equipped with a laser scanner navigates on a inland pathway surrounded and crossed by man-made structures such as bridges and locks. GPS receiver present on board experiences signal loss and multipath reflections in situation when the view of the sky is obscured by a bridge or tall buildings. In both cases, a potentially dangerous situation is provoked as the robot has no or inaccurate positioning data. A sensor data processing scheme is proposed where these gaps are smoothly filled in by positioning data generated from scan matching and registration of the laser data. This article shows preliminary results of positioning data improvement during trials in harbor-river environment.
Road segmentation, obstacle detection, situation awareness constitute fundamental tasks for autonomous vehicles in urban environments. This paper describes an end-to-end system capable of generating high-quality 3D point clouds from one or two of the popular LMS200 laser on a continuously moving vehicle. Advances in autonomous inspection of subsea facilities using a 3 Dimensional(3D) LIght Detection And Ranging (LiDAR) sensor are examined to illustrate the favorable enhancement of safety, reliability, reduction in risks, economic benefits and superior data products compared to conventional means. These benefits provide operators with significant improvements over general visual inspection by the addition of sensors that produce 3D models of the structure being inspected. Examples are provided illustrating test data from operations conducted from 2012-2013. Supported by funding from the Research Partnership to Secure Energy for America (RPSEA) Lockheed Martin MST teamed with the innovative company 3D at Depth to incorporate their new DP2TM 3D LiDAR onto the proven Marlin® Autonomous Underwater Vehicle. The objectives of the project include: Survey using combination of high resolution 3D Sonar and 3D LiDAR Generation of high fidelity 3D models Detection and localization of structural changes vs. reference model Lockheed Martin has successfully integrated the laser into the Marlin shore based laboratory addressing the challenges associated with coordinating a scanning laser from a moving platform and producing high resolution georegistered images. Testing will be conducted in early 2014 to validate the system in the Atlantic Ocean waters offshore Palm Beach, Florida. Three dimensional georegistered models of an entire scene can be rapidly collected providing a clear vision of the underwater scene along high resolution 3D models of the imaged item. Data collected at sea and in the laboratory will be presented demonstrating the performance of the system. Application to deepwater life of field inspection will be presented with evidence gained from offshore trials. This emergent technology supports Subsea Facility Inspection Repair and Maintenance, Integrity Management Inspections of Marine Risers, Moorings and anchors, Subsea Pipelines, Flowlines, Umbilicals, and supporting subsea infrastructure.