Mar 24 2020
3:30 pm - 4:30 pm
UAS Technology Topics
Track Names: Tuesday 3:30 - 4:30, UAS TECHNOLOGY TOPICS
Session Date: Mar 24 2020 3:30 pm - 4:30 pm
Aligning Project Specifications with Lidar and UAS Technologies: The New Hybrid Product Approach
Lidar is becoming a main stream technology when it comes to roadway engineering, asset management and mapping. However, each of these activities require different lidar data specifications and therefore different lidar system capabilities. Mobile lidar or MMS is well known for its accurate and dense points clouds, but it is more often only driven on paved roads and with substantial costs for mobilization. Aerial lidar is characterized with its wider coverage, very much beyond road rights-of-way, and its acquisition efficiency. However, data from aerial lidar is less accurate and has fewer points, i.e. lower density, as compared to data from the Mobile lidar. Imagery-based points cloud from Unmanned Aircraft System (UAS) based imagery and SfM phtogrammetric software is proven to bridge the gap between MMS and aerial lidar requirements in areas of the project where it is proven useful. Many projects, specially transportation projects, need elevation data with varied positional accuracy. MMS data with design-grade accuracy needed for the pavement maintenance and upgrade, the less accurate UAS-based points cloud for the areas outside the pavement along the right of way for ditches and drainage modeling, and less dense aerial lidar, usually offered on line by state wide programs, for the watershed surrounding the corridor project for hydrological studies and design. Currently, the labor-intensive field surveying techniques are used to model the topography in the right of way areas. We are finding that UAS-based points cloud and imagery can eliminate the good portion of the field surveying needed for the right of way topographic modeling for corridor projects. The presentation introduces a new hybrid approach to roadways engineering by fusing data from MMS, UAS, and aerial lidar. Knowing when to hire certain lidar technology is a challenge for many surveyors and engineers within the transportation community.
UAV Mapping and Automation in Transmission Line Inspection
UAV-mapping systems have proven to be a reliable approach for inspecting distribution and transmission powerlines. Use of these systems is expanding rapidly demanding ever increasing automation in data collection and processing, lower-costs, and more accurate geospatial solutions for decision-making over many kilometers powerline survey data. Because of the nature of the application, UAV payloads in use typically consist of many sensors, including GNSS, GNSS/IMU, LiDAR and a variety of cameras including RGB, thermal, hyperspectral and video. In most current systems, data processing is conducted separately for each individual sensor, and the output of one sensor is simply used as an input for the next sensor being processed. For instance, the workflow begins with the LiDAR sensor for identification of powerlines and the vegetation around them, then RGB and thermal images are used for visual inspection. The output of this process is a report with images on the areas identified for further inspection and possible repair. In this paper, the authors present a practical algorithm developed for powerline inspection automation that was tested on over 900km of powerline corridors surveyed in Chile between 2018-2019. The algorithm is based on multi-sensor integration, accurate time-tagging and accurate geo-tagging of the sensor data. Once vision sensor data is accurately georeferenced, the workflow makes use of deep-coupling integration of the sensors. In our deep-coupling approach, LiDAR and the RGB/IR data are coupled, providing more powerful data processing where LiDAR data, and the DTM obtained from it are used as the base for mono-image processing and a ray-tracing technique is used to process single images in pixel coordinates. The RGB data is used for real-time colorization of the LiDAR data adding a strong visual component to otherwise plain LiDAR point clouds which enhances feature extraction, classification and interpretation. In this new approach, the on-board G
Large Area Mapping by VTOL UAV Lidar
This presentation uses a real case to show that large area mapping with high accuracy results can be achieved using a cost-effective and fashionable method – UAV Lidar. August 2019, a single mission of 128 km² area mapping was successfully accomplished in north Bangkok, Thailand, using the VTOL Lidar technology from LidarSwiss Solutions GmbH. The goal of the project was to find the most efficient and cost effective method to acquire 1:1000 accuracy laser and digital imagery for a 30,000 km² flood plain study. The presentation showcases how the project was planned, the equipment involved, mapping products achieved and result assessed and accepted by the customer. At the end of the presentation, an economic analysis of large area mapping using VTOL Lidar vs conventional Lidar on manned aircraft is also discussed. The presentation will show that VTOL Lidar technology is mature and capable to perform large area mapping projects in developing countries.
LidarSwiss Solutions, GmbH
Q&A and panel discussions with session presenters
There will be a 15 minute Q&A /panel discussion with the presenters of the UAS Technology Topics session.