SURVEY-GRADE DATA ACQUISITION AT HIGHWAY SPEEDS
VEHICLE-MOUNTED LASER SCANNING
Martinez Geospatial owns a state-of-the-art Optech Lynx SG1 Mobile Mapper™ system for acquiring high-density, survey-grade, three-dimensional (3-D) point data and high-resolution digital imagery while moving with the flow of traffic. The system can be mounted to either our customized SUV or our heavy-duty Hi-Rail truck for roadway, railroad, or cross-country data acquisition. Some common applications for mobile LiDAR include pavement condition assessments, resurfacing projects, corridor improvement design, sign inventories, catenary surveys, and ADA (Americans with Disabilities Act) compliance surveys.
Our mobile LiDAR system is capable of collecting x, y, z, and intensity values for up to 1.2 million points per second. This rapid, remote data acquisition allows potentially dangerous locations, such as roads, railroad corridors, airport movement areas, and other high-traffic areas to be surveyed quickly, safely, and accurately with minimal expensive and inconvenient traffic control measures. We have extensive experience acquiring mobile LiDAR data for bridges, tunnels, and corridors of a wide variety of sizes and terrains, including concrete interstate highways, bituminous residential streets, gravel rural roads, and grass ditches and berms.
The Mobile Mapper’s on-board Inertial Measurement Unit (IMU) and dual-antenna Global Navigation Satellite System (GNSS) receiver provide high relative accuracies even without a local control network. Alternatively, pre-set targets or existing features clearly identifiable in the point cloud can be surveyed to obtain high absolute accuracies referenced to a geographic or local coordinate system and/or vertical datum. Mobile LiDAR data can also be seamlessly integrated with high-definition static terrestrial laser scanning (HDS), airborne LiDAR, conventional survey, and/or aerial photogrammetric data.
The immense volume of data collected by our mobile LiDAR system creates a highly-detailed and accurate 3-D record of the site conditions at the time of the survey. The high density of data points allows the viewer to see a true 3-D representation of the scanned area rather than just a series of nodes or symbols from traditionally-collected discrete points. This added visualization significantly increases the user’s understanding of the project area, resulting in a more complete, accurate, and timely final product.
We use the processed mobile LiDAR data to create planimetric and topographic maps, surface models, spatial models, and various visualization products. Our experienced and highly-skilled technicians extract the 3-D locations of the visible features directly from the point cloud in a true 3-D stereo environment. Even 2-D features, such as paint markings, can be identified and collected from the point cloud because of the unique intensities of their laser returns.
The high level of detail apparent in a mobile LiDAR point cloud, combined with the geo-referenced digital imagery, also allows for accurate tree classification and sizing, sign inventories, catenary surveys, and bridge clearance measurements to be performed in the office rather than in the field. Using the mobile digital imagery to colorize the point cloud can also aid in correctly identifying specific types of materials and underground utility markings.