250 likes | 275 Views
Surdex Corporation is a leading aerial mapping company headquartered in the St. Louis, MO area. With over 50 years of experience, a dedicated team of employees, and a wide range of advanced mapping equipment, Surdex offers cost-efficient and high-performance LiDAR processing and aerial mapping services. From LASER measurements to GPS data reduction, Surdex provides accurate terrain modeling, contour generation, and hydrological analysis for diverse projects.
E N D
Surdex Corporation • Surdex headquartered in St. Louis, MO area • Over a half-century of photogrammetric mapping • ~100 employees • 8 aircraft – 4 Cessna 441 (Conquest) Turbine Aircraft • 3 Intergraph Digital Mapping Cameras (DMC) • 1 UltraCam Xp Wide Angle • 5 film cameras • Leica ALS 50-II LiDAR • Very progressive R&D • Large amount of proprietary algorithms and software • Focus on cost-efficiency and performance
LASERMeasurements (Range, Angle, Time) LiDAR Processing GPS DataReduction GC Check Position Attitude GPS/IMU Processing IMU X,Y,Z Point Cloud Classification AUTOMATIC Classified Points (Bare-earth, veg/building) 2D Edit LASER Intensity, RGBOrtho Photos MANUAL TIN Stereo QC / Edit DataThinning Stereo Images TIN Break-lines DTM Surface
Bare Earth DEM Calculations • Identify man made structures • Determine ground elevation at edges • 2. Identify vegetated areas • Search for ground points within area • 3. Identify open areas • 4. Interpolate between available points • 5. Filtering and clean-up First Return DEM
Automatically extracted Bare Earth DEM • Ground surface with vegetation and man-made structures removed • Critical for terrain and hydrology modeling Bare Earth DEM
Raw vs. Edited LiDAR Contours Contours from raw LiDAR data Contours from raw LiDAR data with photogrammetric edits
Types of LiDAR DTM & Contours • Level I • Classified to bare earth, automated generation • Level II • Classified to bare earth • Automated, minimal cartographic edits • Level III • Classified to bare earth • Break lines added to hydrology • Similar cartographic edits of Level II • Level IV (Specified contour accuracy) • Classified to bare earth • Full break line enhancement • Full cartographic edits
Level 1-2 Surface Level 3 Surface
Contours from LiDAR Data • Understand the various data available • Understand the cost associated with additional editing and processing • Discuss the project requirements with your LiDAR provider • Get ready for A LOT of data!