Best Practices for Large Airborne Mapping Projects
- 1. Best Practices for Large Airborne Mapping Projects A Focus on Airborne Lidar Acquisition and Processing
- 2. Time Constraints of Large Area Lidar Mapping Projects • Acquisition • Seasons • Leaf off • Snow cover • Weather patterns • Water levels • Other project commitments • Data checking • Processing • Sensor calibration enhancement • Block processing • Long processing durations • IT requirements • Delivery • Not all data is ready at once. Block delivery is to be expected • Sometimes large areas need to be delivered to multiple clients / constituents
- 3. Best Practices of Large Area Lidar Mapping Projects • Sensor Selection • Many Lidar sensors are built for different specialty purposes • Flight Planning • Density • Signal strength • Maximum line length • Collection • Relying on base stations is very limiting • Crosslines per mission • Online status tracking • Processing • Data check • Calibrationenhancement and geometric corrections • Sensor model enhancements • Boresight • Line to line • Mission to mission • Block to block • Geometric corrections • Debiasing • Point classification – need an SME who can create adaptive filters • Breaklines – need good software • Derivative product generation – usually batchable • QA/QC – most important
- 4. Solutions for Technological Challenges of Large Area Lidar Mapping Projects High Performance Computing (HPC) • Multithreading applications • Intelligent RAM management • Very fast storage media • Fast network connections • Balancing Network Attached Storage (NAS) and local disk data locationing for processing • Distributed Processing • Cloud based if needs are intermediate and spikey • OnPrem if needs are more continuous • Hybrid is an option but can get tricky and expensive. It is sensitive to WAN data transfer interruptions.
- 5. Solutions for Technological Challenges of Large Area Lidar Mapping Projects • One or more workers are needed that are willing to schedule their work around data processing which does not always conform to 8-5 M-F. Remote working technology helps with this. • Keep the data at the processing location. • Internal software development to supplement COTS lidar processing and QA/QC software is a big advantage.
- 6. Thank you Matt Bethel Director of Operations and Technology at Merrick & Company Lidar Division Director for ASPRS matt.bethel@merrick.com