In the fall of 2016, Martinez Geospatial (MTZ) was contacted by the Minnesota Department of Transportation (MnDOT) to perform survey-grade Mobile LiDAR collection and compilation for Interstate 94 from Nicollet Avenue to Single Creek Parkway. The 10 mile stretch of I-94 required a survey-grade Digital Terrain Model of the highway surfaces for use in a new concrete overlay for the highway. MTZ was ready to deliver.
Nearly 100 miles of data collection
The project area is complicated. There are multiple major interchanges: I-394, I-694, Hwy-100, and Lyndale and Hennepin Avenue. There are overpasses, tunnels, bridges, on-ramps, off-ramps, and frontage roads. Mobilization took careful planning.
Nonetheless, MTZ was able to collect the Mobile LiDAR in 10 days of field time during off-peak hours of traffic and driving each direction multiple times for full coverage. In the end, MTZ had 157 drive lines in total resulting in nearly 100 miles of Mobile LiDAR collection.
In addition to Mobile LiDAR, MTZ utilized static High-Definition Laser Scanning (HDS) technology to capture the interior of the Lowry Hill Tunnel. The decision to use HDS was made to nullify concerns with GPS outages through the tunnel for the Mobile LiDAR system. The HDS data was collected overnight during the annual cleaning, and was used for DTM collection. Throughout the entire project, the highway was never shut down due to MTZ’s data collection methods.
MTZ provided MnDOT with the following:
Raw and processed Mobile LiDAR
Raw and processed HDS LiDAR
Raw and processed digital imagery from Mobile LiDAR system
MicroStation DGN of DTM breaklines extracted from point clouds
Survey Control information (provided by KLJ Engineering)
MnDOT Bridge Office Vertical and Horizontal Bridge Clearance Reports
The project was completed on schedule for MnDOT. The project information tied to the I-35 Transit Access project where MTZ also was contracted for Mobile LiDAR and Digital Terrain Modeling for MnDOT.