Michael Baker's very own Kevin Pomaski (UAS Services Director), is highlighted in a recent Nevada DOT video discussing the deployment of UAS to perform emergency assessments of road damage due to recent flooding.
Stephen
Mobile LiDAR systems employ vehicle-mounted lasers, cameras and GPS/INS navigation systems to capture highly detailed 1:1 scale, 3D topographic data for surveying and engineering applications. Michael Baker International became an early adopter of Mobile LiDAR technology in 2009, and expanded our capacity in 2014 and 2015 to increase our fleet to four Optech Lynx SG1 Mobile LiDAR systems. Ask about custom solutions for utilities, rail, transportation, airports, pavement, photologs, and more.
Showing posts with label Rendering. Show all posts
Showing posts with label Rendering. Show all posts
Friday, March 3, 2017
In the News...
Stephen
Thursday, April 21, 2011
No Place for Survey Crews
Earlier this year, we were tasked to perform a Mobile LiDAR collection of an Interstate tunnel (2 lanes in each direction - measuring 0.8 miles in length). The tunnel is in a heavily trafficked urban corridor where closures required by traditional surveying, even in the early morning hours, were completely out of the question.
Due to the constant, unrelenting traffic, we performed the collection shortly after midnight. We collected each of the 4 travel lanes at or slightly below posted speed limits - slowing down or speeding up to minimize laser shadows from other vehicles. Following the collection, our LiDAR processing staff and Applied Technology Group produced the final products.
First, our LiDAR processing staff adjusted the passes to ensure coincidence. Then they made quick work of removing other vehicles from the point cloud. Then, they turned over the tiled point clouds for modeling.
In the article I wrote for LiDAR News last week I made the statement "if you can’t see it, the system isn’t measuring it." The below image is directly disputing that statement - which I don't quite mind in this case.
Perhaps what is most fascinating to me is not that the system captured this information, but how it will be exploited by our client.
Cheers!
Stephen
Due to the constant, unrelenting traffic, we performed the collection shortly after midnight. We collected each of the 4 travel lanes at or slightly below posted speed limits - slowing down or speeding up to minimize laser shadows from other vehicles. Following the collection, our LiDAR processing staff and Applied Technology Group produced the final products.
First, our LiDAR processing staff adjusted the passes to ensure coincidence. Then they made quick work of removing other vehicles from the point cloud. Then, they turned over the tiled point clouds for modeling.
 |
| An image of the point cloud with vehicles removed, but tractor trailer model added. Notice the pothole in the bottom left hand corner of the image. |
 |
| Our Applied Technology Group utilized the cleaned point cloud to create a rendering of the tunnel in MicroStation. |
 |
| The image shows a cross-section of the tunnel. Notice the arc above the "box" tunnel. The arc represents returns from the actual tunnel ceiling (extent of bore) that were measured through small (1") joints in the false ceiling. |
Cheers!
Stephen
Friday, October 1, 2010
Modeling Bridges from Mobile LiDAR Information
I often tell people that the products derived from Mobile LiDAR data are only limited by one's imagination and willingness to push the envelope. On that premise, we recently performed work on an interstate including overpasses and ramps. In addition to the typical MicroStation planimetrics and DTM, Baker's Applied Technology (AT) group was enlisted to prepare models of collected bridges. While looking at the progression of the modeling, keep in mind that the information was collected at posted speed limits.
Below is a simple slice of the Mobile LIDAR point cloud representing the North/South bound lanes of travel. I quickly added height clearances which I used to calculate an approximate slope. At each of the bridges, we created subsets of the point cloud to minimize processing during the modeling phase.
From the subset point cloud, our AT staff began modeling the environment. Presented below is a wire-frame of the modeled solids (modeling involves developing a mathematical representation of 3-dimensional features). The ground is represented as a Triangulated Irregular Network (TIN). In a wire-frame, the outlines of the features are depicted with the point cloud still visible.
Finally, textures and colors are applied to modeled features. The shadows cast are incredibly detailed - notice the guardrail and pillars on the right-hand side. The next step is to add cars, collected roadway signs and other ancillary information - perhaps our team can throw a model of the Mobile LiDAR unit in there rolling down the interstate.
For more information on Baker's Applied Technology and the services they provide, please contact:
Below is a simple slice of the Mobile LIDAR point cloud representing the North/South bound lanes of travel. I quickly added height clearances which I used to calculate an approximate slope. At each of the bridges, we created subsets of the point cloud to minimize processing during the modeling phase.
From the subset point cloud, our AT staff began modeling the environment. Presented below is a wire-frame of the modeled solids (modeling involves developing a mathematical representation of 3-dimensional features). The ground is represented as a Triangulated Irregular Network (TIN). In a wire-frame, the outlines of the features are depicted with the point cloud still visible.
After the wire-frame, a hidden line model is presented below. Basically the shapes and surfaces shown in the wire-frame are filled. The solids depicted have no texture, but the model begins to take shape.
Then a draft of the model is prepared for visual inspection. The impact of grass in the median is clearly visible. Since we started without the luxury of a classified point cloud, our AT staff cleaned the surface using MicroStation InRoads (can also be completed in GeoPak). Obviously starting with a classified LAS containing bare-earth and vegetation points, would have saved a little time for our modelers.
Perhaps the coolest image, in my opinion, is the Ambient Occlusion (AO)image shown below. The software we utilize provides the ability to create shadows, define sun angles and change perspective depending on time of day. I also like that it shows an immense amount of detail on the guardrails and other features.
By adding vehicles to the model, it provides a sense of scale and depth. The vehicles in the AO image are used to determine the shadows they cast on the model as well.
Finally, textures and colors are applied to modeled features. The shadows cast are incredibly detailed - notice the guardrail and pillars on the right-hand side. The next step is to add cars, collected roadway signs and other ancillary information - perhaps our team can throw a model of the Mobile LiDAR unit in there rolling down the interstate.
For more information on Baker's Applied Technology and the services they provide, please contact:
Senior Designer
3D Design and Visualization
Michael Baker Jr. Inc.
412-269-2987
Alan and the rest of the group have exceeded our expectations time and time again. Perhaps down the road I'll share more of their superior work modeling Mobile LiDAR data.
Subscribe to:
Posts (Atom)