Remote Sensing - Steps to order a map:
Remote sensing can be used on any job site. It’s a great service option as the site gets larger or access is limited (e.g. rail, highways, cleanup sites). Remote sensing includes any methodology where data (e.g. imagery, LiDAR, hyper-spectral, etc) is collected from a distance, usually from the air. GdB uses UAVs (i.e. drones), manned aircraft, and has a library of imagery collected over the years under ideal conditions.
The resulting mapping has given our clients significant processing and time savings.
UAVs are best for hard-to-reach areas, small sites and locales with critical time parameters (e.g. low tide). They are perfect for construction sites that are constantly changing.
Manned aircraft are best suited for very large areas, sites where the general public and/or moving cars are present or areas near sensitive facilities (e.g. airports, stadiums, etc).
Not sure which is best for your project? GdB can help you determine a method to best serve your needs. You can leverage the team’s decades of experience to capture what you need within your parameters. Techniques like:
Heavy front and side overlap to minimize elevation distortion around buildings;
Multiple flying paths and elevations to combine accuracy with coverage;
Slow flights and multiple paths to increase LiDAR coverage;
Bespoke PiPs (i.e. points in pictures) with drive-to coordinates to streamline the control process;
Specialized processing for point classification;
Whatever you need, communication (like always) is key to a successful program. Here are some steps to get the discussion started:
- Where is the site? Provide a detailed map of the required area
- KMZ is a preferred method of receiving this information
- A sketch from google maps works well too
- What is the smallest thing you need to see? This determines GSD (ground sample distance) and flying elevation
- What is the final scale of the mapping. This dictates the overall horizontal accuracy.
- 1”=20’ typical for engineering. This scale captures most details
- 1”=40’ typical for large sites without too much detail. May not capture valves and other details
- 1”=100’ typical for planning-level projects over large areas, like towns and facilities.
- What is the desired contour interval. This dictates the vertical accuracy.
- 5’ Typical for engineering and drainage projects
- 1’ common for site development projects
- 2’ common for wide-area projects where elevation change is not as important
- What is the deliverable?
- Mapping or planimetrics
- Point Clouds
- Are there other factors? Convey anything that is unusual about your site and specific to you.
With this information, our photogrammetrists will better understand your project and can jumpstart the effort. Keep in mind that scheduling is very sensitive when it comes to flying. Clear days are important to fly and there may be restrictions due to weather and air traffic. GdB’s Remote Sensing team can typically provide maps within a two-week window. As peak flying season approaches timeframes may change. And don’t forget GdB’s library of historical imagery when conditions won’t work for you.