Why are AEC firms looking to use off-the-shelf geospatial data?

There are lots of reasons that you may want to look at options beyond in-house data collection. Maybe your project focuses on conceptual design and doesn’t require survey-grade accuracy, or a tight turnaround or remote site means your field crew will have trouble working an upcoming project into their already-overbooked schedule. Or, maybe you’re still in the process of getting your in-house data collection program up and running! Whatever the case, you still need to acquire quality site data and develop final plans that are as accurate as the data will allow ‒ and quickly. 

What benefits can AEC firms gain by using off-the-shelf geospatial data?

The good news is there are a host of companies working to make widespread, high-quality geospatial aerial imagery and LiDAR data available to all. Off-the-shelf geospatial data repositories are saving AEC firms time and money and broadening their reach by allowing them to reduce or even skip the hassle of fieldwork and stream or download the geospatial data they need. And the best part? These files can be uploaded directly to AirWorks for fast and accurate AI feature extraction and linework.

How can AEC firms evaluate and compare off-the-shelf geospatial data?

Of course, before jumping in and grabbing off-the-shelf geospatial data, you need to understand your project requirements and potential limitations on your available data sources vs. survey-grade drone data. Here are some things to consider when exploring your options:

Ground Sample Distance (GSD)

In aerial and satellite imagery, GSD refers to the distance between the center points of pixels on the ground. In other words, the lower the GSD, the higher the image resolution. Sensor quality and altitude both factor into overall clarity. Imagery collected from manned aircraft and weather balloons typically fall in the 3-4 inch (7-10 cm) GSD range; sub-3 inch (7 cm) GSD is considered exceptional. Providers may also offer slightly lower resolution (6-12 inch, or 15-30 cm, GSD) for when maximum detail isn’t a priority. Satellite imagery typically falls in the 12-inch (30 cm) and above range. Understand what resolution your project requires and then double-check what providers are offering.

Point Density

For LiDAR point cloud data, the point density of a laser scan is the 3D equivalent of GSD. The higher the point density (in points per unit area), the higher the resolution and the more accurate the 3D model will be.

Positional Accuracy

How close is what you’re seeing in the imagery to where it is in real life? Don’t be afraid to ask, as accuracy varies from provider to provider. Here are some terms that might be helpful when evaluating:

• RMSE: Root Mean Square Error, compares expected with measured data and indicates how far off an identified feature may be from the actual location. The lower the RMSE, the better the accuracy.
• 5m CE 90: This term indicates 90% confidence that a given feature is within a 5-meter radius of where indicated on the image.

Refresh Frequency

How current does your data need to be? Some aerial services ensure their libraries are updated at least annually; however, rural areas (if offered) may be several years old. On the other hand, satellites are constantly collecting data, making up-to-date satellite imagery fairly easy to come by. Also, if you want to deviate from the data libraries, you can certainly work with providers to get more customized data. 

Coverage

Is your project located in a large urban area or a secluded rural township? If your site is outside of a major metro area, you may have limited options for aerial data. Of course, if you’re looking at a remote site or a location across the world, satellite imagery has got you covered.

Ground Clarity

Before selecting a product, take note of when the aerial imagery was collected. Factors like cloud and leaf cover can affect image quality by obscuring features on the ground. Look for imagery collected during clear days with optional flying conditions and in a season that works for your project. Sometimes you’ll need the most current capture, but older imagery showing leaf-on or leaf-off conditions can also provide fresh perspectives.

Where can AEC firms find off-the-shelf geospatial data?

Off-the-shelf aerial imagery has been around for a while, but its popularity is growing as AEC firms look to expand their footprints and find more efficient ways to understand current site conditions across the nation and around the globe. Aerial and satellite imagery and LiDAR technologies continue to improve, and in addition to their standard online libraries, more companies are offering customized specs and services to clients to meet their needs for image quality and capture frequency. 

When in-house data collection isn’t an option, or you just need a quick-turnaround deliverable, consider grabbing some on-demand data from one of the many companies with aerial imagery or LiDAR online portfolios. AirWorks currently partners with some of the best off-the-shelf geospatial data providers in the industry. By partnering with these companies, we are able to provide data on demand to every client, eliminating the need for on-the-ground data collection if the project allows it. With our data marketplace API integrations, you are able to select your preferred data vendor, the area you would like to extract features from and sumit the project for processing, all in AirWorks Automate and without needing to purchase a subscription from another vendor. Visit our Partnerships page to learn more about our current data marketplace partners.

Below you can explore your options in on-demand aerial and satellite geospatial data:

(Note: Many of these providers offer multiple product solutions that include imagery options such as orthomosaic, oblique, 3D, multispectral, and more. This list focuses on the product solutions that provide off-the-shelf aerial imagery and point cloud data currently best suited for AEC use cases in  AirWorks as of December 2022. Contact providers directly for the most up-to-date information.) 

Nearmap Vertical

If you’re looking for high-resolution, frequently updated orthomosaic aerial imagery in major urban areas, look no further than Nearmap Vertical. Nearmap’s fleet captures sub-3 inch GSD imagery in 1,740 urban and regional areas across the US one to three times per year.

Pros:

• Some of the highest-resolution off-the-shelf imagery on the market
• Coverage areas consistently captured 1-3 times per year

• US coverage limited to urban areas 

Nearmap is currently part of AirWorks’ Data Marketplace. You can learn more about the partnership and how you can place orders in AirWorks Automate™ with Nearmap imagery here.

EagleView Reveal

With sub 3.3 GSD, Eagleview Reveal advertises 4x more detail than standard aerial imagery. Eagleview Reveal’s coverage is impressive, touting 1 billion images in both urban and rural areas, covering 98% of the US population.

Pros:

• Very good resolution at 3.3 inch or better
• Option for 6 inch GSD for large areas where maximum detail isn’t required
• Widespread urban and rural coverage in the US

• Coverage refresh frequency could vary up to several years depending on location

Vexcel Data Program

Vexcel is an industry leader in aerial camera systems and photogrammetry software. With the Vexcel Data Program, the company is leveraging their state-of-the-art UltraCam equipment and UltraMap photogrammetry software to capture and create a portfolio of aerial data from around the globe. With aerial imagery in 26+ countries plus widespread urban and rural capture in the US.  

Pros:

• High-quality sub-3 inch GSD in urban areas
• Wide coverage, including 99% of the US population and 26 countries
• Established reputation in aerial imagery technology and processing software

• Annual capture for urban areas, but less frequent collection in rural areas

HxGN Content Program Aerial Imagery

With Hexagon, you get an imagery database covering the entire US. A big player in statewide imagery initiatives, Hexagon’s HxGN Content Program works with each state to meet their individual spec needs for resolution, revisit rates, and seasonal captures (leaf-on, leaf-off). Hexagon’s rigorous data processing provides some of the most accurate and clear deliverables in the industry.

Pros:

• Thorough QC means high positional accuracy with minimal artifacts and distortions 
• Full US coverage in data library

• Off-the-shelf data in current library may be several years old, depending on location
• Relatively low GSD for US coverage compared to other aerial imagery providers

Nearspace Labs 

Conscious of your carbon footprint? Nearspace Labs gathers data via a zero-emission weather balloon equipped with Swifty, their high-altitude image capture robot. With Nearspace Labs, you can get competitive quality aerial imagery without negative environmental impacts caused by aircraft or satellites.

Pros:

• Carbon-free option for aerial imagery collection
• Quarterly refresh rates

• Competitive GSD, but not the highest resolution imagery on the market

VeriDaaS Data Library

VeriDaaS is one of the few data vendors that provide high-quality LiDAR data. They advertise exclusive use of L3 Harris Geiger LiDAR sensors that have unmatched accuracy and point cloud density for large area coverage. For now, the VeriDaaS data library is relatively limited, with coverage only in select areas where they have completed projects. Still, their repository is constantly growing as they complete new projects across the US.

Pros:

• High quality, large area LiDAR data  
• Unlike aerial imagery, Lidar can penetrate vegetation and foliage, giving a true ground surface elevation

• Limited coverage areas in off-the-shelf data library
• LiDAR only, no aerial imagery (verify project requirements prior to selecting)

Maxar Basemaps

If your project doesn’t demand a significant level of detail, high-resolution satellite imagery could be a valid option. As a high-performance satellite manufacturer, Maxar leverages its own interstellar fleet to collect imagery from around the globe. For large areas, work with their standard, annually updated Vivid Imagery Basemap, or get a customized, current Dynamic Imagery Basemap with updates per your schedule. 

Pros:

• Global coverage
• Customizable refresh frequency (quarterly, semi-annually, annually)

• Potentially not as detailed as manned aircraft imagery collected at lower elevations

Planet Select Basemaps

Planet leverages the world’s largest commercial fleet of satellites to provide clients with customizable Planet Select Basemaps based on their SkySat imagery. Clients have complete control over the area of interest (AOI), refresh rate, and final deliverable parameters.

Pros:

• Global coverage
• One of the most customizable refresh frequencies, offering quarterly down to bi-weekly

• Lowest resolution of reviewed products

Up42

A subsidiary of Airbus, Up42 is unique in that its data library offers a mix of high-resolution satellite, aerial, drone, and IoT data, as well as processing algorithms. By providing a marketplace of data, Up42 is a one-stop-shop that can help you find the geospatial data that fits your need. 

Pros:

• Global coverage
• Wide variety of geospatial data available on one platform (satellite, aerial, drone, etc.)

• Mostly satellite data, resolution likely not lower than 11.8 in (30 cm)