EVO Explorer - Data Visualization and Measurement
Published On: January 18, 2021
Our overriding goal in the small Unmanned Aerial Systems (sUAS) division of our company is to produce a set of solutions that allow customers to very efficiently augment traditional survey tools with high efficiency sUAS solutions.
After experimenting with a wide range of tools, from fixed wing drones with Sony cameras to automatic toe extraction software, we decided, in 2019, to build a fully integrated but modular system called True View®.
This is quite a challenge but one that is really coming together. Our goal is to provide an extremely well-integrated set of tools from sensors through data processing and delivery. The tools are, for the most part, modular, allowing you to use the elements needed to support your particular type of business without other tools getting in the way.
One of the areas we are addressing is how you deliver data to your customers (or, if you are an owner-operator, how you internally use data). Most end-user customers are, of course, primarily interested in what they contracted for such as a raster elevation model, stockpile inventories (volumes), contours and so forth. However, we think there is value in providing end-users with tools that allow them to browse data sets in new ways.
Enter EVO Explorer
EVO Explorer is a new software licensing level we are developing. This will be a free viewer aimed at users who want to review data collected by a True View sensor (including True View Guest Sensors such as the Phantom 4 RTK). Data that will be available in the viewer include colorized 3D point clouds, ortho imagery (if you decided to run photogrammetry on your True View data set), vector line work and Web Mapping Services (WMS) backdrop layers. The primary aim of EVO Explorer is visualization and measurement.
Our 3D Imaging Systems (3DIS®) were designed from the ground up to tightly integrate cameras, allows rigorous colorization of the laser point data. In addition to coloration (and, of course, normal photogrammetric exploitation) the original photos offer great value in inspection scenarios.
During post-processing within EVO, we compute the full positional information for each photo collected by the sensor. We use this information for colorizing the LIDAR point cloud.
We are now adding custom tags to images that allow us to encode this full position, orientation and calibration information directly in to the photo's metadata header (called the Exchangeable Imager Format, EXIF, packet); we are calling this tagging "True Pose."
True Pose images will include a standard categorization as to the anticipated accuracy of the image, from crude navigation position to high accuracy "pose" based on photogrammetric block bundle adjustment.
True View EVO Export Tool
As I write this note, our development team are adding an export tool to True View EVO. This tool, encapsulated in our new Project Manager, will allow you to select the data layers in an EVO project that you would like to include in an EVO Explorer package. Once created, you will be able to deliver the EVO Explorer data package to your customer along with a copy of EVO Explorer. Your customer will then be able to easily visualize the project area on a modest capability Windows desktop computer.
What Can A Customer Do with True View EVO Explorer?
A customer with True View EVO Explorer will be able to import an Explorer package and use the resultant data for project viewing/inspection and some basic measurements. EVO Explorer includes our new Image Explorer functions (the first versions have already been released).
Image Explorer allows the user to click a 3D point such as a LIDAR point (or a feature vertex) and view all of the images that "see" that point. For example, in Figure 1, I clicked on a LIDAR point that extends above a dam spillway to determine if this is a feature or an extraneous noise point. Image Explorer automatically shows all images that see this point. I have Image Explorer set to limit the view to the 10 nearest images. A cross hair of the selected 3D point is projected in each image. Adding these image views to the visualization platform clearly shows that this is not noise but a steel rod extending up from the access ladder.
Figure 1 : Image Explorer Note that the pointing fidelity will be a function of the quality of the camera pose data - very high in a True View 3DIS, lower in a True View 250 (since we are not using a survey grade IMU) and lower still in a Phantom 4 RTK or P1 on an M300.
As a side note, we are adding some basic photogrammetry data collection tools to True View EVO that will allow you to collect feature points from imagery. This was initially driven by the need to do operations such as precisely place wire attachment points to insulators, a job that is a bit tough to do with just LIDAR data. Using the imagery, you will be able to select the desired location in two images that "see" the location and our photogrammetry algorithms will derive a 3D point. There are quite a few situations where this will become a valuable tool.
I see EVO Explorer as an important addition to the True View ecosystem. Not only does it look cool to review data in such a rich visualization environment but it also adds differentiation for you, our customer. Imagine not only delivering a site survey to your customer but also a data set with viewer that allows your customer to do data exploration.
Our overall goal with the True View Ecosystem is to continue to add value that matters to you. This value ranges from efficient post-processing workflows through tools such as Explorer that allow you to differentiate your approach to project delivery from your competitors (or, if you are an owner-operator, to improve your efficiency). Look for more interesting and useful additions to True View EVO as we move through 2021!