Drone Mapping – Business Models Revisited

I am currently attending the 2017 NSSGA/CONEXPO exposition.  One of the keynotes from the National Stone, Sand and Gravel Association (NSSGA) conference focused on the rate of change of technology in the mining industry and the scope of operations that are covered by these technologies.  Of course, one of the examples was the use of drones.  The gist of the discussion was that some of these technologies are in their formative stages; we do not yet fully appreciate the scope of operational affect they will have but to prosper, knowledge of these systems must be internalized.

One thing is very clear – frequent and repetitive mapping will be required to support the automated machinery that is now appearing on advanced sites.  You cannot program a haul truck for autonomous operations if you do not know the location of the road!  Complicating this issue is the fact that the road location changes nearly daily due to the operation itself.

This future trajectory says that mine site mapping will need to become an internal operation.  It will be impractical from both a logistics and cost perspective to outsource drone mapping services.  A second strong consideration is the rapidity with which drone technology is changing.  I think amortizing the cost of a drone over more than 12 months is just not realistic.

Drones are simply platforms for cameras and other sensors (for example, profilers, laser scanners and so forth).  A drone without a sensor is a fun toy to fly but it is not going to have much use in operations!  I am very excited about new platforms from commercial drone companies (mostly DJI).  These new drones include decent cameras in that they now incorporate larger sensors and hybrid shutters.  You can do a reasonable job of mapping with these yet still use them for inspection videos.

DJI Inspire

So I think what we are seeing is the beginning of the end of the purpose-built drone.  You will be able to purchase drones from DJI (and perhaps others) that are nearly a consumable.  You can use the same drone for inspections as you use for mapping.  This is a very important consideration since this greatly simplifies the training of users.

The bottom line here is this – we are seeing the beginning of drones as an everyday tool for mining, industry and construction.  The proper model is going to be internal control of not only flying the systems but also processing the data.  When you need a quick check of a pulley on a conveyor, you will want an internal staff member to quickly fly the inspection job and post the resultant video.  No need to have a third-party system or contractor involved.  It just complicates the flow and adds expense.  This is really the motivation behind our Bring Your Own Drone (BYOD) Mapping Kit.  It lets you use a low-cost drone such as the DJI Inspire to do serious mapping without a lot of complicated leasing or outsourced data processing arrangements.  It also allows you to use the same platform for inspection that you use for mapping.  Give us a call to see how well this solution will meet your specific needs.

FacebookTwitterGoogle+LinkedInShare

AirGon Partners

We spent a lot of time in November and December of last year (2016) developing a coherent strategy for our AirGon business. As you know from prior newsletters, AirGon LLC is our small Unmanned Aerial Systems (sUAS) subsidiary. We have been developing technology for the past three years aimed at implementing and improving sUAS (or, more commonly, drone) high accuracy mapping. Our focus has been in four major areas:

  • Hardware for RTK/PPK grade geopositioning (the AirGon Sensor Package)
  • Software tools for data processing (Topolyst)
  • Reckon, our Amazon Web Services (AWS)-hosted data management and delivery portal
  • Workflow best practices for project repeatability
  • Production Services for customers who do not want to do their own processing

Addressing the sUAS market is a new challenge for us. There is a surprisingly small overlap between our traditional LIDAR/Photogrammetry marketplace and the new drone business. After a few years in the trenches and hundreds of mapping projects, we are rationalizing our business into three different Partner categories. These are delineated by the type of customer:

Technology Partners – These are customers who purchase technology from us to either use for their own internal operations or to offer services. The technology in our portfolio related to sUAS mapping includes:

  • PhotoScan and Pix4D point cloud generation software
  • Topolyst, our purpose-built point cloud exploitation tool for data from sUAS Laser Scanners (LIDAR) and/or data from dense image matching
  • Bring Your Own Drone (BYOD) Mapping Kit, a collection of software that enables serious mapping with a variety of third party drone hardware from low cost DJI Inspires to professional grade senseFly (eBee) fixed wing drones.
  • Reckon, our Amazon Web Services-hosted site data collaboration and delivery portal. Reckon is a subscription product that allows web-based collaboration between the service provider and end user (who may be one and the same)
  • Various hardware components
  • Consulting services, tailored to needs

Network Partners – The AirGon Network program is an emerging part of our AirGon business. It comprises drone mapping services experts who use our technology for data capture, processing and delivery. Network Partners always interact with their AirGon Network client base via Reckon. We offer regular best practices training, exposure to end-use customers and referrals. We can also provide data processing services to those who wish to focus only on flying. This is a program that requires qualification.

Enterprise Partners – These are end use customers of drone mapping services. An AirGon Enterprise Partner can be as small as a single stockpile yard to as large as a multi-national mining company. Enterprise partners generally engage with us via our CONTINUUM concept, a model that allows a customer to tailor a drone mapping solution that exactly fits their desired business model. For customers who wish to do their own data collection, we offer subscription-based back office processing services. For customers who want to outsource data collection and processing, we link Network partners who are the best match for the desired services and locations.

Please get in touch with use (info@airgon.com) if you are serious about high accuracy drone mapping – we would love to work with you!

What Miners Want

I attended the Commercial UAV Expo in Las Vegas at the end of October.  I gave a talk entitled “Mine Site Mapping – One Year In.”  This talk was on our experiences with performing mine site mapping services with our AirGon Services group.   Our services group is primarily about Research and Development (R&D).  We use our engagements with mining companies to discover the products that they need, accuracy levels and, most of all, how to reliably create these products.  These experiences inform both the development of our technology (the MMK, Topolyst, Reckon, the BYOD Mapping Kit) but also help us develop best practices for both collection and processing.

As I prepared for this presentation, I reviewed the mine site mapping projects we have performed over the past several years to tabulate the products our customers have requested.  These turned out to be, in decreasing order of popularity:

  • Site Volumetrics with a priori base line data
  • Site Volumetrics with no prior data
  • Site contours (“topo”) – 2 foot interval
  • Site Contours – 1 foot interval
  • Time series volumetrics (“borrow pit”)

In every case, the customer desired a site orthophoto.  In fact, they usually want an ortho of the entire site with analytic products of a subsection of the mine site.

I thought in this month’s section, I would review these products from the acquisition and processing point of view.

 Volumetrics with baseline data

I have written a few articles about injecting a priori data into a mapping project.  This is the situation where, at some time in the past, the customer has done a site survey and wants to use these data as the bottom surface of stockpiles.  Their primary desire here is for consistency from inventory to inventory.

An example of this, a large limestone quarry that we fly, is shown in Figure 1.  Here baseline data as well as a reclaim tunnel model have been provided to us as a DWG data set.  The illustration of Figure 1 shows these data being used by Topolyst to create a 3D base surface.

 

Figure 1:  Bottom Data with reclaim tunnel model

Figure 1: Bottom Data with reclaim tunnel model

The primary challenge that we have when receiving a priori data is the accuracy of the data.  We often find that these data were obtained by traditional stereo photogrammetric collection techniques so we do not have a point cloud from which to assess accuracy.  Now, done properly, stereo photogrammetry produces survey grade data.  Unfortunately, much of this a priori data was collected with the surface obstructed by existing stockpiles; in other words, it was not a stockpile free base data mapping.  This means that the stereo compiler had to estimate locations under the existing data.  We find that in most cases, these estimations are simply linear interpolations from one side of the obscured area to the other.  We often find these bottom models extending above the current surface.  It is difficult to tell if the data were incorrectly modeled or if the ground has actually changed from the time the baseline data were collected.

A second big challenge we have with these data are a lack of knowledge by the provider as to the exact datum to which the data are referenced.  We are often concerned with elevation differences of just a few centimeters.  The Geoid model really matters when you are approach survey leveling accuracy goals.  We have found, on more than one occasion, a priori data with an incorrect vertical model.  This usually occurs (at least in the USA) as a result of using the incorrect NAD83 to WGS84 transformation.

Over the past year, we have added a lot of refinements to how Topolyst handles this a priori data.  Those of you who do LIDAR or photogrammetric processing will immediately recognize this as the problem of introducing “breaklines” and “mass points” into a model.  LP360 (Topolyst is just a variant of LP360) has always been a very strong product in terms of breakline modeling.  We have added a few features in this area to improve the modeling as it typically applies in UAS mapping.  We are now at the point where we really do not have any software issues with this sort of modeling but the interpretation problems will always remain.

This type of modeling requires:

  • Direct geopositioning (RTK/PPK) on the drone
  • Multiple surveyed check points on the site for data validation
  • Strong modeling tools such as Topolyst
  • A conference or two with the customer to understand the models
  • A lot of patience when defining stockpiles

Volumes with no a priori data

Here the customer is interested only in the volumes of the piles, without regard to location.  The deliverable is generally a spreadsheet with volume, material type, density and tonnage.  Of course, our customer deliveries are via our cloud data platform, Reckon, so we want the toes to be correctly georeferenced.

If you leave out the correct georeferencing (meaning you compute the volume of the pile but do not necessarily try to align it with an existing map), you have the sort of processing offered by a myriad of web-based solutions such as Kespry.  Under this business model, you typically upload the raw drone images which have been georeferenced by the navigation grade GNSS for x, y and the drone barometric altimeter for elevation.  This typically provides horizontal accuracy on the order of several meters and vertical accuracies at about 5 meters.  So long as the camera is properly calibrated, this methodology leads to volumetric accuracies that are accurate to within about 5%.

We never do these projects without some check points.  These are surveyed image identifiable points that we use to check horizontal and vertical accuracy.

The biggest issues we have encountered with this type of project is the definition of the stockpile toe – it is somewhere between comingled piles, it traces along an embankment such as the pit, the stockpile is in a containment bin and so forth.   There requires a lot of careful toe editing in a three dimensional visualization environment such as Topolyst.

We never have issues with accuracy because we always fly with a direct geopositioning system.  For our MMK, it is a Post-Process Kinematic, PPK, GNSS system.  For the senseFly eBee, it is an onboard RTK system.  We always lay out some checkpoints for project verification.

A very clean mine site with stockpiles sitting on a surface is nearly non-existent (except in our dreams).  While you sometimes encounter sites where you can just manually draw a toe, these sites are nearly always at inventory transfer locations, not working mines.  In fact, of all the mine sites we have surveyed, we have encountered only one “groomed” site (see Figure 2).  Even at this site, the upper left and lower right piles required some disambiguation (wow, that’s a big word!) work to separate the pile edge from encroaching vegetation.

Figure 2: A "groomed" inventory site

Figure 2: A “groomed” inventory site

 Site Contours (“topo”)

A surprising number of customers want contours.  As you know, these are elevation isolines at a particular interval.  Most customer want either 2 foot or 1 foot contour intervals.  These data, in DXF or DWG format, are used as input to mine planning software.  I find this a bit odd since I would think by now that this downstream software would directly ingest a LAS point cloud or at least an elevation model.

Contours are always absolutely referenced to a datum (a “Network”).  This can be a local plant datum or, much more commonly, a mapping horizontal and vertical datum such as a state plane coordinate system for horizontal and NAVD88 with a specific geoid model for vertical (at least in the United States).

You can tie to the datums using either direct geopositioning with onboard RTK/PPK or you can use dense ground control points.  I personally would never collect data that must be tied to a datum without having a few image identifiable checkpoints.  Unfortunately, this means that you will need at least an RTK rover in you equipment kit.

A good rule of thumb for contours is that the accuracy of the elevation data should be at least three times the accuracy of the desired contour interval.  This says if you are going to produce 1 foot (30 cm) contours, you need 4” (10 cm) of vertical accuracy relative to the vertical datum.  When you measure your checkpoints, don’t forget to propagate the error of the base station location (which you might be deriving from an OPUS solution).

Preparing a surface for contour generation is perhaps the most tedious of mine site mapping work.  It is generally the only site mapping you will do that requires full classification of ground points (the source for the contour construction).  An example of 2 foot contours within a mine site is shown in Figure 3.

Figure 3:  An example of 2' contours

Figure 3: An example of 2′ contours

Sites with a high degree of vegetation in areas where the customer wants contour lines will have to be collected with either manual RTK profiling (very tedious!) or with a LIDAR system.  You simply cannot get ground points with image-based Structure from Motion (SfM).  No surprise here – this is why LIDAR was adopted for mapping!

If the customer does not want to pay for LIDAR or manual RTK collection, the vegetated areas should be circumscribed with “low confidence” polygons.  You can either exclude the contouring completely from these areas or classify the interior to vegetation and let the exterior contours just pass though the region.  In any event, the customer must be aware that the data are quite inaccurate in these regions.

The SfM algorithm gets quite “confused” in areas with overhead “noise” such as conveyors and vegetation.  This confusion (actually correlation errors) typically manifests as very low points.  You will need to find and clean these points prior to contour generation.

Conclusions

Product generation for UAS mapping requires a lot of front-end planning.  This planning needs to be product-driven.   If you customer (you, yourself, perhaps) needs only volumes with no tie of the toes to a datum, you can get away with no control so long as some other information such as camera calibration and flying height are correct.  By the way, we recommend never collecting this way since you are precluded from doing any meaningful time series analysis.

On the other hand, most meaningful data (that is, you can quantify the accuracy relative to a datum) will require a very careful control strategy as well as a rigorous processing workflow with the right tools (meaning Topolyst, of course!).  No matter what geopositioning strategy you employ, you should always have some independent methods for verifying accuracy.

If all of this seems a bit daunting, you can get assistance from us.  Remember, our services group is really our R&D lab.  Our real goal is to sell technology to owner/operators and production companies.  No matter what drone you are using, you can always avail of our consulting services.  We have gained a lot of experience over the past few years, mostly by first doing the wrong thing!  Save yourself this time and money by engaging with us!

 

 

 

3DEP, LP360 Toolbox and AirGon

I am looking for the month of May – it seems to have disappeared without a trace!

We recently visited with the Tennessee Office of Information Research (OIR) in beautiful Nashville, Tennessee. The OIR is the coordinating state agency for a USGS 3DEP LIDAR (3 acronyms in a row – not quite a record!) acquisition project. Under this program, the state of Tennessee will be flown at Quality Level 2 (2 points per square meter) over a four year period. The initial collection (slated for this fall) will encompass some 11,500 square miles, covering 27 counties.

3DEP is an excellent opportunity for state and local government agencies to pool their financial (and often technical) resources to obtain point cloud data. By spreading the cost across a spectrum of stakeholders, a surprisingly large amount of data collection can be accomplished.

Our discussions with the OIR led naturally to a conversation about how LIDAR data are used in GIS and engineering departments. We covered the usual suspects such as flood plain analysis, basic 3D visualization, site planning and so forth. By the end of the conversation, I was convinced (as usual) that every single state and local government GIS workstation should have access to a current image and current 3D (e.g. LIDAR point cloud in LAS format) backdrops. Why would anyone find it acceptable to be without a cross-sectional view of their municipal data on an ad hoc basis? Mainly because they have never had this level of information available. You never miss what you have never had!

When we returned to the office, we decided to put together, once and for all, a package of material for folks who are either contemplating acquiring LIDAR data or those who have access to LIDAR data. We will develop use cases and return on investment information for the range of applications that make sense for these data. If you have some novel ideas and particularly case studies, please work with us. Obviously we want to sell more software but we believe a rising tide lifts all boats. We need to get the tide (meaning the understanding and effective use of LIDAR data) rising first!

Speaking of software, we hope to have our experimental release (EXP) of LP360 available for download by the end of this month (June). The developers are doing fine. It is me who always throws a wrench in the delivery schedule – “let’s get return selection added to the new Live View dialog before we release…” Speaking of Live View, this is a new dynamic filter in LP360 that lets you change class, return and flag filtering on the fly. You are really going to like this new feature!

While we try to make features in our tools easy to use, the LIDAR tools on the market still tend to be toolbox oriented rather than workflow specific. For this reason, it is very important to participate in training if you hope to realize a maximum return on your investment. We offer a range of training (and consulting) from web based to on-site. In addition, we have our Huntsville-based LP360 training coming up in the fall.

On the AirGon side of things, we have been talking to a lot of potential clients who can make immediate use of small Unmanned Aerial Systems (sUAS) mapping. We offer a complete helicopter-based metric mapping kit in the AV-900 MMK. This is garnering a lot of interest since it provides a turn-key solution of hardware, software and training for doing jobs that have an immediate high return on investment such as stockpile volumetric analysis. However, we also offer just the piece parts for those who wish to assemble their own system. For example, if you have decided on a small wing type sUAS such as the eBee from SenseFly, LP360 for sUAS is still your best option for extracting volumetrics (anyone who has tried to do a multi-pile site using the point cloud generation software shipped with these systems will readily agree!). In addition, AirGon Reckon is the best product in the market for hosting and delivering mine site orthos and volumetric reports. By hosting our volumetrics delivery system in Amazon Web Services, we relieve you the need to worry about data delivery to multiple offices, data backup and security.

Summer promises to fly by just as quickly as the spring. We are attending a number of conferences such as the ESRI meeting and the Transportation Research Board AFB-80 summer meeting. If you are attending one of these, please look us up. See you in July!

Drones, Metric Mapping and RTK

We have been very busy this first third of 2015 with software development (as we always are).  The thing about software is that it is never static.  It is either undergoing new additions or entering the end of life phase.  We have had a very big focus on ensuring that our products are optimized for LAS 1.4 support as this is the new requirement of the USGS.  Additionally, we like to use LAS 1.4 in our mine site workflows since it supports a few nice capabilities that were not in LAS 1.3.

This is definitely the year of the drone.  Every major geospatial hardware firm has announced a drone system for remote sensing (some for metric mapping).  While the USA is inching along toward some usable drone rules, other countries have clear rules in effect and drone mapping is becoming a standard survey/mapping tool.

We are garnering a very high interest in AirGon’s Metric Mapping Kit (MMK).  This solution provides everything you need to do uncontrolled mapping projects using a small Unmanned Aerial System (sUAS) except a processing laptop computer.  Add in your own surveyed control points to reach survey grade accuracy.

Speaking of the Metric Mapping Kit, we will be hosting a AV-900 MMK workshop in Toronto, Canada on June 11th and 12th.  Thanks to Jim Giordano, we will be presenting live flight demonstrations at VicDom Sand & Gravel as well as an in-depth look at mission planning and post-collection data processing.  Our focus will be on drone-collected volumetrics. Personal protection equipment (steel toed boots, hardhat, safety vest and safety glasses) are required.  Remember that a passport is required for travel between the USA and Canada.  Space is extremely limited so sign up early!

We have been (in a joint project with Applanix, a Trimble Company) researching the use of Post-Processed Kinematic (often erroneously called Real Time Kinematic, RTK) control solutions.  Obviously everyone flying a sUAS for metric mapping purposes would like to dispense with the tedium of deploying ground control.  We will publish the results of our efforts as a white paper when the work is complete.  My goal is a recipe, if you will, of the methods that are appropriate for a given desired accuracy level.

We will be posting an experimental (EXP) release of LP360 (all license levels) within the next few weeks.  Those of you on software maintenance will be able to download this release via the “Check for Updates” option under LP360 Help.  There is a separate article in this newsletter that provides a highlight of the new features.

Till June – Best Regards,

Lewis

GeoCue Group News – May 2015