In my previous article I highlighted the importance of ground control for aerial drone surveying. You really can’t provide a GIS ready product unless it is coordinated by ground control. Or can you? Now I am not going to start advocating not using ground control but what if you can’t acquire ground control for your given area of interest. Are there other options?? Well yes there are. They are not as accurate as supplying surveyed ground control but they will provide a product which can be used in your system if you just need to view a mosaiced image.
In my position I talk to a lot of different clients about their requirements for drones. I hear of clients wanting high resolution aerial photography, elevation models, performing volumetric analysis, outputting point clouds for updating engineering designs, change monitoring and inspection scenarios. Every client has different thoughts and ideas on how they best make use of their investment. In all of these great ideas I often find that there is a great void between the understanding of what a client is looking for and their understanding of what is achievable.
Whether you purchase a helicopter, smaller quad copter or a fixed wing drone, all are delivered a flight control unit and flight management software. You’ll often though have to supply your own Smart Phone or tablet to run the software. However, it is not until you decide on exactly what you want to use the drone for, does the realisation of what is really required to achieved those results become apparent. If you are going to use it for talking single aerial pictures or video then the manual flight controller might be sufficient, however if you want to be able to use the drone for comprehensive orthomosaics or elevation modeling then there are key considerations that are required.
Do you often have to georeference raster datasets? Do you find a lot of time is consumed with setting up control points?
Georeferencing was introduced with ArcGIS Pro 1.4 and has the capability to speed up your georeferencing workflows. Auto georeference allows you to automatically georeference your raster dataset to a referenced raster dataset (this can even be a basemap from your Portal or ArcGIS Online). The automated control points are based on the spectral signatures of different locations across the images, so this method is best suited for aerial and satellite imagery which are similar in nature.
In my previous articles on GDA2020 I have highlighted some of the considerations that organisations need to have when migrating to the new datum and reasons why Australia is deploying a new datum. These I hope have at least prepared you for what’s about to come.
In March Geoscience Australia released an interim paper
regarding the definition of GDA2020 and its relationships to GDA94 and the International Terrestrial Reference Frame 2014 (ITRF2014) using similarity transformations. This provided the foundation for including the new datum into the Esri suite of products.
Shortly Geoscience Australia will release the full definitions for the GDA2020 datum and the NTv2.0 high resolution grid files for the accurate transformations from GDA94 to GDA2020. In preparation for this Esri Australia, Esri and Geoscience Australia have been working together to have the definitions and transformations available in the ArcGIS software suite. Esri is due to release an update for their ArcGIS 10.5.1 and ArcGIS Pro 2.0 suite of products. We anticipate this to be available mid to late June. These will be the first Esri products to include the GDA2020 definitions and transformations.
The R-ArcGIS Bridge is a little-known secret to improving your methods of geostatistical analysis. By integrating ArcGIS and R you can have the best of both geospatial and statistical platforms. With the R-ArcGIS Bridge you and I can now perform and visualise comprehensive statistical analysis directly in ArcGIS Desktop.
Why would you use R?
R is a powerful platform for solving big data science problems. R is both an open source language and programming environment, widely used for statistical analysis. R offers an online repository with 6,400 statistical problem-solving packages.
The R-ArcGIS Bridge is a way to load your spatial data into R, or, create custom Geoprocessing Tools in ArcGIS that leverage the capabilities of R. The Bridge can be directly connected to either ArcGIS Pro (version 1.1+) or ArcMap (10.3.1+), and R (3.1+) or RStudio. The R-ArcGIS Bridge can then be used with pre-existing tools written in R, without the need to learn any code!
There are several uses of R-ArcGIS Bridge:
- Use R functions to read and write spatial data
- Convert between data types
- Solve complex geostatistical problems
- Write, configure, and modify an R script to be executed from a Geoprocessing tool
- Share an R script with others as a toolbox
How do I get started?
In previous blogs, I have spoken about how imagery can be utilised within the ArcGIS Platform and how it can be analysed. Through all this it has been about imagery can be viewed downstream. What about the prepossessing or specialised analysis not through web services? Well this is where ArcGIS Pro comes in.
In 2017 Esri has stated that their goal is for ArcGIS Pro to be functionally equivalent or better than the current toolsets in ArcMap. To this end in ArcGIS Pro 1.4 Esri have included a new core tab, Imagery. Core tabs are always on and accessible unlike layer specific tabs which only appear when an entry is selected in the Table of Contents.
A quick way to automate making multiple maps covering a large area is through Data Driven Pages. Whether you are trying to follow a road, or if you want to grid an area and show sections on individual maps, there are ways to automate this in ArcGIS so that you have a consistent maps.
There are multiple ways to use Data Driven pages for automated map production.
I have outlined 3 different scenarios where you may find it easier to create maps using data driven pages than individually
Following a Line Feature
1. Search for the ‘Strip Map Index Feature’ Tool in the Search Window
2. Set tool parameters
Layer = Line you would like to follow
Length = the page dimensions you would like to be displayed