Friday, January 25, 2019

Lab 3

Introduction Questions Part 1

Why are proper cartographic skills essential in working with UAS data?
When working with UAS data, essential Cartographic skills can include but are not limited to knowing how to measure ground control points, the desired elements that should be presented on a map, and knowing the kinds of graphics and pictures that are easy for people to see and understand.
  
What are the fundamentals of turning either a drawing or an aerial image into a map?
A scale bar, the drawing itself, and a title, are the fundamentals of turning an image into a map. To make the more map more user friendly, a key, a locator map, a direction arrow, and metadata are usually included as well.

What can spatial patterns of data tell the reader about UAS data? Provide several examples.
 Below is a short list of hypothetical examples that to answer the above question.
  • A UAV with a temperature sensor scanning a runway and finding values cooler on the outer  edge of the runway compared to the inner part of the runway. 
  • A UAV with an infrared sensor detecting heat coming from a crack while it inspects a bridge.   
  • A UAV inspecting crop yields and being able to detect the parasites that are harming them.
  • A UAV inspecting a tectonic plate over Alaska and noting the features of it. 
What are the objectives of the lab?
The objectives of the lab are to make a map template to reference for future labs, to better navigate Arcmap, ArcPro, and learn how do a small project in Arc Scene. 

Working with the Data Methods Part 2

What key characteristics should go into folder and file naming conventions?
Characteristics such as having folder names run general to specific, along with specifying files in accordance to your preference are ideal methods of  organization. In addition, characteristics such as the date, project name and file type are important characteristics as well. 

Why is file management so key in working with UAS data?
File management is key with working with UAS data, because if you do not manage your files correctly, sensitive information could be lost, unorganized files could result in poor data analysis, and you could lose overall time as a consequence of the mismanagement.

What key forms of metadata should be associated with every UAS mission?
Key forms of Metadata can be found in Figure 1. These include, but are not limited to the date of the flight, the pilot of the flight, the UAS platform, the sensor of the UAS, the altitude flown, the ground control GPS, the ground control coordinates, and the UAS coordinates. A summary of these items along with an example flight are highlighted in the chart in Chart 1.
Chart 1: Metadata Summary
Create a table that provides the key metadata for the data you are working with
Add a basemap of your choice. What basemap did you use? Why
For this project I chose the Topographic basemap because I am familiar with it in our lecture demonstrations, it isn't too distracting to work with, and I like that it’s simple. 

Using the Add data icon, or Arc Catalog, bring the orthomosaic and the DSM into ArcMap
Build and Calculate Statistics for each data set and insert the statistics into a table.                       As seen in Chart 2, are the statistics gathered from the orthomosaic. With the exception of the classes category, each number was rounded to the nearest hundredth. 
Chart 2: Building and Calculating Statistics

What is the difference between a DSM and DEM?
According to gis.stackexchange.com, a Digital Surface Model (DSM) is an elevation model that includes the tops of buildings, trees, powerlines, and any other objects. According to USGS.gov, a Digital Elevation Model (DEM) is a representation of the terrain (bare-earth) with elevations at regularly spaced intervals. 

Go into the Properties for the DSM and record the following descriptive statistics.Cell Size, Units, Projection, Highest Elevation, Lowest Elevation. Enter those statistics into a table. Why are these important? Descriptive statistics are important because they help complement the overall metadata. Without statistics, we would have less information about the mission which could harm or even ruin the data processing process. An example of what descriptive statistics look like can be found in the Chart 3.
Chart 3: Descriptive Statistics Example

Generate a Hillshade for the DSM. Then set the original DSM to a color ramp of your choice and set its transparency to your choice over the shaded DSM. What does hillshading do towards being able to visualize relief and topography?
To help visualize the effect of hillshading, compare Figure 1 to Figure 2 and note the differences in cracks. As you can see,  the DSM with hillshading can greatly enhance the ability to visually detect cracks compared to the DSM without hillshading.
Figure 1: DSM Without Hillshading
Figure 2: DSM With Hillshading
Use the swipe tool to compare what you see in the orthomosaic to the DSM. How does the orthomosaic relate to what you see in the shaded relief of the DSM? 
In figure 3 you will notice the DSM partially shaded while using the swipe tool. This relates to the shaded relief of the DSM by demonstrating that you can have both Figure 1 and 2 together for immediate comparison of the same picture yet with different details depending on what shade you prefer to view it in.
Figure 3: A combination of Figures 1 and 2

Arc Scene 3D DSM Questions Part 3

What is the purpose of vertical exaggeration? What settings do you have for your data?
The purpose of vertical exaggeration is to provide a 3D reconstruction of the image. For the data in Figure 4, I set my vertical exaggeration to “calculate from extent” mode which in this case was 2.37259. 

What color ramp did you use? Why?
I used Red to Green Diverging, dark because it appeared simple and user friendly compared to the other color options. 

What are the advantages of using ArcScene to view UAS DSM data vs. the overhead shaded relief in ArcMap. What are the disadvantages?
ArcScene is advantageous for viewing 3d data, and rotating the image. In addition, it is relatively easy to learn. ArcScene is disadvantaged compared to ArcMap due to it lack of features and will be phased out soon. 

Find a zoom setting and angle you like in ArcScene and export the image as a jpeg or file of your choice.Is this export a map? Why or why not?
As seen in figure 4, is the image of the exaggerated DSM. Although it looks relatively complex, this is not a map because it does not have a title, or scale bar.
Figure 4: Digital Surface Model "Calculated 1.5 Extent"

Building a Map Part 4

In this section, an example of a map template had to meet the following requirements:
  • A North Arrow
  • A Scale Bar
  • A Locator Map
  • A Watermark
  • Data Sources
In Figure 5: I included a map that meets all these requirement,

Figure 5: Wisconsin Mine Site

Conclusions Part 5 

When you compare the images from the beginning, you can see that the data gathered by a UAV  can yield significant advantages to a GIS user and cartographer. When processed correctly, atmospheric conditions, surface images, and spatial data can better document can be combined with other various types of metadata to form a cohesive working set of information that can enable us to better understand the sciences involved in Earth's processes. Since UAS is relatively new to geospacial science, it will be difficult to pinpoint if it will remain relevant in the future.As a tool for cartography, it can easily provide detail for specific locations that can not be compared with satellites (yet).

Since UAS is restricted by flying laws, battery life, and data management problems, using it as a tool in any field will have challenges, Nevertheless, advancing technology has the potential to enhance it's development as well. Although it is difficult to say where the direction UAS will go, it will have to be incorporated with sophisticated technology in order to survive. This includes better data collection, and better data itself. Some forms of data that I believe will factor into this innovation include data from swarming, data from artificial intelligence and data from real time information systems. Although these are extremely broad concepts, think about that given the fact that that UAS as a whole has already been applied to ideas never thought of before.




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