Field Activity #8: Arc Collector

Introduction

This weeks field activity will have us creating our own data collection parameters for a feature class in ArcMap through the design of our own fields and domains.  Though this many seem like a simple task, assuring you have all of the fields and domains which are pertinent to a study poses to be a complicated task.  Prior planning and thought required to have a perfectly set up feature class, fields, and domains requires in depth planning and commitment to design perfectly.  After the creating of our feature class I will be utilizing the Arc Collector application with my Android phone to collect the data point location and the attributes associated with the location.


Methods

The first portion of this activity we were introduced to what different parameters are available when setting up domains in ArcMap.

A domain is a range or value of valid attributes which can be used in data collection to help streamline the process and aid in accurate values in the fields.

Domains can be set to various Field Types including, short and long integer, float, double, text, and date.  These field types allow you to maintain consistency of the data values.  Consistency is especially important when multiple people could be collecting data.  An example would be if a group was collecting street address data and the manner in which different people would collect the word "Avenue".  The word avenue could be recorded in a number of ways such as: "Ave.", "ave.", "Avenue", "avenue",...ect.  Each variation would register differently in ArcMap and would not register all of results when searching for "avenue".  You can also use domains to set an allowable range value, such as for temperature to assure you don't end up with 300 degrees Fahrenheit when you intended to type 30 degrees.   Using domains eliminates errors which are time consuming to fix later and allows data to be collected faster in the field when done properly.

To practice setting up a domain for the collection of points on the campus.  I selected to map some of the signs around campus.  I set my domains up to what I thought would thoroughly cover the variations of signs around campus.  Before completing the assignment I decided to collect a few points to see how well it was set up.  The first sign I collected information about proved I had set up my domains and fields poorly.  The first issue was I choose specific colors and did not allow for an "others" color variable.  My first sign was a color I had not input in my domain.  My second issue wasn't related to my domain but my preparation.  I had set a "height" field for the signs, but I did not have any form of measuring device to collect the information properly.  I collected a few other points with no other noticeable issues.  With these lessons learned I felt I was ready to design and prepare my geodatabase and domains for the second portion of the assignment.

I chose to survey businesses around the Eau Clarie area on Thanksgiving day, and record if they were open or closed.  I chose to record the date, whether the business was open or closed, if the business was open what time were they open till, what time I recorded the data, and the type of business being recorded.

I created a new geodatabase with in ArcMap and began creating my domains in the Database Properties menu (Fig. 1)

For the date domain, I set the only allowable date as Thanksgiving Day (11/26/2015).  For the open domain I set a coded domain to Yes or No.  I chose to set coded domains for the types of businesses, including Bar, Grocery Store, Gas Station, and Other.  I attempted to set the open till field to allow any time coded answer but something went wrong with this domain and I will be investigating what happened.  The time collection domain was set improperly as well, as I could only type in decimal form and could not use a semi-colon.  I am not sure if this is an ArcMap issue or with the manner in which I set up the domain field.

(Fig. 1) Domain setup for my assignment in ArcMap.

Then next step was to create a feature class for the point locations of the businesses.  After creating the feature class I assigned Field names in the Feature Class Properties menu.  I added Date, Time, Open, Opentil, and Business_Type to menu.  After add the fields I applied the above domains to the attributes to assist me in proper data collection (Fig. 2).

(Fig. 2) Feature Class Properties with Field Name and Domains applied.

My next step was to create a map in Arc Collector which will I will be able to connect with through my application on my phone.  The map will allow me to be able to display the data I collect.   To understand the step required to create the map I was directed to http://doc.arcgis.com/en/collector/ by my Professor.  This was the same process I used when I practiced collecting data around the campus. Next, I created a map for my Thanksgiving Business Survey using the streets basemap from ArcGis.


Once the previous steps were completed I was ready to go out and collect my data information.  The weather was not ideal, as it was sleet/snowing and the temperature was around 30 degrees Fahrenheit. Due to the in-climate weather all of my data points were collected from inside of my car.

After collecting all of my points I went back to the map I created in ArcGis to confirm all of my data was properly stored.  From the map window I could see my attribute data for the point locations I had entered (Fig. 3).

(Fig. 3) Display of Thanksgiving data points in ArcGis.com under my personal content.

I searched around to locate a way to classify the way the point locations were displayed on the map but I was not successful.

Discussion

The seemingly easy task of creating a geodatabase with a single feature class, and attributes does not seem like a important or particularly complicated task.  However, it is both important and complicated.  The extra work you do ahead of time will save you endless hours in the end of a project.

In my case I made errors in both of the fields and domain I created.  The errors I made could eaisly be over come by taking notes and editing the fields when I arrived back to my computer with the proper field notes being taken.  However, had I taken a little bit more care and done some preliminary scouting I would have been able to eliminate almost all of the errors I encountered.  I feel this is probably the most important take away from this assignment.  You can sit at a computer and contemplate all of the factors you will run into in the field but you will never think of them all. Giving yourself the flexibility to add notes and "other" fields to properly account for the variables you didn't think of is a must.

Additionally, I believe if you have the opportunity to head out into the field and "scout" or test your field and domains you should.  This will quickly bring issues to your attention and you can fix the issues before the actual data collection occurs.  Examining other databases similar to your may also bring attention to issues you have not thought of if a scouting mission is not feasible.

I am assuming you can download or extract the data from Arc Collector for use in ArcMap but I have not experimented with that.  I was disappointed when I was unable to change the way the point locations were displayed on the map.  I believe the majority of this needed to be preset when the map was created online.  This is just one more preliminary step you must complete to be successful with Arc Collector.

Conclusion

Preparation is the key when it comes to creating a geodatabase and feature classes from scratch.  The more precise work you do ahead of time the more time you NOT have to spend in the end fixing errors in the data.  Taking quality notes and having an "other" field is also crucial due to unscripted occurrences in the field.

Field Activity #7: Topographical Survey

Introduction

Field activity #7 was a combination of 2 separate classes focusing on 2 different surveying techniques and tools to create a topographical survey.  Our class utilized a dual-frequency GPS the first week and a Total Station the second week.  These devices are both survey grade units.  We will be comparing the accuracy and the useability between them.

Dual-Frequency GPS

TopCon HiPer SR, TopCon Tesla, and a MiFi are three parts/devices to the dual-frequency GPS we will be using in this exercise.  To achieve the accuracy the units are capable of all the components must be used together.

The TopCon HiPer SR unit is a GPS receiver/antenna (Fig 1).  The TopCon has a static horizontal accuracy of approximately 3mm and a static vertical accuracy of approximately 5mm.

(Fig. 1) TopCon HiPer SR

The TopCon Tesla is a field controller allowing you to do a multitude of functions (Fig. 2).  For this exercise we will be using it to collect our location and elevation while it is paired with the HiPer SR.

(Fig. 2) TopCon Tesla handheld unit

To record the most accurate data possible the HiPer must be angled perfectly vertically.  Attaching the HiPer to a tripod fixed with a level we were able to accomplish a near perfect vertical angle.  To properly record the elevation (Z value) we must know what the height of the HiPer is.  The tripod we used was 2 meters in length, and there was a parameters in the Tesla to account for this.


Total Station

The total station utilized the Hyper, and Tesla from the Dual Frequency section above along with a Topcon Total Station (Fig. 3), and a prism (Fig. 4).  The total station is mounted on a heavy duty adjustable tripod, and the prism is mounted on a mono-pod pole with a level.

(Fig. 3) Similar unit to the Topcon Total Station we utilized during this exercise.

(Fig. 4) Prism which is mounted on top of a pole to gather point locations.

Methods

Dual-Frequency GPS

For this section of the lab I was assigned a partner.  It just happened to be Casey from a few previous field activities.  Before we could collect and data we had to complete the initial setup of the Tesla unit to conduct the survey with the Dual-Frequency GPS.  After creating a new job with in the Tesla unit we set the parameters for our location and use. The parameters we set included but were not limited to Projection: UTM North-Zone 15, Unit of Measurement: Meters and the majority were left to their default settings.

After preparing the Tesla we headed out into the "Mall" area of the University Wisconsin Eau Claire Campus.  Casey and I decided to survey a portion of the stream which runs through campus.  The stream bank offers a fair bit of elevation change and we felt it would display the accuracy better than sublet elevation change (Fig 5).

(Fig. 5)  Study area near the UWEC Campus mall area.

Per the assignment we had to collect at least 100 points.  When we began the data collection Casey was placing and leveling the Hyper and I was operating the Tesla.  She would level the Hyper and give me the go ahead to "Save" the point.  We continued this method for 25 points and then we switched jobs so both of us would get equal experience with both instruments.  We switched again when we reached 50 and 75 points.  Our Tesla registration ran out just before we started the field activity demo, so we were limited to using the Tesla in demo mode.  In demo mode we were only able to collect 25 point per job.  To get around this issue we created 4 jobs to collect our 100 points.

(Fig. 6) Casey collecting the first point with the Dual-Frequency GPS.

After collecting our 100 points we exported the data to a flash drive from the Tesla using the To File feature withing the Exchange menu.  Once on the flash drive we opened the four separate text files of data information and copied the data into one combined file.  Utilizing ArcCatalog I created a shapefile from a XY table  After importing the shape file into ArcMap I used the Kriging interpolation method to create a display of the elevation change of the data points collected (Fig. 7).

(Fig. 7) Display of the dual frequency elevation data using the Kriging interpolation method.

Total Station

The total station started out the same as the dual-frequency survey with the exception of the weather and a new group.  Our professor was nice enough to assign us to groups of 3 since there are so many pieces of equipment to use.  For this section of the assignment I worked with Katie and Nik.  We prepared the Tesla in the same manner as the previous survey.

Using the directions from our professor we used a starting location over a containment box of some sort in the "Mall" area.  This containment box had a point which would not move and would allow ease of leveling the tripod and the total station.

Before leveling the total station we had to collect the location of the total station and our back points. We collected these points in the exact same fashion as the Dual-Frequency exercise.  These points are collected to locate and determine the orientation of the total station.

Once the orientation points were located the total station was leveled and prepared to collect data points.  We utilized the bluetooth capability to connect to the Tesla and collect our data points.  The total station fires a laser at the prism and using the return information it collects the location.  Instead of moving the GPS around like the dual-frequency we just moved the pole mounted prism around and made sure it was perfectly vertical using the attached level.  Once the pole was vertical we aligned the cross hairs in the total station viewer to the center of the prism and used the Tesla to recorded the point location and elevation.

Unfortunately the issue with the Tesla was not resolved by the time we collected points with the total station so we were limited to 25 points for this data collection section.  I repeated the same steps for creating a shapefile and utilizing the Kriging interpolation method to create a display of the elevation.

(Fig. 8) Display of the total station elevation data using the Kriging interpolation method.

Discussion

Being both of the instruments were survey grade I was interested to compare the accuracy between the two.  However, due to some technical difficulties, and weather we were not able to collect data points in the same location for both units.

The dual frequency system is easier to prepare to collect data.  However, if you were going to collect a large number of points in one area it may not be the most efficient method due to having to level the tripod each time.  For the 100 points we collected I feel it was satisfactory and once we had a rhythm it wasn't terrible to level.  If we had to collect 500 or more I would definitely consider using the total station.

The total station takes little more work to prepare between leveling and collecting the back points.  Once you have it set to run though you can collect points in a quick hurry and the accuracy is higher provided you have all the parameters set.

When we were setting up the total station we had issues getting the Tesla to Hyper to collect the OCC and the back points.  This issue took far too long to fix and pressed our group for time to complete the exercise do to a incoming storm and class we had to attend.  Somewhere in the rush we must have missed a parameter.  Comparing the 2 maps above you will notice the dual frequency results are ~30 meters higher than the total station.  This is not the case, as the dual frequency location is lower compared to the area we setup the total station.  There is a number of parameters in the total station which calculate for all of the height dimensions of the equipment and I am guessing one of those was improperly computed or mis-marked.

Overall, both of these units are not complicated to run but they are complicated to run and achieve accurate and proper results.  To become proficient at them I would need a bit more training to understand more of the ins and outs of the setting and parameters within the devices.

Lastly these devices are finicky and can throw temper-tantrums at a moments notice.  The issue we had connecting the Tesla to the Hyper only took restarting the Tesla to fix, but when we turned the Tesla off we could not get it to turn back on.  This happened to multiple groups and even the professor.  I am not sure if this is the case with all of them but it is an expensive tool to have not work properly sometimes.  This is just an example of many of the many connection issues we had.

Conclusion

These field exercise provided me with a great deal of experience in dealing with various surveying components and tools.  This was a big change from many of the "low tech" ways we have been utilizing throughout the beginning of the semester.  To acheive high accuracy the "high tech" method would be my choice.  Though it can throw you a curve ball once and a while with the proper setup you can achieve unparalleled results.

Field Activity #6: Navigation with Map and Compass

Introduction

This weeks lab is a continuation of Field Activity #5 where I created 2 different navigation maps.  Our group of 3 will be utilizing these maps to plot and navigate to 5 different point locations created by our professor at The UWEC Priory.  The 5 points were marked on trees using bright pink ribbon and labeled with the appropriate number.  Our tools for navigation are limited to the UTM map we created and a standard compass. (Fig. 3)  Each person in our group of 3 had a specific job during the navigation process. One person was the compass holder, and pace counter, another persons stayed back to assure the person stayed on the correct course, and the final person was the runner (going wherever they were needed.)  We were given a GPS unit for backup, as from year to year some of the ribbons on the trees seem to disappear.

Methods

To start the exercise our group was given a list of 5 locations with the corresponding UTM coordinates.  Our first step was to plot the points in the correct location on our map.  Each group member plotted their own points on their individual map.  We compared the point locations on each others maps to verify the correct locations.  The list was organized but there was excess information cluttering the page and I read the incorrect number for one of the locations and had to correct it.  We then decided on a starting location which was easily deciphered on our map and plotted it as a point on our map.   After plotting and numbering the points we drew connecting lines between all of the points.

(Fig. 1) Casey and Katie preparing their maps for the exercise.

(Fig. 2) My map with point locations and lines drawn. 

After preparing our map we were given instructions from Dr. Hupy on how to utilize our compass for navigation.  The first step was to take the compass and line the edge of the compass up with the line you wish to navigate.  While holding the compass on the line I adjusted the compass housing (bezel) so the north arrow and the orienting lines on the compass line up with north and the grid lines on the map.  This gave met the correct bearing direction angle to our first point.

The next step was to calculate the distance we needed to travel to reach the first point.  Using the centimeter ruler on the baseplate of my compass I measured the distance from our starting location to point 1.  I measured 8 cm which equals 280 meters in the real world.

With the bearing direction my group member Casey took the compass while standing at our starting point she held the back (opposite end from the direction of travel arrow) of her compass to her chest and rotated herself until the magnetic needle (red) was inline with the orienting arrow (shed) this also referred to as "red in the shed".  With "red in the shed" Casey was now facing in the direction of our first location. 

(Fig. 3) An example of a compass similar to the one we used in the exercise.

From our previous calculation we knew the first point was 280 meters away from our starting location.  Casey stated her pace count from the Field Activity #5 was 67 paces.  This meant she would have to step 187 steps to reach point 1 if the ground was perfectly level.  However, the ground was not level, and our direction took us into the forest.

I had stayed back where we started to make sure her direction stayed true.  This method was only effective until she hit the tree line and then she was gone.  I caught up with her at the tree line and continued to watch her bearing.  Casey walked her 187 steps and we did not see a marker anywhere.  I remained at the location where her 187th step was, while she continued on her bearing direction to see if she could locate the point.  Meanwhile our runner (Katie) was wandering out front of our location to see if she could spot the marker for the point.

(Fig. 4) Casey and Katie searching for the first point location.

It wasn't long before Katie located a marked tree we believed to be the point.  After further inspection of the marker it was not our point.  At this point we were not sure how far off we were, so we consulted the GPS to compare our location to where we should have been.  After checking the GPS we realized we still had not gone far enough in the bearing direction and were off to the east a slight bit.

(Fig. 5)  The first tree we located with a marker, though it wasn't the one we were looking for.

After a short distance we ran into another marker on a tree.  We believed this marker was the point we were in search of.  Assuming this was our first point we consulted the map and calculated the bearing and distance to the second point.    I took the job of pacing and holding the bearing with the compass.  We were at the edge of a very steep ravine so pacing was not going to equal accurate results.  Before I started walking I judged the distance and used my pacing count to estimate how many steps it would take me to walk the distance.  After reaching the opposite side of the ravine and checking my bearing direction I continued on my bearing and pace counting.  After a very short distance Katie (I believe) found a marker on a tree.  Now we were confused again.  We consulted the GPS and confirmed we were at the proper location finally for point 1.  After inspecting the map closer there were topology lines which should have given us an idea we were on the wrong side of the ravine when we thought we had found the point.  (More on this in the discussion)

(Fig. 6)  Casey (Left) and myself (Right) examining the map for navigation from point 1 to point 2. 

Resetting my count and bearing direction we headed for point 2 with our prior calculations. The terrain was difficult to keep a good pace count on and hold your direction.  There was a number of ravines I would have had to cross to keep my bearing true.  I employed the same method of estimating the distance across.  When we arrived at the point where I felt point 2 should have been located, it was not to be seen.  Having been down this road before we consulted the GPS to check and see which direction we were off.  This time we had traveled far enough but our bearing direction was off slightly which put us off to the west a little bit.  We were still at the top of the ravine so we knew we had descend for sure and guess we would have to go up the other side.  When we hit the bottom of the ravine we checked the GPS and it seemed if we had went to far to the east.  After some wondering, we located the tree marker laying in the bottom of the ravine.  Using the GPS we finally located the location of point 2 which was about half way down the ravine slope.

From point 2 we calculated the bearing direction and distance to get to point 3.  Katie took her turn at pacing and holding the bearing direction.  The bearing took us back up the slope of the ravine.  When we arrived where Katie said the location should have been we couldn't just see the location.  After about 30 seconds I located the tree with the marker for the location.  She was almost perfectly inline with the point as far as distance but her bearing was off very slightly.

We used the same procedures for point 4 & 5.  We used the GPS to find location #4 as the marker on the tree was not there.  As we navigated from point 4 to point 5 it was getting close to the end of class time and darkness.  Casey took another turn at pacing.  When we reached were the location should have been we didn't just see it.  For the last time we consulted the GPS and we were not that far off and after a real quick search we decided to head back to the parking lot where we started the activity.  We used our map to get a bearing direction to head in for our return trip.  We successfully navigated back to our origin.

Discussion

This activity was full of learning experiences.  I was familiar with pacing prior to this activity.  However, I had never preformed pacing in terrain which varied in elevation this much.  The majority of my experience was on mowed trails which were relatively flat.  The method which I employed for estimating distance work fairly well but I am sure there is a better method.

The map I created for this exercise left a fair bit to be desired.  Prior to heading out in the field I felt as though the imagery of the trees would be helpful in navigation.  The basemap imagery did not help us locate ourselves on the map while in the forest.  The second issue I had with the map was the topology lines.  The spacing was probably adequate but the labels did not allow quick assessment of actually topology.  I believe using the DEM to create a better basemap and layout for topology would have greatly assisted us in our navigation. 

The 50m grid spacing for the grid lines made it tough to get an exact accurate location of the points.  Add the grid variability with the size of dot we made on the map with the marker and you already have a 10 meter approximation of location.  In the woods this approximation makes it difficult to locate places with foliage still on the trees.  Additionally, I made the grid color fairly transparent as to not hider visibility of the topology lines.  What I did not consider was we had to use these grid lines to set our bearing direction.  Doing it over again I would make them easier to see for a more accurate bearing.  Smaller grid spacing, larger scale, and alternate basemap would have greatly increased our accuracy for navigation.

Despite the issues we had with the first point, overall our navigation was fairly accurate.  I overlayed our track log from the GPS on the DEM and 1-5 point locations.  From this map you can see with the we were in the ballpark of all the point location.  You can see the issue we had locating the second point.  The 5th point which is the one we gave up on due to the darkness is depicted in the bottom of the ravine which we would have not have been able to see from the top.

(Fig. 7) DEM with track log from GPS, and point locations.

I don't feel the above DEM truly shows the elevation changes we encountered while trying to navigate.  I imported the DEM into ArcScene to create a 3D image of the landscape (Fig. 8)

(Fig. 8) 3 dimensional image of the terrain we navigated.

My fellow classmate Peter Sawall who helped me create the topology maps in Field Activity #5 showed me how to created an elevation profile using the DEM (Fig. 8).  You can see from the image the elevation change was significant especially for Eau Claire County Wisconsin.

(Fig. 9)  Topology profile created with ArcMap.

Conclusion

Overall this field activity was very educational in navigation trials and tribulations.  One of the biggest factors which would aid you in navigation is prior planning.  Learning and exploring your landscape prior to heading out into the field will greatly assist you in whatever your endeavors might be.  To be proficient at navigation in the woods, I would definitely need more practice and training.

Make sure to check out my group mates blog post.

Casey's Blog
Katie's Blog

Thanks again to Peter Sawall for assisiting me with advanced features in ArcMap.  Make sure to check out Peter's Blog.