Priory Navigation with GPS and Paintball Marker

Introduction

For this exercise, similar to the previous priory navigation, we would be in our teams and be required to reach a number of points.  This time, however, we would be required to hit all 15, not 5, and in addition to carrying a GPS unit instead of a map and compass, we were armed with paintball markers and masks.  

Methods

The GPS made navigation easier, in that instead of having to stop and take a compass reading, we could simply watch our position change on the GPS screen and see ourselves getting closer to the points, which were displayed.  On the other hand, when stopped, having a compass where you can just hold it up and get a reading in seconds is much better than having a GPS where getting to a compass requires a menu. 

The display we had on our GPS unit for this exercise.  The red border indicates the boundaries within which we maneuvered.  The red shaded areas were strict no firing zones.  The pink line traces our path.

The paintball markers made the exercise have an additional layer of tension.  Now, while we were scanning the trees for the orange and white flags, we were also keeping two eyes peeled for the movement of other classmates.  Because of this, we tended to move much slower and more cautiously than we would have if we were not in danger of being seen and fired upon.  Our team engaged in three firefights early on; for the first one, we lay in wait and ambushed an approaching team, and I got hit in the leg from a seated position.  The second engagement, I got the hit on the enemy.  For our third shootout, another of our team was hit.  When a team member was hit, his or her entire team was required to take a one minute time out.  This gave the other team time to move out of the area in search of their next point.

Professor Hupy and students prepping the paintball markers before the exercise commenced.

Each team was required to go to a certain point as their first, but after that, it was up to each team to determine their path.  Our path seemed a good one, taking up down into the ravine early on and then sticking to the edge of the map, working in a circle through the points until we doubled back towards the interior for our last four points.  As I said, our three engagements occurred in the beginning of the exercises; for the latter two hours, when we were on the east side of the course, we never saw another team. 

We had some difficulty on this exercise because of the nature of the gear we were carrying.  The masks would constantly get fogged up visors, making visibility extremely difficult.  To counter this, we had to keep pulling the masks up on our heads.  Doing so also made it easy to breathe, because inside those masks, it is hot and humid and horrible.  Also, the guns, while not heavy, were still a burden to carry around for three hours over rough terrain.   We arrived back at the parking lot at 5:30, not the first ones back and not last, but right in the middle.  Our course was good, but definitely could have been better.

Priory Navigation With Map and Compass

Introduction

For this exercise, we used the map and compass skills that we had learned previously for Assignment #5 in the field.  Thus, the study area is the same as for that entry.

Methods

We started at the parking lot.  We were given a sheet that lists fifteen separate points by the point’s lat/long and elevation.  Each group was assigned a course of five points. Our team marked our five points on the Transverse Mercator map that we had created previously and printed.  Five points does not seem like much.  We double check them.  Two of our points’ elevations do not match between what is listed on the sheet for the point and the elevation on the topo map in the point’s approximate location.  We are unable to figure out what is wrong.

The sheet listing the course points with lat/long and elevation.

The map that we had printed out for our use.

All the same, we start from a light post.  We lay out the map and place the compass on the line between our current position and Point 1.  We orient the north arrow on the compass dial to align with the north orientation on the map.  Lifting the compass off of the map and placing red in the shed, we have our direction.  We head off.  I am the one using the map and compass, while Travis and Jeremy move ahead of me.  I look for a landmark along our distance line and tell them to go to it.  When I reach them, I take another bearing, find another landmark, and send them to it again.  The majority of landmarks will be trees, hopefully distinctive enough ones that they can be pointed out in the middle of a forest.   For Point 1, we head out of the parking lot into the woods.  We walk down a short hill.  There is a nice tall tree with yellow leaves that works as a good landmark.  Just before it, we find the orange and white flag that signifies each point.  At this point and all of the others there is a puncher that is to be used to punch out a distinctive pattern of dots on a card that each team carries.  This ensures that we actually did make it to the point.

This day is, for me, a series of finding the bearing, spotting a landmark, getting to the landmark, and repeating the process.  To get to Point 2, we continue down the slope until we reach a ravine.  At the bottom, clearly visible, is the second flag.  We all head down to it and get the punch.  Up to this point, our group and another have been neck and neck, but after this point, we break up.  Looking at our map, the shortest path as the crow flies to Point 3 would involve heading straight up the other steep side of the ravine, heading across a flat area, and then down and up a second ravine.  The other group begins this path, but encounters sharp thorns.  We decide to take an alternate route.  We plot on our map a path that will lead us around the second ravine.  Walking out of this ravine on a gradual slope takes us to its edge.  From there, it should be a straight shot to the next point.

Example of one of the flags, this one in the bottom of the ravine.

It seems to be going well.  We are able to avoid the second ravine and are marching in the proper direction when we spot the distinctive orange of a flag.  At this point we make a critical mistake and abandon our path to head straight for it.  At the time, maybe we figured that our bearing was a bit off due to our sidetrack.  More likely, we saw the flag and just assumed it was ours.  We got our punch and were taking our new bearing when our Professor and his course taveling companion walked up to observe.  Our bearing pointed up a tall hill.  We had gotten nearly to the top when I heard shouting coming from the base.  We were going the wrong way, the voice shouted.  We walked back down to our Professor who told us that what we thought was Point 3 was actually Point 7, and if we had continued up that hill we would have gotten way off course.  We thanked him, and, after getting pointed in the proper direction, walked on to our next point.  This error taught us the importance of keeping track of your bearing and pace at all times, and not simply abandoning it when a possible point was in sight. 

The rest of the exercise is largely uneventful.  I regret wearing shorts and a t-shirt, as the undergrowth tore my arms and legs up pretty decently.  Ours was the first group to complete the course.  One thing that I think helped us to do this was in keeping our landmarks close.  That way, it was easy to reach them and take the next bearing; we were able to keep pretty well on the move without a lot of long pauses.

Aerial Mapping

Introduction

For this activity, we used a large inflatable balloon to do some aerial photography and also got a preview of how aerial photography can be done with UAV systems.  

Methods

For the balloon, we inflated it with helium to around five feet in diameter.  When this happened it was let out on a string and a camera was attached to it.  The string was then lot out a great deal more.  When the balloon was about 500 feet up in the air and the camera set to take pictures at a certain interval, we were ready to begin mapping.  We wanted to get a large area for this activity and the best way to do that was to just start walking with the balloon string in hand.  We walked all over the course, starting with a perimeter path and then crossing through the middle.  When we thought that we had covered the right amount of area we returned to our starting location, brought the balloon back down, and deflated it. 

The balloon being inflated.

The camera rig which will be attached with the yellow strings to the balloon string.

The balloon is airborne, with the camera rig attached.

For the UAV, there are many important details to have in mind.  The flight path of the UAV is programmed on computer with Mission Planner software. When setting up the waypoints that the craft is to follow, first create the take-off point.  Next, plot your waypoints on the map.  Finally, make sure to put a "return to home" point so that when the aircraft is done with its route it returns to the point where it took off from.  When it does land, be sure to hit the kill-switch button on the remote.  Failure to do so can be bad if you try to pick up the aircraft and it tries to return to the ground while you are holding it. 

It is important that you do not attempt to run a mission alone.  Two people can run a mission together but three are ideal: a pilot at controls, a pilot in command, and an engineer.  The pilot at controls stands by the laptop computer and monitors the status of everything.  The pilot in command holds the remote, and has manual control over the aircraft.  This task is very important and difficult.  Lastly, the engineer is on hand to fix any problems that arise with the controls or the aircraft.

We were able to see a mission get programmed with the take off point, 11 waypoints, and a return to home point, and then watch it unfold.  There was a camera mounted on the bottom of the aircraft set to take pictures at a set interval, similar to the balloon exercise.

The three-armed UAV, the remote control, and the laptop that were used.

A better view of the laptop running the Mission Planner software.

One of the shots taken by the UAV on its flight.  The resolution is excellent.

Total Station Survey

Introduction

For this exercise we would be learning how to use a TOPCON Total Station.  These are commonly seen being used by highway workers.  They are used to gather elevation data of an area from a fixed point to create a topographic map.  The total station works by sending a laser from the station out to a prism on top of a pole.  This bounces the laser back to the station, where it records the distance between the two as well as the change in elevation between them. 

The TOPCON Total Station, ready for use.

Study Area

The study area we chose is the UWEC campus mall, at the site of the original Davies Center student building.  That building was torn down in recent years and replaced with a large open green lawn crisscrossed with cement walking paths.  It is bordered on its wide sides by a brook and a series of planters in front of the library.  It is bounded on its long sides by the edge of the library and the social sciences building. 

 The main view of our study area, facing the library.

Methods

The procedure is, the total station stays put.  It has a tripod that is mounted into the ground to hold it steady.  Once this is done, the device is calibrated.  Similar to a microscope, it has a rough adjustment knob and fine adjustment knobs.  The purpose of the calibration is to get the device level with the ground.  The rough adjustment gets it roughly in place, and then there are three fine adjustment knobs, one for each leg of the tripod, that need to be dialed into place.  A bevel is above each leg and the bubble in the bevel needs to be centered.  When this is done, the device is ready to use.

There are two additional pieces of equipment that are used to do the survey: the remote, that is used to capture the data, and the pole, which has a prism mounted on top of it.  To do the survey, the pole is walked out to a point in the mappable area and held steady, level with the ground.  The pole has a bevel as well, which makes this simple.  At the same time, a person at the Total Station looks through the viewfinder window and points its crosshairs at the mirror atop the pole.  When this is positioned correctly, he indicates for the person holding the remote to capture a point.  The remote is linked to the Total Station via Bluetooth.  Capturing a point in as simple as pushing a button on the touchscreen of the remote.  After it says that the point has been captured, hyou are ready to move the pole, re-aim the total station, and capture another point. 

Using the Total Station.  Jeremy, pictured in the right, is handling the remote.  Circled in red is the member of our group holding upright the pole.

Points should be taken a reasonable distance from one another.  Obviously, the closer that they are taken, the more precise the resulting survey will be.  For our exercise we took points that were roughly five to ten feet apart.  This generated a reasonable surface for our study area.  With this data in hand, it is easy to import into Arc to generate a elevation surface model.  

The finished Total Station survey, created by group member Travis Haas.