Field Navigation: GPS and Paintball

Introduction

Using a GPS has become part of the mainstream in the world of navigation. This exercise was similar to the previous weeks exercise, but now the groups were using GPS units instead of  maps and compasses. The Priory was again the area of navigation. Another added bonus to this exercise was the implementation of paintball markers.

Methods

Before this navigation exercise the groups had to recreate the navigation maps of the previous exercise. The maps had some added features this time. The most notable of the additions was a path of travel. Each group seemed to have a path of travel to each point. This was also something new. Every group had to go to every point instead of a few selected points, but the starting points were different. Each group determined their own path and went with it. The maps that were created in ArcMap were imported into a Juno Trimble GPS and were used in the mobile Arc variant that is ArcPad.  The group moved along the path to each point.

Figure 1: Me, Eric Fabian, checking if the paintball marker is ready for use

 Navigation

Our group had point 10 as our starting point. This point was on the opposite side of the Priory and our group made quite a trek to the starting point. The GPS points were exactly where they were supposed to be. The route of travel went through the very wooded area and travel was quite treacherous. For added protection we had our paintball markers. It was not until our second point that we met another group and had to open fire. I believe that the group already had their point and retreated. The point were still difficult to find as moving with the GPS can still be tricky to read.

Figure 2: The groups map and points. One can see that the points are a bit off but that is due to numerous reasons.

Discussion

Added paintball markers was a fun addition. The GPS unit to me was still a bit difficult to read and navigating through the woods was still the same as the previous week. I think that compared to one another the GPS may be only slightly more helpful but a map and a compass definitely fulfills the need of travel.

Conclusion

Using a GPS to navigate has become the mainstay of today. GPS points can be accurately found in a timely manner as long as navigated correctly. The area to me plays the most on navigation. Being able to have this skill and being able to teach it also helps.

First Navigation Map and Compass

Introduction

This weeks exercise was the fulfillment and use of the navigation maps that were made in exercise 5. The class went to the Priory and were tasked to use a map and compass to find points around the Priory. Once the point was located the group used a punch card to mark that they had been there.

This navigation exercise helps one understand that technology will not always be readily available. To be able to use a map and a compass is a reliable skill.

Study Area/Course

The Priory is a large plot of land, roughly 112 acres, that was purchased by UW-Eau Claire in October 2011. The facility is used to house students, hold a daycare, and be used for educational purposes. The land is mostly wooded and this is where our group navigated. Each group had a separate area to navigate.

Methods

Figure 1: Morgan pointing towards an area that could be the direction of a point

The class was divided into 6 groups of 3 members. Each group had to use 2 maps chosen by the group. These maps were created for exercise 5. Group 3 had area 3 which were points 11-15. The starting point for the group was a gazebo on the back side of the Priory facility. The group received multiple maps and had to plot the points using reference grids that were on the map. Two sets of coordinates were given for each point. The coordinates were in both UTM and decimal degrees. Once the points were plotted the group used the compass and a map to go towards the direction of the point. The method of finding a point includes plotting line of direction and then using the compass to find north on the map. Once north is found turn the compass to find the degree of the point. This is called the azimuth, the direction of the point and travel. If a point is at the 280 degree mark place the arrow so that it is red in the shed. Keep the arrow in the degree area to find the point. To find the distance one uses a scale bar from a map.

Figure 2: One of the maps used for navigation

Figure 3: Lee quite pleased with finding one of the markers

Discussion

This method of finding direction was difficult at first to say the least. At first the group could not find the flag and accidentally stumbled upon flag 14. This flag was one of the points that needed to be found. The group decided that working backwards was the best option since the group was so close to the final flag at 15. The hardest part of the exercise was simple miscalculations. These simple problems caused the group to be far enough away from the flags not to find them

Conclusion

Using a map and compass seems archaic, but this exercise showed that it is a useful tool. Using these methods can be very beneficial.

Aerial Mapping With UAS I and II

Introduction

Aerial imagery can be processed and used in many different ways for many different reasons. The broader view and different vantage points of aerial imagery are huge benefits for many different reasons. Equipment that utilizes aerial imagery can be in the form of a balloon, kite, UAS, or rocket. The class used to of the former ways, the UAS and balloon, to view and process aerial imagery. Many preparations go into aerial imagery including using cameras, GPSs and other technical equipment. The class got to go outside and test the equipment at the Eau Claire Soccer Fields. This blog is two-fold. The first part is focused on image taking, processing, and the mosaic method. While the second half is a UAS mission pre-planning and flight.

Study Area

The Eau Claire Soccer Fields are located approximately 1 mile south of UW-EC campus. The fields are a large open area near residential housing and the Eau Claire Indoor Sports Center. The openness of this area allows for great flying. The area was suitable for the balloon because it had a great range of motion and could fly very high (500 ft). This ability to fly high allowed for a larger area to be captured. For the UAS the openness of the area allowed for easy maneuvering and easily accessible control points.  

Methods

The balloon was a simple large rubber helium balloon attached to a string with a picavet rig. The picavet rig is attached to the string and is where the camera and GPS are attached. Two cameras were attached to the picavet rig, these were a Canon Sx260 and a Canon Elf. The reason for 2 cameras is to get as many shots as possible and see the difference that multiple mediums take in the same area. The GPS was attached to know where the location was for the future process of mosaicing. Once all the equipment was set up the balloon was then lifted into the air at preplanned height of 500 feet. The class then walked around the field to capture multiple images. The route that the class walked was made to utilize the largest area so that many images could be captured. The route was made for minimal overlap, but some overlap is good. Hundreds of images were collected for mosaicing.

After the fieldwork was all done image mosaicing had to take place. Image mosaicing is basically stitching images together to make one large image. This is where hundreds of images come in handy as well as overlapping of images.

Figure 1: The balloon before take off. This shows a size reference for the balloon.

Figure 2: The two cameras and the GPS mounted on the picavet rig

Figure 3: The balloon ascending into the air

PhotoScan

To create mosaiced images in Photoscan add the photos you want under the Workflow tab. After adding the photos go back to Workflow and select Align Photos. This alignment of photos creates Point Cloud which are points of the photos. After the alignment select Build Mesh from Workflow. The mesh will create a TIN which is a Triangular Integrated Network. This means that triangles are created from points to create pieces of an image. In tabs click Texture. To export the image to use in other program click Export Orthophoto. The best option is to save it as a TIFF. After the TIFF is saved and exported open ArcMap. This step is needed only if the image is not geotagged. To geotag the image open Geoprocessing. Open an image of Eau Claire that has been geotagged. Click Viewer which is the magnifying glass this opens a spate view with the area that is not georeferenced. Adding control points to the image will help geotag. To get the track log another software program is used. This is Geosetter. Geosetter will help create GPS points and rectify the image.

Figure 4: An image mosaiced together in Photoscan. As one can see the area is quite large

Figure 5: Another mosaiced image from Photoscan

UAS Methods

There are many pre-planning methods that go into UAS use. If any step is missed the whole operation could be a mess. Tests should be ran before the UAS start up.  This includes waiting for a GPS connection and a connection between the UAS and software that is used to fly. The software the Professor Joe Hupy uses is Mission Planner. Mission Planner is freeware that can be used by anyone. Connection to Mission Planner from the UAS is signified by a green light on the software. No less than 3 people should run a UAS mission. The 3 members ideally should be a pilot who manually controls the UAS, a pilot at the computer, and an engineer that knows all the software. One should first know the topography of the land before flying as to best map out a flight plan.

Figure 6: Professor Hupy using the Mission Planner software prior to UAS launch

For Mission Planner there is a grid of points. These points are referred to as waypoints and are number in sequence. The first point is home and the UAS will return home when it has hit all the points. If the UAS is at 60% and is not close to home the pilot should force the UAS to go home. Once the UAS lands the pilot disarms the UAS and makes sure that everything is off. Professor Hupy’s Y6 rotocopter has a flight time of roughly 15-20 minutes. The area that was chosen had a flight plan less than that so no issues arose.

Figure 7: Professor Hupy's Y6 rotocopter prior to flight. Next to the copter is the controller

Discussion

UAS and other alternative aerial imagery processes have many positives and UAS definitely looks to be the future of aerial imagery and remote sensing. With UAS the cost is cut down and the areas acan be explored more broadly. The alternative of UAS is a booming industry and can be used for anything from police work to agriculture.

Conclusion

UAS removes the human element and allows for a more expansive area of work. The camera does not have to be that advanced on any form of aerial imagery but to think of the future of camera resolution it is amazing. UAS work is more expansive than the current alternatives of balloons, kites, and rockets. The future is very bright with these advancements.