Geospatial Field Methods: Activity 3: Equipment Construction & Testing

Introduction
This activity was a prep session for the activity that we will be doing next week. The class plans to use a balloon rig to take aerial photos of the campus. We will also be conducting a high altitude balloon launch (HABL), with a camera rigged to it. During this activity, we simply needed to construct the rigs for both, and test all the equipment to ensure that the launching of the balloons is smooth and successful. The class was not split in to groups for this activity so it was somewhat unorganized, but I mostly helped with the construction of one of the balloon mapping rigs.

Methods
As said before, this activity was a prep for the next. There were several different things that needed to be prepared and tested during this activity. The list consisted of construction of a mapping rig, construction of the HABL rig, parachute testing, payload weight, testing the continuous shot on the cameras, and testing of the tracking device. I mostly helped out with the construction of one of the mapping rigs (two designs were created) so this methodology will consist of the process of the mapping rigs construction.

Our design for the mapping rig included the use of a one gallon Rain X bottle, a camera, string, tape, and scissors. The main idea was to mount a downward facing camera inside the Rain X bottle with the bottom removed. The first step of this process was of course removing the bottom of the Rain X bottle. It was necessary to leave enough length for the camera to hang, and have a length below the camera so that when the rig lands, the camera isn't damaged.

Figure 1: The rigs plastic bottle casing.

Once we finished the rig's casing, we had to come up with a design to hang the camera inside of it. Our design calls for 1.5 meters of string that is tied into a loop. Two ends of this loop are then wrapped around the camera, securing the string to the camera with tape. The length of the string that isn't secured to the camera is then pulled through the bottom of the casing and out the nozzle on the top of the bottle. The string would then be attached to the balloon. In order to keep the camera hanging freely within the case, and not pulled to the top by the balloon, another length of string was attached to the camera, pulled out the top of the casing, and then tied securely to notch at the bottom of the plastic bottle casing. Figures 2 through 5 show the camera rigging in detail.

Figure 2: Rigging the camera.

Figure 3: A look at the camera's face.

Figure 4: The camera as it hangs.

Figure 5: The camera within the casing (note the additional
rigging on the bottom of the casing).

The final touch to the rig are the stabilizing wings on the handle of the plastic bottle. These were made by cutting a six inch section off of the side of a 2 liter pop bottle. The wings were then securely taped to the rig's casing. These wings are necessary to stabilize the rig, and reduce spin from wind when the rig is in the air. With less spin, we would be able to collect more consistent images, and make it easier to mosaic when we make the aerial map in our next activity. Figure 6 shows this final step.

Figure 6: The rig's casing with attached wings.

Discussion

I thought that this activity went pretty well, even though it was a bit unorganized. The rig that we worked on did turn out well, but it seemed to me like the work wasn't evenly spread out. It would've helped if we had been divided into groups again, and assigned what to work on so that each person had something to work on.

Results

The overall results of this activity were quite well. The class completed everything on the list that needed to be prepared and tested, including two different balloon mapping rigs, a HABL rig, parachute testing, camera testing, and equipment weighing. We now have nearly everything ready to begin the next activity (everything except the balloon prep, which would of course need to wait until the launch day anyway). Figures 7 through 10 show projects that other students worked on and completed with this activity.