If At First You Don’t Succeed – Field Day 04.23.15

Gearing up for a field day
Kite? Check. Helium? Check. It takes quite a bit of gear to execute a proper field day. Professor Jason Pittman arranged a KAP/BAP field day, and we headed up to the wetlands on the north end of campus to meet students around noon. Following a brief safety talk and protocol orientation, one team set out to launch the balloon, while the other team assembled and attempted to launch the kite.

Filling balloon Number 1
Half-full, balloon #1 revealed some pinhole leaks, so we tried to move the gas to a second balloon, which didn’t work at all, and we popped the first one in the process. Fortunately, we were able to get one of the spares filled and in the air.

The kite team struggled with inconsistent wind. After many heroic attempts, they eventually scrapped the launch and joined the balloon team to walk the wetlands.

We flew for ~40 minutes, with the camera (iPhone on the picavet, running Timelapse at 10 second intervals), and captured some really good shots.  (Link:  The full set images from 04.24.15 BAP field day.)

At 2 o’clock, we headed back to the cars to stow the gear and head out. A few students hung around and had a chance to fly our newest quad.

All things considered, a successful field day.

3D Printing a GoPro Lens Cap

We got some new GoPro Hero 4 cameras for the project, and as usual, the cameras don’t include a lens cap.  Downloaded one from Thingiverse and printed out a few.  Still working out some printing issues, but they printed well enough, and fit perfectly.

GoPro Lens Caps

(CC BY-NC by Thingiverse user PrintTo3D – http://www.thingiverse.com/thing:13276)

iPhone/GoPro Mount Mashup

iPhone/GoPro Mount Mashup
We’ve had some success using the iPhone for aerial imaging from kites, balloons, and quads, so I’ve been looking for a way to mount one to our new Phantom’s GoPro mounting base plate. A quick search of http://thingiverse.com returned this GoPro-compatible iPhone case created by N3W0NE (CC BY-NC-SA). I printed it out on our new Printrbot, and while it technically fits, it needs a little adjustment to be ideal for our situation.  Most GoPro and iPhone users want to mount cameras facing forward, but ours needs to be pointing straight down, which sometimes doesn’t quite work – various mounts and housings get in the way.  For this model to work correctly for our needs, it needs to be tweaked so that the GoPro mount bit is on the short edge of the iPhone.  Not a big deal, and I’m grateful that communities like Thingiverse exist, and that folks are willing to share their work.


Before and After

Thanks to the very responsive team at Publiclab.org – Stewart, Jeff and Liz! –  MapKnitter is back up and running exports.  Here’s a before and after version of one student’s work with the balloon photos:

Before and After
Overall, a fine result, but a few anomalies might bear some experimentation.  For instance, the dropouts toward the top of the north/south path on the left-hand side, and a small faded out area near the bottom left, just above where the east/west and north/south paths join.  If I had to guess, I’d say these were the result of too many overlapping images in those particular sections.  I think I’ll see about thinning out some of the overlaps to see if I can’t get a cleaner export.

Update – Preliminary MapKnitter Output

Here’s a screenshot of one of the many photo composites that students are working on with the data gathered from the balloon flight a couple of weeks ago:
Preliminary MapKnitter Output
MapKnitter is being finicky about exports, but hopefully that will resolve itself before long, and students will be able to get their hands on the stitched photos for further analysis.

Field Day!

November 3, 2014.  Clear and cool with a light breeze – a perfect morning for field work.  Students from Professor Pittman’s GEOG 331 – Exploring Maps and Geographic Technologies course gathered in the parking lot at the north end of campus for some balloon aerial photography.  Jason explained some of the basics and gave a safety orientation.  Rule #1:  Anyone handling the line must glove up!


As we filled the balloon, we realized that we had miscalculated the helium required.  The tank wasn’t quite full, and the balloon wouldn’t pull the picavet with the Canon SX130.  Forced to improvise, we clipped a much lighter iPhone rig (running the TimeLapse app) directly to the string attachment point, and we were ready to fly.

Explaining the Picavet

With the lighter camera setup, the balloon flew fine, and students walked the trails that run through the wetlands.

We uploaded the photos to Google Drive, and over the next week, students will use Map Knitter to stitch the photos together and georeference them.

Fall Colors from Overhead

Streaming Balloon Video

For Folsom Lake College’s 10th anniversary celebration, we rigged up the balloon to stream video to a monitor on the ground, using a custom rig with a POV camera, battery, and transmitter, all housed in an apple juice bottle rig.

Apple Juice Bottle Streaming Video Rig

Never having tried the setup before, we launched the balloon, and streamed the video to a little field monitor.  Everything worked perfectly, and on the first try besides!  Children seemed to appreciate the balloon’s eye view of the college.


We had to pull the balloon down and hide it from the falcons that were flown once or twice throughout the day.  Apparently balloons are used in training the birds, and we were concerned that they would go after it.


After the falcons had finished their flights, we launched the balloon again, now streaming to a much bigger monitor stationed at our table. Once again, things worked exactly as planned.  The video was surprisingly clear and the stream stable, save a few transmission hiccups from time to time.


Next steps include building a dual rig, with a camera for still images, and the streaming gear to aid in positioning the balloon. We also need to explore fins or other means of stabilizing the streaming rig, as it got to swinging pretty severely at times. It was attached directly to the string attachment point, so it’s entirely possible that hanging it from a picavet will take care of the swing.

First Balloon Flight


With the easing of the helium shortage, we finally acquired a tank or two of the noble gas, and headed up to the El Dorado Center yesterday to launch our new imaging platform. First flights are always a little nerve-wracking, with safety considerations and weather variables and unknowns, but we drafted a protocol, filled the balloon, and sent it up.


We had used half the tank the other day on an aborted attempt – the balloon popped – so we ran out of gas a little short of the balloon’s capacity.  While it lifted the picavet, it wasn’t especially enthusiastic about it. We brought it back to the ground, changed the 300# line to 100#, removed the bucket, and sent it back up. These weight tweaks worked well, and the balloon pulled the load gently but definitively.

Release the picavet!

A balloon is quite a different animal than a kite, and flying it took some getting used to. All in all, quite a bit less stressful than kites or quadcopters, as the helium counteracts (most of) the drop-out-of-the-sky, camera crushing effects of gravity. We were able to capture this nice image of the El Dorado County Master Gardeners Demonstration Garden, a work in progress, and one that we can hopefully document over time with additional flights.

Demo Garden from the Air

Overall, a satisfying success.  Next steps include constructing a new, lighter picavet specifically for the balloon, and finalizing the POV streaming rig we plan to fly over the crowd at a college event in October.