Successful test flights

 
Brian Anderson taking the RV Jet for a spin.

Brian Anderson taking the RV Jet for a spin.

After a day of torrential rains -- apparently atypical for Mackenzie country -- we were treated to a beautiful day today that allowed us to complete all of our test flights. We wanted to ensure that the drones could all pass a handful of tests before taking them on the glacier, including (1) a return to launch, aka return to home base, that we would need in case the battery appeared to be running too low to finish the mission; and (2) loitering and dropping in altitude in case a low-flying helicopter was approaching our flying zone. 

We were also interested in range testing the telemetry radio signal strength, and were quite pleased to find that we could fly up to 3km from home base and maintain 99% signal strength. 

Finally, we added the camera into the drone, and surveyed a little over a square kilometer covering the Tasman River valley.

Tom braved the spiky matagouri bush to retrieve the Duck.

Tom braved the spiky matagouri bush to retrieve the Duck.

With all of these tests completed without a hitch (well, almost without a hitch -- as you can see in the pictures, we did have a landing in a very spiky matagouri bush!), we're feeling cautiously optimistic about beginning our surveying of Tasman Glacier tomorrow. The plan is to survey and photograph regions 2km on each side with each flight, moving down glacier (towards its terminus) after each flight. The stakes will be a little higher, as it will not be easy to retrieve the drone if it happens to crash land on the glacier, but all the tests we performed today indicate that we should be able to stay in the air without a problem.

Karen launching the Sky Hunter with Tom at the controls. Kevlar gloves offer hand protection, just in case there is any unfortunate propellor-hand contact. 

Karen launching the Sky Hunter with Tom at the controls. Kevlar gloves offer hand protection, just in case there is any unfortunate propellor-hand contact. 

Now, it's time to get our computers crunching on the DEM of the glacial valley from our test flight today, and we're off to the glacier tomorrow!

Can you spot the Duck?

Can you spot the Duck?


 

The drones have landed -- in New Zealand

 
Our vehicles in the background after arriving at our launch test site.

Our vehicles in the background after arriving at our launch test site.

We've already had two successful days in New Zealand prepping for the campaign. Despite the impending threat of a tropical cyclone, the weather yesterday was mild enough to do some test launches and flights in the glacial outwash plain. Not a bad place to fly drones, we think:

Tom McKinnon (foreground) and Brian Anderson (background) put together their drones for the test flight.

Tom McKinnon (foreground) and Brian Anderson (background) put together their drones for the test flight.

Today, we went up to Tasman Glacier to scope out potential launch and landing
locations. We plan to obtain imagery to make a DEM that spans with width of the glacier,
about 2km, and extend from its terminus to 6-7 km upglacier. Tasman Glacier terminates
in a large lake, as can be seen in the picture below, which presented an intimidating 
first domain for flying. Luckily, we found a few nice* places to take off and land as we moved
farther upglacier, so we don't have to tackle flying over the lake until later in the campaign.

The terminus of Tasman Glacier.

The terminus of Tasman Glacier.

The forecast is not particularly encouraging with respect to winds for the next few days,
but we are hoping to do a long-range test flight tomorrow, and then try our first over-glacier
drone flight in the next couple days. Once we have the first set of photos, we can begin to 
process them into our first Tasman DEM. More details to come about how the full process --
from drone to DEM -- works. 

*as in, not covered with giant boulders

 

Dispatch from SFO

 

The Agribotix glacier monitoring team is en route to New Zealand for a field campaign that is cooler -- literally -- than agricultural monitoring. Upon arriving in Christchurch on Saturday morning, we'll be heading straight to Tasman Glacier with two drones and a few cameras in tow. There, we'll spend up to two weeks creating a digital elevation model, or DEM, of the lower 10-15km of the glacier from aerial photography. The goal of the project, planned and executed in conjunction with Brian Anderson at Victoria University of Wellington, is to prototype a method for producing accurate yet affordable DEMs of mountain glaciers.

Tasman Glacier. Photo courtesy of Andrew Mackintosh. 

Tasman Glacier. Photo courtesy of Andrew Mackintosh. 

Mountain glaciers tend to be sensitive indicators of climatic change, but they are often under-monitored, so it can be hard to say just how much their area and volume have changed in the recent past. Unlike ice sheets, their scale is small compared to the scale of satellite measurements, and there simply are not many resources to support on-the-ground measurements. Smaller-scale aerial surveys have primarily been done by helicopter or plane, and can be too expensive to perform regularly.

Drone surveys have the advantage of providing the aerial perspective without the costs associated with helicopters or planes, so could be performed on a regular basis. The change in the elevation and extent of the glacier -- quantified with the DEMs -- with respect to time can be translated into changes in the glacier volume.* This dataset has the potential to provide a large amount of new information about the sensitivity of mountain glaciers to changes in the climate.

Stay tuned for more updates as the campaign begins!

*This assumes that the glacier bed (where the bottom of the glacier meets the earth surface) is not changing its shape or elevation, which is probably a safe assumption on decadal to centennial timescales, but not necessarily on very long ones!