ISR Part 2

We have more exciting news to report from the front line. As some of you may know, CLASlite is a deforestation detection software product developed by a team at the Carnegie Institution for Science at Stanford University. CLASlite uses sub-pixel analysis of Landsat imagery to detect small-scale deforestation such as artisanal gold mining and selective logging. The main limitation of CLASlite is that it is unable to identify the cause of deforestation, only that it is occurring. Thus, we need a system which allows us to classify the mode of deforestation at CLASlite hits and, specifically, to determine if it is natural or anthropogenic. While high-resolution satellite imagery can be used for this purpose, it is cost-prohibitive to obtain on a regular basis. We believe that drones are the perfect tool to address this need by flying to and investigating CLASlite deforestation hits. Today we tested that belief. Here is what we found:

Here you can see one of the mines we located using CLASlite guidance. At the top-center you can see active mining with the open pit, recently felled trees with leaves still on them, and a man operating a water cannon to wash away soil. Directly below that you can see the machine used to remove gold from the sediment and the tailings pile from the processing. At left you can see the pump used to provide the all important water floating atop a raft in a pond formed by an old mine.

It is not hard to fly over the forest here and find mining activity, but the way we found this site is special. We used the most recent CLASlite data, which identified deforestation which took place between June 23rd and August 10th, and used that to target our flights. Using this method we are able to locate new deforestation rapidly and readily identify its source. Here is a visualization of the process:

Red areas indicate deforestation detected by CLASlite in the 6/23/14-8/10/14 period

We then use the CLASlite hits to plan and execute a reconnaissance flight. This is the actual flight path from today.

In addition to the mining shown above, we also found other causes of deforestation. In one case we found agricultural activity and in another we found what appears to be a false CLASlite hit over a stand of young second-growth forest.

Using this method we can augment the impressive power of the CLASlite system by adding the ability to identify the cause of deforestation and provide continual monitoring of that area, if necessary. While our current aircraft has limited range, we intend to acquire larger, longer-range aircraft which can extend this powerful monitoring capability over vast portions of the Madre de Dios region under threat from ever-increasing gold mining activity.

Intelligence, Surveillance, Reconaissance

ISR. That is what our work is focused on here at CICRA. There is heavy gold mining activity in the area around the station and conservation concession and some of it has actually encroached into ACCA property. One of the major missions that drones will conduct here will be patrol to locate new mining activity around the station and the re-occupation of abandoned mines. This monitoring is vitally important to the rapid identification of mining activity so that it can be stopped before it causes too much destruction. This morning, during our first flight here at CICRA, we overflew and mapped old mines that have been closed. This patrol was conducted to see if miners had returned to the mines and reopened them illegally. Here is what we found:

In this photo evidence of active mining can be seen, including mats which the miners sleep on in the center, the machine used to extract gold from the sediments at left, and, we believe, the miners themselves just below the mats in the shade.

This information allows for an almost real time response to new mining activity and allows enforcement to be targeted at active areas without having to spend time patrolling for the mining activity. This is only the beginning of our work here at CICRA but it is a promising indication of what our aircraft will be capable of.

Mother of God

Greetings from the CICRA biological station on the Madre de Dios River. I wanted to take some time to write down what I plan to do over the next 8 days. The overarching goal of my time here is to provide training on the operation of drones (planes, specifically) to the staff here. They will be purchasing an aircraft similar to our Skywalker and will use it to patrol the station’s property. They will be looking for illegal mining encroachment, especially. The training I will provide, while covering the systems in depth on the ground, will also include quite a lot of time flying. We will make the best of the training flights by using them to image some important targets. Those targets include:

• Gold mines (both active and inactive)
• Tree plots
• Uncontacted indigenous populations

While these subjects are varied, they will allow us to answer a number of questions and hopefully provide a foundation on which we can continue to grow the program. Stay tuned to hear more about what we find and what it means. This morning we're off to do our first training flight which will overfly and map the illegal mining activity on ACCA property.

Field notes on airframes

The Ritewing Zephyr 3/Spade. Read on to see why I'm talking about this.

Well, a combination of a lot of travel time and endless challenges has led me to think a lot about the airframe we have chosen for the project. We are currently using the Skywalker 2014 platform with both the 1900 and 1800 mm wings. This is a highly capable and flexible airframe that allows us to carry a large amount of weight, bulky payloads, and fly for in excess of an hour (under the right conditions). There are also other major benefits, such as a tail that is removable for transport. This does make the plane fairly portable, at least much more so than the old Skywalker that did not have this feature. That said, working with the Skywalker extensively in the field has allowed me to observe a number of weaknesses in the aircraft. The major ones are:

• Difficulty in breakdown – The tail is removable but this involves disconnecting servos and any other electronics and antennas which are mounted on the tail, making removal and replacement somewhat time-consuming

• Large size – Even when broken down the plane is large. The wing spar is the longest piece at over 1m long, requiring large transport cases

• Narrow flight envelope – Heavy AUW requires higher airspeed. Unfortunately, as with many large foam planes, the Skywalker has a pretty low VNE. Above about 21-22 m/s we begin to get serious flutter in the wings and tail which can (and has)  ultimately make the aircraft uncontrollable. At a cruise speed of 16-17 m/s, any steep descent (>15°) causes overspeeding. This is problematic, especially in the steep terrain we encounter here in Peru.

• Heavy batteries – A large plane requires large batteries. The plane has no problem carrying this extra weight but carrying a bag full of 6600 mAhr 4S batteries gets old fast

• Moderate durability – The plane is fairly strong but it does not hold up well to repeated rough landings which are, unfortunately, an unavoidable reality of working in places like this

Back in the swing

Well, our return to Villa Carmen could have gone better, at least initially. On flight 1 I got overly ambitious, tried to land in a very small area, and nailed a tree pretty good. That broke a wingtip off, so it was time for repairs. I put the wing back together and found a decent place to fly from, but on our first flight after the repairs I found that the geometry wasn't quite right (it had a strong tendency to roll right. I twisted it back and thought we were ready to go. We put some weight in the nose and sent it up. It still rolled right and the extra weight caused me to stall as I was trying to clear the trees on the right side of the field we were flying from. The stall dropped me a few meters and caused me to clip a wingtip on a tall cecropia, sending me into a spiral that put the plane down nicely right in the top of a tree.

After retrieving the plane (the methods are confidential) I decided that it was worth the risk to use the new style of wings that gave us problems the first time we were here a few weeks ago. I also put on a new tail. So, we were basically flying a new plane.

Yesterday it rained all afternoon, which precluded any test flights, so we finally got around to it this morning. We had 2 excellent test flights where we got all the parameters dialed in just how we wanted them and got the plane flying quite nicely. We decided that the afternoon would be the perfect time for a real mission.

I put together a flight plan to map 380 ha of old growth forest across the river from the station. We sent it out and everything went quite smoothly. The only problem was that there was a ridge I didn't know about, so we had to abort halfway through to avoid flying into it. Even so, we collected imagery of 200 ha and built our confidence quite a bit in the plane we're flying. Tomorrow, assuming the weather is cooperative, we will really get to what we came here for... mapping of one of the last great wildernesses on earth.

Bad news first

I am a little tardy in updating this but when what I'm about describe was happening I didn't feel much like sharing. This post is an update on the past few weeks and my next post will be an update on our progress today (look forward to that one).

In short, things didn't go well at Tres Cruces. We had 2 major problems, which were a diminutive landing area with few visual aids to use while landing and incredibly steep terrain blanketed in very thin air. The first problem is self-explanatory; my success rate in getting the plane on the ground safely was quite low, too low to only be halfway through our field season.

The second problem was really a number of problems. First, the thin air necessitated faster flying to create enough lift. It also made the plane difficult to fly. This difficulty translated to autopilot control, where the APM had a lot of difficulty keeping the plane in line. Finally, acceleration in moderate to steep descents necessitated by the steep terrain were exacerbated by the low drag of the thin air. This meant that while descending it was very easy to overspeed the aircraft. This leads to all sorts of problems, like wing flutter, and causes APM to lose control. On multiple occasions I had to take the plane back into manual to save it from itself.

For these reasons we decided to discontinue flying the plane at Tres Cruces. We have not given up on it, but we are delaying until we can tune the aircraft for high elevation flight and add drag devices to keep everything in check. That probably won't happen this trip, but it will happen at some point.

So, in an effort to remain productive, we returned to Villa Carmen to map areas across the river from the station. This is old-growth forest in relatively steep terrain, but it only ranges from 600-1200m AMSL, which eliminates one of our problems. There are also decent areas to fly from there, eliminating another problem. Finally, the weather here isn't as hostile, meaning we can fly through much more of the day.

So, look forward to updates on our return to Villa Carmen.

Field notes from the top

NOTE: This post was originally written on 7/31/14

Getting the DAO ready to fly in the house at Tres Cruces

Ground control station 3640 m AMSL

As expected, operating drones in a remote, high-elevation area brings with it a significant set of challenges. These range from aircraft performance, to battery charging, to mission planning, and more. That said, one of the major appeals of small-unmanned aircraft is their portability, making them well suited for transportation and operation in remote regions. In this post I will spend a little bit of time discussing the major challenges of operating in a remote, high-elevation locale for an extended period of time.