Apr 04 2012

Hexakopter Flying and Testing the GoPro

Stephen and I practed flying the hexakoptors.  We were able to fly Roflkopter (one of the hexakopters) from the lab to the library, over the library and adjacent garage, and land on a 2ft by 2ft board.  In addition to the lirary expedition, we also practiced maneuvering the hexakopters, landing on a target, and getting them flying at the correct altitude.  Furthermore, we used the GoPro camera to capture video and pictures of the flights.  (The camera was mounted on the hexakopter.)  Unfortunately, the pictures had a lot of compression (as can be seen by the picture to the left that was taken in the lab).  Next week we will be testing to see if adjusting the setting will yield better images.

Below is a link to a video from the GoPro as we flew through Academic Row.  The first half of the video is with the distortion and the second half is the cleaned-up version.

http://www.youtube.com/watch?v=YtPkQShCR8c&context=C451b577ADvjVQa1PpcFNA2j44Y1Kwcn_6Rdo149XVXfaZn7cl70E=

 

 

Mar 20 2012

New Jersey Pinelands Fire Research Flight

This past Tuesday (3/6/12) Jonathan and I travelled to New Jersey to conduct wildfire research.

We left Monday evening and drove to the New Jersey Pinelands, where we stayed overnight at the research center.  Our first obstacle was the smoke research payload.  When Jonathan did this smoke research in the past, he had suspended the payload (consisting chiefly of a smoke detector and data logger) on a tether beneath the hexakopter.  The reasoning behind this was that we needed to keep the payload well away from the air disturbance made by the hexa's propellers.  However, the problem with this method is that the hexakopter is unable to self stabilize under a suspended payload, and ends up swinging the payload wildly and eventually crashing.

Jonathan and I did a brief test to confirm that this behavior was still present with the fire payload, it was.  As a solution, we mounted the payload on top of the hexakopter's dome.  A strip of ribbon attached to the top of the payload served to demonstrate that the propellers did not significantly interfere with the airflow though the payload when it was mounted on top.  The hexakopter was perfectly stable with the top mounted payload. 

Tuesday during the wildfire we flew from the research compound which was downwind of the wildfire in the smoke plume.  The hexakopter flew up in 50 meter increments and back down every half hour or so for several hours.  Overall our data collection was a success.  Towards the end we even had the time to mount a camera on top of the payload to take a rather jittery video of the wildfire from the air.

Mar 16 2012

Updates: Hexakopters, Quad Arducopter and Octocopter.

Now that the hexakopters are basically complete (one has a programming error that we are currently working on), Stephen and I decided to work with our other projects: quad arducopter and octocopter.

The quad arducopter (4 blades) is working.  We spent a few days familiarizing ourselves with the parts of the copter using the arducopter wiki (http://code.google.com/p/arducopter/wiki/ArduCopter).  The electronic speed controller (ECS) still needs to be calibrated, but it the copter is connecting to the computer and seems to be in working order.  We have started the parts list so that we can move forward.

The octocopter (8 blades) is still in the supply obtaining phase.  We have already placed our order for the necessary parts to construct the copter.  Within a few weeks we shall have those supplies and can commence the construction!  The objective of the octocopter is to run the trials the hexakopters are currently doing, but more efficiently.  It is also hoped that we can use the octocopters to expand the scanning area. 

Feb 27 2012

SERC Leaf-off Hexakopter Mission

This past Sunday (2/26/2012) Jonathan, Shelby, and I went to the Smithsonian Environmental Research Center to fly a hexakopter mission during leaf-off.  The image on the left was taken by the camera mounted to "Sally" as it was coming in for a landing.

Since "Raven" still has what we believe is a motor controller issue (contacting Nisarg about this), we brought "Roflkopter and "Sally" to SERC.  Initially "Roflkopter" was designated the primary flight hexakopter, because "Sally" had been noticed as having stripped threads on one of the propeller mounts on top of a motor.  Since the other two holes in the propeller mount were not stripped, we still considered "Sally" flightworthy, just not primary.

Once on site, Shelby and I set up a series of twelve orange contractor buckets along the road through the forest we were surveying.  Jonathan had programmed the rough distribution of them into the dog-tracker GPS to follow when we were setting them out.  Then throughout the rest of the day during flights and other work, we used a handheld GPS tool to determine the precise coordinates of each bucket.  These coordinates will be applied to the buckets in the point cloud representation.

As it turned out, "Roflkopter" was not our best choice for primary hexakopter.  Although it was certainly flightworthy, during flight it bobbed up and down instead of flying in a straight line.  Jonathan believes it is due to the hexakopter's vertical lock setting being miscalibrated or otherwise dysfunctional. 

We decided to fly "Sally" to see if we could collect data from a smooth flight.  After some test flights, we determined that the stripped screw on "Sally's" propeller mount was not going to be an issue this mission, although it will still be replaced.  On "Sally's" first mission, everything seemed to go well but when it returned the camera had run out of battery.  This was odd since the battery we used was most definitely fresh.  The camera did not seem to respond well to new batteries either, so we flagged it for later investigation and switched to a new camera.  Finally, "Sally" flew a successful flight and collected what looks like it will be a complete set of pictures of the forest canopy.

Jul 29 2011

Introducing "Vanga"

I work for REBIOMA - a joint project of UC Berkeley's Kremen Lab and the Wildlife Conservation Society, Madagascar. We develop and apply spatial tools for biodiversity conservation in Madagascar. For example, we work with a wide array of individuals and institutions to publish high-quality biodiversity occurrence data and species distribution models on our data portal - work that has helped to identify 4 million hectares of new protected areas.

Last week, I visited the Ecosynth team to build and practice flying what we're calling "Vanga" - a Hexacopter that we will take to Madagascar in late 2011 to map forest cover and forest disturbance in the Makira and Masoala protected areas. 

We're excited about the potential for low-cost, high-frequency forest monitoring in two and three dimensions. We will start by testing the capacity of the system for producing high-resolution 2D ortho-mosaics of selected field sites. We also hope to explore the 3D modeling capabilities - this has real potential for contributing to ongoing biomass measurements, and contributing to forest carbon inventories. Finally, we plan to evaluate the potential of this system as a tool to help communities adjacent to protected areas measure and monitor their forest resources.

Jul 29 2011

Multirotors on the Colbert Report

colbert_quadCheck out multirotors on the Colbert Report!!!  The clip starts at about 15 minutes into the program.

The researcher, Missy Cummings Associate Professor from MIT, is developing better human multirotor interfaces to help people steer the units using only a smart phone, which makes me wonder how different it is from the Parrot AR.Drone.

 

http://www.colbertnation.com/full-episodes/wed-july-27-2011-missy-cummings

Seeing this video reminded me of something I noticed when flying the Hexakopters on campus with Tom Allnutt last week, see his post here.  Many people stopped and asked, ‘What is that?’, as usual, while we were out practicing in the Quad at UMBC.  But almost everyone asked if we had put a camera on it, as if that was the obvious thing to do with such a cool device.  I explained to them our research and that we do usually fly with cameras and thought to myself that something is different now then when we were practicing last year.  In September 2010 when people asked us what we were doing they never asked if we were putting cameras on the devices and thought it was an odd thing to do when we told them about our work.  Now it seems that the practice is even expected.  I hope this signals a shift in perception about autonomous vehicles as useful tools for research and for recreational aerial photography and not just greater public awareness about the other uses of such devices.

UPDATE: I've been thinking about this post and in all fairness, the researcher is discussing the use of multirotors by the armed forces.  I posted for the sake of noting the signifcance of the devices in pop-culture.

Oct 19 2010

3D and Spectral Remote Sensing with Computer Vision

Wow, what amazing progress!  I posted a few weeks ago when we were just starting to get the Hexakopters working, how excited I was when I considered that we were still flying kites just ONE YEAR AGO!  Now it is becoming a reality that the Mikrokopters can really move this interdisciplinary research fusion of ecological remote sensing and computer vision into a reliable system for making 3D, spectral color measurements of ecosystem vegetation for measuring biomass and species diversity.  

There is definitely a lot to learn about the process, but we have got the flying down pretty well for data collection.  The video here is of me flying the Hexa up through a large gap in the canopy at the Knoll site at UMBC.  This is an invaluable capability of this system (and its pilot!) that makes it possible to fly sites like the Knoll and SERC, where it is not possible to be centrally located in a large open clearing.  

DRAFT: comparison at HR sites, seasons

Oct 07 2010

Back in the air and doing great!

mobile_command

One week after a nasty crash at one of our suburban forest study sites, we are back in the air and *hopefully* back on track for a great collection of vegetation dynamics this month.

More on the crash and the rebuild on the Weekly are forthcoming, the team has mid-terms right now, but I wanted to post about the recovery and success today.  We had two Hexas on order and they arrived on Thursday of last week.  Nisarg and Garrett put in the time this past weekend to get the two new birds up and running and we had a few great tests in a parking garage and in an empty gymnasium, inside because of a cold autumn rain.

On Monday we calibrated the receivers to the units and everything appeared ready for great flights once the weather broke.  The forecast called for rain until Thursday and then becoming beautiful.  The forecast for today included rain but the morning and midday had light winds and mostly overcast skies so we decided to go for it.  I knew the gear was ready and I pulled out some of my new pre-flight checklists to prepare the field kit.  Garrett showed up and helped with the packing while I prepped the official flight path in ArcGIS.

Here is the breakdown of field work by time:

  • 10:30 – Arrive at site and unload (leave note on car begging not to be ticketed)
  • 11:30 – All markers are placed with position recorded in GPS
  • 12:00 – Back to site and ready to go after realizing I left camera battery in lab
  • 12:05 – Garrett has arrived and we are powering up Hexa
  • 12:30 – Updated and verified Mikrotool settings, unit has GPS lock, ready to go…
  • 12:33 – Take off!
  • 12:48 – Jonathan grabs Hexa as it makes its descent. Touchdown.
  • 13:05 – Gear is packed up; Depart site
  • 13:30 – All gear has been unloaded and we are back in lab downloading data

In sum, about 2 hours on-site for what appears to be a perfect 15 minute data acquisition.  I expect that we can take off at least one hour from this as we get better at making acquisitions.  A Photosynth of the photos is running now and I will update with a link when it is ready.  I have also attached below the KML file of the track downloaded from the MicroSD card on board the Hexa’s navigation control board.

HR_20101006_Mikrokopter_GPS_telemetry.KML (49.45 kb)

UPDATE: The Photosynth run is finished, http://photosynth.net/view.aspx?cid=011796ed-ed9e-43d5-bc0a-f5a80bcae7d6 . This was based off of every other photo in the set, amazing.  I can't wait to get some seasonal change in the canopy, it will look beautiful.

 

Sep 20 2010

The Mikrokopter Lives!

kite_mikro_evolve My, how far we’ve come! 

Just about one year ago I was out flying my kite almost everyday to get coverage over our two study sites on the UMBC campus.  Over this past week we have made a huge step forward, a systematic ‘test’ flight with the Mikrokopter Hexacopter over the Herbert Run forests.

Flying the large delta conyne kites (like the one shown here, image credit Into The Wind Kites http://www.intothewind.com/) was fun and got the camera in the air, but it was very hard to control both the altitude of the camera and its position over the forest.  This meant it was very difficult to test flight plans, or even begin to get at understanding the best flight plan strategy for use with computer vision.

Over the past summer we worked with several students from the UMBC GES and MECHE departments and a visiting intern from Clark University (thanks Evan, Nisarg, Garrett, and Noam) with the goal of using hobbyist aircraft to carry the cameras.  We moved away from using the Canon CHDK camera setup, instead using high-speed (~2 photos / sec) cameras with continuous shooting modes to collect huge numbers of overlapping photos.  We had a lot of promising flights and successes with the hobbyist aircraft, the Slow Sticks and Easy Stars.  But we also had a lot of technical challenges and crashes that made us question the sustainability and repeatability of the ultra-cheap systems for our scientific research and technological development stage.

Enter the Mikrokopter Hexacopter.  The Mikrokopter line of remote controlled aircraft offers precision control and GPS navigation.  Last Friday we made our first demonstration of the GPS-assisted navigation over the Herbert Run site.  The Photosynth generated from those photos is here, http://bit.ly/bqAhzL, and while it looks similar to the rest of our aerial synths, it is generated with photos taken along a pre-designated path at a constant altitude.  Remarkable!

I expect things to progress quickly this fall (that dissertation is calling) and we have set up another blog for weekly progress about the nitty-gritty of Ecosynth research, http://ecotope.org/ecosynth/blog/.  I will continue working with this blog as a reference for the methods and research progress and the ‘weekly’ should be a place to go for latest in weekly goings-on in the Ecosynth lab.

Thanks team, we could not have gotten here without all of your hard work.