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I've written my own Ardustation software for talking to the APM using MAVLink. The software is based on my previous version (for APM v1.x), which was in turn based on code written by Michael Smith.

Thanks to Build Your Own Drone for supplying the unit pictured above for testing the compatibility of the software.

So far I have tested it with ArduPlane 2.24. The download is linked below, I've included a previous version in case of difficulties. You will need to use the included libraries.

-- Update 01 Dec 2011 --

Depending on whether you use the airspeed sensor you should change line 50 of ArdustationM.pde such that the PID settings page alters the correct navigation pitch value. Set it to 1 if you are using the pitot tubes

#define AIRSPEEDSENSOR 0

I've found that downloading parameters is currently a bit hit and miss, it seems that only about 10 are downloaded at a time, so you may have to request the parameters more than once before they show up. Alternatively you can edit the local value before syncing with no problems.

Hands-on video over at engadget about this hardware from Rotor Concepts.  Interestingly they cite a max. altitude of 2000 feet...where are they getting their permits??? {-Just a thought}  I'd love to see a hardware breakdown on this.

Compilation of some on-board footage from the my OpenPilot CC Tricopter. This thing is super stable. I have complete confidence when flying with OpenPilot. Can't believe how simple the setup was. I am using 3-bladed props this time. They are much quieter, but produce less thrust. I had to adjust my trottle curve a bit to get better response. All FPV gear is from ReadyMadeRC.

Setup:
OpenPilot CC
AX-2213N motors
Turnigy Plush 18A ESC
GWS 9x5 3-bladed props (2 CCW, 1 CW)
Pro Tricopter Delrin frame
ImmersionRC 500mW 5.8GHz Vtx + Bluebeam SPW
ReadyMadeRC 420XV camera
DragonLink UHF RC System

Hi everyone,

After several weeks of Flying with this plateform it's time for conclusion.

Avantages of OctoV : Payload can be 1 Kg

Autonomie can reach 5 mn with 4S 5000MAh

Against the Wind it flies well

One time the OctoV just fall down from 20 meters (no more juice) but the plateform stay horizontal and the Camera was safe :)  3D camera (really expensive).

I Fly with 2.0.42 ... 10 inch propeller and this stability is perfect.

Can be hard to YAW when the total weight is 4 Kg (YAW PID may need more P ???).

For the construction i use 1 meter Alu (15mm) without any cut :)

I encourage everyone to take the risk of building tha platform, you ll not regret !!! I finally sell it to a movie companie :) makes me sad but technology need to be share to those people. They want to make a movie in Maroco ( they told me about a car race) and for sure they need me to pilot the machine. I FOUND A JOB !!! MUM can be proud now :)

After some decent results described in my previous post regarding PID tuning for high winds: http://www.diydrones.com/profiles/blogs/pid-tuning-for-high-winds, I wanted to see what it would take to get the best possible flight path with the least amount of flight planning possible. The end result was a three waypoint 90degree corner, as shown below.

The problem of course is wind... The above path was with no wind whatsoever, as soon as high winds are added the entire thing falls apart completely, as the plane often missed the last waypoint in the downwind turns and has to circle back.

I figured that if I could get a near perfect flight path with just three waypoints on each corner, what if I went back to using a single waypoint, but simply increased the waypoint radius such that the plane had enough room to make a perfect turn. In theory this should at least be flyable in high winds without having to circle back to hit any of the waypoints...

Unfortunately this failed as well, due to what I think is the Xtrack entry angle, and possibly a bug, or at least odd behavior from my understanding.

It appears that the plane always tries to approach the path at the Xtrack entry angle after a turn, but it also always overshoots the track by a similar angle then has to correct itself. I created the following path by starting with a 90degree Xtrack entry angle at waypoint #2, then cutting that in half for each subsequent waypoint until waypoint #5 where it was 11degrees:

I can understand some overshoot after waypoint #2 (90degree entry angle), and even #3 (45degree), but #4 (22.5degree) makes no sense to me. Its such a shallow angle there should be no problem whatsoever straightening out at the track and following it right on, especially with a Xtrack gain of 225 as shown below, but Ardupilot is still pointing the plane *off* the track (based on the green line) until its well past, then it finally corrects and gets it right.

Can anyone explain why the Xtrack entry angle causes the track overshoot after every waypoint, regardless of how low the entry angle is set? Of course the major problem here is that if there is any wind at all this angle needs to be set sufficiently high enough for it to correct for the wind, otherwise the plane is hopelessly lost. 

Something seems strange to me...

Another good non-military use for drones, reported in Fast Company:

Brazil's environmental police are deploying unmanned aerial vehicles (UAVs), or drones, to monitor the country's vast forest for illegal logging, drug trafficking and other crimes. Named Arara (Parrot) and Tiriba (Little Parrot), the home-grown planes are taking flight to watch over the world's largest remaining rainforest, the Brazilian Amazon

The São Paulo Environmental Police will be the country's first agency to regularly employ (unarmed) UAVs to monitor remote areas for deforestation, illegal fishing, and sand mining. The drones, built by AGX Tecnologia using technology developed at the University of São Paulo, can be deployed almost anywhere, and stay aloft longer than their human-piloted counterparts. AGX’s latest version, with a 10-foot wingspan, can be launched just by throwing it.

From the Google Earth blog, an update of the community-created flight simulator plug-in to GE. Not quite ready for hardware-in-the-loop simulation yet, but it's getting there!

The latest version (.07) includes some nice upgrades:

• 10 aircraft: from the Piper Cub to the A380, through Douglas DC3 and Sukhoi Su-35, helicopters and hot air balloon.
• A map rendering over 30,000 runways to take off from and DAFIF airspace charts (using Google Fusion Table and Google Maps) 
• Real time, local weather conditions (Cloud coverage, wind speed), wind lift on relief.
• In-game chat
• Time slider to select current time of the day.
• Improved physics, animations, flight models, instruments and multiplayer
• Improved user interface, fine control settings, saved preference

This is another great example of why it's so great to build games using the Google Earth Plug-in -- Xavier has certainly made some great enhancements, but there has also been thousands of new 3D buildings (and 3D trees) added to Google Earth in the past year, making it even better!

You can try it for yourself at ge-flightsimulator.com

Inspired by the recently announced APM carrier for the Bixler, I made my own carrier for the Hawk Sky.  Build notes and more photos here:

http://eastbay-rc.blogspot.com/2011/10/apm-carrier-for-hawk-sky-and-related.html

The Cooper Union - Unmanned Development Team

UAVforge.net Entry,

The Aeolis UDMA

Let me know about any improvements you guys can come up with, and vote for it if you like it!

So ... not everyone in R/C hates Team BlackSheep - what a surprise! :) Some even allow us to fly with them. Here's how that turns out:

After a grossly failed attempt at fully automatic landing due to mild winds (luckily no damage), I decided to go back to the simulator and see what PID tuning is required to handle the harshest flyable wind conditions that I could throw at Ardupilot. Because I fly in the mountains and I'm interested in fully automatic take-off and landings, path following needs to be as accurate as possible.

Xplane settings:

Plane: Radio controlled PT60

Weather: Wind: 25kts at 145degrees (from waypoint #3 to #5, never a direct head or tail wind). Shear Speed/Direction 0, Turbulence 0.

Result #1: 

As you can see the air speed (and cruise speed) is around 19m/s and Ardupilot is calculating the wind speed at 12m/s, which should be much higher than you would ever normally fly in.

Result #1 PIDs:

Result #2:

Much higher Nav/Servo P settings, but only marginally better path following, by simply reducing the "bulge" at each waypoint. However as I discuss below, these higher P settings can start to cause major problems.

 Result #2 PIDs:

Result #1 PIDs with no wind whatsoever:

I wanted to find values that still worked relatively well when there is no wind, as you can see they are not too bad but there definitely is some snaking caused by the high Xtrack gain. Lowering this to around 100 reduces the snaking, but virtually kills and high wind path tracking at the same time.

What I've learned:

When dealing with wind, Xtrack Gain and Entry Angle seem to make the biggest difference, increasing P or I values above a no wind situation while can offer minor improvements also introduce a level of risk (at least in the simulator) where in some cases the plane would start rocking and eventually lose control and go into a dive. However increasing the Xtrack gain too much (ie: 1000) often results in high frequency "snaking", because the wind blows the plane slightly off track, Ardupilot over corrects to bring it back onto the track, straightens out, then the wind blows it off track again... Rinse and repeat.

Based on the different forum/blog posts regarding PIDs, they still don't make much sense to me and I haven't been able to get I or D settings to actually help matters, despite hours of tests. :(

The biggest problem with accurate track following appears to be with the fact that Ardupilot doesn't have any turn prediction, so it doesn't start its turn until its right on top of the way point, at which time the wind has already started to blow the plane off track and the PIDs need to be set sufficiently high enough to get it back on track before the next way point. This results in the path "bulges" near each way point where the approach has a tail wind, and "snaking" after way points turning into a headwind, as you saw in the screenshots above.

Does anyone have any suggestions on improving things further? Unless I'm missing something, I would be surprised if anything better than the above paths can be achieved until additional smarts are added to Ardupilot, along the lines of this Turn Prediction.

If anyone wants to give it a try, below are the flight plan and parameter settings that I used:

xplane1_tuning_plan.h

xplane_pt_60_wind.param

Japan's Ministry of Defense released 2 days ago their spherical drone: 350 grams, 8 minutes fly time.

Pretty impressive. Drawing board anyone?

I've been looking around for a cool frame and came across the X650 V4 frame from Xaircraft.

Before I ordered it from BDpowers I did some homework concerning were I would put all the hardware.

The frame has space for the ESC's just next to the motors so I wanted to be certain that my ESC's would fit. I managed to putin them in the tight space but using the X650 ESC covers wasn't possible. Putteing the ESC's under the props keep them very cool. Also the distance between motor and ESC is kept to aminimum. EMI from powerlines will also be reduced this way. I also looked at the center plate that would hold the APM and IMU. It fits nicely and all connectors are accessable. The folding arms of this frame was a bonus.

The current setup are :

KDA 20-22L

APC 10x4.7

Plush 30 A

Motor to motor is 60cm

Currently I'm doing tests with the latest v49 code and the first couple of flight (excl gps and sonar) were very promising.

I would like to upgrade to avroto motors 2814 and perhaps a bigger 11" prop.

Suggestions welcome.

Hey guys,

We have just been setting up and testing a APM with our Scorpion tricopter, Stabilise mode works very well and we have tested loiter with some sucsess, It needs a sonar sensor i think to get a more accurate altitude reading, it is also not very presice on the location, it will drift for quite a few meters. Also while testing auto mode it has a tendancy to lean backwards and slowly drift way. Any ideas?

More testing to come

Here is a video:

Any advice welcome :)

Luke cooke

www.foamzone.de

German and europeen distributor for APM and more

this is a wonderful counter rotating BLDC motor and prop set ideally suited for planes between easystar and skywalker because of small footprint for the power equivalent 30xx size motors. it delivers 270 watts with 3S Lipo. the mounting would be bit tricky though. never tried but would order soon. very useful because prop diameter has to be restricted on pusher prop aircrafts with tail boom below the prop. once i get mine would put the performance parameters on the same blog. available at http://www.rcecho.com/aeo-model-1550kv-contra-rotating-brushless-motor.html

The staff of RCTECH has published a video of the new quadricopter GAUI 500X installed by the navigation system INS GU- HD and GoPro Hero camera. In the video demonstration of the automatic return, the operation of the camera mounted on the frame of the drone and the real-time video transmission with telemetry information on speed, altitude and battery voltage.

GoPro launches HD Hero2 helmet cam, announces video streaming Wi-Fi pack for winter

Check out the full article over on engadget

The wifi backpack may prove to be cool depending on range, but the fact that they are integrating remote control, better streaming ans stills performance really shows they are listening to their customers.  SO, is this YOUR next drone-cam?

This is an airship I designed for the UAVForge competition, it takes advantage of its ability to alter its volume (and thus its density) to take off and land. It is 6 ft long, however folds down into a rucksack.

Some interesting technology I am looking at in terms of software is the Surface From Motion 3D environment estimation

http://ai.stanford.edu/~asaxena/reconstruction3d/

http://phototour.cs.washington.edu/bundler/

and Active Noise Control

http://en.wikipedia.org/wiki/Active_noise_control

Unfortunately I won't be able to enter into the UAVForge competition as I am travelling while their live video milestone is due, but I thought I would post it here anyway if anyone was interested.

My AC2 is assembled, and I was able to do a couple indoor tethered test flights to make sure things are connected and setup properly.  Here is the first test:

This was somewhat of a success for the first flight, in that all of the electronics were basically working correctly, including wireless telemetry.  After re-checking all of the connections to determine why it was immediately pitching over, I found that the 4-wire connector from the APM to the PWB was plugged in backwards.  I switched it around, and re-ran the pre-flight test, paying closer attention to actually which motors were speeding up and slowing down at what time, and tried it again:

It's not immediately trying to pitch over, so I think the stabilization is basically working

A few other things are also going on here:
- There is probably a lot of weird air re-circulation going on in this small area that is causing it drift around, as well as dynamics from reaching the end of the tethers that are making it difficult to stay level.
- Toward the end, it seems to pitch to the back to the right. At this point, even after landing, the attitude showing on the laptop was far from level, I'm sure this is because the magnetometer was not getting a good reading inside, and also because the cords artificially held it at a nonzero pitch attitude without accelerating in that direction.
- I'm using a 20C 2200mah battery, which is too small for this since there are obviously 4 20amp speed controllers.

The next step is to take it outside to eliminate any re-circulation effect, make sure the magnetometer is getting a good reading, and get a GPS lock.  I will probably test it tethered again, maybe with longer tethers -  I think if I position the anchors further apart, the tendency might be to pitch back toward center when it reaches the end instead of pitch away.

YouTube added video stabilization tool to new video editor.

And its super easy to use: Upload your video go to video editor and click "Stabilize".

It will take some time to process the video, but who cares... you can keep using your PC !!!, because all the work is done in the "cloud" :) No more After Effects Rendering :)

And YouTube lets you download your video ( if you didn't used any copyrighted music for it )

I think, that as fully automatic process, it do a very good job !

Here you some samples:

It have only one problem "fish-eye" videos from GoPro HD get a funny distortion :)

But it still looks good :)