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I will be competing in the Sparkfun AVC competition this year using Ardupilot hardware in a ground vehicle. My car is called Minuteman, and works on simple dead reckoning. It uses Ardupilot hardware, with an optical encoder and a gyro as the only sensors. No GPS, no compass, no proximity sensors. Testing has been really simplified by using the ardupilot, because with my 3 channel radio, I can easily switch between auto and manual mode with the push of a button. I can first map-out a course by driving it manually and using my 3rd channel to set waypoints. Then I can put the car in auto mode, and have it re-trace the course. It's pretty simple in theory, but took a lot of fine-tuning to get working.

Making this project work with ardupilot required a complete re-purposing of almost everything on the ardupilot. A few modifications were made to the board to facilitate testing, and a fully custom firmware was written. It's hard to say how things will go this weekend at the competition, as I will not have a chance to pre-run the course (until the day of the competition). In near-by parking lots, it performs well. I'm optimistic! 

Today I flew my Twinstar with APM in the hotseat. It's the second flight I've had with it wired in, but yesterday I was only using the stabilise mode. It's been a couple of great days from a weather and wind point of view, so ideal for testing.  The Stabilise mode is lovely.  The Twinstar (mine has a stock power system) when it is trimmed up is a super stable platform anyway, so I'm not too surprised that stabilise didn't have a massive impact, but it was certainly noticeable and very pleasant to fly!  The plane does have about a 5 degree nose down pitch when hands off (in stabilise) and I don't know how to fix this, can it just be trimmed out with the radio?  I thought the AP would compensate for any trimming I did to the control surface, and the fact that it has a nose down attitude is probably an autopilot config issue.

Return to launch was interesting.  I took off in stabilise mode and flew fairly straight away into the wind gaining a bit of altitude.  I then changed mode to RTL and took my hands of the control for the next few minutes.  The plane held attitude well, and executed well controlled turns.  However, you couldn't in all honesty describe what it was doing as a circle overhead the launch site.  Figures of eight perhaps, it seemed to be hunting for something.  It certainly seemed to be controlled and comfortable in the sky, I wasn't too worried.  I still don't understand it's behaviour though.

I would like to share the log file with you, but I can't.  For some reason this flight wasn't logged.  The previous two were and I have the KML and log files for those (not huge files, probably about 3-4mins flying each). Log three only shows one 'page' of data.

I will fully admit that this may all be my own fault.  I'm still learning, but in my excitement and the heady sense of progress, I havn't run the tests and tuning using FBW_A that the manual suggests that I should do.  I've not got my head around PID settings, and I suspect that this is the root cause of the issues i was seeing with RTL.  I'm guessing the AP couldn't hit it's mark to begin the orbit.

If the weather holds I'll be out again tomorrow to diligently follow the FBW_A tuning guide!

From IEEE Spectrum:

"Tokyo Electric Power Co. (TEPCO), the plant's operator, is using a T-Hawk [photo below], a remote operated flying machine created by U.S. firm Honeywell, to get a closer view of the severely damaged reactors.

The T-Hawk, known as a micro air vehicle, or MAV, uses a ducted-fan propulsion system that allows it to hover in place like a helicopter and fly into tight spaces where other aircraft can't go.

Last Friday, TEPCO workers, with assistance from Honeywell employees trained to pilot the T-Hawk, used the vehicle to survey the reactor buildings at Units 1, 3, and 4.

TEPCO has used manned helicopters, high-altitude drones, andground robots to obtain images of the facility. But the T-Hawk, because pilots can hold it in place and use its camera to zoom in on features, is giving TEPCO a better look of damages in and around the buildings.

The photos and videos of the latest T-Hawk survey, released on Saturday, show piles of debris, badly damaged walls, and collapsed roofs, with smoke still coming out of Unit 3. In some images of Unit 4 it's possible to see parts of the reactor and spent fuel pool."

Lots more pictures like the below and videos in the post.

After making my first UAV (few months ago)  LINK , i was recently having problems with space...............

Receiver, Ardupilot, Arduimu, Gps, Remzibis OSD, Motor Battery, Video Battery, Receiver Battery, E.S.C., B.E.C., Camera, Servos for Pan and Tilt,  video tx, telemetry,Etc.

So i decided to redesign the fuselage of my drone so it has a big and easy to remove compartment cover and lots of space to put everything and more...

In the first pic you can see the big white cover...... inside i will install everything....

Next Pisture, new fuselage Shown with cover removed and two 4000 mA, 3S Lipos inside.....testing the space

So, I'd been having some trouble with my first APM board - I found the X and Y gyros were not working - I tested the connections, and found that the ADC was working correctly, but I was not getting a signal from the leads of the actual gyro chip.  It's been way more than 30 days since I ordered it, so I could not return it to the store, so I decided to bite the bullet and order a second APM.  After soldering it together, it appears to be fully functional.  Now I should be able to get on with some of the ROS stuff I mentioned in the last post.

Here is some more info on my blog, as well as a video of my pre-flight check of manual and FBW_A modes:

http://projects.electrictoast.net/2011/04/pre-flight-mode-test/

I've also been able to test it with a both QGroundcontrol, and the mission planner GCS successfully, so I'm hoping for a test flight later this week.

On a sidenote, I noticed that Sparkfun came out with a USB interface board for Andriod phones - which could be an excellent way to connect an XBee directly to an android for a phone or tablet-based ground station.

I used Black RTV Silicone to keep the compass from moving during hard landings and wrecks.  I also used 2 header plastics to make sure my compass isn't to close to the IMU.

ABB, the world's biggest industrial automation company, is promoting a very impressive humanoid concept platform called FRIDA.  I want it real bad.  From IEEE Spectrum Automation Blog

"Traditional industrial robots are big, expensive, and hard to integrate into existing manufacturing processes. They're also difficult to reprogram when production changes become necessary and they can't safely share spaces with human workers. This barrier to entry has kept small and medium companies "robot-less" -- at a time when robots, more than ever, could boost productivity and ameliorate labor shortages…

To make it even safer, its motors have limited drive power and soft pads cover its body. The robot has 7-axis arms, each with a servo gripper for small-part handling. Inside the torso is a control system based on ABB's IRC5 industrial controller.  So what can FRIDA do? One scenario ABB envisions is using it to bring more automation to the fast-paced, and mostly human-powered, assembly lines found in the electronics industry."

Hello!

Practically everyone knows that the nev version of APM was released about a month ago, it's still beta now, however a lot of DIYDrones` community members moved on it and have some issues, misunderstandings, and so on during the tests. I was also among them. Finally, I have conducted all the major simulations in XPlane successfully and want to share with my experience.

I created two video tutorials (similar to which I did about APM 1.0 version, http://diydrones.com/profiles/blogs/ardupilot-mega-instructional) about HIL simulation using APM Planner GCS and HK GCS.
I hope they will be useful for community members, potential customers, etc. and help to learn more about APM 2.0

Here are the links:

HIL Simulation in XPlane using APM Planner GCS

HIL Simulation in XPlane using HappyKillmore GCS

Updated Video

Dear Friends,

after my last fly in stable mode i update the i2c libs for compass and barometer , now is better of older versions so i can upgrade main core loop to 800 hz instead of standard 200 hz .

Above the resutls of my first automatic flight , i'm very happy of this first result .. i start to use the performances of our Multipilo32 Arm Cortex M3 processors.

More Performances = More stability.

The firmware will be available tomorrow on our repo.

check Official link for more info : http://www.virtualrobotix.com/profiles/blogs/armfox-v4-gps-and-altitude

the next step will be to test sonar and start to work on ACM ...

Best

Roberto

I found this video to be an excellent tutorial for prop. balancing and wanted to share it. Hope it help a lot of our members to solve vibration issues etc.

"...I dont work for horizon hobby and i'm not saying or encouraging to buy products from this distributor..." before some one jumps and say something... lol  :)

Airframe #1 – Flight #1 – Who’s the U-boat Commander?

To make a long story short…Flew, crashed and ended up floating in the irrigation ditch.

After 2 weeks of 20 gusting to 50 winds I finally got a chance to fly… Winds were calm, a beautiful morning to fly.

The flight was airframe only, no payload.

I did a few “power assisted” glide tests to check trim and for surprises. The aircraft was a bit twitchy due to the enlarged control surfaces, I dialed in a bunch of expo to correct the problem.

The first part of the maiden flight held no surprises other than minor trim issues. ½ throttle provided more than enough power. The flight was going well, about 7minutes into the flight I got slightly bored…

Remember the wing strength concern? I did some medium power acrobatics, Loops and rolls and was having a bit of fun. I set up for a wide open throttle low pass and watched a rocket fly by. As I pulled into the climb out, I heard a popping sound as the wing buckled between the root and tail boom.

The next 30 seconds got quite “western” as I fought the flapping wing monster for a bit of control. I ended up bouncing off the bank of the irrigation ditch as a last resort to violating my hard boundary for the flight area. The aircraft ended up bouncing over the bank and ended up floating in the irrigation ditch.

Damage done:
Buckled wing due to high speed flight
Crushed nose due to ditch bank impact.
Broken wing tip due to recovery
Dead ESC due to water.

Things I learned:

It did fly and flew well when inside its airspeed envelope.

"Felt" very stable, makes for a good aerial photography platform

Very easy to build

Wing design has structural issues

Good payload bay volume

Did not do any payload capacity (weight) tests

The picture shows where the buckling occured.

Airframe #1 has been retired

Airframe #2 is on the drawing board

Design changes/additions for Airframe #2

Longer wing, 50 inches min.

KFM3 Wing

Better wing structure, 6mm x 6mm square carbon fiber tube as a full length spar

Strengthen or change materials for tail booms

 Strengthen the tailboom / wing interface

With SIRIUS I we present a fully integrated orthofoto UAS (Unmanned Aerial System). The system enables everyone to simply obtain aerial images and calculate orthofotos and three dimensional elevation models out of the image data.

An orthofoto is an geometrically corrected aerial image such that the scale is uniform. These pictures are necessary for applications such as easy and fast documentation of construction sites, disaster areas, survey of development areas, stone quarries or waste disposal sites. Other applications are environmental, traffic and wildlife monitoring with MAVinci’s autonomous UAS.

We are a young and innovative company. Our products are completely autonomous small airplanes with a wingspan of 2 to 5 meters. The MAVinci Autopilot is our own development. It allows for completely autonomous take off, flight and landing. All on board measurement systems run automatically and the accomplished data is stored in an on board memory. With our flight planning software, MAVinci Desktop, track planning before or during the flight is easy.

The complete aerial image process consists of three simple steps:

1. Flight planning
2. Aquisition of Images with SIRIUS II UAS
3. Post processing of the images

The MAVinci Orthofoto System connects all steps to one tightly integrated and user friendly toolchain. It comprises a flight planning software licence, a small fixed wing airplane equipped with a gauged camera, a groundstation and a post processing software license.


Typical wokflow:

The flight planning is done automatically after selecting the aerial image area. Flightplans can be altered before and during the flight. Hand-launching the airplane is our take off method, no catapult etc. is neccessary. The max. flight time of SIRIUS I is 55 min, aerial image mission time is 45 min. Manual control during the flight is possible with full manual or assisted flight mode supported by the autopilot. In this mode landing is possible on very small areas but autonomous landing is also possible. A vertical parachute landing feature will be available soon.

After the flight the aerial images are copied to the post processing computer. The interface between MAVinci Desktop flight planning software and several compatible post processing solutions (Photoscan, Pix4D etc.) enables easy post processing of the images.

Videos and more information about SIRIUS I is available at www.mavinci.de.

Well just as the tittle says, a new design is out and looks great, hope to see some of this props on the 9'' , 10" , 11" and 12" dia. size. 

For more info. here is the full article.

http://www.flyinggiants.com/forums/showthread.php?t=63180

As we all know when someone claims to have invented something that goes against the established norm we all are skeptical and we all raise a lot of questions. I was no different when I started following the thread created by Josh McBride (Ion01). Josh said that he had a patent pending revolutionary new idea for increased propeller efficiency, increased thrust, reduced load on the engine, etc. Pretty much all the things that we really would like but thought were impossible.

So when I received a p.m. from Josh asking me to check out this new product he has created I jumped on the chance. Without having any inclination of what he has done to this point, I met up with him at a local RC field in Guthrie, Oklahoma and, low and behold, there was something that I wasn't quite prepared to see. As you can see from the photo it looks like an exaggerated scimitar prop, until you do a double take and check the direction of rotation. As you can see the tip of propeller is forward of the hub. I must confess, I am not an engineer, but I do understand the principle of a forward swept wing. And that is exactly what this design is.

So now we get down to the testing! Josh had a standard Bolly 23 x 8 bolted onto the front of his DL – 50 engine that was mounted on his Double Vision. We ran the engine on the ground and it produced 6,800 RPM. I then flew the airplane through the entire flight envelope to get a baseline of flight characteristics. Josh then bolted on his propeller onto the Double Vision. This prop has the same diameter and pitch (23 X 8) as the previously used propeller. After warming the engine up again the tach read 7,500 RPM's, giving an increase of 700 RPM's over the previous prop. I know that rpm readings are not indicative of the actual performance of the propeller/engine combination but 700 rpm is a huge difference and I was ready to fly it and see. I proceeded to fly the plane through the entire flight envelope again. There is a distinct noise that this prop delivers, but it never ripped even when it unloaded. The engine responded quicker to throttle inputs and performance was improved in vertical maneuvers including pull out from a hover. I must add that it takes a lot of guts to design, develop and produce something this is completely different than what we are all used to. I applaud Josh for his vision and hope that he is successful in his endeavor. Thanks for being a Giant! 

One last note,I will be using one of these on my 50cc bird!

Current thread http://www.flyinggiants.com/forums/s...ad.php?t=56581
Website: http://revolutionaryprops.com/

Here are a couple of questions I had for Josh and thought I would share them with you guys:

Josh, What was your inspiration for this design?

I have always loved and been fascinated by the exotic look of the X-29 and the huge advantages of the forward swept wing. Then when the airline industry become so focused on the reduction of the wingtip vortex and the huge savings that resulted I began to wonder what could be done to a prop to provide the same improvements. In recent years RC Propeller designs have attempted to make the same improvements I was so interested in but I never saw a forward sweep. With the instruction of affordable carbon fiber construction, providing the strength necessary for the forward sweep, it occurred to me that material strengths must be the main reason this configuration had not be used in the past just like on aircraft. So, I figured this was my chance to finally bring the well known advantages of the forward sweep to the propeller.

Are there more sizes of props available?

Currently, we only have the 23 x 8 due to the start up costs but plan to bring many sizes to the RC industry and eventually move into full scale aircraft. In the short term, once we regain some of our expenses, our next prop will be for a 120cc and we will continue bring other props from there.

Do you have any data on the propellers performance other than RPM’s?

I was very careful during testing to ensure the only variable was the sweep of the propeller to eliminate any other “contributions” to the measurements/performance. I measured RPM’s, “wind speed” of the prop wash near the fuselage (important to 3D performance), and static thrust (those familiar with propeller design will realize that static thrust does not show the actually thrust generated in flight as a prop is designed to move through the air and not be static.) All measurements were taken at the same throttle positions in the same atmospheric conditions as well. All areas showed a clear increase in performance. I will have charts illustrating these increases on the website revolutionaryprops.com soon.

As this design is a departure from the norm, what would you say to someone who is skeptical?

The advantages of the forward swept wing have been known since the Germans first experimented with it in WWII. With the X-29 and the SU-47 the advantages have became well established. Considering it provides such large advantages to such performance aircraft it only follows that there would be advantages to a propeller which is really just a wing that rotates. Simply, it’s a simple, well known concept and I was just lucky enough to be the first to apply it in the most advantageous form on a propeller.

According to Federal "Report on DOT Significant Rulemaking" published April 14, 2011; the proposed SUAS rules were due in the Secretary of Transportation's Office (OST) April 14, 2011. No change in timeline was posted.

Is it possible the "milking" is over and we can put the cow out in the pasture?

Maybe Congress' FAA reauthorization Bills' amendments "inspired" them to get on with it.

I spent $42 at Lowes and RadioShack.  It took about 3 hours to build.

                                                    Specs:

                                                22'' motor to motor

                                                4.75'' Tall

                                               360 Grams

Parts List:                                                                     

Qty.           LOWES

1       1/16 thick ( 3/4 x 3/4x 48'')  AL  square tube                                                                          $16.68

1      Aluminum Fire Exstinguisher Sign 4''x16''       $3.96

2      1/16 thick 1/2 x 36'' flat stock                        $5.36

1      50count 5/32 AL rivets                                  $2.90

14    8-32 x 1 1/2 Nylon Machscrews                     $4.50

24    8-32 Nylon Nuts                                            $4.50

                RADIOSHACK

1       6x8'' Prepunched PerFBoard                        $4.00

                                                        Total         $41.90

I used silicon to help dampen Vibrations.                              Fisished Quad Chassi      

 ARM & IMU fit nice and snug.

If you want to have six modes, you'll probably have to configure your RC transmitter to do this. That's usually accomplished by mixing a two position switch and a three position switch on your transmitter.

However, no example is given as to how this mix might work. In the comments to this blog post Setting Flight Mode with Hitec Aurora 9 there is a method given by Juan Enrique that I did in fact get to work with my JR 9303, however, it only gives you 5 flight modes, and not 6.

For those that want the full taco, and have a Tx with both a 3-position switch and a 2-position switch, try the following mix. I've only tested this on my JR9303 but really it should be easy to translate to any other Tx.

1) Choose your two switches. For this example I am choosing:
- Flap switch = 3 Position switch (also called my Flight Mode switch on the 9303)
- Gear switch = 2 Position

2) Modify the end-point (or travel adjust) on your 3 Position switch. Instead of travelling +100/-100, you need to change it to +65/-65. On the JR radio, if you are also using the Flap switch, this will actually show as Up 65/ Down 65, but it's the same thing.

Don't mess with the end-point (or travel adjust) of your Gear switch, leave it at +100/-100.

3) Now create your mix. On the 9303 there are two types of mixes: programmable mix 1 & 2 are multi-point, 3-6 are "standard" mixes. While you could probably get the multi-points to work, don't bother, just pick one of the standard mixes. I chose mix #3.

You are going to mix your 2-Position Switch (Gear) -> 3-Position Switch (Flap). In some terminologies, the equivalent statement is that your Master Channel will be the 2-Position Switch, and your Slave Channel will be the 3-Position Switch.

Really the screenshots below will explain much better than I can in writing. Basically:

- When your 2-Position Switch is "On" (position 1), set the mix to the 3-Position switch at -17 for the 3-Position switch in the "down" position, and 0 for 3-Position Switch in the "up" position.

- When the 2-Position Switch is "Off" (position 0), set the mix to the 3-Position switch at -33 for the 3-Position switch in the "up" position, and 0 for the 3-Position Switch in the "down" position.

4) Confirm that you get the correct PWM measurements. Do this by using the convenient test mode on the APM (v2 only), accessible via the CLI. See this page for how to access the CLI: APM CLI. Once connected to your APM, type "test" then hit Enter. Next type "pwm" then hit Enter. Make sure your radio is on. You will see rows streaming by with the PWM outs for all 8 channels. If you have the standard setup your flight modes will be on channel 8. Confirm that by moving your 3-Position and 2-Position switches you get all 6 of the following PWM values, or close to it:

#5  --  1750  --  1815  --  >1815

#4  --  1620  --  1685  --  1749

#3  --  1490  --  1555  --  1619

#2  --  1360  --  1425  --  1489

#1  --  1230  --  1295  --  1359

#0  --  <1165  --  1165  --  1229

You can assign any flight mode to any number with one exception: Flight Mode 5 (PWM >1750) is ALWAYS manual. This can't be changed (unless you want to modify APM code yourself). The reason for this is the fail-safe.

To assign the desired flightmode to each of these numbers (except of course #5), you again use the CLI in the Setup Menu -> "modes" command.

Question: Since Flight Mode 5 is always Manual, what happens if you don't like the direction your Tx switches end up at? You can try two things:
- Use channel reversing on your 3-Position switch.
- For your 2-Position switch, you'll notice that reversing the channel on your Tx will have no effect on the PWM output. If you want to reverse your 2-Position switch, you have to modify the mix. Instead -17 and -33, change these mix values to +17 and +33, and swap their locations (from 3-Position switch "up" to "down" and vice versa). Again, see the photos below for clarification.

Question: What if my PWM values aren't exactly what you get? In this case, try adjusting the mix values. Note that if you increase one, you will probably need to decrease the other (so if you up the 17, you might find you'll need to lower the 33). The end-points also make a difference and if you want you can adjust those, but I think the +65/-65 is what you really want.

Hope this helps someone... It drove me nuts for hours.


Luke



Travel adjust / end-point adjust (different names for the same thing). Set your 3-Position switch to +65/-65 (here I am using the flap switch)



Mix your 2-Position switch (Gear in this case) to your 3-Position switch (Flap in this case) and have the mix be controlled by the 2-Position switch (Gear)



Alternate mix if you want to reverse the direction of your 2-Position switch (Gear in this case). To reverse the direction of your 3-Position switch, just use the channel reversing function in your Tx.


Example output of the "pwm" test program from the APM command-line-interface. Channel 8 is showing flight mode #5 (manual).

Dear Friends,

this is the video of first flight of Multipilot32 that use ArdupiratesNg32 rev. 2.01 firmware.

I ported to Multipilot the 8bit firmware , change all the library necessary to firmware and doing some small patch on original firmware.

At the moment i fly in stable mode + configuration with this PID (3.00 , 0.150 , 0.900)

As sensor i use Oilpan , in the firmware i don't yet activate GPS , BARO and Magnetometer , i doing some test but before to fly i need to optimize the i2c code and deactivate the debug functionality that degrade the speed of execution of code.

Some suggestions ? Do you like this test ?

This is the official thread of pre flight check of ArdupiratesNG32 v 2.01

http://www.virtualrobotix.com/forum/topics/armfoxv4-ng-32-and

info about the board : http://www.virtualrobotix.com/page/multipilot32-1

In the next day I update this section of discussion with some new tips and tricks

Best

Roberto

dAlH2Orean H2 R/C Car powered by Aluminium from Aleix Llovet on Vimeo.

Just in case you missed it in one of my other posts, joystick control is now working via my GCS. I need to write up a "proper" wiki page on how to use it, but here are the basics.

Download my GCS here: http://code.google.com/p/happykillmore-gcs/downloads/list

Edit your APM_Config.h file and add this:
#define ALLOW_RC_OVERRIDE ENABLED

Once you have your APM talking MAVlink to the GCS, click on the Joystick tab at the bottom left. Then select calibrate.

The calibration screen is used to set sub trims, servo reversing and end point adjustment. The first thing I would recommend (as I have not fully worked out the initial settings for this screen) is to select your joystick at the top and then select which mode you want to use (ie Mode 2) which will pull up the defaults for that mode.

Next Click "Enable" which will allow the software to grab the joystick movement.

Now move the joystick axis and confirm that the correct stick movement moves the correct throttle, elevator, aileron and rudder axis. If you do not wish to control an axis via joystick, select "None" under joystick input.

If you have previously used the radio calibration via the CLI then your endpoints should already be set. If not, they can be adjusted along with sub-trim (may be difficult to do on the ground) and you'll NEED to confirm your reverse settings! Next make sure you assign the servos correctly (actually, I'm not sure it can be set differently on the APM)

Throttle = Servo 2
Elevator = Servo 1
Aileron = Servo 0
Rudder = Servo 3

Now you should be able to move your joystick and see servo movement on the APM.

Here are a few things to keep in mind when using joystick control. 

1) If the radio output on channel 8 (mode selection) is set to "manual" mode, the joystick will not work. If you've used the GCS to select Manual Mode but your radio mode selection is set to something else, then the joystick will work. It's possible to use the joystick in every mode except hardware manual.

2) Radio control will not work until you unclick the "Enable" button on the joystick tab (or calibration tab). The APM will only listen to one input device at a time. As soon as you select joystick, it will only listen to the joystick until you disable the joystick function.

3) It is possible to run a joystick only calibration using the "Set Endpoints" button on the calibration screen. However, this is not the recommend way to do things as your radio endpoints must be adjusted as well.

4) Running the CLI's radio setup will over-write any end-point or sub-trim values you have set on the calibration screen.

Let me know if you have any problems!
Use at your own risk!