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Now available at www.aeroworksproductions.com in White and Black.

Manuals-

RVJET%20Assembly.pdf

RVJET%20PT%20Assembly.pdf

A 3D Robotics quad following Chris around the field. He is using a Nexus 7 running Andropilot for the FollowMe functionality.

Well, it was not exactly the real maiden as I did a bit hovering in the yard before but it was the first "real" flight in open area.

Setup:

• MF450 frame from eBay (also available from BEVRC)
• 4xTurnigy NTM28-30s 800kv (short shaft)
• RCTimer noname 10x45 props (BIG pack :D )
• Zippy compact 5000mAh 4S LiPo
• APM 2.5 / ArduCopter 2.91b
• Hobby King Wing Camera mounted on sixfold stacked double-sided foam tape

The quad is yet untuned. From my perspective, it looked pretty stable in the air with the default settings when I was hovering. From close up, I noticed constant small fast oscillation in pitch and roll which also show pretty clearly in the video. On the maiden itself, I noticed mainly huge problems with altitude hold. The copter would lose altitude over rather short time and generally be not very precise, as can be seen. Additionally, when switching to alt hold (I put alt hold to an override toggle switch), all motors go low, almost off for a sec and then spin up high. VERY scary, seeing the quad falling a foot or so after switching...

Now, about tuning. I have read around and I don't fully understand the tuning procedure yet. Well, physics class is 20-something years ago :). One issue is also that this little thing has amazing power and I don't feel comfortable holding it in my hand while tuning. I tried once shortly but when I tuned the RATE_P up with CH6, the motors suddenly spun very high and I almost let go, so no joy there.

I was hoping that somebody might have a similar setup and somebody could generally give some advice what do do about the fast oscillations and the alt hold problem. Right - forgot - it was a bit windy today. Wind was between about 0 and 2.5m/s.

My goal is to have a rather conventionally (read: boring) tuned quad for video and photo purposes. No aerobatics or wild FPV chases intended. Just mostly slow and stable flying and hovering.

http://xkcd.com/1207/

I finally got around to the X-8 maiden flight.  Nice day, gentle breeze, batteries charged and ready to go.  Things went as well as they could for a first flight.  The plan was to take off in manual, trim things out, then try stabilize and maybe even RTL.  Unfortunately when I switched to Stabilize the plane leveled then seemed unresponsive to my control inputs.  I quickly switched back to Manual before it flew into the ground and continued to fly.  I also had a few radio glitches for some reason which caused the APM to Failsafe to "Circle" mode.  Is that normal?  I should probably change that to RTL.

Here comes the bad news.  My "helper" was to film the ground to air footage for this video.  After the 6-7 minute 1st flight, I landed and he hit "Record", the whole flight the camera was on pause.   WHAT! @*%$!  Now my dilemma, the wind is picking up but I want some nice footage from the ground.  It's getting too windy to hand hold both the radio and X-8 with one hand each so how about this, I'll have my helper hand launch the plane while I man the radio?  After some brief instructions and a wind check, it was time for flight #2.  As you will see from the beginning of the video, things did not go as planned.  When he went to toss the plane he left his hand up and in the way and it was struck by the prop causing it to nose over into an uncontrollable dive.

So far the only damage I can find is both plywood wing flanges where the little screw goes through broke and I got a pitot tube full of mud.  I didn't like the wing attachment set-up anyway so now I have a reason to fix them.  By the way, he's alright and he only suffered a couple small scratches on his fingers.  Very lucky!

Moral of the story is, don't be rushed to make a flight if ANY of the conditions aren't right, always make sure the cameras are rolling and don't put un-trained personnel on the end of expensive equipment.

Hope you enjoy and if anyone has any comments on the Stabilize non-control issue please let me know.

Google Earth file-2013-05-01%2009-46-24.tlog.kml

T-Log- 2013-05-01%2009-46-24.tlog

Our head of manufacturing in Tijuana, Guillermo Romero, and his team: Elena Naranjo, Manuel Arriaga, Orlando Avendaño Gastelum, and Shiela Diaz have recently completed the introductory session of ISO9001:2008 certification. Quality management is an ongoing effort and something 3D Robotics strives for. We are proud of our products and want to insure they perform as promised -- quality manufacturing is a key ingredient to this goal.

Every weekday in May, we’re going to be sharing a glimpse of what we’re working on behind the scenes at 3D Robotics. You’ll see many of our projects, see the facilities, meet the people and maybe get some hints at products coming out soon.  There are more than 70 of us now — in three facilities — and we’re super busy,  so there’s a lot to show!

Today, I’ll start off with a teaser. What do you think the above is and how is it used?

-Chris A.

Some may be interested in the bicopter VTOL airplane and flying wing plans that will be available if the project at the below link gets funded. It's basically MultiWii quadcopter and bicopter VTOL code modifications done by me. I'll be looking into a possible port to the APM for volume 2 if this project gets funded.

The below flying wing doesn't takeoff vertically but I think it's unique enough to include in the plans offering. The below images are of the single motor version but the final one will have two motors as seen in the below video.

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After 4 months of work we finish to port AP_HAL library to VR Brain.

so now we are ready for test Arduplane on VRBrain and see our VR Plane fligh in the sky :)

In this video you can see only first test that we doing last week.

Our configuration are :

• VR Brain 4.0
• Mediatek GPS
• Radio Hitech aurora 9
• Battery 3S 1800 mah
• We decide to use a Sail Plane EasyGlider Pro for our first test , it fly very well :

We are using  3 servos configuration 1 for control the roll of plane connect to two servo ,  one for pitch control and other for YAW control.

We try to fly 3 mode :

• manual for have a full direct control of Plane .
• stabilize for control auto stabilization of plane when we putted the stick in the center.
•  return to landing , this is the fist automatic functionality that we test on our VR Plane :) It's work very well and when reach the point start to Circle .

Fly a Plane is a lot different that fly a Multicopter , I fly for 4 years only multicopter but my first impression is that the plane fly in more natural way than a multicopter ... less problem .... more simple to control  but could be only a first impression :) 

So the plane have a lot of limit respect of Multicopter but it could be a very long flight time respect to Multicopter especially in Sail Plane configuration.

The video is developed by VR Media division , the Chief of division is Daniele that's  our beta tester of  VR Plane.

Thanks to the DevTeam and beta tester  for this great result.

original blog post : http://www.virtualrobotix.com/profiles/blogs/vr-planer-first-flight-test

Best

Roberto Navoni 

Alma, Québec – April 22^nd, 2013 - The municipal Council of Alma, Unmanned Systems Canada, the Alma Airport authorities and the Unmanned Aerial System Center of Excellence are proud to invite you to the 2013 Unmanned Systems Canada Student UAV Competition.

Close to a hundred students from across Canada will attend the competition from May 3^rd to 5^th. They will fly their own UAVs and complete various tasks such as detecting and decoding targets. Colonel Paul Prévost, Commander of the 2 and 3WING Bagotville, has graciously accepted the honorary presidency of this year’s event.

This 5^thedition of the competition and is the first to be opened to the public. Anyone fascinated by the world of aviation and willing to learn more about UAVs are welcomed to attend on Saturday May 4^th and Sunday May 5^th between 9am and 5pm. The public is invited to tune their radios to the regional stations of RNC Media, Planète and Radio X stations, to hear capsules throughout the weekend. The admission is free for the children under 12 years old and of 3$ for the people 12 years old and over. Various activities have been organized for the public. One of the highlights of the weekend will be the Fly-by of a CF-18 Saturday at noon. Many booths and aircraft on static display will be set up for the spectators. UAVs will also be on display, including the MISKAM UAV that has been flying and tested in Alma for over a year. Other businesses interested in the UAV development will also be on display and presenting their services to the public.

“This year, the Unmanned Aerial Center of Excellence and the city of Alma have graciously agreed to host the event. The fifth edition is shaping up to be the best event to date; we are looking forward to it. The continuous success of our Student Competition is directly linked to the support of our sponsors and the host city” states Paul Drover, executive director of Unmanned Systems Canada.

“The City of Alma is proud to host the Competition. For the first time in Canada, the event will be open to public. The whole region of Saguenay-Lac-St-Jean will benefit from the competition” adds the Mayor of Alma, Mr. Marc Asselin. “The Unmanned Aerial System Center of Excellence is constantly evolving and, by hosting the competition, the UASCE is demonstrating its leadership role in the UAV development at the national and international level”, states Pascal Pilote, president of UASCE.

The Unmanned Aerial System Center of Excellence has recruited over 60 volunteers to deliver this major event, which will attract many new companies and sponsors from across Canada and the United States. The sponsors, as well as all team members, their coaches and the organizing committee will be staying in Alma during the competition. Many local businesses generously agreed to sponsor the event and they hope to benefit from the national visibility. The competition will likely provide an important economic impact to the city of Alma.

 Canadian student UAV competition

Unmanned Systems Canada (USCSTC)has been organizing the competition since 2007. The main objective of this competition is to promote and develop the Canadian expertise in the UAV sector at the colleges and universities level.

The Unmanned Aerial System Center of Excellence (UASCE) works toward becoming an international center of expertise and to offer innovative services such as manufacturing, research and development, testing and training. The student competition being held in Alma is a great opportunity to promote our services and to inform the public on the purpose and uses of UAVs.

Let the Competition Begin - A Hundred Students Set To Fly Their Own UAVs

Hey everyone!  We finally got a small shipment of these in and have a few left.  Available now at www.aeroworksproductions.com  Specs are available on our website.

Available in Black and White!

I've flown a lot of different planes while working on ArduPlane, but it wasn't till yesterday that I first flew what is perhaps the most popular plane for new ArduPlane users - the Bixler2.

While setting it up on Saturday evening I had a bit of a look through some Bixler build logs in the forums, and I was surprised to find that none of the suggested ways of mounting the APM were really convenient. Some people put it in the bottom of the fuselage, which makes it difficult to get cables to, and hard to work on. Some used custom or commercial mounting systems for putting the APM on the top at the front, but that makes the Bixler less aerodynamic, and trying to cram all the accessories like telemetry radio and GPS in makes it a tricky fit.

The solution I came up with is to mount the APM upside down on the underside of the canopy. ArduPlane has supported the AHRS_ORIENTATION option for a few releases now, which allows you to have your APM mounted in a lot of different orientations. In this case it seemed perfect to use AHRS_ORIENTATION=8 and mount it upside down on the bottom of the canopy. The advantages are:

• it is easy to get at the APM for programming it, or accessing the pins, as you just pull the canopy off, and the APM comes with it
• when you remove the canopy it makes it easy to get to the battery space, as the APM is out of the way
• it leaves plenty of room for the receiver and GPS on the top part of the canopy
• it is clear of any wind effects, well shielded in the fuselage

I also used a pin through the plastic top of the canopy to hold the canopy on more firmly, as I don't really trust the magnets. You will also notice a couple of pins stopping the wings coming loose - those fuselage screws are rather loose and one came loose on the first flight.

This mounting system is also ideal for a PX4. I happened to use an APM2.5 for this build as I was doing bench tests on my PX4, but either one works with the AHRS_ORIENTATION option.

One thing to watch for with AHRS_ORIENTATION is that you need to reboot and then re-level your plane after setting it. It is best to use the CLI full accel calibration, so it can properly adjust for the slight pitch of the canopy bottom surface.

Cheers, Tridge

Airspeed control is critical when flying sailplanes.  You want to fly close to stall but never beyond it, since that will normally cause a tip stall and great loss of energy.  How do you teach an autopilot to fly on the edge of stall?

One solution is to teach the autopilot about the aircraft geometry and aerodynamics.  First you start with the wing section.  From the wing section you can use a simulation tool to generate aerofoil polars (picture above from XFLR5).  These polars describe the lift, drag and moment coefficients generated at different airspeeds and flap settings.

From the aircraft position and the amount of corrective pitch movement you need, you can calculate the acceleration you require from the wing.  This is known as load.  From load, geometry and aircraft mass, the lift coefficient can be calculated.

From lift coefficient and the wing polar you can calculate the required angle of attack for the wing.  From the required angle of attack, you can calculate required elevator pitch.

From the wing polars, you know the maximum possible lift coefficient.  Now you can avoid increasing angle of attack beyond Cl(max) and avoid stalling.  This is only half of stall prevention.  The other half is in energy management.

Both when gliding and under power, the aircraft loses energy due to drag.  For a glider this determines the descent angle.  For a powered aircraft it determines the engine power.  By using the estimate of drag coefficient from the wing section polar, the autopilot can set the target climb/descent rate and pitch angle.  When power is applied, it adds energy to the system so the estimated climb rate and target pitch increases.

Working in combination with basic estimated climb rate is airspeed error feedback.  Airspeed error is converted into meters of potential energy error and added to the target pitch.  The combination of target estimate and energy feedback are great for stall prevention.

Document describing airspeed by energy management

If you change flap settings then the wing polar changes.  As the flaps are changed, the autopilot has to interpolate between the different wing flap polars.  The result is a smooth transition between airspeeds.

This method also automatically re-trims the elevator for different airspeeds.  It also automatically does airspeed control fadeout.  It also reduces dependency on PID gains.  Some optional gains are still required for different flying styles.

One problem with this method is that it relies on knowing the initial wing-elevator incidence.  At high airspeeds the aoa is small and sensitivity to change is high.  The solution is to have a feedback from the accelerometers comparing to calculated load.  This error feeds an integrator which retrims the elevator.  The result is an even better trim for low speed flight.

Despite all the stall prevention, my first test flight resulted in terrible tip stall when turning downwind.  Adding a little bit of extra airspeed command resulted in lovely smooth turns.  When I went back to the estimated airspeed calculation, I had set airspeed setpoint 2m/s too slow.

If this all sounds new, it isn’t.  It is simply re-applying the basics that we know about aerodynamics.  If you are interested in aerodynamics basics you might start here

The project is based on a branch of MatrixPilot based here:

https://github.com/crashmatt/MP_Aerodyn

The original Matrixpilot project wiki is here:

https://code.google.com/p/gentlenav/

Aerodyn uses the MatrixPIlot code base for hardware drivers and IMU.  My thanks go to the MatrixPilot team for their support and innovation.

The Aerodyn project also uses a flexible field programmable mixer which is used to move the flight surfaces with accuracy.  This is used to fly this 5m, 10 channel aircraft.  More about that later.

New ArduCopter, ArduPlane and ArduRover Wikis are Operational (provisionally)

The old existing Wiki(s) are no longer getting updated on a continuous basis so you need to start using the new Wiki(s).

During this transition you will need to use both of them (although for the PX4, the new one is the only way to go.

The picture above is of my new F330 Flamewheel with PX4FMU and PX4IO flight controller.

This is main board normally put on Gimbal frame near the Quad . 

This is the two options imu available normally is on camera module: 

2 axis with 3 accelerometer and 3 gyroscope 3 magnetometer in one version we use mpu6050 and in other we use mpu 9150 1 chip 9 DOF sensor.

Some friends start to design different kind of gimbal for our new board. The main difference respect of standard gimbal is that the mechanical frame need to be develop for each video sensor that you would like to use for your video. This frame is for Gopro Hero 2-3 in the design is important to move CG of camera for obtain better result during gimbal stabilization :)

This is the caratheristics of our : VR Gimbal :

Micro Controller is STM32F1 at 72 mhz.

3 Axis Brushless Direct Drive gimbal :

• Roll    (MOT1)
• Pitch  (MOT2)
• Yaw    (MOT3)

For each channel we have 3 high power pwm output .

I2C IMU that support 3 axis . It  is on camera module , so we can know exactly the position of camera and control in realtime the 3 Brushless motors.

We are developing two option :

• more traditional approach : MPU6050 (6 DOF) + HMC5883 (3 DOF)
• new sensor from inversense MPU 9150 (9 DOF)

1 USB port.

1 Serial port that support mavlink protocol.

1 Power module that support until 3S battery.

4 Radio RC Input for :

• Control ROLL Setup.
• Control Pitch Setup.
• Control YAW Setup.
• IR control repeater.

4 Analog Input 0-3.3v

1 IR Out , so is pssible to control a remote camera by its ir receiver.

The first batch of production will be available in 3 week it's better to reserve your board because there is a big request of this gimbal.

for more info send a mail to info@virtualrobotix.com

original blog post : http://www.virtualrobotix.com/profiles/blogs/vr-gimbal-is-coming

Best

Roberto Navoni

I have been looking into my own method of mounting the APM with antivibration in mind.

To this end I wanted to source some freely available components specifically designed to reduce vibration.

I found a couple of such products which I am hoping will be ideal.

These coupled with a custom mounting plate, I am hopeful it will be a good solution.

First the mounting plate which will be cut from 1.5mm carbon fibre.

In each corner of the above plate will be an antivibration softgel bush which allow the plate to "float" on the main construction plate.

The APM case is then fixed to the mounting plate using SoftGel 15mm x 15mm x 5mm cube pads.

I'd be interested in any views people may have.

I have the parts here ready, but thought i would throw my prosal to the masses before the CF plate is cut.

Steve

As is customary and traditional, we celebrate every new 1,000 members here and share the traffic stats. This time it's 38,000!

There were almost 1.9 million page views in the last month! (we get around 65,000 pageviews a day on average). It took us just 22 days to get this latest 1,000 members--we're averaging one new member every 32 minutes.

Thanks as always to all the community members who make this growth possible, and especially the moderators who approve membership applications and blog posts and otherwise answer questions and keep things ticking here.

Best Wishes,

Joshua Johnson - (Assistant Administrator)

***Special Announcement***

April is Safety Month on Diydrones.com to check out how you can help (Click Here!)

I’d like to share my experience with my copter (aka ZuCopter) during my first full test using AUTO mode. My quad is ArduCopter, 3DRobotics Quad-C frame using APM 2.5 Firmware 2.9.1b

The plan was to go around the house, full automated, including takeoff and landing. This was executed quite smoothly at the first run J, Then I said… let’s try that again; I relaunched the same mission without turning the copter off or resetting, and…. something didn’t go so well: the quad decided to go full throttle without following strictly the programmed waypoints. I was good to have RTL mode programmed on my radio, so I was able to recover the flight back to manual mode.

This was the original plan:

The first run was quite well done I would say. Only thing I noticed is that arducopter do not strictly reach the altitude set at the waypoint. When it reaches the waypoint, it doesn’t matter if the altitude is lower, in contibue both increasing altitude and continue to the next waypoint.
From the data extraced from the LOG, you can see the waypoint altitude was reached only after waypoint 6.
Blu data are altitude requested by WayPoint Command, and the green is the barometric measurement.

This is the first run importing the .gpx information from the arducopter datalogger to Google earth.

As for the second run, I executed it using the same mission, without changing the mission nor switching off the quad. From the video you can see the strange behaviour:

• Copter not heading straight (camera, which is the head of the copter, was instead on side)
• Throttle-out was 100% most of the time during auto.
• Waypoints were passed very large

Then I prefere to engage RTL to bring the copter back home.

This was the first run from another angle:

And this is the second run where you can see the different copter modes I set. The yellow below was the original AUTO mode, blue STABILIZE, red RTL

As you can see from the datalogger below, most of the yellow line (throttle-out) during the first part of the flight is set flat to 1000. So full motors.

The image below was merged to the mission mode sequence: yellow area is the lower graph is the AUTO MODE (graph below is gathered by importing to excel the logs and trying to align them as much as possibile to verify what happened in what mode; it is not perfect).

The last thing I do not understand, is:

• why during the RTL the altitude decreased from 50mt to 10mt and I had to switch manual again to bring it back to a correct altitude?

I am attaching my log to this just in case somebody have any idea.

Overall I had quite fan, and was pretty happy I did program the RTL mode easy to be selected from my Radio switch.

 --Alberto

2013-04-26 10-50 4-log.zip

2013-04-26 10-50 4_Analysis.xlsx

Hello everybody,

This is my first, of hopefully a series, DIYDrone blog post.

The Hill Cruiser is the topic of my university thesis, which is to build an autopilot for an RC model plane.

Of course, I was inspired by the ArduPlane and the UAVDevBoard/MatrixPilot. Many thanks to you people for letting me see what I am capable of.

Consequently, I 'd like to start giving back to the site. I 'll start by posting a short presentation of the system I built, that I will be presenting at an EE student conferenece tomorrow. It's not very detailed, it's supposed to last 15 minutes.

I hope that I 'll be able to post the detailed multi-paged thesis document by the end of July.

This is the presentation .pdf:

Hill Cruiser - Conference Presentation

 Some things I 'd like to note:

1. I 'm waiting for a PCB from China for the main board. It will house the barometer and the pitot tube sensor and thus these are not implemented yet in the control system.

2. I know that my PID gains are off. I haven't had the time to tune them to perfection but the system operates, albeit the oscillations.

Feel free to post your questions.

Cheers!