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Great way to learn how to better use your Xbee's

http://www.sparkfun.com/products/10728

I have been a little mystified when or if the FAA is going to produce a set of sUAS rules, especially with some of the language in the looming FAA re-authorization bill. And when the FAA pushes its NPRM deadline back several times because of "Unanticipated issues requiring further analysis" it does not exactly instill confidence. Well today as an attendee of the UAS Summit in Grand Forks, ND, I had the chance to hear the current status from the horses mouth. Rick Prosek, the manager at the FAA's Unmanned Aircraft Program Office stated the following points.

-The FAA internal sUAS rule making team had reached "concurrence" just this last month (5/11)

-He anticipates publishing the NPRM in the fall of 2011

-The final rule will most likely be enacted mid 2013

Now I understand that this may not be a dramatic change from what has already been projected, but for me it was mildly re-assuring to hear the updated timeline from a real human being.

Pictured is my first attempt at a camera system comparable to what you would find on a commercial UAV. I hope to make available to the DIY Drones community a light weight, affordable, and highly accurate turret compatible with APM or any other open source autopilot system.

The goals for my design were:

1. Light weight for use in fixed wing and heli applications

2. Ease of manufacture/part replacement

3. Low(ish) cost

4. Highly accurate closed loop control in both pan and tilt

5. Continuous rotation in pan

6. Gyro stabilization either through an autopilot or standalone IMU

7. A design easily expandable to carry larger cameras (GoPro, and Sony block cameras are in the works)

My first iteration has succeeded mostly in hardware design, although the software is currently a work in progress. My goal is to connect it to an APM via I2C, and control it via a joystick on the ground. Obviously there's a lot of work left in that regard...

Turret control is handled by a Pololu Baby Orangutan robot controller. The Orangutan has a dual H-bridge to drive a pair of servos modified for use as gear motors. Being ATmega based however, pwm or steppers will work as well. It runs the Arduino PID library with input from two magnetic rotary encoders for precise position input.

Any input on software development would be appreciated. I plan to make this available as soon as it's ready, and it's going to be all open source, of course.

More info/pictures available at www.AUV-Research.com.

Cheers!

Seth

From IEEE Spectrum: "It's a well known fact that animals from the Arctic to Africa have absolutely no idea what to think about robots. Taking full advantage of this phenomenon, Microdrones let one of their MD4-1000 quadrotors loose on safari in Kenya, and it set about capturing video like you've probably never seen before."

Jason and I tried this last week with a coyote in Concord, and we can verify that it was totally unafraid of a quadcopter.  We got as close as we dared, and he didn't budge.

This is my Arducopter, now customized with a Hobby King´s frame that i have painted in Orange and black...

The HK´s frame parts fits nicely, and the arducopter parts got in to the frame really easy, plenty of room for the ESCs in the arms, the motors fit in their places and the power distro board gets in to its place in a cool way :-)

The APM is mounted in some plastic spacer that came with the frame, in the pic you can see also my receiver installed with double sided tape, i still have to decide the GPS location......

The only thing i want to do better is the landing gear, seems to be a little weak....

Hope you like it.....

came out with a 6-way mode switch.

the solution that will make your life easier. REALLY.

First to credits - Max Levine has firstly shown this method here, using 'off the shelf' resistor values, which might work, but keep on reading to find out why exact values are important.

i came out with a small rotary switch, that fits EXACTLY the space in Turnigy 9X.

it is intended for replacing the PIT TRIM knob. top left of your radio.

i calculated and found out the exact values that will give nearest PWM values to these needed by the APM to stay reliable in the middle of the position range, which means no accidental mode switching.

HOW TO GET IT ?

You can get it now - with low cost WORLDWIDE SHIPPING

please check out the 6 position mode switch for ardupilot on ebay

No more mixing and setting for 2\3 way switches of your radio !!!
No more hard-to-remember switch combinations !!

Some theory and explanation:
there are 6 slots for 6 positions.
the PWM value is detected and according to it - the position(and flight modes) are set.
these are the position SWITCHING POINT values: 1230, 1360, 1490, 1620, 1760
which means, we have to target the MIDDLE of the switching points to stay on a certain mode, with the safest margin from the switching point value.
except for the first and last positions (0&5) where we can be even safer, choosing the very first and very last value of range.
you end getting this as IDEAL pwm values for modes:
1085 (or lowest your radio will allow)
1295
1425
1555
1690
1920 (or highest your radio will allow)

Now the catch
mathematically it's easy to calculate the needed resistors, because these are steady steps, and could use the same value resistors.
BUT IN PRACTICE my testing have shown that the resistance scale is not totally linear with the pwm values.
the reason is quite simple - the radio seem to use some resistor on the incoming +5v rail to the voltage divider (the pot trim) - to limit the current going to the ADC reading chip when the pot is set to full 5v side.
thus the center of the pot (or other resistor) won't give the center of the ADC reading needed.
at least that is what i found with the Turnigy 9x which is very popular. i believe other radios are behaving similar.
This is the reason that probably different radio gear will need different resistors values,
and for the same reason I RECOMMEND THE PRODUCT FOR THE TURNIGY 9X RADIO which is the one i used to find the values. I found the best values to use are (from the GND side to 5v side) 3k9,1k3,1k3,1k3,2k2. all 1% tolerance. can't guarantee it will work at exact values with other gear.

What I've done:
since reliability can't be achieved using 'pre-calculated' values resistors,
i have done careful testings for the exact resistor values that gave the nearest possible to the ideal PWM values above.


Why get it ready made ?
- the price is really similar to ordering the parts individually with shipping costs
- I use high precision 1% resistors which are harder to find - which lead to better accuracy on the values.
- I use a switch that FITS the radio for sure. no guessing...
- it's easier, faster, and doesn't require lot of work to install.
- all switches are tested to be working and for correct PWM values

This handy pocket camera offers stunning HD quality video in a compact and light weight package. With support for up to a 32gb Transflash card (Micro SD) you will be able to shoot hours of HD 720p footage.

Specifications:
120 degree wide-angle HD camera lens,
5 Megapixels COMS sensor
Video resolution: 1280x720p 30fps
Selectable video quality: Superior/Standard/economic
Unique motion-detect recording function
Selectable motion-detect recording time: 10sec, 1min, 5min, 10min
Unique loop recording function
Photo resolution: 2560x1920 JPG
Built-in high capacity Lipoly battery provides up to 3 hours of recording
Memory slot: Transflash (Micro SD) support up to 32 GB
Size: 74mm x 28mm x 15mm
Weight: 29.4g
PC camera function
Support AV out
USB2.0

Price is US$ 37.18, more information at the Hobbyking website

I had read about issues or concerns with vibrations and gas/nitro powered planes so I come up with a vibration damper assembly made up of 2 fiberglass plates separated by 4 foam ear plugs that I cut the tips off and glued to each piece.  On the lower board I also mounted my receiver and the airspeed sensor.

Hobbyking is selling a similar board as the KK Quadcopter board.

Based on the popular and already well supported KK Control board, the Hobbyking Quadcopter control board is bringing Quadcopter madness to the masses with its breakthroughs in quality and price!

The HobbyKing Quadcopter control board uses Japanese Murata piezo gyros that are less sensitive to vibration than SMD type gyros and also features state of the art SMT manufacturing to ensure quality. This board also uses a user programmable Atmega48PA IC.

Specifications:
Size: 50.5mm x 50.5mm x 23.5mm
Weight: 14.5 gram
IC: Atmega48PA
Gyro: Murata Piezo

Price is US$ 29.99. I think it is important to mention that Hobbyking has announced on their forums that a part of the profit of this board goes to the original designer of the KK board.

More information here at the Hobbyking website

The autopsy was finally done on Vika 1's final crash, on Sep 27, 2010.
No idea what caused the crash.  The best theory was mechanical failure
of the tail rotor servo horn.  The original theory was a lucky PWM glitch sending

the servo into a safe mode.

The final autonomous flight of Vika 1 was skywriting.  Then we took
manual control & she lost yaw control.



But the golf course finally had a rare sight:  An intact airframe after
nearly 14 minutes of flying.  The tail servo is cracked.  She has a new
computer which will probably need serious rework before full autopilot
returns.  Last year's configuration values, written by a much younger

lion, still worked.

A lot of work went into removing PWM glitches & powering down the

servo when not flying, to maximize life of the brushes.  Turning the pin to an input

doesn't work, because current leakage causes the servo to glitch.  It really needs a 0

level, which makes optimized PWM code a lot more complicated.

We've concluded the most valuable flight controller with today's
technology is not a full autopilot but a stabilizer.  GPS isn't cheap
enough to get the mm precision in the movies.  Energy storage isn't
cheap enough to have a fixed orientation platform in the sky.

MARCY 1 AIRFRAME WRAPUP

The Marcy 1 airframe seems to have converged on the most stable & efficient design.



Embry Riddle guy recommended replacing the winglet with dead weight. Put
2g of mass on the wing & the RPM decreased to the 250 range.  The weight
increased the angle of attack by weighing down the wing.  Started
installing sonar pieces.  Stability seems improved.  High winds have
dominated, except for 1 day a week.

There were a lot of parameters yet to be explored in last year's
design.  With the weight, she's very stable.  All our designs have been
stable with no cyclic, but the weighted wing is the most stable with
cyclic.  A bit surprising how stable such a low RPM could be.

Flight time with any battery is 11 minutes.  The damaged one may not be as

damaged as thought.

The throttle induced banking in enough wind can actually become too
steep & gimbal lock to produce serious oscillations. 




That's how the wing is fabricated.

The main problem is getting equal lift for all cyclic values.  A
constant throttle multiplier worked slightly.  Constant RPM when pulsing
the motor doesn't produce constant lift.

The sonar array was revived, a year later.  Surprised how well it
works inside.  We put a lot of energy into perfecting sonar.





Recall how this sonar array evolved, in a time before Major Marcy, 1000 years ago.



Decided the range was being reduced by the environment, so a conformal
coating was finally in order.



Most important is where the microphone connects to the 1st amplifier
stage.



There is a beauty in through hole soldering, even though it only goes in
the 1 Mhz range.

Sonar remains useless with this aircraft.  It could be the spinning, the
coning angle pointing the emitter sideways, or the wind destabilizing position too much.



Hole 13 was your best shot at an autonomous flight. It's the most wind
sheltered area.

Hole 13 definitely had no wind, but was too small.  Hole 11 is
definitely a hurricane.  Ran around the golf course for 90 minutes.

Radio is bulletproof, with the conformal coating.  The days of falling
out of the sky & smashing are over.  Every landing is under radio
control.

Finally, for the copter fans, it's a rare confluence of having an HD cam, the HD cam working, & an MD 902 landing near the HD cam.

The Armfox V4 is my experimental platform for develop Flycam .

In my development i'm using :

Multipliot 32 : http://www.virtualrobotix.com/page/multipilot32-1

VRIMU : http://www.virtualrobotix.com/page/vr-imu-10

VRI2C ESC: http://www.virtualrobotix.com/page/vr-bl-controller-10

The firmware is ArdupiratesNG 32 that i had implemented with some new libs and functionality :

I add the support to 1 wire PPMSUM radio as Jeti to have on 1 wire until 12 channel that could be usefull for fly cam application .

I add the support to i2c esc so the refresh rate of esc is 2.5 khz instead of 550 hz available on standard esc.

On VRIMU is available a professional sensor ADXRS 610 gyro for high precision and high immunity to vibration. the full scale of sensor is 300 °/S and the resolution is 12 bit.

With this kind of configuration is available a lot of 16 bit pwm output for manage high quality sensor for gimbal managment.

Best

Roberto

It's been several month, since I started this project, and this project is not moving forward as I have hoped and anticipated, due to my lack of expertise and technical diffulties involved.

Diy Drones have a lot of talented people that they actively comment and exchange great ideas, and I like to share my frame design and I'm also hoping to hear from them technical advices on my project.

The object of this frame design is A: smooth transition from vertical take off to winged horizontal flying, that matches fixed wing aircraft type by utilizing detachable, adjustable pitch, foldable wing design. (To increase fly time, to cover larger area, to increase flying speed).

Object of this frame design B is to fly Quad in vertical orientation, so that Quad can fly in the tight area where conventional Quad or Heli can not go through, when wings are detached.

Object of design C is to incorporating Solar Cloth in winged area to charge batteries during thermal soaring, if that is possible in this wing design that still is on my to do list.

This Tamiya Gear Box is already built into carbon frame, and I have shorten that longer axle to be fit into carbon frame. and this gearbox rotate both props (one on each side axis of gearbox in 180 degree).

Servo control board and pot from Futaba S-148 was used, and control board gets too hot to drive this gear box, and I had to look for alternative. (Poloru motor controler that I will need to program).

Vertical flying orientation (visualize prop is facing up!), In order to control tilt rotors (two rotor on the top of picture rotate by single gear box as a pair, and two rotor on the bottom is rotated by another single gear box as a pair).

In order to make this possible,  I need remote XYZ sensors (Accellometer, Gyros, Magnetometer) that can tilt with rotor. (trying to tilt APM or whole board in the center of picture is too complicated, so I'm looking into to use Sparkfun's SEN-10321 instead of using built-in XYZ sensors on IMU or Oilpan), which I don't know how).

That is my problem number 1, and I  need suggestion  or comment from the board members who knows how. Another challenge that I'm having is that "how to connect rotor tilt funtions to APM", so that pitch can be controled by APM (not by using mixer control of receiver by using Y connector off receiver).

SEN-10321 sensor board is small enough to be mounted on the bottom of tiltable motor base in the picture above.

I'm using NG code now, and planing to migrate to current code, when I know how to acomplish those two challenges.

Specs on this Quad are; Motor is turnigy Prop Drive NTM 35-36 hacker 1400 kv 875w, apc 12-6 electric prop, apc 9-6 electric pro, 80amp turnigy super brain, 4s 5000 lipoi, total weight without lipo is 5.6 pound, tested runtime as is with single 4s 5000 lipo is 16 to 18 minutes.

Above picture is detail of motor mount and two props attched on motor axle.

Picture above is a bottom of Quad center that have room for 3 4s 5000 lipo.

Picture above shows rotating white servo horn to be attached to future wing, and provide pivot functions to the wing.

Also, how do I respond to my blog comments?

Guys is it just me or is this plane an exact Easystar clone? It's called 'The Bixler' named after Josh Bixler of the Flitetest youtube series. Here's the review and the link:

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=16542

I have done a few test flights with ArduPilot Mega at the recent weekend. Everything was perfect and I decided to make a video about operating with APM at the field. I hope it will be interesting for newbies and useful for those, who wonder how APM works in real conditions.

Well it has been quite long since last update...

the project was kinda delayed....

almost all of the hardware arived.

soon all parts will meet each other... to create the greatest of all..... the.. ____ (still looking for a name)

I've been drilling the arms to make the frame lighter...

it was about 470g, now it's ~420g.

i'll keep on drilling the arms from the horizontal side a bit

some stock of composite 12x45

apm, imu, sonar, gps, magnetometer, soon also telemetry

motors and ESC junkyard:

motors and ESC soldered and tested:

and now for the surprise...

a DroneCell with a SECOND GPS.

which are currently under development.

this standalone device will, once completed, send GPS coords over text messages to my cellphone.

this will help to find the copter if it gets lost.

Turnigy nano-tech 4S 6000mAh are on the way,

video TX\RX also on the way,

left to build is the DSLR camera mount... which is basically existing, just need to add the servos.

i'm waiting a 150g 33kg servo. will provide a smooth and powerful movement.

I know,

this is lots of stuff but not many work...

i soon will have more time for this, and i promise a kicking beast.

A 10 Km full autonomous flight of the MAJA drone with an ArduPilotMega

The MAJA drone has successfully done a 10 Km autonomous mission under flight plan on May 28, 2011. The purpose of my mission challenge is to succeed in a full 10 km autonomous navigation under a flight plan (FPL) with only the steering of the ArduPilotMega and its firmware (v2.2f JLN).
- All the 8 waypoints of the MAJA drone has been defined so as to be in line of sight of the pilot (me) who is able to override the autopilot and take the manual control in case of emergency.
- An automatic RTH (Return To Home) has been programmed in case of failsafe conditions (i.e. LOS (Loss Of Signal).
- The FPL is composed of 8 waypoints and the MAJA drone autopilot runs the FPL during 3 loops of about 3.35 KM. The full flight have been recorded with a GoPro HD wide camera.
- The MAJA drone is fully steered with an ArduPilotMega (APM v1.4) autopilot with a 9D0F IMU and the firmware v2.2f (JLN modified version based on the original APM v2.1 firmware).

The battery level, the RSSI level was monitored by the M-Link telemetry on my Royal PRO 9 (Multiplex) transmitter. After a 15 minutes flight time the Lipo (3S,11.1V 3300 mAh NanoTech) power battery level was 37%.

The weather conditions: Wind 16 Km/h from West.

The MAJA drone setup:

Avionic setup:
 - ArduPilotMega APM v1.4 (Atmega 1280 @16 MHz), 32 Mips
 - Full 9DOF IMU,
 - Built-in 16 MB Data Logger,
 - Airspeed and absolute pressure sensors (Bosh),
 - triple axis magnetometer HMC5843,
 - 10Hz Mediatek GPS MTK v1.6,
 - Full high speed telemetry with MavLink protocol,
 - Low speed telemetry with M-Link,
 - High Speed Telemetry (Mavlink).
 - PC Laptop ground station (APM planner),
 - Hand-held groundstation (Ardustation),
 
Firmware: APM v2.2f (modified version by JLN)
Camera: GoPro HD Wide

 - Brushless motor: Spitz 30 (BMI) 360 Watts (Max 480W),
 - propeller thin APC-E 12x6,
 - ESC: BMI #85505 C-45 (45-55A),
 - 4 servos Corona CS-929 MG (1.8 kg.cm, 12.5g),
 - Propulsion battery: Lipo 3S Turnigy Nanotech 3300mAh 11.1V,
 - Avionic battery: Lipo 3S Turnigy Nanotech 2200 mAh 11.1V,
 - UBec 5A, 5V for the Avionics (ArduPilotMega + Receiver),
 - Receiver: Multiplex RX9 DR with M-Link telemetry.

I am very grateful to the ArduPilot dev team and to all the contributors of the APM project:
Doug Weibel, Jose Julio, Jordi Munoz, Jason Short, Chris Anderson, HappyKillMore, Bill Premerlani, James Cohen, JB from rotorFX, Automatik, Fefenin, Peter Meister, Remzibi...
 
More infos at: http://diydrones.com/profile/JeanLouisNaudin

I went through some crashes on my Quad, and this is my solution.

It worked real well, I don't buy props that often now days!

I tried to reply to comments, but my reply link does not work or that may be me, who don't know how.

Anyway, to answer comment; Carbon fibre frame is 0.33 pound, flying time with it is 16 to 18 minutes with 5000 3s lipo

total weight on Quad is 3.42 pound excluding battery. flying time is gained by 4-6 minutes without carbon fibre frame (tape off to remove).

I have not thought about making a kit (It took me a lot of time + itchiness from carbon dust, headache from fume of epoxy). if there is demand, may be.

Quad is now very stable in NG code, PID tuning was very difficult though.

How I built is in my own comment on my blog along with some pictures.

Motor is e-flite 1020Kv, esc is e-flite 30 amp, prop is apc 12x6P electric. Video cam is 520CCD OSD & 5.4 Ghz Video Transmitter  from DPCAV, 12CH Futaba T12FGH.

here's some footage which highlights the features found on the

'Maveric', which was on display at the recent SOFIC 2011 event,

which was held in Tampa, FL. SOFLIC stands for "SpecialOperation

Forces Industry Concerence.

The Maveric has a flexible monolithic wing made from carbon fibre and

rip-stop nylon, allowing the wing to be bent completely around the fuselage.

The whole aircraft can be stored inside and deployed in less than two minutes

 from a 6-inch diameter tube that resembles a jumbo poster tube. Ripstop

 nylon is only used on part of the wing behind the leading edge. The rest of

the aircraft’s body (including part of the wing) is made from carbon fibre.