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For those intrested in having one of these low cost radios here is your chance! 

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I would like to "formally" announce two open source projects related to optical flow / programmable vision sensors. These are based on some of the optical flow techniques developed at Centeye, but in the spirit of "open source" are meant to be hacked/modified/copied any way a user deems fit. In both cases, the source code has been opened up under a modified FreeBSD license, while the board design has been released under a Creative Commons Attribution-ShareAlike license, the same license that applies to the Arduino boards.

The first project is the CYE8 sensor, an optical flow sensor based on an Atmel ATmega644 (possibly to be replaced by an ATmega1284) 8-bit processor, and using a Faraya64plus sensor head. (A "sensor head" is a vision chip wire bonded to a 9mm x 9mm PCB with a board to board connector on the other side.) We fabricated our first two iterations last year (the first one described here), and are now readying the third iteration this month.

The hardware of the second project was introduced in a recent blog post and is based on the Sparkfun Arduino Pro Mini platform (which uses a similar but smaller Atmel microcontroller) and comprises a simple shield board that interfaces the Arduino with a sensor head. Currently we have used only a FarayaSmall sensor head, but this board will support other chips as well.

At the current time, these projects are hosted on another open Ning network Embedded Eye, since we are trying to capture a broad set of applications beyond drones. If these projects take off, we can set up Huddle spaces accessible across both Ning networks, or move the project elsewhere. (I'll take suggestions- I'm still learning about how to do projects like this.) The CYE8 project is located here and the Arduino-based project is located here. These forum pages include initial board designs and source codes.

Based on interest, we will likely also launch projects built around an Atmel AVR32 processor (faster than the AVR8's) and/or an XMOS quad-core processor (if you have real need for speed).

One common theme of these two projects (which has strengths and weaknesses) is that they utilize vision / image sensor chips designed by Centeye. (This is not a requirement of the license- it is just how they were designed.) The strengths are that since we designed the vision chips, we can probably reveal as many details of the inner workings of these chips as we want. We all have heard complaints of chip manufacturers being too vague about what is inside, so I hope that this is a welcome change. The weakness is that we basically have to burn new wafers every time we want more sensors, so they are not as available as, say, a part from Digikey.

We are actually going to start a new run of silicon soon with the intent of increasing manufacturing quantity. It is tempting to use this as an opportunity to explore semi-open chips designs. I'd be happy to share a (virtual/real) beer with anyone interested in discussing (whether here, at EE, or directly) the various issues associated with the design and manufacture of chips of this type.

I look forward to speaking with everyone soon!

Geof

I've now gone around one full circle on the UAV wheel: I built her, flew her, and crashed her. It has been great fun so far and I can't wait to get in the air again. Before I do, however, I thought I would write something so that other beginners could learn from my mistakes.

Anticipation and Assembly

I decided sometime last April to buy an ArduCopter spent several months in breathless anticipation. I got home from Antarctica early this January to find the package had arrived and feverishly started building. A few little issues I encountered during construction:

- When connecting the ESCs to the power distribution board, the wiki guide advised me to solder them directly on. My ESCs had Deans connectors on them, so I chopped them off and soldered them on per the wiki instructions. Only later did I find the electronics assembly PDF, which advised soldering female deans connectors to the power board so that the ESCs could be disconnected. After finishing the copter, I found four female deans connectors in my kit which were for this purpose and wished I had followed the PDF rather than the wiki, so that I would have easily removable ESCs.

- The method for mounting the ESCs and dealing with the motor wires is unclear in the wiki instructions. This is probably because there are so many ways to do it, and also different types of arms. In the end, I velcroed my ESCs to the curved plastic supports of the protective dome, braided my motor wires, and wrapped them around the quad arms to take up the slack. In theory I guess the motor wires could go through the inside of the arms, but the arms that came with my kit had "half holes" i.e. they only have the slots for the wires on one side of each arm. Also, the slits for wire insertion are at the very end of the rods, so the motors mount right on top of the slits and it seems difficult to get the wires into the slits as the plastic motor screws are in the way. Not sure how this is supposed to work, it seems like maybe the "wires inside the arms" idea was abandoned during the design at some point.

- I cranked down too hard on one of the screws for the motor mounts, and cracked one of the thin clear plastic pieces below the motor and arm. This comes back to haunt me later in this blog entry!

- I forgot to solder 5 of the pins on the 6-pin header that connects the ArduPilot with the ArdIMU. This had the surprising result that the ArdIMU worked, but only in CLI mode. I was quite embarrassed when Sebastian on the forum suggested I check my soldering and it became clear why the ArdIMU was not initializing in normal mode!

First and second "flights"

Once I'd figured out my new Turnigy 9x and finished calibrations, I headed out to a nearby field with a couple of friends. After a good deal of testing I gritted my teeth and eased up the throttle. The hum whirred into a buzz and then... two of the propellers popped off, launched high into the air!

It reminded me of the Gemini test scenes in the movie The Right Stuff. I scratched my head for a while and eventually concluded that, unlike the motor mount screws, you really need to crank down on the propeller attachment chuck.

Props securely fastened, I tried again. This time, the copter got 3m up into the air and began to fly away from me quite quickly. Thinking I would bring it down and consider a recalibration, I eased off on the throttle. Cindi Lou (that's the copter's name)  descended a few feet while still drifting away from me and then promptly flipped over at a little under 1m from the ground and attacked the grass! My friends tried to contain their laughter as I inspected the damage, which was disabling but not catastrophic: cracks in the top and bottom plastic sections of the forward motor mount. Here are a few photos of the damage, and a video of both attempts.

Recovery

 Eager to get back in the air, I ordered the $30 crash kit from the Fah Pah store. I would have preferred to order from DiyDrones (since they're in the US, not Thailand) but it seems they only sell full replacement frames and replacement arms. Not content to wait for delivery, I picked up some plastic repair epoxy from Ace Hardware and set about mending the motor mount. It looks fairly solid, but I'm not sure if I would be jeopardizing the rest the Cindi Lou should I attempt to fly on the repaired mount. My impatience to fly again is competing with my better judgment here...

Lessons learned

I'm not certain whether the crashed was caused by my poor construction job, or my poor piloting. I wonder if the pre-existing crack in the bottom motor mount section contributed to the crash. Either way, the crack in the top section was certainly caused on impact with the ground. One take-away message is to tighten the propeller chucks hard, but not the motor mount screws. Perhaps a more important one is to make sure the copter's horizontal motion has stopped entirely before attempting to land!

Entries for Sparkfun's 2011 Autonomous Vehicle Competition are now open. The event is on April 23rd in Boulder, Colorado at Sparkfun HQ. This is the third year of the AVC. In the first year a DIY Drones team came in first, in the second year we (Doug Weibel!) came in second. Let's not make this an arithmetic pattern!

Here are the new rules for aircraft. Looks like precision landings, low altitude, and autonomous (no hands) take-offs will be winning tactics. Hello, quadcopters!

Air Vehicle Rules:

• Must also go around all four exterior walls of the building.
• The lap time will be calculated from when the Judge says 'Go' to when the plane comes to a halt in the back parking lot. A landing (autonomous or manned) outside the rear parking lot will disqualify the lap time.
• Weather permitting, balloons on long freaking strings will be launched from the four corners of the building. The balloons will serve as guides for the judges/competitors as to the location of the corners/walls of which the non-ground vehicles must circumnavigate.
• Regardless of weather/wind, the vehicles must clear the four exterior walls/corners of the building (not the balloons), verification of clearing the vertical plane will be up to the four line judges.
• Autonomous take off is worth a 10 second reduction from raw time.
• Wheel carriages are allowed for aircraft that don't have their own wheels. Human assisted take-off (throwing a plane) is not considered autonomous.
• Autonomous landing (coming to a halt) within the indicated box is worth a 30 second reduction in time
• Within SFE back lot parking area (not in the box, but must be on our blacktop) gets a 10 second reduction in raw time.
• Time reductions will also be awarded for the three planes that have the lowest peak altitude. To calculate this altitude, SFE will have devices available (likely made up of DEV-09530, SEN-09694 and PRT-00731, came in at 6.71g), weighing no more that 15 grams, to be placed on the UAV by the Judge via double-sided tape on the day of the race. A 60 second reduction goes to the lowest peak, 30 seconds for the second lowest, and 15 seconds for the third lowest. Competitors may also opt not to carry these devices and forego the possibility of a reduced time.

Preventative measures needed before "neighborhood nutjob mounts a weapon onto his personal drone" . . . Attack of the Personal Drones

Info for the Landkamp 2011 event

I was not able to find anything about this ont he blog so far, but as I was browsing Hackaday this morning, I saw a link to the Vicacopter site. http://vicacopter.com/vika1.php

It looks very similar to the ArduCopter, but seems to only have 2 accelerometers rather than the three that we use, so with the magnetometers, it has 8 DoF. Other than that, details look pretty scare.

Hackaday have film of it doing some skywriting on their post: http://hackaday.com/2011/01/17/tri-rotor-helicopter-with-full-autopilot/

QRO v5: Maiden flight with a GoPro HD wide

Hello,
You will find below my maiden flight successfully done with my quadcopter (QRO v5) with a GoPro HD Wide camera. This video has been done on january 16, 2011, early in the morning.

My setup is:

A hands made Quadcopter (QRO v5) with a Minsoo Kim's KKmulticopter (Blue board version).
Firmware: XXcontroler_KR_1_1a (JLN updated)
4 brusless Dual Sky XM2822CA - 1450 KV - 100W
4 ESC DualSky 12A
4 propellers (X-UFO props modified)
Lipo: 3S 2500 mAh

Regards,
Jean-Louis

After the ArduCopter build. I decided to build a small quad for fun. And release it to the public. You can use my design to make your own or change my design to make your own mini quad.

The picture is just a sketch. I didn't finished the design. So it just a screenshot.

It is 1:1 size that you can easily get the idea how big it is.

I used the Adobe illustrator to design the frame. The file can be send to the Ponoko.com to make frame (Acrylic 3.0mm or thicker).

The frame will have 2 or 3 layers. The top layer will used to guide APM, receiver, Moter, ESC, wire and etc. The bottom layer will be the battery holder. Motor arm and holder will be integrated as one layer.

Parts:

1. Frame: 26.5cm (10.4 inches) from motor to motor (Ponoko.com price will be around $50 or less)

2. Motors: C1822 Micro brushless Outrunner 2100kv (14g)

    http://www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=5378

3. Propeller: GWS EP Propeller (DD-4025 102x64mm) (6pcs/set)
    http://www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=10040

4. ESC: TURNIGY Plush 10amp 9gram Speed Controller
    http://www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=4204

5. Battery: 2S or 3S under 1800mah are recommended

6. Core: APM + Oilpan

7. Optional: GPS, Magnetometer and Sonal

So you bought the EM-406, the EB-85, the uBlox-4, & the helical uBlox-5.  Now you're wondering what to do with all the GPS modules everyone hyped but which turned out to be utter trash everyone was trying to get rid of.  Time to make a GPS guided speedometer.


It starts with our 1st & only answering machine in the days when cell phones were novelties. It got us through grad school. Really well designed for the available technology. It was time to put it down for recycled components.







All that tearing for a crummy LED panel.



This LED panel has 2 grounds & 1 pin for each segment.  It goes up to 1.9V before getting too bright.  The digit is selected by the ground, so it has to alternate.



Went with the obsolete EB-85.



There it is.  All it does is show current velocity. No logging or other information. Could be done with a phone much more easily but this is free & fills the exact, immediate need as fast as possible.

With only 2 digits, it shows speed * 10 below 10mph & integer speed up to 99mph.  Didn't have a display with a decimal point in the middle.

If we could afford a better display, the next most important feature would be elapsed distance.















If only MMY mobile could go back in time like the real thing.

Now the video of GPS guided speedometer in action.  The velocity lags if direction changes.  It really lags when walking from a complete stop.   It's completely unreadable in daylight but useful at night.

This is a design I made my self on CAD.

This design has taken me about 3 months of drawing, and editing to get this awesome design!

I have a few more edits to make to the design before I will share it, mostly just to make asembly easier, nothing major.

This is the death of my beloved proto-type! =[

The crash was completly pilot error.. I wanted to test how goo the stabilize was by performing an aerobatic manuver, and turning on the stabilize mid trick..

Sadly while planning to do a loop, I turned off the stabilize mode, and a cross wing picked up the wing... (Alt. 50ft, Velocity 40mph?)... not a great idea.. haha

Great news is almost all of the electronics lived!

I am only out a Ublox GPS, 1800mah lipo, and an airframe...

What I've learned out of this crash:

1. Im a horrible pilot with out a APM helping me.. haha
2. I should probly protect my GPS, and battery better just in case...
3. Never underestamate deprom.. I may be missing a nose, and fusaloge, but the wing, and tail was still in good shape!
4. Never put anything before God! (I slept in, and missed church...)

This video is not very exciting, but documents a working model!

This is my first flight with my prototype!

Only in Rc mode/Stabilize!