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This $200 radio replaces your RC receiver and connects to your RC transmitter. Using the UHF band and higher power than regular RC gear, it's supposed to extend your range to miles. Mostly intended for FPV flying, but has clear application for UAV use, too. 

The manual explains how it works:

Basically, any 4-15 channel radio can work with this system, you just need to find
the PPM signal from the radio.
We can get the PPM signal from the trainer ports for Futaba （ Non-JR ） series
radios. Because the trainer port of JR just output 4-chans PPM signal, so we need to
find the PPM o utput from other places, normally we can get the PPM signal from the
pins of the RF connector

.
You can get all the definitions of the trainer port for most of the popular radios
here.
.
For the radios which have removable RF modules, we can get the PPM signal
from the pin of the RF connector

Available now from BevRC.

SSM has a fun physics questions over at RCG: why doesn't a tennis ball fall off his KK quad when he's flying?

Well, I wanted to return a stray tennis ball to some kids playing in the tennis courts at the local park.

So I pick up the ball and place it on top of my Quad. The ball is on an upside down plastic sandwich box (to protect the works), with a very slight indent in it, a couple of millimetres deep, so the ball rolls around and can fall off at the slightest bump.

I take off with the ball on board and fly over the court, expecting the ball to roll off at any second, and fall down to the kids. It doesn't. I rock the copter back and forth a bit. No change on the ball. I increase the strength of the rocking. The ball sticks there, like it's glued. I fly the copter around, turning, stopping and starting. No effect. I zoom the Quad up and down. To and fro. Frantically stopping, dipping suddenly, whamming it into turns. The ball doesn't budge. "What gives?", I think.

I bring the copter back to earth and place a second ball on top, with the first one. The two balls cannot both sit in the indent, and so they're now really unstable. If I carry the copter in my hand, it's hard to keep the balls on top - they fall off really easily.

So I fly the Quad with the two tennis balls on top to a position back over the court. And I do the rockin' and rollin' and shakin' thing all over again - the works. The balls just laugh at this and refuse to drop down to the kids.

In the end, the only way I can get the balls off the top of the copter, inside the tennis court, is to land the Quad. The balls fall off the instant the copter touches down, The boys are amazed.

So what gives? It's something to do with the fact that every time the copter dips in a certain direction, it accelerates in that direction? And this acceleration perfectly balances the inclination, so the ball/s stay centered and don't fall? Even with all that starting, stopping, turning and zooming?

An RQ-4 Global Hawk, a reconnaissance drone, will be used to help survey damage to towns and industrial facilities in Japan.

Now, development of an actuator for Marcy 1.  After all that static testing against gravity, the restoring force from the air wasn't enough to get the flap to straighten.  She just cocked up like a wing at 45 deg.

Since air exerts less force than gravity, maybe actuating the entire wing with some kind of spring as a restoring force isn't too crazy.


With Vika 1, we had low voltage transients, due to CPU usage at 40Mhz, sending the flight computer into reset.  Brown out voltage of 4.6 was making it reset.  Set it lower & it started working.


Did the same brown out voltage change to a Marcy 2 board we had since 2010 & it also started working.  That board was dead on arrival, last year.  Showed it during interviews & carried it around in luggage, not fearing it being destroyed by man handling, knowing it was dead.  Who knew it actually worked.  The Marcy spirit can't be destroyed.

The goal with the Marcy 2 board is now an autopilot for a cheap, 3 Ch copter, just to demo sonar.  Since these copters only go forwards & backwards, they basically have to constantly turn towards the waypoint & fly towards it.  Real workout for detecting heading.

Since they're extremely weight limited & have a limited number of flights before the brushed motors die, that means leaving it untouched. The best way into the controls is to bypass the receiver's IR signal with our own & use our own remote control.





There it is.  The $25 pink special everyone on RCGroups raves about.  $3 tax.



What's not discussed on RCGroups.



It should be passively stable because it's a counter rotater.

FUGGEDABOUTIT.  It doesn't have a gyro, so it spins & spins.  The controls have a serious lag.  It's no more dynamically stable than a Picco Z.  Forget about hovering over a waypoint.  The control lag kills any chance of substituting a gyro.

So what about letting it spin & using the tail rotor as a cyclic.  The pink copter has a lot more payload than the Picco Z.  It has a 150mAh battery.  To keep the demo under budget, we're back to a photodiode azimuth sensor.


The easiest sonar demo is a Sumo robot of some kind, that roves in a 10x10 ft area.  Even better, make it solar powered.

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=8992

Wow go now!!!

Status of Project:

Hardware Available and in public roadmap.

I wrote this post for me , for try to understand where this huge project are  going and for all our  developer , user and people that daily ask me a lot of things about It. I hope that this is a simple guide about what we're doing .

Multipilot32 (LYIF)

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

http://www.virtualrobotix.com/forum/topics/multipilot32-getting-started

http://www.virtualrobotix.com/profiles/blogs/multipilot-32-power-point

Status of availability:

• In stock 4 pcs.
• Next batch production will be available in second week of april.
• The product is available for developers, OEMs, students.
• The Product is available for end users.

If you want Buy the product contact : http://www.virtualrobotix.com/profile/ElisaLonga?xg_source=activity

Supported devices:

• DiyDrones Oilpan.
• PPM SUM Serial RADIO receiver same as used by Mikrokopter.
• Standard PWM ESC.

Upcoming device support:

• Standard multichannel PPM rc radio rx (need library implementation, HW is ok).
• DiyDrones GPS (need porting of library, HW and low level library is ok).
• DiyDrones Magnetometer (HW is ok, need low level i2c library and porting of apm library).
• LN IMU (work in progress).
• LN Navigation Expansion Board GPS, BARO.

Hardware in public roadmap:

• LN Multipilot32 IMU (work in Progress).
• LN Navigation Expansion Board GPS, BARO (work in progress).
• Next Revision of Multipilot32. RTF (work in progress).
• Pico CPU JTAG POD.

There are available two kind of enviroment one for entry level user supported by a branch of Arduino v 018 ide , called VRIde . Another is a complete professional Eclipse enviroment that support make project, upload firmware and debug using jtag functionality.

Available Ide :

VRIde rev 0.0.1

• simple user interface.
• Editing Code.
• Support C/C++ and wiring framework.
• fast editing and compile standard example.
• fast editing and compile standard library example.
• serial terminal interface for debugging.
• using external Demo Flash loader for update firmware to MP32.

Link: http://code.google.com/p/multipilot32/downloads/list

VROS : Eclipse + GCC Codesourcery.

• Professional Ide editor.
• Support Multiproject operation.
• Support C/C++ language.
• Editing makefile, linker script, asm code.
• Integrated make code: make clean , make all.
• Ready to use VROS 'C' template : ChibiOS/RT .
• using external Demo Flash loader for update firmware to MP32.

Link: http://code.google.com/p/multipilot32/source/browse/#svn%2Fbranches%2FRedfox74%2FChibiOS-VROS-Dist

Upcoming revision of ide: (working progress)

VRide rev 0.0.2

• Patch the interrupt vectortable to support high denisty micro.
• Update maple library for support of 4 serial interface , using also the serian interface connected to usb on oilpan.

VRide rev 0.0.3

• i2c support.
• flash bootloader by dfutil using usb.
  • link :http://code.google.com/p/multipilot32/source/browse/#svn%2Fbranches%2FRedfox74%2FVRide%2Fbootloader%20dfu

• support for Jtag uploader.
• support for Jtag debugger: step by step debug, variable watching in realtime.
• Vros C++ template and support of MP32 library.

Framework available status of development.

• Virtualrobotix branch of Xduino project for Multipilot32.
• Virtualrobotix branch of Maple library for Multipilot32.
  • link :http://code.google.com/p/multipilot32/source/browse/#svn%2Fbranches%2FRedfox74%2FVRide%2Fvride-library%253Fstate%253Dclosed
• Virtualrobotix MP32 VROS Library available for VRide and VROS.
• ChibiOS/RT with official support of Multipilot32.

Firmware available:

• Arducopter NG -> ArmFoxCopter 32.
  • Link : http://code.google.com/p/multipilot32/downloads/list
  • First Fligh link: http://www.virtualrobotix.com/profiles/blogs/multipilot-32-official

Upcoming Firmware:

• Arducopter Mega
• Ardupilot 2.0

Original Thread in the Forum : http://www.virtualrobotix.com/forum/topics/multipilot32-vride-and-vros

A digital control system model of the pixhawk quadrotor was constructed in scicoslab along with a continuous model of the quadrotor dynamics (the visual model is an arducopter). The user can input the guidance commands to the autopilot through sliders. As the video shows, the yaw response it not optimal, which also happens in the actual system. Using the mavsim Scicoslab toolbox (https://github.com/openmav/mavsim/) , the model can be simulated and then, once the system has been correctly identified, the dynamics can be linearized. The linear model of the system makes the problematic modes clear and aids in designing an improved controller.

Hey all, over the past two years I've spent a lot of time browsing the DIYdrones website, unfortunantley not really posting anything, but im ready to finally get back into it. The progress that has been made in these two years is absolutely astonishing, and I plan on getting wet real fast.

I'm now in college now, thank goodness, and i brought my interest in UAVs with me. I am studying Mechanical Engineering at Cooper Union in Manhattan, a small, full tuition paid university that has a pretty great engineering program, but lacks research. I worked my a$$ of this past semester and am finally comfortable with the workload thats required of me. I saw this as my chance to meld my college experience to what i actually want to do in the future, that is design and build UAVs. With that in mind I started the Unmanned Development Team this past semester. We have a pretty good pool of members, spanning a wide range of expertise (programming-through to-machinists) and we are looking to get something off the ground in the coming weeks.


To attract other possible members, and also in the interest of simplicity and limited airspace in the city, we started with Quads, while concurrently working on a the design of a fixed wing autonomous platform. The quad is much further along with a finalized design and construction underway.

Since the team is basically playing catch up with the industry right now, we saw the Ardupilot as a nice way to ease into things, and will be using the ArdupilotMega with IMU oilpan on both our initial quadrotor and fixed wing platform.

Frame-Solidworks Render:

The main aim of this design was to provide a modular platform that could accomplish a variety of present and future tasks. The center section is almost exclusively assembled with hexagonal standoffs which can be arranged in any way. There is a large amount of clearance on the landing gear to allow for the attachment of a variety of sensors, and there is a modular rail on top to provide the necessary mounting for other top positioned sensors and cameras.

The frame is primarily Aluminum and Garolite to keep weight down as much as possible maximizing payload capacity. The basis of the design for the center section plates comes from a Mikrokopter frame. The majority of the parts are CNCed and any remaining parts are hand milled in our student shop.

Completed Landing Gear:

I should be updating about the UDT regularly now, but if I stop, someone send me an email to tell me to get back on it.

Im looking forward to see how much will change in the coming two years...

Julian Alvarez

julian.6.alvarez@gmail.com

Mechanical Engineer 2014

Our team should have a website soon, among other things, so stay tuned.

The Arduino/Arducopter  is a notable project . Actually the ratio price/quality is very good.

But looking at the frame it is clear that some points can be improved: motor mounts, landing ski and GPS holder.

Working with a local company and using aluminum and laser technology we design and manufactured new parts for the Arducopter .

With this changes the new “silver Arducopter “  is more rigid, has a little bit less vibration and is more stable. The increase of weight is marginal.

And  Last but not least the Arducopter became a real UFO.

https://www.youtube.com/watch?v=ZIvta5oTpoM

Hi All

I worked together with LanyuHobby (RC airplane manufacture) to make a good platform for FPV/UAV flying.

The Fuselage is made in PVC to make it very strong (Blow moulded). Very good and strong for the beatings and landings our planes are getting.

I know it's nearly impossible to make everybody happy, but I think we found a good compromise. (Strong, able to take payload, good space for electronics inside fuselage, platform for autopilot under wing (CG), platform for Vtx behind prop.

Great Mr. Ali made a review of a handmade test version

It need a name, here's some names.

Any suggestions feel free:

Skyview
Skyexplorer
Dragon eye
SKYraptor
FPVraptor
CamEagle

The platform should be ready for sale next month, I think most vendors and maybe hobbyking will be selling the plane.

Price: same level as Skywalker.

(image from http://www.ngdc.noaa.gov/geomag/WMM/image.shtml)

Hi folks!

I decided to implement an on-board declination calculator based on geographic location and I'd love to get some feedback.  It takes up about 1400 flash bytes in total for a 3 degree declination error anywhere that people live (permanently - sorry Vostok!) and using a compass is reasonable.  It's not going to be flight tested until it stops raining here, so use at your own risk!  See the paper for more details :)

-John

Paper:

Lightweight%20Computation%20of%20the%20Earths%20Magnetic%20Field.pdf

APM Code - check under AP_GPS for AP_Declination_Lookup.*

ArduPilot.zip

LUT/IDW C# Calculator:

Geomag.zip

Footprint:

COMPASS_DECLINATION_LUT == DISABLED

113268 bytes, Free RAM: 1351, using 2061 bytes of memory

COMPASS_DECLINATION_LUT == ENABLED, COMPASS_DECLINATION_LUT_ACCURACY_LEVEL == 0

Accuracy:
Scalable with table size

Table size: 89 entries (COMPASS_DECLINATION_LUT_ACCURACY_LEVEL == 0)
-------------------------------
Error   0 percentile: 0

Error  10 percentile: 0.1098926

Error  20 percentile: 0.2223369

Error  30 percentile: 0.3377705

Error  40 percentile: 0.4542923

Error  50 percentile: 0.5770731

Error  60 percentile: 0.7134132

Error  70 percentile: 0.8671622

Error  80 percentile: 1.072514

Error  90 percentile: 1.401104

Error  91 percentile: 1.447367

Error  92 percentile: 1.495352

Error  93 percentile: 1.551685

Error  94 percentile: 1.611044

Error  95 percentile: 1.676226

Error  96 percentile: 1.764013

Error  97 percentile: 1.864101

Error  98 percentile: 1.988347

Error  99 percentile: 2.208701

More pictures from the DIY Drones factory in San Diego. I mentioned before how important testing and QA is. The above picture shows how it's done: each product has a dedicated test jig, with spring-mounted pogo pins and a special version of the product board running test code.

The board to be tested is pressed on top of the jig, and the pins fit into the board's holes to make an electrical contact. Then the special test version of the product runs a series of diagnostic tests on the board. If it passes, it's shipped out. If it fails, it's thrown out or sent to engineering to figure out what's wrong.  

We need a different test jig for EVERY product. So in a sense, we have to design every product twice: once for the product itself and another design for the product that will test the product. Another thing to keep in mind if you're thinking about getting into the electronics business. It's harder than it looks!

Here's what the jigs look like from the side:

For fun, here are a few more shots from the factory:

Here's here the foam peanuts that your board are packed in come from!

And here's that high-precision scale that can count how many screws we've put in a bag, so we always get the right number.

ore

Good article from O'Reilly Radar. It's worth reading it all, but here's the nut:

The core issue is that GPS technology has been built into many crucial infrastructure applications, from transportation systems to power grids, and in many cases there is no fallback option should the GPS signals suddenly become unavailable. GPS has many advantages, but it is not particularly secure or robust in terms of interference, due to its relatively weak signal strength. GPS hasn't failed in any major way yet, but concerns are growing with recent reports of strong solar storms that have the potential to disrupt GPS satellites, and a troubling, growing black market of GPS-jamming devices.

The heart of the operation: the pick and place machine

A lot has changed since my last photo tour of the DIY Drones San Diego factory. We've moved next door to space more than twice as large and added all sort of new pro equipment including everything from a big new reflow oven to a special high-precision scale that allows us to count the exact number of parts in a kit by weight, so we never miss one.

It's easy to make a few PCBs or even send them out to a fab to have them made, and a lot of people getting into electronics start that way. But once you get beyond a few dozen boards to hundreds and then thousands, you need your own factory to ensure that the products are manufactured and tested right. For every product there must be a test jig and test code to check it and you need as many people in customer and technical support as there are in production.

DIY Drones now has a dozen employees doing everything from new product development to customer support. Here are pictures of many of them and their work stations:

The pick and place doing its magic!

Arturo applying solder paste

Close-up of the use of a paste stencil

Anette and Mireya in shipping

Cindy testing

Changing the feeders for a different board

Final hand-placement of components by Brian

Operations manager Lorenzo Lopez. He's The MAN!

Amateurs break their PCBs along the score lines. Bad idea (it can cause cracks)! Pros use a PCB cutter.

Rebecca does the accounting

The reflow oven!

Here's the oven's control panel

Samuel, one of the design engineers, shows off a glimpse of a new OSD board that's in development. Shhh!

Anette at a shipping station

Shipping supplies!

Yvett in customer service

This is the new folding frame Project I am working on.

Can anyone tell me if it´s possible to control the eight counter rotating motors with ACM.

By popular demand, ArduPilot Mega is now available as an all-in-one kit for $250. It includes everything you need for a functioning autopilot with GPS, even including RC cables.

We'll soon be offering wireless telemetry options for this, too, along with a ArduCopter version that comes with a magnetometer. A pre-soldered version of APM will also be available in a month or so, once we put in place a rock-solid testing process.

In the meantime, you can buy APM pre-soldered with code loaded and tested from uDrones for $349.

Having got to the point where I have engineered a multi-rotor flying camera mount that works to a very high level of stabilization (sub .05 deg.) I need to complete the puzzle with some help in designing some boards to compliment the APM system. Then the community at large can buy off the shelf, here at DIYDrones, the right components to do the job properly.

I am not an EE so I probably don't know what I am talking about but I do know the aerial camera mount business inside out. As I see it, the task is this. Camera mounts need to have a very different approach to that of stabilizing a multi-rotor copter. It is a lot simpler for a start. 300/500 deg/sec gyros typically output 2mv./ deg/sec but Invensense for example make gyros specifically for the job of stabilizing camera IS lenses and camera platforms the IDG 1150 for example is a 20 deg/sec. gyro that can output 50 mv/deg/sec. other gyros are available that have dual output that amplify the signal by a factor of 4, but as I see it this only amplifies the critical area which is at the very initial point of movement - noise. Sub .00? is normally only achievable with mil. spec. fiber optic gyros which are way beyond affordability in our case, but as Mems systems have come along in leaps and bounds recently. I believe we can do this to create top professional results at very little cost. Such high sensitivity modules would only work in a vibration free environment and this problem has been addressed and a complete solution is now available. Along the way a multi-rotor craft has been developed that not only is aerodynamically better than conventional designs but it uses materials that float on water and give better crash resistance and weight. Such a craft can be made using cheap materials that are freely available and can be fabricated with simple tools.

The 5/6 axis system explained. We all know that it is only possible to move a camera thro 3 axis of movement - pan, tilt and roll. the typical high end gyroball device uses the inner axis principle to fine tune the high accuracy movements.

Our model can create that outer axis and with a just little more work can be made to integrate perfectly with an inner axis system. The inner axis can be a simple 2 axis module device or a more complex 3 axis. The 2 axis module would be attached to the camera base plate and would have pwm in /out and utilize 2 axis acc. to reference gravity. The 3rd axis again a stand alone module would be in the Z axis (Pan) and integrate with the FC's mag.

Once this has been achieved we can step into the really exiting stage which is to create a total system where the operator simply fly's the camera and the copter follows the camera's desired track. it will use optic flow technology to look at the cameras LCD and augment stabilization and create an auto object tracker. WOW.

My prototypes are made using components such as heading lock gyros that have been modified to accept high sensitivity gyros but these are created as simple test bed components and need a lot of sorting out  before they could be used commercially.

I have only just started with APM so do excuse my ignorance if I made false assumptions at any time.

Most of my model development was done with a simple KK FC so as to create a reliable benchmark. I later moved onto the MK system which did not cut the mustard. It became known as the MK fireworks kit as ESC's and power distribution boards would burst into flames for no apparent reason and then there was the death roll gyro problem where hundreds of duff FC boards were sold to the unsuspecting masses. It would try to transit cumula granite resulting in the spectacular drop kick bang smash. They were the days! Onwards and upwards as they say. Interested anybody?