Wednesday, December 26, 2012

Forgot to rant about this

Last week, now they are using sock puppet accounts to try and make people look bad.  This is someone impersonating me on reddit:
"peabody124" in this case is not me.  Just someone with too much spare time trying to be a troll. I don't know who it is although phrases like "class A manipulator" sound like someone I know who matches a similar description.  The account was coincidentally created around the time PP started doing well, too.   These people are embarrassing themselves.  Then you have some (the same?) guy registering and setting the whois page to "James is a dick, ave" and some new vitriol now.

Seriously, I guess those who can't create anything themselves just feel the need to try and knock down others who can.  However, the good news is Phoenix is making great progress and extremely active.  We have a great team going and now the F3 port and Freedom and both working well.  I think Quanton should be out early next year too which is looking really promising.

Thursday, November 29, 2012

And it gets worse

So after being banned from IRC it gets even better.  Now my account and Kenn's account at OP have been hijacked.  I haven't had access since yesterday and suddenly I'm online:
Wow.  This new leadership really has zero integrity.

Wednesday, November 28, 2012

Oh OpenPilot. It's sad to watch you collapse.

Oh classic:

This was my favorite:
LOL.  Most of the devs have already left and we are definitely implementing our own ideas, but heck - Dave is even claiming he came up with "PhoenixPilot" and probably the idea of putting your pants on one leg at a time.  Coincidentally the domain disappeared last week :).  And of this demonstrates a complete lack of understanding of what the GPL means - there is nothing about it which requires one to actively push changes back upstream and all our work is published without any private repos.  The hypocrisy of that after being "strongly encouraged" to work in a private repo for the last year is astounding.  And of course the idea we are forking for commercial purposes instead of just to avoid the bullshit.  It's 99% likely Freedom will be CC-BY-SA unless we go try and go through Sparkfun or something.

While everyone else is trying to get work done, Dave of course wants to make things political and his hoard of drones starts talking shit.  The best part of it was Kenn had planned to make sure his work to merge it went upstream to OP since Dwillis doesn't know about all the drama in the background and doesn't deserve to have his work marginalized.  We predicted any response would lead to thread closure and sure enough...  Plus he was even pushing other miscellaneous fixes to the OP repo last week, but the facts interfere with the story so they should be ignored.

Meanwhile people are getting banned on IRC in the #openpilot channel, including all of BU and randomly George Tech (cause I guess, fuck them?).

Oh drama.  It's nice to be free of it.

On the up side we have a few more developers working with us now and things are really starting to roll.  Lots of cleanup on the ground and flight side and we should have quite a few boards integrated into the tree shortly.  Also, all the changes for Freedom have been tested and the next revision should be really slick.  The nav improvements and refactoring are coming along really well and I think there is a fair chance we can get that code running on both CC3D and Freedom as well as another board that will be entering the mix (more on that later).

Monday, November 19, 2012

Overo Comms!

Ah, finally found the problem with the Overo.  After hours and hours of tracking down an imaginary hardware bug due to the fact my scope sucks, it turned out to be an IRQ configuration.

So now I am just waiting for a new part to try out in the power circuit and then the design will be ready to spin a second version.

Freedom: Assembly and First Flight :)

Update: See this post for an example of utilizing the overo extension or this for examples of log analysis in python

So it was a long weekend but I got the boards assembled and flying.  Here are some photos.

Bottom with overo on it.  There are a few fixes right now ;-)

So far all the sensors are tested and working.  The modem works and gives a really nice dB level at the PipX side.  I need to do some head-to-head testing.  There are a few small mistakes that I managed to work around and will be easy to fix in another revision. 

The Overo works and boots (another small error in the supply lines needs some work but was an easy workaround).  The power supply _seems_ to be flaking out as I get FC reboots when powering via the servo lines.  If I power the 3.3V line directly there are no issues.  I think the inductor I used for the switcher is under spec'd so I've ordered another to test.  Luckily it should fit in relatively easily.  A more bothersome issue is the OVERO_CLK line is not getting through the level shifter right now - even after I cut the traces on the level shifter output side.  I need more sleep and it will probably be obvious.

Best part - it flew!  No issues, and flew quite well.  Much better than first RM flight, although those horrible big twitches are gone for RM too.


  • USB
  • MPU6000 - working (need to get noise levels)
  • MS5611 - working
  • HMC5883L - working, orientation dealt with
  • RFM22B - working, needs range testing
Not tested:
  • Current/voltage sensor
  • CAN transceiver
  • Reverse voltage protection (last thing :D)

Wednesday, November 7, 2012

New OP build

Since the new powers that be at OpenPilot would rather remove autotuning than simply fix the problem with it (and three weeks later still leave the fix rotting in review) here are builds that make sure you cannot fly with Autotune without enabling the module.  It also includes the very nice find from cyr which improves the estimation of level.


Friday, November 2, 2012

Routing done!

Ok so the board - OpenPilot Freedom - is finishing, pending final approval from a few people.  There were a few hold out connections that took some effort to route but nothing near any critical paths so I feel pretty good about it.  In the end the ground plane is completely uninterrupted and not used for any routing which was one of my main goals.

A few features:

  • 12 general purpose PWM pins (in or out), many of which also have ADC functionality.  Four are on a traditional servo header (for BEC and gimbal) and 8 are on a single row right angle header.
  • CAN transceiver for electrically robust add-ons, such as digitally connected ESCs
  • JST input pin capable of PPM, Spektrum and S.Bus
  • Two serial ports, one of which supports I2C
  • Reverse polarity protection on servo pins and serial inputs
  • Efficient switching supply provides operation from 3-17V
  • EMI filtering between radio and MCU
  • Built in radio (RFM22b) with a U.Fl. header to provide a low profile fit (without the servo header FC height is < 0.25")
  • Runs OpenPilot software

Top side 
Bottom side

Top routing layer

Tuesday, October 30, 2012

Board development update

Ok progress is being made.  I have the schematic essentially finished and the placement done.  I need to figure out how to convince Altium DRC not to complain about the components under the Overo.   Truth be told, I'm anxious about them.  However I've checked quite a few times on my existing board and everything seems clear.

So a few screenshots:

Friday, October 26, 2012

Board development

So I wanted a free alternative to some of the hardware I've been using for OP, and also wanted a few capabilities outside the normal boards so have been laying out a new one.  A first pass of floor planning is complete now and I need to start getting specific on the pin mappings to get the best routing.  Current schematic:

1. STM32F4
2. HMC5883 magnetometer
3. MS5611 pressure sensor
4. MPU6000 accel/gyro
5. RFM22b modem
6. Gumstix overo headers

Because with Cossacs we've seen power regulation is a critical issue and can negatively influence the attitude I'm trying a different approach to power.  Using a switching 5V supply that can take anything from 2-15V to feed a set of 3.3V regulators for the various components.  I do need to verify that this is appropriate for the Gumstix and that the 1.5A the chip I'm looking at is sufficient for the whole board.

Some additional features Kenz has requested are sufficient external ADC inputs for miscellaneous sensors so my target is the current/voltage sensors + 4 more (ideally shared with the PWM lines).

The headers for PWM input/output are something I want to critically evaluate.  At least for quads it's silly to dedicate so much board real estate to 100 mil headers.  Currently they fit on the board but I'm not sure I want them.  Similarly I'm not sure how much I care to keep PWM input honestly.  A PWM->PPM encoder can be used as a fall back.  I would probably prefer to dedicate this space to a CAN transceiver.

Finally if it were possible, I would love to get a CPLD/FPGA on the board to have some remaining flexibility to reconfigure things.

Updates to come.