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Parallax Propeller as an Autopilot - Bench test

Posted by paul hubner on October 16, 2007 at 9:02am
I've been working on and off toward creating an autopilot using the Parallax Propeller microprocessor and finally have something to show for it. My autopilot has the following features:
  • Return to starting point when pilot looses the plane
OK. It's not a very large feature set yet, but it is both a personally important important one, and it provides the underpinnings for a much greater capability. In actuality, the platform it already supports these:
  • GPS input and parsing based on several NMEA codes
  • Waypoint storage (one for now)
  • SD card support
  • Radio control receiver interface
  • Servo control
  • Video output of any GPS and microprocessor values
  • As a separate unit, 2.4Ghz video downlinking.

And I plan to add the following to the mix:
  • Video overlay on the downlink
  • Google Earth Integration for setting routes (via KML file read/write)
  • Pan/tilt/snap camera control integration

I've added a bench test video of the alpha system for your viewing pleasure. Feel free to copy any code you like from my library if you are using the Propeller. When I get further along, I'll officially open source it. Anyone want to code?

Everything else in is in software. Lastly, I really like this platform. If you notice the hardware in my video, I only added ONE resistor on the board on the servo interface. I know - the SD card has a few on its daughterboard, and so does my LED plugin, but these boards are optional. so this is really really easy for me to work with.

I hope to flight test this weekend, but I may take the family for a drive south to the Maker Faire in Austin.

Please comment!
Paul

Code at: www.hubner.net under "SPIN code"
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Comments

  • 3D Robotics
    Chris Anderson November 10, 2007 at 10:36pm
    Paul,

    I assume you know that the Atto Pilot that Icebear is beta testing is based on a Propeller chip...
  • Ben Levitt November 10, 2007 at 5:53pm
    Paul,

    Have you thought about using IR sensors and another propeller cog to try to do stabilization internally, to avoid the need for the CDP4?

    It would be great to cut down on the number of components required, but I'm not sure how complex the code would have to be to make it robust enough to not do stupid things like flip upside down when it gets dark, or go into a roll when passing by a grove of trees...
  • paul hubner October 31, 2007 at 8:59pm
    T-Rex,

    I built my SD storage card out of parts from Mouser.com. Its a standard SD card reader, 4 resistors, and a few pins on a home etched board. Its pretty rough, but it works!
    Paul
  • T-Rex October 31, 2007 at 6:22pm
    Paul, what hardware are you using to interface the SD card with your Propeller proto board? Seems like SD could be such a nice alternative to EEPROM storage.
  • paul hubner October 19, 2007 at 7:48am
    Chris,

    I do have an FMA copilot CDP4 to stabilize the plane - seems to work nicely.

    Flight testing will have to wait for a little funding as I (abbr. version) vaporized my external GPS. Let's leave this story-for-another-day knowing that a GPS, momentum and concrete are not a good mix.

    Paul





    thankls,
  • 3D Robotics
    Chris Anderson October 17, 2007 at 4:15pm
    Paul,

    That's really impressive. One of the nice things about the Propeller chip is its video output capability, which makes telemetry in the video stream pretty easy (and saves money on outboard video boards). Are you using the FMA Co-pilot for stabalization?
This reply was deleted.