Ardupilot roll functional flow diagram

I'm installing Ardupilot in the 6 foot wingspan electric Telemaster. As this is a significantly different airplane than the Easy Star I want to proceed slowly and carefully. If I can I am going to adjust and confirm PID settings, etc, one function (roll, climb and speed) at a time, starting with roll. I decided I needed to have a good idea how the roll software is implemented in Jordi's and Chris' marvellous software. So I embarked on developing the functional flow diagram shown here. It is based on V2.2.3roll_flow_chart.pdfI'm a noobie at this so I don't claim it is 100% accurate although I think it is close. Doing this has been a good education for me but I wonder if it is useful to others. I would be interested in Ardupilot enthusiasts' comments, including suggestions for corrections and/or improvements.By the way, the term "heading" is used incorrectly in the software. In navigation parlance, heading is the direction of the airplane's fore and aft axis in relation to a fixed reference. The reference could be magnetic north if the airplane has a compass or true north if it has some kind of gyro-based measurement device (AHARS or IMU). Ardupilot as it is presently configured has no heading measurement device so it does not know what it's heading is. Where heading is referred to, it is really course over the ground that is being talked about. No big isssue now, but will become so when Ardupilot adds a heading reference in the future, which I think is inevitable.
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  • sells and distributes the arf version. I got mine from a Canadian distributor of Hobby Lobby products. I don't have any other source for you
  • Fred,

    Thanks for your reply. I'm sold on the Telemaster but I can't seem to find an ARF/RTF anywhere in the US !!! its probably our bad luck ! Any chance you may know of someone that has one for sale ? I am in the chicago/iowa region.

    Thanks much for your help.
  • Hi
    Unfortunately I had a serious accident with my Telemaster. While troubleshooting an IR stabilization issue, it ended up in a vertical dive. Using all my beginner skills I pulled out too hard and the wings folded. It is now a major rebuild project. So my test program is on hold.

    I think it is a very good platform for the reasons you point out and I guess could meet your requirements. With my payload it acts almost like a glider so I think it will easily tolerate the extra weight you will have. Because I only have a small station wagon for transportation I did design the aircraft as 2 piece wing. I am also not a fan of elastic wing hold-downs so I modified the wing so the trailing edge is bolted down and the leading edge is locked with protruding dowels to the forward bulkhead.

    Good luck with your project
  • Fred,

    I am hoping that the Electro Telemaster would fill our needs given its low wing loading, ample fuselage space and a decent size wing area. We are looking to carry 1 lb of payload and fly for 30 minutes.

    What have your experiences been with this airplane ?

    Also, from a transportability standpoint , is the wing a 1 piece or a 2 piece wing ?
  • Chris

    Perhaps you're right. Rather than identify the functions as notes the way I have done, I could maybe block diagram the functions and the connections amongst them. I'll have a look at it. I do like the software flow diagrams for showing the PID loops, however, so maybe having both is an answer
  • I get more from the flow chart than I do from the code. I am a licensed pilot and an instrumentation tech so it just makes better sense to me as is. I would like to add a feed-forward loop to change the elevator aileron mix loop in the code to add more up in a high speed turn and less at lower speeds but dont know enough about the coding. I would like to have my F-18 fly chase plane for my SR-71. I am sure with that task tighter reigns are needed for the flight pattern. If there is not enough program slices to go-around I would be willing to add another ardupilot board to do tracking/waypoint updates and pattern management. I am trying hard to fallow this project daily ever since my first post. I want to learn more about the programing end. Thanks for sharing your work.
  • 3D Robotics
    Hi Fred,

    I'm a noob at software flow diagrams, too, so I don't know how useful this one is. Maybe we should start with a higher-level block diagram?
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