Replies

        • Without knowing the specifics of those components, I think the logical choice would be as you describe.  You can always plug it in and check the radio cali screen to see what's what.

  • Ok, thanks Leonard.

    I'll try to be more patient considering hard winter has set in. It isn't bad flying, but should be more stable in windy conditions as big as it is. I was seriously considering getting out of the co-axial copter business altogether, but will wait for the changes in AT.

  • Why won't the 'Lock Pitch and Roll Values' box stay unchecked after writing the parameters? After each AT, the box is checked and all the Pitch/Roll values are the same.

    Today I took the laptop with me, unchecked the box, saved it, did AT, refreshed the parameters and there it was again; box checked and Pitch/Roll values still identical.

    Thanks.

    • Developer

      Hi DG,

      Looks like your autotune isn't finishing. Do you have a log?

      • See attached. I don't recall it necessary to unplug the power after disarming, turning AT off. Maybe that is the problem?

        If you see anything else unusual feel free to critique. And pay no attention to the battery FS violation....at least it worked as instructed. :)

        375.BIN

        • Developer

          Hi DG,

          Could you tell us about your frame and maybe add a couple of photos.

          Your autotune is maxing out on each axis and that is why your values aren't changing and are the same. I suspect that mission planner is then seeing that they are all the same and enabling the same values box.

          Your copter is an interesting case as I haven't seen a copter got to maximum on all values.

          • It is a Sky Hero Spy 750

            KDE 2814XF-515 motors

            HobbyWing XRotor ESC (latest AT was done with default intermediate timing)

            MS 4s 10000mah 10c battery secured full length with velcro and two straps

            CSGshop Neo-M8N GPS/compass

            3DR Pixhawk FC

            3DR Telemetry

            Frsky X6R rx

            14.5.5 Gemfan TM style props on top

            15x5.5 Tarot TM style props on bottom

            The ESC's are mounted in the arms and are a snug fit.

            5efBTMK.jpgWithout canopy and before Neo-M8N GPS installed. Pixhawk is mounted using one layer of Kyosho gel tape on top of four plexiglass standoffs (to provide access for wiring). The vibration levels seemed ok so didn't mess with it.

            AqzeIM9.pngIf you look back a few posts, I had problems with yaw wonder and instability with Y6B settings which you suggested changing the Loiter and Yaw parameters and also the Rate for pitch and roll in order to be good enough to do AT. The PWM from top to bottom motors were not correlated, but after using 1" smaller props on top it worked much better so I returned the Loiter/Yaw parameters back to default before doing the last AT.

            The copter takes off perfectly straight and can hover inches above the ground. I still question issues with the ESC's however (this is the fourth one), if only slightly, but the HobbyWings seem better than the others; have not tried high timing on all 6 yet, experimented with top props on high. I'm really beginning to think KDE motors should be used with KDE ESC's.

            • Here is the power area; homemade PDB using .040" copper plates with bullet connecters soldered on them and housed in a 3d printed "coffin". I tried to keep it simple and tidy to avoid the chaotic spaghetti bowl my projects usually end up as. The 12 awg wires have since been replaced with 14.

              krjEpwD.jpg

              • Leonard,

                   There is a lot of "dirty air" between the props. I've discussed this with someone that has a lot of experience with Y6 designs and he says the closer the top/bottom props are to each other, the less efficient they are,  the performance degrades and the copter can behave oddly especially in more windy conditions. 

                Right now there is about 3" between the motor prop surfaces. He says with this size and weight copter, it should much more than that, like 4" minimum.

                What do you think?

                • Developer

                  Hi DG,

                  The coaxial prop set up is very complicated. I don't think anybody realisticly tell you that 4" is better than 3". There are simply too many variables.

                  I can confirm that the lower prop is working harder than the upper prop but when I tried a bunch of combinations for the 3dr coaxial designs there was no clear trend. During this process I read all the research literature I could fine and discussed this will many people.

                  What I found is the performance varied greatly depending on the diameter, pitch, manufacture, model, motor kv, airframe mass. There were no clear trends that made it easy to predict what the best combination would be. However, there were some combinations that performed much worse. So provided you avoid the bad combinations, issues like ease of maintenance, availability, and cost are probably the deciding factor.

                  When I did my work on the 3dr Y6 I was looking for combinations that maximised the flight time, minimised the difference in pwm outputs between the upper and lower motors (this ensures maximum lift at full throttle), and resulted in as even motor and esc temperatures as possible.

                  Sorry I asked to see your copter again. I loose track of who has what airframe. As I said last time, nice copter :)

This reply was deleted.

Activity

DIY Robocars via Twitter
RT @a1k0n: @DanielChiaJH @diyrobocars @circuitlaunch Here's my car's view of that race. About 8.4 second lap times for laps 2 and 3... both…
yesterday
DIY Robocars via Twitter
RT @DanielChiaJH: Great racing against @a1k0n today at @diyrobocars! Pretty cool to both break sun-9s at the track today I think I got very…
Sunday
DIY Robocars via Twitter
Broadcasting the @circuitlaunch race live now at https://m.twitch.tv/diyrobocars Races begin around 2:00pm PT
Saturday
DIY Robocars via Twitter
RT @a1k0n: ran a huge number of hyperparameter tuning experiments yesterday; now I can train a new policy, far with better quality, in 15 m…
Saturday
DIY Robocars via Twitter
RT @a1k0n: Did I get rid of hand-tuned parameters? Yes. Am I still hand-tuning more parameters? Also yes. I have a few knobs to address the…
Sep 26
DIY Robocars via Twitter
RT @a1k0n: I'm not going to spoil it, but (after charging the battery) this works way better than it has any right to. The car is now faste…
Sep 26
DIY Robocars via Twitter
RT @a1k0n: Decided to just see what happens if I run the sim-trained neural net on the car, with some safety rails around max throttle slew…
Sep 26
DIY Robocars via Twitter
Sep 24
DIY Robocars via Twitter
RT @SmallpixelCar: @a1k0n @diyrobocars I learned from this. This is my speed profile. Looks like I am too conservative on the right side of…
Sep 24
DIY Robocars via Twitter
RT @a1k0n: @SmallpixelCar @diyrobocars Dot color is speed; brighter is faster. Yeah, it has less room to explore in the tighter part, and t…
Sep 24
DIY Robocars via Twitter
RT @a1k0n: I'm gonna try to do proper offline reinforcement learning for @diyrobocars and throw away all my manual parameter tuning for the…
Sep 23
DIY Robocars via Twitter
RT @circuitlaunch: DIY Robocars & Brazilian BBQ - Sat 10/1. Our track combines hairpin curves with an intersection for max danger. Take tha…
Sep 22
DIY Robocars via Twitter
RT @SmallpixelCar: Had an great test today on @RAMS_RC_Club track. However the car starts to drift at 40mph. Some experts recommended to ch…
Sep 11
DIY Robocars via Twitter
RT @gclue_akira: 世界最速 チームtamiyaのaiカー https://t.co/1Qq2zOeftG
Sep 10
DIY Robocars via Twitter
RT @DanielChiaJH: Always a good time working on my @diyrobocars car at @circuitlaunch. Still got some work to do if I’m to beat @a1k0n howe…
Sep 10
DIY Robocars via Twitter
RT @SmallpixelCar: My new speed profile for @RAMS_RC_Club track https://t.co/RtLb7TcgIJ
Sep 10
More…