Servo/Rudder Problem

Discussion in 'Electrical & Radio' started by tgalx3, Jan 20, 2010.

  1. tgalx3

    tgalx3 Well-Known Member

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    I have hooked up the servo and rudder. Everything works fine, although the rudders arent making as sharp of turn as I remembered they would (this is my second ship). Is that just me or do I need to adjust the servos some how? I have one of those aircraft sliding rods that connect the servo to the rudder. My current theory is that that rod is bending too much taking away some of the power from the servo to the rudder.
     
  2. warspiteIRC

    warspiteIRC RIP

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    Could be! but, servos turn about 60 degreess in each direction. If the servo wheel (arm) is a different length or the rudder link arm is, the ratio is what determines the angle of the rudder.
     
  3. tgalx3

    tgalx3 Well-Known Member

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    How could I fix that? Get a longer arm for the rudder?
     
  4. Evil Joker

    Evil Joker Member

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    what servo ? Traxxas Waterproof Servo dose not turn as well as the outhers
     
  5. Kotori87

    Kotori87 Well-Known Member

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    If the rudder isn't moving far enough, you probably need either a longer arm for the servo or a shorter arm for the rudder. A photo would help us get more specific, though.
     
  6. HMCS

    HMCS Active Member

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    what radio are you using? on LR my spectrum out of the box with a traxxas waterproof servo turned the rudder roughly 45-50 degrees to each side, when I switched over to my Futaba 2.4g the settings were different out of the box and would only do 25-30 degrees, I had to go in and adjust the setting.
     
  7. jadfer

    jadfer Well-Known Member

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    I have a Traxxas servo on the Baden and it performs the same as any other servo. The ship didnt turn as well as I wanted because at full throw the rudders were flat across the back and each other. I turned down the end point almost 30 percent and the ship turned at its best.

    In the end the rudders only needed to turn around 60% to get me turning in a circle. I was suprised by this.
     
  8. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    Interesting thing about that.. I've been doing some CFD runs on my baden's rudder setup to optimize both rudder shape, placement and throw...

    Of the three setups that made it to the final cut, the most turning force was always at ~60 degrees. one was far better than the others in predicted turning force (force perpendicular to the long center line of the ship). of the other types that didn't make the cut, some had a max at between ~40degrees-60 degrees where changing the angle between those values provided no additional turning force (but did provide additional drag); but compared to the best of the runs, these were only producing ~60-75% of the max turning force. Now I need to make the rudders and see if real life correlates to the cfd.
     
  9. tgalx3

    tgalx3 Well-Known Member

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    What end point do you mean?
     
  10. tgalx3

    tgalx3 Well-Known Member

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    My rudders arent turning enough.
     
  11. rarena

    rarena Well-Known Member

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    Two ideas,
    one, change the fulcrum point on the servo arm, bigger (further away from the center of the servo) will give you more of a turning arc. You may have to make a custom one to give enough of what you want.
    Two, if the rod is bending, support it somewhere in the middle or place it in a bigger tube for support. ie.. tube inside a tube
     
  12. jadfer

    jadfer Well-Known Member

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    In the radio you can adjust the end point. The end point is the point that the servo stops when you push the stick to one side. If adjust the end point you can tell the servo precisely (I think) where you want it to stop when you throw the stick over.
     
  13. tgalx3

    tgalx3 Well-Known Member

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    I have a hobbyking HK-T6A. There are no switches on the radio itself to do that. I have tried installing the program for it but it doesnt work for some reason.
     
  14. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    What operating system do you use?
     
  15. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    rcnavalcombat.com/Forum/tabid/58/af...fault.aspx

    Have you checked out the information available at the links in the above post?

    Another thing: on my hobby king TX, the connector on the back is intermittent sometimes, as the tolerances in the molded part are obviously not sufficient to keep all the pins connected at the same time (I.E. the pins are loose on their receptacles.... ) I had to jiggle the connector till I found an angle that gets good contact.
     
  16. tgalx3

    tgalx3 Well-Known Member

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  17. tgalx3

    tgalx3 Well-Known Member

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    ok, I dont know what software I need.
     
  18. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    First off, you need to make certain your interface cable installs correctly (drivers wise) in XP.

    Second, you need to figure out which COM port it uses. on mine, it is COM port 3, but it will vary depending on how many others your system has. you may need to plug the transmitter in, turn the transmitter on, and select the com ports one at a time, and see which communicates. Although you should be able to go into the device manager and figure it out (go into the device manager, click the plus next to ports, and if the USB cable is plugged in and the drivers are installed properly, it will say COM and a number next to the USB device. It will probably say something like "USB-UART" or something like that for the cable.

    Now, I never got the stock software to work either. to use this software,
    http://www.rcgroups.com/forums/showpost.php?p=11762129&postcount=390
    first install the ATeasy runtime environment (from the post) then download and run that guys custom software. plug in tx to cable, turn on TX. start the software, select correct com-port. then click "GET" and if it works, you are good to go. edit what needs to be edited, and click PUT
     
  19. tgalx3

    tgalx3 Well-Known Member

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    Does the radio have to be On when I hook it to the computer?
     
  20. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    Yes, it has to be on to communicate. I usually plug in and then turn on.