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Show me your Universal Joints

Discussion in 'DIY Motion Simulator Building Q&A / FAQ' started by Psionic001, Feb 9, 2019.

?

Do you make your own Joints or buy after market

  1. Designed and Built my own joints

    32.0%
  2. Purchased after market

    60.0%
  3. Found another way to use joints

    4.0%
  4. I don't use joints

    4.0%
  1. Dirty

    Dirty Well-Known Member Gold Contributor

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    Thanks, appreciate the compliment :)

    They are designed for a nominal load of 1000N (~220 lbs) and I have tested them up to 4000N (PETG@285°C) This is the extension load, btw. In compression they should easily hold much more than that.

    Also, I have designed them around metric ball bearings. I think it was these:
    Screenshot 2023-08-27 at 18.50.22.png
    ...which are dirt cheap and are available from a hundred vendors here in Europe. If you guys over in the US use inch or other units for typpical off-the-shelf bearings you may have to adapt the design slightly. And if you are OK with smaller diameter bearings, you can significantly increase the range of movement by reducing the size of the "arches". Even a millimeter (~40/1000 ") will make a noticeable difference.

    It you choose to go with those, build a single prototype first and see if it suits your needs. And let me know if you run into issues 'cause I am not using those myself. I went with the single-sided ones.

    Dirty :)
    • Informative Informative x 2
    • Agree Agree x 1
    Last edited: Mar 24, 2024
  2. Gianny

    Gianny New Member

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    My Motion Simulator:
    2DOF, Arduino
  3. pmvcda

    pmvcda aka FlyPT

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    My Motion Simulator:
    6DOF
    Anyone wants to try flexure joints?
    Flexure joints are impressive, no gaps and solid. When looking for high precision and repetition, it's the best solution
    upload_2023-12-2_17-50-8.png
    Here's some info:
    https://ris.utwente.nl/ws/portalfiles/portal/17709852/4927.pdf

    They are not in the maket we need to go the DIY course, but might be easier to build compared to a conventional ujoint.

    And an application of that:
    • Like Like x 3
  4. Yeti86

    Yeti86 New Member

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    i got myself a drive train axle here from a VW t4 that i was planning for the build.
    it would have had two u-joints and could have been cut and welded just fine.

    but settled on regular bearing blocks as shown, the advantage of that is that i used one bigger shaft on one side, so i could drill and tap a setscrew. that allowed me to balance the center of gravity by sliding the other side along.

    Attached Files:

    • Like Like x 1
  5. cfischer

    cfischer Active Member Gold Contributor

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    Wow that is super interesting. Thanks for posting!

    Im super intrigued by both the uv joint and the motor flexure in that video. Really cool stuff.
  6. pmvcda

    pmvcda aka FlyPT

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    My Motion Simulator:
    6DOF
    • Like Like x 1
  7. issalig

    issalig New Member

    Joined:
    Nov 22, 2024
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    Europe
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    My Motion Simulator:
    2DOF, DC motor, Arduino
  8. issalig

    issalig New Member

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    My Motion Simulator:
    2DOF, DC motor, Arduino
    For some reason, the image is not shown in the post before.
    I have uploaded it again as an attachment.

    Attached Files:

  9. Dude

    Dude New Member

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    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform
    Hey Guys
    I'm in the beginning phase of my own project, a spaceship simulator. This topic helped me a lot to come to my solution, so thanks a lot already!
    To keep things cost effective but not cheap, i came up with the following construction. It's a combination of an aluminium cross block for 3d printing or automation, two 20mm steel pipes and 4 heavy duty ball bearings.
    IMG_0311.jpeg IMG_0309.jpeg IMG_0308.jpeg
    All in all costs: $45. Can provide links if it's allowed/wanted.
    • Creative Creative x 1
  10. hexpod

    hexpod http://heXpod.xyz

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    My Motion Simulator:
    DC motor, 6DOF
    If you are aiming a 6-dof you need to allow a slight rotation on vertical axis on the actuator.
  11. Dude

    Dude New Member

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    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform
    Just aiming for 2-dof. The simulator will be a closed cabin. I'll open a thread as soon as there is more to show than the gathered material.
    • Like Like x 1