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Need a Ball-point swivel for a Project — Parallax Forums

Need a Ball-point swivel for a Project

SteelSteel Posts: 313
edited 2006-01-24 05:51 in General Discussion
Has anybody worked with any kind of swivel that is based on a ball-bearing?

I am working on a project.· I have a small (1"x1") Platform that I need to tilt on an x and y axis.· The center of the platform needs to be fairly still, but the platform needs to be able to tilt in any direction.

Has anybody come across any solutions to this, or have any sources to possibilities?

Here is an attachment of the concept.· (Very simple)
swivel.JPG
640 x 512 - 15K

Comments

  • Jon WilliamsJon Williams Posts: 6,491
    edited 2006-01-23 22:44
    Would a universal joint work?

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    Jon Williams
    Applications Engineer, Parallax
  • John R.John R. Posts: 1,376
    edited 2006-01-23 22:48
    How much weight are we talking about, and how large is the platform? How far does the platform need to tilt? Does the platform need to "captive" to the ball?

    This can be done as simply as drilling a hole with just the point of the drill, or using a countersink.

    ___________________________
    Platform with drill point "hole"
    ^
    ,,,,,,,,,,,,,,,O Ball
    ,,,,,,,,,,,,,,,|| Support

    (Note: commas are used to provide alignment, use some "virtual white out" on them)

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    John R.

    8 + 8 = 10
  • SteelSteel Posts: 313
    edited 2006-01-23 23:25
    A universal Joint MAY work, however, the platform would have to be mounted directly to the joint. The center of the platform must remain in the same place (It is a 1"x1" mirror with an optic aimed at it).

    If the Center changes, the chances of the optic source missing the mirror will increase greatly. Granted, it doesn't need to be exact, but it needs to keep in a specific range.

    It can be done by drilling a countersink, but I am looking for a 1-piece solution. (Thanks for the diagram) The reason is just to make it robust. I don't want it to be 'bumped' and the platform to come out of the countersink.

    I guess I am looking for some sort of ball/hitch method.·


    Post Edited (Steel) : 1/23/2006 11:34:57 PM GMT
  • Kevin WoodKevin Wood Posts: 1,266
    edited 2006-01-24 02:57
    You might try looking at camera tripods. There are models that operate this way.
  • John R.John R. Posts: 1,376
    edited 2006-01-24 03:47
    If you really want the center of the surface of the mirror to stay in one place, you'll need a partial ball on the back of the mirror. You need to get the reflective surface of the mirror (front surfuace or back of the mirror, depending on where the "silver" is) to be at the center of the ball. In order to make a "one piece" solution, you'd need to something along the lines of the attached image.

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    John R.

    8 + 8 = 10
    bmp
    bmp
    Assembly.bmp
    279K
  • Eric REric R Posts: 225
    edited 2006-01-24 05:01
    Try this number (Catalog #: 40-2097) at· http://www.radioshack.com·
    This might work out for you. As I recall that is a 1/4-20 nut in the middle of the top platform

    pRS1C-2277448w345.jpg
  • Beau SchwabeBeau Schwabe Posts: 6,568
    edited 2006-01-24 05:51
    It sounds like you need a 2-axis gimbal. With the attached image, imagine that the
    'white' box is connected directly to the mirror. The X-Axis 'red' and the Y-Axis 'blue'
    are connected via servo motor, stepper motor, etc. usually with some sort of a gear
    reduction.

    How much range of motion do you need? ... and what precision are you looking for?

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Beau Schwabe

    IC Layout Engineer
    Parallax, Inc.

    Post Edited (Beau Schwabe (Parallax)) : 1/25/2006 9:16:54 PM GMT
    GIMBAL.JPG
    530 x 385 - 24K
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