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Motion Transformation

  1. Jul 13, 2006 #1
    In many ways I am unsure of the question that is in my head... but I would assume that there are others out there who understand the need to ask whilst the problem is still fuzzy. I need some direction: how can I convert a rectangular motion into a rotary motion? Is this even possible? Those steadfast to the answer "no" need not respond. Imagine a rectangular motion path with an arm outstretched from the path. Could a combination of gears create a somewhat fluent circular motion?

  2. jcsd
  3. Jul 13, 2006 #2


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    Staff: Mentor

    I'm not exactly sure what kind of motion you are talking about, but any reciprocating engine converts linear motion to rotational via a crankshaft.
  4. Jul 13, 2006 #3
    I know its probably an incredibly simple question... but its not straight linear motion but rectangular motion. Imagine a crank on a wheel but rather than a circle its a rectangle... and it moves along the rectangular path.
  5. Jul 13, 2006 #4


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    Gold Member

    A crank on a rotating rectangle with still trace out a circular path. The only way that I can think of to get 'rectangular' motion would be with some sort of cam-slot arrangement or chain/belt drive on sprockets/pulleys. Could you possibly post a diagram of what you mean?
  6. Jul 13, 2006 #5


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    Science Advisor

    If you have a slider with one end going around a rectangular path and the other end connected to a point (not the center) of a wheel or gear, the gear should still rotate. The rate at which the wheel will rotate will change, but it will rotate. You would probably have to play around with some kind of guiding mechanism though to ensure that the connecting arm doe not allow the motion to reverse.
  7. Jul 13, 2006 #6


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    A simple ratchet should take care of that, as long as it's set up so it can't lock in an attempted reverse position. Perhaps 2 indepentantly linked connecting rods?
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