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Motor for a project

  1. May 24, 2013 #1
    I do not know much about motors so I was wondering if you all could help me out a bit here. I am looking for a small electric motor that does not need to accelerate fast, but can propel about 150lbs as fast as possible when connected to a 110mm wheel. It will need to be battery operated. I am a bit flexible on the dimensions, but would prefer it to be no larger than 100mm x 100mm x 100mm. I hope I explained it well enough for you all to understand. If not, let me know. Price at this point isn't an issue.

    Thanks a bunch!
  2. jcsd
  3. May 24, 2013 #2
    I'll defer this to more experienced guys, but I'm thinkging...well, "No way".

    150lb is really heavy. How do you mean "connected to a 110 mm wheel"?

    A motor that is 10 cm on each side is tiny, it's not going to have very much power especially if its source of energy is a battery.
  4. May 24, 2013 #3
    It would be connected by affixing the motor inside the 110mm wheel with the shaft connected to a stationary plate so the body of the motor rotates the wheel.

    I know it's a long shot, but I'm hoping there is something out there. As I said the dimensions are not firm but preferred, and t doesn't have to last very long on a charge.

    Edit: I also forgot to mention that 2 motors can be used in tandem for this project.
    Last edited: May 24, 2013
  5. May 24, 2013 #4
    I don't understand, why do you want the motor body to spin with the wheel? That's not the way they're designed to operate, the shafts especially.

    And what's the 150 lb? What does "propel" mean in this application?
  6. May 24, 2013 #5
    I'm doing a bad job of explaining things. Think hub motor.
  7. May 24, 2013 #6
    Ahhhh, I see what you meant by that, sorry. Misunderstanding on my part.

    I'd look up the manufacturers numbers first, and get in contact with them. They'll be better able to tell you the limitations of the existing technology given your specs. The limiting factor here will probably be your battery specs.
  8. May 26, 2013 #7
    Gentle suggestions:

    are both worthless attempts at specifying motion parameters.

    A small motor 100 x 100 x 100 is certainly capable of moving a load of 150 lbs. But it may only deliver sufficient torque that must be geared down and applied so that the resultant motion is very slow. You don't set any parameters to determine if "slow" is good enough, or not.

    You need to do a dynamics analysis based on defining peak torque required to turn that 100mm diameter wheel to move your mass. Only then can you determine if there is a motor on the market that will work, and whether it must be combined with some sort of gearing.

    Websearch for "The Smart Motion Cheat Sheet" in PDF format that summarizes the analysis and equations. Otherwise procure some Engineering Guides from any of the prominent gearmotor manufacturers to educate yourself on how to do the analysis.
  9. May 28, 2013 #8
    Yeah... thanks for your colorful jab at my motion parameters. I'm sure you're great at parties. Otherwise thanks for the rest of the information. I'll do my best to educate myself.
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