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Unread 17-05-2015, 21:05
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Bryce2471 Bryce2471 is offline
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Re: pic: Short coaxial swerve module

Quote:
Originally Posted by glennword View Post
While I applaud your efforts, I have to ask, what benefits does having the CIM in a horizontal orientation get you? And are those benefits worth the extra complexity, part count, efficiency loss from the extra miter stage, and potentially weight? (not sure if the last one is a factor or not) The only benefit I can think of that might even be measurable is a lower CG, although I don't foresee that being much of a difference. I would suggest investigating worm gears in the future if you wish to bring this design into reality. You can get a nice, high, relatively efficient reduction in a single stage, and it sets you up nicely to go coaxial. Anyways, I love seeing your designs posted here fairly regularly, you have a tendency to think outside the box which is fantastic. Keep up the good work!
This was a design exercise for me to see how short I could make a coaxial swerve drive. In order to make the module shorter than a CIM motor is long, I had to put it sideways. I agree that there is likely not a huge benefit of doing it this way, but it was something I wanted to try out. I do think it is the lightest and most compact swerve I've ever designed, although that is likely for reasons other than the horizontal CIM.
Quote:
Originally Posted by Joey Milia View Post
I won't dispute worm gears high reductions but i wouldn't describe them as relatively efficient. The highest efficiently you'll get is 86% with a four lead worm. At best this would be replacing the two stages before the co-axial, a miter stage and a timing belts stage, each around 95% or higher. I too am unsure of the benefits of a horizontal cim for a coaxial swerve but I don't think a worm gear would be beneficial on the Cim motor. However, using a worm gear for the steering motor is a different issue and has more merits in my opinion.
There is also the fact that I'm only looking for a 1.5:1 gear ratio out of that section of the powertrain.
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Last edited by Bryce2471 : 18-05-2015 at 16:37.
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