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Unread 28-01-2016, 00:16
kitare102 kitare102 is offline
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Re: Need Specific Help Regarding Mathematics and Motor Choice of Arm

Quote:
Originally Posted by MAXOFLIFE View Post
Thank you! If we continued with this design, would switching to 1 miniCIM be more efficient? Also, how does the belt system in our design play into the math for calculations?
Switching to only one miniCIM will use less power, but make your arm accelerate slower as it pulls the portcullis. Efficiency of power shouldn't be an issue, but it's possible efficiency of time will be hurt moving to one motor. That being said, you should be able to get a fairly responsive arm to move using just one miniCIM. MiniCIMs are fairly heavy, and gearboxes to handle 2 CIM profile motors have to be larger, so moving to one miniCIM will save a notable amount of weight if that's a concern.

As for the belt, you'll have a reduction where the "driving gear" value should be the number of teeth on the pulley connected to the gearbox and the "driven gear value" should be the no. of teeth on the dpulley connected to the arm's axle. In your spreadsheet currently, the 18 and 84 could represent an 18t driving pulley and an 84t driven pulley.

Right now you have two 10:1 reductions in your spreadsheet. AIf those are versaplanetary stages, I'd like to point out that the user guide for that system suggests not using two 10:1 reductions with a miniCIM. However, due to the relatively higher rigidity of the teeth of lower reduction stages, a 100:1 reduction composed of 2 5:1 stages and a 4:1 stage (for example) is greenlighted. If you're using a different system, disregard this paragraph (though checking out user guides is always good).

Last edited by kitare102 : 28-01-2016 at 00:18.