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Unread 05-02-2010, 14:49
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Joe Johnson Joe Johnson is offline
Engineer at Medrobotics
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Re: Fisher Price Motor Power

Quote:
Originally Posted by vamfun View Post
What would you use for a Banebot 16:1 P60 gearbox? Banebot would not fess up to any number so I've been using 40%.

Do you use this factor to modify the free current (free speed) on the output of the gear box? I generally don't, but I know the friction load will slow the free speed down.
Sorry I missed this. The 16:1 is a planetary with 2 stages. I have not taken the P60's apart so I cannot vouch for the particulars, but generally, the Banebot stuff is pretty solid. I would expect that they are close to the 90% range but if it was a mission critical task, and I just HAD to be sure I had enough torque to do the job, I would drop it down to 85%.

Again, this is PER stage, so... ...general use, I would say 81% effecient from motor shaft to output shaft (effective torque multiplier of 13). Mission Critical (for example, lifting a robot), I would use 72% (effective torque multiplier of 11.5).

Callin' 'em as I see 'em since 1995...

Joe J.
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