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Unread 06-03-2015, 13:29
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Joe Johnson Joe Johnson is offline
Engineer at Medrobotics
AKA: Dr. Joe
FRC #0088 (TJ2)
Team Role: Engineer
 
Join Date: May 2001
Rookie Year: 1996
Location: Raynham, MA
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Re: gear box for Denso throttle motor

Quote:
Originally Posted by AdamHeard View Post
The 775 from Andymark, or the 12V banebots 775 fill the lower power role better (as they mount to COTS items).

Don't see any point to chasing down an option for the throttle motors.
Motors lose their lives in strange and unimaginable ways* because of which, I insist that our team have several spares of each motor on the robot. Having 14 of the exact same motor is a huge benefit in terms of managing our spare parts inventory.

As to not needing 270W of mechanical power, of course that is true for nearly all of the 14 motors**. But there is little to be gained by using lower power motor like the Andymark 775, which has 1/7th the peak power yet has the same form factor & weighs almost the same.

Also, just because it is a 270W peak power motor, that doesn't mean that it HAS to be providing that much power. We can give it less voltage or even if we give it full voltage, it may be working near free speed which means that it is providing very little power.

I WOULD like to have the access to those sexy seven pole AndyMark 775 Hall Encoder*** but the ability to have common motors trumped my desire to have this very nice encoder option.

As usual, YMMV.

Dr. Joe J.


*The link is to one of my favorite poems which is not about motors at all. For a real motor death reference, look no further than Overclocked's first match at the Granite State District last week -- they almost took a fire extinguisher to our smoking drive motor. In all our practice and in all our subsequent matches, we never had another motor problem. But for a time, I was deathly afraid that I didn't have enough stock of the 775 motors.

**We have counterbalance designed into the lift and all 3 joints of our "Standard Three Joint Arm" which basically means that these motors are used to overcome friction and to accel/decel. Other than that they are just hang out. Our lift and arm motors essentially don't even get warm.

***Banebots, you should offer a long rear shaft options next year and perhaps your own Hall Encoder, yes?
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