CIM motors

[Ether]

Originally Posted by billbo911

As promised, here is some very raw data. This is a comparison between the CIM and Mini CIM driving the same system.

In a nut shell, the the Mini CIM draws more current at the same voltage.

Using the CIM's current draw (19.4 amps) at 10 volts, the CIM's speed can be estimated.

[billbo911]

Originally Posted by Ether

Using the CIM's current draw (19.4 amps) at 10 volts, the CIM's speed can be estimated.

3726 RPM at 10v. Excellent, that confirms that it is operating exactly in the range we expected it would, 2K-4K RPM. It also confirms the video was accurately representing these numbers.

[Mr V]

Based on our shooter for last season the motor power does not make a huge difference in shooting distance, it does however affect how quickly you can get the wheel back up to speed.

We initially designed our shooter for Rebound Rumble to be powered by two 775s. One night when we were at our practice location the shooter started making a funny clunking sound. We traced it down to one of the motors. Since we didn't have a spare with us and we were mainly working on our autonomous we removed the second motor. We still shot 95% or so of the distance as we could with two motors, so we stuck with the single motor.

[AlexH]

Originally Posted by nathan_hui

Maybe we should just call them grandpa CIM, father CIM, and baby CIM.

i propose

CIM, shorty CIM, and TinyCIM

[Oldbikerider]

We're using "baby CIM" for the small one because they are so cute

Graham.

[DonRotolo]

Originally Posted by John

Not according to the VEX website. BAG motor is 217-3351, miniCIM is 217-3371.

I cannot imagine that the smallest CIM, about the size of an RS5550, can be more powerful than the Mini-CIM, about 2/3 the size of the larger 2.5" CIM (and same shaft diameter). Physically they are so very different, the larger one is most likely the more powerful one.

(I wonder where they got the name "BAG Motor" from?)

[Ether]

Originally Posted by DonRotolo

(I wonder where they got the name "BAG Motor" from?)

Don't ask.

[timytamy]

We tried the Mini-CIM on one of our prototype shooters and found that it gave an extra 1-2 meters in range without changing any other parameters, the RPM seems to play a large factor in the range of the shooter

Also we've been calling them mummy/daddy-CIM, teenage CIM and baby CIM.

[Mr V]

Originally Posted by DonRotolo

(I wonder where they got the name "BAG Motor" from?)

I'm guessing from the manufacturer's name since CIM stands for CCL Industrial Motor co.

[DonRotolo]

Originally Posted by Mr V

I'm guessing from the manufacturer's name since CIM stands for CCL Industrial Motor co.

Thanks, that's what I am guessing.

Maybe Beijing Autonomous Gearworks or something....

[Ian Curtis]

Originally Posted by DonRotolo

Thanks, that's what I am guessing.

Maybe Beijing Autonomous Gearworks or something....

Paul Copioli has some thoughts on this subject.

[billbo911]

Originally Posted by cgmv123

You have the Mini-CIM and the BAG motor confused. The BAG motor is last on the motor chart. The Mini-CIM is next to last. (The BAG Motor is the bigger of the two.) Don't fret, I mixed up the 2 at first as well.

That said, I like the BAG motor for shooting as well. You're allowed 4, so ganging 2 together comes close or even exceeds the specs of a CIM. Keep CIM's for driving and climbing.

That may very well be. My source was the "JVN Mechanical Design Calculator". I know this is not an official document. The one you linked is missing any descriptor other than the part number, so it is an easy mistake to make.