Motor rpm and Torque

[D. Gregory]

What is the rpm and torque for all of this year's motors. Thank you.

[Bduggan04]

You need to download and read "The Robot.pdf" off of the FRC Documents page. It isn't as good as last year, but the basic information is still there, under "Kit of Parts".

[Gary Dillard]

I see it for the new Bosch and for the Fisher Price, but the others don't have any technical data.

Does anyone have the URL's for last year's appendix with the specs on the www2.usfirst.org site? they took the links off the main site. This has the specs for the other motors. I have a copy of the file at work but not at home. Now that i have broadband I'll download it here.

[Gary Dillard]

OK, I found a hard copy from 2000 - The motors don't look quite the same but similar enough. Since I haven't seen anybody else posting specs, here's what I've got and it will at least get you started until we see the right ones:

Window Motor (ITT Automotive): 20 Amps Stall Current, 6 Nm @ 41 RPM, 1.8 N.M @ 64 RPM

Van Door Motor (Tiagene): 75 RPM No Load Speed, Stall Torque 37 Nm Clockwise, 34 Nm Counter-Clockwise, Stall Current 40 Amps.

Globe Motor (with Drive Assembly), at 10 Vdc: No Load Speed 87 RPM, Stall Torque 150 In-Lb, Stall current 18.5 Amps, No Load Current .82 Amps.

Globe Motor (Motor Only), at 10 Vdc: No Load Speed 97RPM, Stall Torque 30 Oz-In, Stall current 18.5 Amps, No Load Current .82 Amps.

[Kevin Watson]

Originally posted by Gary Dillard
I see it for the new Bosch and for the Fisher Price, but the others don't have any technical data.

Does anyone have the URL's for last year's appendix with the specs on the www2.usfirst.org site? they took the links off the main site. This has the specs for the other motors. I have a copy of the file at work but not at home. Now that i have broadband I'll download it here.

Gary,

If you still need anything from last year, I just got done archiving it here: http://www.cvhsrobotics.org/resources.htm. You'll find the 2002 documentation toward the bottom of the page.

-Kevin

[sanddrag]

For motor specs from last year's motors and the van door motor, they may be found at www.team696.org/motorspecs.html There is also a link to download the Joe Johnson motor comparison spreadsheet.

[Tom Schindler]

Originally posted by sanddrag
For motor specs from last year's motors and the van door motor, they may be found at www.team696.org/motorspecs.html There is also a link to download the Joe Johnson motor comparison spreadsheet.

PLEASE NOTE:

the drill motors ARE different this year - do not do calculations using the drill motors on these specs...

Tom

[Gary Dillard]

Thanks for the links. Still, the motors look different than last year's, and the manufacturers are listed as different (Nippon-Denso vs Valco for the window and Bosch vs Taigene for the Van door), so as soon as someone gets the official specs please post. These should be adequate for now.

[JTH]

Did anyone else notice a discrepency in the information on the new Bosch with gearbox?

On page 5, the robot manual describes the output of the bosch with gear box as 0-450 or 0-1500, but if you take the 19670 no load RPM with the ratios of 12.07:1 or 42.62:1, you get (approximiately) 461.5 or 1630 RPM.

[Andy Baker]

I believe their numbers, but that means that the efficiencies for these gearboxes are pretty darn good.

After doing some calculations, I get these efficiencies:

Gearbox in High: 92%
Gearbox in Low: 97.5%

The "old" gearboxes had these efficiencies:

Old Gearbox in High: 80%
Old Gearbox in Low: 70%

... so...

With a larger motor, more efficient gearboxes, and a bigger circuit breakers (40A compared to 30A), these drill motors may be close to double the power compared to last year's Bosch motor/gearbox combination. Holy torque, Batman!

Andy B.

[GregT]

This is important... to choose the right motors for the right jobs, and to figure out gearings and such we need to know motor specs. Preferably stall torque, free RPM, torque vs RPM curve.

Specifically the new drill motors vs "chalupa" (if thats how you spell it). Which has more torque, what are they RPM's? Which is better to use for drive train, what are the RPM-torque curves?

ACK

Greg

[Paul Copioli]

The Chiaphua is the same motor as last year with a different shaft. It was made specifically for FIRST and is the same model number with an "FR" in front of it. See the link below for the Chiaphua spreadsheet, but disregard the pinion information.

The new drill motor has more power than the Chiaphua (see some specs below), but both are very good candidates for a drive motor.

Bosch drill motor specs (@12V):

Stall Torque = 0.87 N-m
Stall Amps = 127
Free Speed = 19670 RPM

THe above is preliminary info, but I should be getting confirmation from Bosch tomorrow.

-Paul

[GregT]

If this is correct, the drill motors are still less powerful then the atwood "chaiupas" (i will never spell that correctly)? By my conversions, the chaiupas stall at about twice the torque as the new drill motors (though both at 100+ amps, ACK!).

Someone check me, stupid english/metric.

Greg

[Paul Copioli]

The Drill motors have much more power: .87 N*M/2 * 19670RPM/2 *2*PI/60 = 450 Watts

Chiaphua power = 500RPM/2 *2.2 N*m/2*2*PI/60 = 317 Watts

Hope this clears it up. In other words, if you gear the drill to the same output free speed of the Chiaphua, the drill will have more torque.

-Paul

[Frank(Aflak)]

but the chiaphua is bigger! that means it MUST be better?!

heh, go small but powerful. If only we could replace out chiaphuas with more bosch drill motors.

Anyone want to trade (just kidding, i read the rules)