2006 Motor Specs

[Price Vetter]

I have searched for this years fischer price motor's (not the big CIMs) pitches and can't find them. Does anybody know what it is?

Also measuring motors with strobes is VERY subject to aliasing.

[billbo911]

Originally Posted by petek

Basic specs on all the motors are in
FIRST Guidelines, Tips & Good Practices. Glad I went looking for this because FIRST posted a new revision.

Basic specs is correct, mostly power, torque, no load RPM and current draw. What I am looking for on the van door motor is the mounting hole layout and thread size and pitch. I know the output shaft is 11mm in diameter, this leads me to believe the mounting holes are metric as well.

[petek]

Originally Posted by billbo911

Basic specs is correct, mostly power, torque, no load RPM and current draw. What I am looking for on the van door motor is the mounting hole layout and thread size and pitch. I know the output shaft is 11mm in diameter, this leads me to believe the mounting holes are metric as well.

I don't think I've seen a manufacturer's dimensioned drawing of this motor anywhere but if you go to FIRSTCADLibrary, Ed has it modeled on the Motors page. He doesn't have the threads spec'ed, and appears to have used inch units, but at least the hole circle is there. I believe you're correct about the metric mounting holes (M6?), anyway.

[Joe Johnson]

Originally Posted by petek

I don't think I've seen a manufacturer's dimensioned drawing of this motor anywhere but if you go to FIRSTCADLibrary, Ed has it modeled on the Motors page. He doesn't have the threads spec'ed, and appears to have used inch units, but at least the hole circle is there. I believe you're correct about the metric mounting holes (M6?), anyway.

There is no question mthat the ounting holes are M6. I am 100% certain on this.

Also, I am 99% that the mounting pattern is the same as it has been for every van door motor that has been in the FIRST kit (i.e. the bolt circle radius is the same).

Joe J.

[Paul Copioli]

Joe is correct, the mounting pattern is the same as the last few years. The screws are M6.

[Richard Wallace]

Originally Posted by Spencer295

Richard because your test results vary so drastically from the specs on previous posts on motor wattage, would you mind testing the old cim motors on your dyno so I can make an accurate comparison.

I finally got my hands on an old CIM motor, to measure speed and current vs. torque on my dynamometer. [N.B.: had to order some spares in case the team burns one up testing.]

Your suspicion that my measurements are low compared with published specs is correct: I measured peak power about 270 Watts (c.f. 337 published) at about 2700 RPM, drawing 50 Amperes.

There are several reasons my measurements might be low, but accurate dynamometer torque calibration is not one of them. The most likely (IMO) reasons are (1) I let the terminal voltage drop off at higher current draw due to lead resistance, about 5 ft. of 10 qmm (~7 AWG) for each lead from the supply terminals to the motor lead connection point, and (2) I let the motor get hot while taking readings. Imperfect shaft alignment and residual drag torque in the magnetic brake probably amount to about 25 Watts.

It has been my experience that the above loss mechanisms are also present, to about the same degree, in drivetrains that I have built for FRC robots.

[Stevo]

Ok, so I know that the spec sheets are out there on both CIM motors (FR801-005 and -001), but I cant seem to find how much current the FR801-005 pulls under NORMAL load. I saw somewhere the specs for free load and stall, but no NORMAL load. If anyone out there could shed some light on this, it would be much appreciated.

[Madison]

Normal is a relative term. The current draw varies between the free current value and stall current value as load is applied. If you have some idea of what load you're applying to the motor, you can determine the current draw using the information provided in the spec. sheets. If you don't know the load, but can measure the shaft speed (e.g., RPM), you can work backward to find the load as well.

[Loki1989]

how fast will the wheels go with 120 pounds on them if the gear boxes have all four motors in them and the wheels have a 25 in circumfrence

[Madison]

Closing this in preparation for the new season.