Fisher price for the drivetrain?

[merybar]

Our team is looking into switching from CIM's on the drive train, to the fisher price series. Anybody ever done this before? The idea is that with the significantly limited amount of friction this may work. Any thoughts?
Thanks everybody!

[colin340]

i have done a Cim and Fisher Price drive tran and i think it would be fine as long as you don't really gear it high even on the low friction floor, you still have to get them moving.

[merybar]

ok thank you!

[writchie]

Beware that the 9015 motor for 2009 ( and 2008 ) has significantly less power than those of earlier years. This years motor has a peak power of about 180W compared to 337W for the CIM. RPM on the FP's is about 3 times the CIM. You can turn an FP into a CIM mounting "thing" with an Andy Mark gear box. This might have sense for a drive motor (or 2nd drive motor) with the older FP's because there power was as least at a similar level.

The FP motors are fan cooled and so they need to spin. They easily overheat and when they do the plastic mounting slips making matters worse. You don't want to be anywhere near the right side of the power curve.

Generally, its better to use CIM's for drive motors and the FP for other things where you have better control over the speeds/loads etc. This year, you most likely need only a pair of CIM's leaving two for other uses.

If you do end up using them make sure you do the math. Also try to rig additionally cooling and make sure you have spares.

[waialua359]

CIMS are definitely better than running the FP for the drivetrain, ........on carpet for sure.
This year's glassline surface.......try it and let us know. :)

[Gamerboyb1]

Oh, gosh who let Colin in here. Yeah that idea has won Sparxs so pushing wars over the years and using an Andymark planetary trannie with them helps to utilize them very well.

[merybar]

Beware that the 9015 motor for 2009 ( and 2008 ) has significantly less power than those of earlier years. This years motor has a peak power of about 180W compared to 337W for the CIM. RPM on the FP's is about 3 times the CIM. You can turn an FP into a CIM mounting "thing" with an Andy Mark gear box. This might have sense for a drive motor (or 2nd drive motor) with the older FP's because there power was as least at a similar level.

The FP motors are fan cooled and so they need to spin. They easily overheat and when they do the plastic mounting slips making matters worse. You don't want to be anywhere near the right side of the power curve.

Generally, its better to use CIM's for drive motors and the FP for other things where you have better control over the speeds/loads etc. This year, you most likely need only a pair of CIM's leaving two for other uses.

If you do end up using them make sure you do the math. Also try to rig additionally cooling and make sure you have spares.

I appreciate the help on this. I will defiantly check into the math,
Thanks
Matt

[Teched3]

Just to add another thought or two. Remember, you may be running on carpet at times on the perimeter, and the F/P motors do not like to be stalled. If you do use them, make sure you provide venting paths where you mount the motors. If you don't they will overheat quickly with no air movement even if they aren't stalled. Take a close look at the F/P gearboxes the motors are mounted on to see where the vents are located and sized. That is if you use different gearboxes.:)

[colin340]

Just to add another thought or two. Remember, you may be running on carpet at times on the perimeter, and the F/P motors do not like to be stalled. If you do use them, make sure you provide venting paths where you mount the motors. If you don't they will overheat quickly with no air movement even if they aren't stalled. Take a close look at the F/P gearboxes the motors are mounted on to see where the vents are located and sized. That is if you use different gearboxes.:)

good point keep um cool
-also make sure you press them in to the drive gear on the AM with up most care
-and a bit of grease applied to both motor bushings before you put them in to a gearbox can't hurt

[Kit Gerhart]

I pretty much agree with what everyone has said. If you don't gear them too high, they should do fine on this low traction surface. I'd gear for not more than 10-12 FPS or so based on the no-load rpm of the F/P's, and gearing even lower would certainly be better for keeping the motors from getting fried.

Still, I'd use two CIM's for your drive unless you REALLY need them for other robot functions. They are so reliable that we go through a competition season, and then drive our robots for years doing demos and practice without having to replace CIM's on our drive.