FRC Team 271 teaser

[logicbomb]

FRC Team 271 12cim 2 speed transmissions. Lets play some defence at championships this year (2015).

[Whippet]

So... do the other 6 CIMS get cheesecake-tethered to another robot to satisfy [R18]?

[Kevin Leonard]

Please tell me that entire transmission powers one can grabber.

[RoboChair]

Originally Posted by Kevin Leonard

Please tell me that entire transmission powers one can grabber.

I will do no such thing!

[Matt_Boehm_329]

Making an electric gokart with that?

[MaGiC_PiKaChU]

Originally Posted by Matt_Boehm_329

Making an electric gokart with that?

that makes 6HP

[Matt_Boehm_329]

Originally Posted by MaGiC_PiKaChU

that makes 6HP

That is more than enough for one

[pmangels17]

Is that a power take-off I see?

[Matt_Boehm_329]

I would love to see this thing in person

[Jay Burnett]

It would make sense if they were min-cims... them being unlimited this year and all...

[Sperkowsky]

Thats beautiful.

[asid61]

Originally Posted by MaGiC_PiKaChU

that makes 6HP

Peak? 133A * 12v * 12 motors = 19152w, or 25.6HP?

[Dunngeon]

Originally Posted by asid61

Peak? 133A * 12v * 12 motors = 19152w, or 25.6HP?

From Andymark's website each CIM produces 337Watts at maximum power.

337 per CIM * 6 motors = 2022 Watts per transmission assuming no power loss.

1 HP = 745.7 Watts (1)

2022/745.7 = 2.71 HP per transmission.

Edit: This is why using stall current for power doesn't work for DC motors



from this page

In other news, I just realized why some people use 5310RPM as the freespeed of a CIM. Assuming the CIM behaves like described in the MIT coursework, peak power occurs at 2655RPM and in the middle of the RPM range. Doubling 2655 yields 5310RPM as the max RPM for a CIM

(1) Wolfram Alpha

[Jared]

Originally Posted by asid61

Peak? 133A * 12v * 12 motors = 19152w, or 25.6HP?

That's how much power the transmission would require at stall, but the output power at stall is 0 hp because the motor isn't spinning and isn't doing work.

The output power for a motor is equal to force x velocity or rotational velocity x torque. At free speed, you have a large rotational velocity but no torque, and at stall, you have lots of torque, but no rotational velocity. Halfway in between is where you'll maximize power.

[Richard.Varone]

Originally Posted by Kevin Leonard

Please tell me that entire transmission powers one can grabber.

Those are our 2014 transmissions on top of our 2013 transmissions, but that now give me an idea *opens inventor and starts a 12CIM can grabber*, I mean who needs a drive train anyway!