most "epic" motor ever
 

having seen motors from years past, i have seen some beastly ones. like the van door and the minibike cim.

so, What in your is the most epic motor ever included in the KOP?

Re: most "epic" motor ever
 

I'd have to say that the Globe motor was the most versatile motor we used to get, the Cim is by far the best we get now.

Re: most "epic" motor ever
 

CIM 'nuff said

Re: most "epic" motor ever
 

The new FP and the RS-755-18 are, currently, the most powerful "smaller than a 2.5" cim" class motors.

if we expand it beyond the KOP and FIRST, this gets my vote.:D :cool: :eek: :ahh: :p

Re: most "epic" motor ever
 

I want a kit that lets you use as many CIMs and Globes as you want, and no other motors. Wouldn't that be nice?

Re: most "epic" motor ever
 

The 2011 Fisher Price Motor. With enough speed to get air over the armature it is a beast.

Re: most "epic" motor ever
 

Why were the globes ever ruled out?

Re: most "epic" motor ever
 

i think in an ideal world we would have 4 cims, 4 FP, 4 window motors.

Re: most "epic" motor ever
 

+1. In that case, this year we'd have 8 CIMs on the drivetrain, one for the lift, and two globes on the roller gripper. ;)

CIMs & Globes have been bulletproof.

So far the 775s are holding up, we got lucky with 4 good ones out of 6.

Re: most "epic" motor ever
 

Those were poseurs.

The van door motors were good in that they were the largest worm geared motors available, but they were only around 70 W output. And when it came down to using the worm gear for holding something in place, you quickly discovered that they could be backdriven one of two ways: either because the plastic worm gear's efficiency was too high, or because you'd stripped the teeth off of that aforementioned plastic gear.

Similarly, the minibike motors (CIM FP801-005/Fisher-Price) were only about 270 W. Regular (smaller) CIMs are more powerful.

My vote is for the Bosch drill motors in the kits in 2003 and 2004 (Bosch 2 607 022 078/Scintilla). Their output was 448 W, with a free speed of 19 760 rev/min. If it weren't for the tricky mounting points, the 0.7 module gear and the fragile and exposed electrical connections, they'd be perfect....

In fact, the only other motors to approach that kind of performance were the incredible self-destructing Fisher-Prices from 2005 (the Mabuchi 74550-0642, which was designed for 6 V, but given to us to run at 12 V with 407 W output power).

Re: most "epic" motor ever
 

Well, if you were looking for beastly, it looks like that was answered above.

However, I really miss the keyag motors. I don't know much about their power outuput, but it was definitely more than the densos we have now. Also, globes were great! You could use them for just about any sort of manipulator.

Re: most "epic" motor ever
 

I know everyone hates them but I really like denso window motors when used correctly. Non-backdriving and low rpm thanks to the integrated worm gear drive.

Everything else, FP and CIM.

Re: most "epic" motor ever
 

Never had an issue with a CIM or globe. Stripped, deformed, burned out, thermal tripped, or broke the leads on nearly everything else.:rolleyes:

Re: most "epic" motor ever
 

What he said, although we have managed to push CIM's to the frying point before (4 wheel long-config skid drive. The nightmares of watching it try to turn....)

Re: most "epic" motor ever
 

That was a fun year. We didn't figure out the design voltage difference until we were already committed to using two of them in an xrp transmission. It was fun finding out they were 4 times more powerful then we had anticipated.

It's a miracle we didn't kill them, or the transmission.

Re: most "epic" motor ever
 

Totally agree. they are definitely one of my favorites. I really like that the Denso gives you an output speed that you can easily work with, there are no massive reductions to deal with in most cases.

My team has a bit of Tim Taylor in them so "just put a CIM on it" can be heard just about every day.

~DK

Re: most "epic" motor ever
 

My favorite motor was the fifth CIM we got in 2010. It added a really cool twist to the game.

Re: most "epic" motor ever
 

I'm really liking the RS775-18 thus far. Seems plenty powerful, takes to stalling pretty well (better than an FP) and if it weren't for the transmissions being nearly impossible to get, I'd say they are the best motor in the KOP this year.

One year it'd be nice if FIRST gave us a list of Motors we could use with the only restriction on quantity being a total maximum power output. (Sum of all motor power can't exceed 2000W or something.) That'd be interesting.

Re: most "epic" motor ever
 

Or they could say "Each motor must have exactly 1 breaker, have fun".

*You can't have gigantic motors because the max. current per motor is limited by the 40a breakers
*You can't have too many large motors because you only have 8 40a breakers
*You can't have a ridiculous number of motors with 30a or 20a breakers, because you only have so many 30a slots as well, and a few things also use those breakers (like the cRio modules).

Favorite motors:
CIM motors are awesome for high-power things like drivetrains.
FP or 550 motors are awesome for high power but more predictably-loaded things (such as arms) or high power, light weight things (like roller claws or other high-up mechanisms)

An AMP or CIM-U-LATOR makes the FP or 550 think it's a CIM.

I would be very happy to just have those two motors. Most things would use a CIM interface, and the limited number of CIMs could be distributed, and the rest could get FP or 550's through CIM-U-LATORs. Anything without a CIM interface would accept a FP or 550 directly.

Re: most "epic" motor ever
 

to your team, anything that can be mounted to a dewalt tranny is fair game :D

Re: most "epic" motor ever
 

I second that

Re: most "epic" motor ever
 

I liked that gearbox with 6 motors on it that I saw from an '07 game, I think it was called the V6, 4 CIMs, 2 smaller ones. Anyone remember this?

Re: most "epic" motor ever
 

118's V6 was pretty cool.

Re: most "epic" motor ever
 

CIMs are the best permanent magnet DC motors I have ever used - in FIRST, at work, in school, etc. We had been unable to destroy one in 12 years (until this year thanks to an overzealous rookie and some incorrectly sized mounting hardware)!

I like the suggestion for unlimited CIMs and Globes (or a suitably robust similar "small" motor - the RS550s might be up to it).

Re: most "epic" motor ever
 

Eh, I'd like some sort of constraint on CIMs, just so we don't have 8-motor drive trains that ram into everything in sight or are nearly impossible to get out of the way of. The CIM takes the cake for 'epic' for their robustness.

I like the motors that spin slowly enough out of the box that I don't NEED to gear it down 1000:1 using a $200+ COTS gearbox or multiple sprocket reductions -- the denso's and the globes were PERFECT for that. Need a wrist joint? Just add 1 sprocket reduction after the motor output. To me, it's more of a challenge to figure out how to do things with less available power than it is to use less power via software.

Re: most "epic" motor ever
 

[quote=JesseK;1033040]Eh, I'd like some sort of constraint on CIMs.../QUOTE]

How about weight? Each 2.5" CIM weighs aout 2.5 lbs IIRC. 4 = 10lbs, 8 = 20 lbs. Unless someone knows some magic I don't there really isn't any way to lighten them. At some point most teams are going to have to use lighter motors so as not to eat up so much of their 120 lb weight budget. I think allowing 6 CIMs at most would be a reasonable thing to do unless they up the 120 lb weight limit, increase the number of 40A slots on the PD board, and up the 120A main breaker - none of which I see happening anytime soon. There are plenty of contraints already limiting the "unlimited use of CIMS".

Re: most "epic" motor ever
 

[quote=DeepWater;1033098]Don't forget power draw, pulling down 40+ amps for any extended period of time with 8+ CIMS will quickly suck your battery dry.

Re: most "epic" motor ever
 

[quote=DeepWater;1033098]I'm not so sure I want any team to slap 8 CIMs on their drive train and only to call it a "defensive" robot. Heh. Sorry, our robots have to survive for the post-season while also playing the game without breaking every other match.

It's like the whole debate upon regulations of car safety. More powerful engines and higher speeds equate to more structural strength necessary to prevent deaths on the highways. This means more weight added to cars as well. Rather than limiting power output, the typical regulations are on structure integrity during a crash. If the industry would tone down the power a bit, we wouldn't quite need all of that regulation.

Conversely, since FRC has a pesky weight limit, we do not necessarily have the spare weight for adding more structural integrity to EVERYTHING we design. So I'd much rather the GDC limit the power capabilities to the drive train as a slight preventative measure to prevent 'overkill' scenarios. As it stands right now, teams who want a 6-motor drive train have to do more engineering than just purchasing COTS gearboxes and slapping them on the KOP drive train. That in and of itself is limiting enough for quantity seen on the field, I think.

Re: most "epic" motor ever
 

2.5" CIM motors, followed closely by the Banebot RS775-18. While much praise has already been espoused about the versatility and durability of the CIM motors, we've found that the Banebot RS775-18 motors are close runners up. Unlike the other BB motors, the RS775's are champs and won't give up the ghost just because you told them to run at stall for a few seconds. During testing, we learned they'll trip out the Jaguars or circuit breakers long before they'll suffer any harm.

Putting 8 CIMs in a FRC drivetrain won't really accomplish anything other than to deplete one's battery faster. This is because of the major difference between your example of cars and FRC robots: Most FRC robots are traction limited, while cars are usually torque limited. Adding more powerful engines to cars yields better results because torque-limited cars have a large capacity void between what the stock engine puts out and the maximum power than can be utilized by the wheels to make the car go.

On the other hand, adding more power to an FRC drivetrain may actually lower a team's effective pushing power, as dynamic friction is almost always lower than static friction. (Think back to Lunacy). Thus, by having more motors in a drivetrain, they will increase the odds that the motors will be able to overcome the maximum static friction with the ground and start spinning their wheels, thus lowering their ability to push other robots.

Now even if they can overcome the traction limitations, they still have to deal with the relatively small field size. How likely is it that robots will have the room to accelerate to speeds beyond the top speeds of 15-16 ft/sec already seen on many FRC robots? Why do you think teams don't currently use three or four speed gearboxes that can theoretically take their robot to 20, 25, or 30 ft/sec? It's because the field is small enough such that gearing for that speed would never be useful.

Re: most "epic" motor ever
 

While that's one very valid reason, a 4 CIM drivetrain takes a noticeable acceleration hit at around the 18 FPS mark. Current two speeds don't need to auto-shift for acceleration purposes; a faster drive would basically require it.

Re: most "epic" motor ever
 

They've been discontinued for several years. We were still using them for a few years after they were out of comercial availability.

Re: most "epic" motor ever
 

Don't forget the huge voltage drop that can occur if the CIM's change their input voltage to fast; it's pretty easy as-is with 4 CIM's to brown out the system if you go from stop to full power. With 8, or even 6, the current limit starts to become a major factor too.

Re: most "epic" motor ever
 

Doesn't that depend on whether the driver is blindly giving it full throttle (spinning the wheels), or modulating the output in proportion to what the robot is doing? (Or better; the cRIO is handling this for him.) And in the case where a robot is geared rather high, and therefore is using a high power setting to push as hard as it can, by having more motors, the load will be distributed among them. Although the output force is limited by traction, with more motors, each will each be operating at a more desirable point on the efficiency curve; that gives the robot more endurance.

So there's a trade: is the added complexity, weight and opportunity cost (in terms of not having those motors on another mechanism) worth it? In drivetrain-heavy games where robots are operating at high power most of the time, my sense is that this is often a good decision.

Though I don't know how often this figures into teams' design decisions, I'd say that the current state of the art with FRC transmissions is such that none can shift fast enough to make more than two speeds really valuable. Though that's far from an absolute rule, I haven't seen any 3+ transmissions that can shift fast enough to make the unpowered time between shifts worth it for accelerating a robot. Even many two speeds are (counterintuitively) sacrificing acceleration for endurance (because the ratios in each gear mean less total power consumption, due to motors operating at more efficient points).

For example, a servo-shifted Super Shifter with default configuration, mounted in place of the Toughboxes on a 2010 kitbot probably should just stay in high gear most of the time: there's no point waiting a half-second for the shift to happen.

So, returning to the constraint of limited field size, and recalling the previous discussion about motors, I'd say the most practical way to achieve really high speed (in the current FRC game) is lots of motors and a high gear ratio.

Re: most "epic" motor ever
 

Arthur, I agree with you about traction limiting to a point. Pushing wasn't the concern -- high speed ramming is (hence, the highway safety analogy). More motors nets more acceleration in shorter distances, meaning the occurances of high speed ramming would go up. Could we adapt? Sure. Yet why should we have to adapt to that when the overall build season / competition experience in its current form is already stressful enough?

Re: most "epic" motor ever
 

Add a poll to this. Then you will see the results teams think.

Re: most "epic" motor ever
 

Vandoor Motor, hands down.

Yes, it's old. Last included in 08 kit. But by god, there's a reason that we joke that is has more torque than a toyota camery in the camery's highest gear.

Re: most "epic" motor ever
 

I'm going to have to say that size to punch, I am REALLY REALLY liking the BaneBots rs775-18 motors. They're just darn cool motors, and they're a lot more versatile than people think. Just make sure your power leads aren't grounded to the case.