FP 9003 vs 9012 (was Attention Robot Inspectors:)
 

Attention Robot Inspectors:

Apparently the FP service centers didn’t get that memo mentioned in Update #8”
Nor do they fully understand that all 19-tooth FP motor/gearboxes are NOT created equal, not in the eyes of FIRST. They had me waste a 40-mile trip to one store by saying they had five, which turned out to be a mix of Mabuchi and 9003s. Another store could not locate any by part number, but realized they had four when I described how to identify the 9012, which brings me to the point of this post.

According to the guys at the service centers, some teams didn’t care if they had the right motor. Some even figured they could “get away with it” by swapping the sleeve with part number on it.

FYI: The 9012 has four cooling slots, which are slightly smaller than the two slots on all the others (Mabuchi – 9003) I’ve seen.

Re: Attention Robot Inspectors:
 

Some more information, for those who are interested:

The Mabuchi F-P motors (all illegal for 2007) are identifiable by the back end, because they lack the four ventilation holes on back end of the Johnsons (viz. Johnsons from the inside); the Mabuchi F-Ps look pretty much like the little Mabuchi motors, from the back, with distinctive curved slits. (Actually, according to Mabuchi's site, there's a new design for the RS-550 motor; compare the RS-545 to the new RS-550. The old-style RS-550s issued to FIRST teams should look like the RS-545 when viewed from the back.) Other differences between Mabuchis and Johnsons include the stick-on model label on a Mabuchi, vs. the painted numbers on a Johnson, or the "M" vs. "JE" logos. Inspectors can easily check for this, and catch obvious violations.

The Johnson 9012 looks the same as the 9003, and the same as the higher-powered Johnson F-Ps from 2002 and 2004. That unfortunately makes them indistinguishable at a glance, apart from the model number. (The pinion was different on the 2002 motor, but since the pinions are replaceable, it doesn't matter.) The 9003 lacks the internal thermal protection of the 9012, but is otherwise largely equivalent (though still illegal). The other motors are rated upwards of 200 W (mechanical power), and represent a competitive advantage over the approximately 170 W of the 9012, if substituted in violation of the rules.

Re: Attention Robot Inspectors:
 

So in the chaos that was the build season, none of us ever checked if we got the correct version of the FP in our KOP. Shame on us for assuming that we could use the parts provided in the KOP.

When we check these on Thursday of the Boston regional we will find out for sure. If we happen to have the wrong ones will FIRST have the correct ones on hand for us to use?

Also, does anyone know if the 9012 motor and the 9003 motor have the same size pinion? We had to modify the FP gearboxes and it would be much better for us if the motors could be switched into the same gearboxes (provided that we even have to switch).

Thanks,

RAZ

Re: Attention Robot Inspectors:
 

Ok, so after going through a bunch of pictures from our build season, it is apparent that we were supplied with illegal FP motors in our kit. The link below shows what it looks like.

http://www.tomschindler.net/our_fp.jpg

It is very important that we find out if the pinion gear is the same on the 9012 and 9003 motors. If it is not, I need to find out how many teeth each has so I can be sure to have the appropriate parts to put the 9003 pinion on the 9012 motor. If anyone can help with this we will be eternally grateful.

Please share any info that you have.

Thanks,

RAZ

Re: Attention Robot Inspectors:
 

Rob,

We were given the 9003's as well, but did not use the F-P motors on our robot at all. Therefore, we never asked for replacements from FIRST. Our 9003 motors are still untouched at the shop. I'll take a look next week and confirm what our pinion size is. If someone else has an unused 9012 to compare, we'll have our answer.

For information sake, I believe that most of the 9003's were given to teams that attended the Manchester, NH kickoff. (So, mostly New England teams had this problem...) The Manchester KOP's were packed last, as they didn't need to be sent in advance. These 9003's were leftovers from previous years, so they were probably inadvertantly mixed in at the time of KOP packaging.

Off to catch up on some sleep...

BEN

Re: Attention Robot Inspectors:
 

If they're the 9003s left over from last year, they have the 19 tooth pinion, like the current 9012. You can verify things without taking the assembly apart by looking for a raised "19" in two places on the black (or white) F-P gearbox case. Other versions will have a different pair of numbers. Be aware that it's just the 9003 motor that's illegal; the gearboxes are COTS items (from a F-P service centre), as are the pinions.

188's KOP 9012s and the identical spares were all equipped with the 19 tooth pinion, as were the 9003s from last year.

Re: Attention Robot Inspectors:
 

All ten of our 9003s have two cooling slots; all seven of our 9012s have four.

Some 9003s came with 16 tooth pinions, others came with 19 teeth.

Rob - the easier route to matching motor to transmission is to swap the drive gear in the transmission (the one that mates with the motor pinion). Irrespective of what Update #8 says, you will most likely have to buy the motor/gearbox combination; so you'll have the proper gear.

Re: Attention Robot Inspectors:
 

Jack, Ben, Rob, et al,

Have you informed FIRST of this issue?

Mike

Re: Attention Robot Inspectors:
 

Mike, I "unofficially" informed FIRST. Meaning, I didn't go through the proper channels (re: email) to inform them. I also did not ask for replacements, as I knew that we weren't using those motors in our design this year. Other people have posted about their communication with FIRST on this subject, and it sounds like their issues were never resolved. Specifically, I know that BUZZ asked about the 9003's in the Q&A, and I don't think they ever received the replacement motors. (Jim Morin would obviously know better than I...)

BEN

Re: Attention Robot Inspectors:
 

N0 - it's not an issue for us any more. That may sound selfish, but there's not enough hours in the day to spend any telling them what they should already know.

Re: Attention Robot Inspectors:
 

Hi Guys,

Thanks for the information and advice. We are contacting FIRST about this issue today, hopefully we can get some replacement motors. I think this could be an issue for many other teams. If Ben is right and New England teams got the wrong parts, then I am very concerned about the Boston event. There are alot of rookie teams who do not have a presence on these boards who might be in for a rotten surprise on Thursday.

On the positive side, at the beginning of the season I had some kids take apart one of the FP gearboxes to learn a bit about ratios, and I *seem* to recall the pinion having 19 teeth. If that is the case then this is an easy swap.

The only question I have on this is what is the performance difference between the motors? I am not worried about power because our system is overpowered anyway, but max speed is a concern. If there is a big difference in max rpm then we will have to change out some of our sprockets as well.

Thanks for the help,

RAZ

Re: Attention Robot Inspectors:
 

I checked Team 95's, and ours are the 9003s. And we got them at Manchester.

We're not using them on the bot, however. (Unusual, we usually use them).

Re: Attention Robot Inspectors:
 

Hi Guys,

After doing a bit of research on the 2 motors (9012 and 9003) and talking to FIRST, we are making much ado about nothing. The two motors are virtually identical and should be interchangeable. Recall that both were in the 2006 KOP with some teams getting one style and other teams getting other styles.

Looking at the 2006 tips and good practices document, the motors have almost the exact same performance.

Link to the document showing the motors are almost identical is below:
http://www2.usfirst.org/2006comp/oth...ices_Rev_D.pdf

I would strongly suggest that FIRST just allow both 9012 and 9003 motors and let this non-problem go away.

Either way, we had some 9012 motors shipped to us so we will be safe either way.

Best of luck to everyone,

RAZ

Re: Attention Robot Inspectors:
 

By definition, motors supplied by FIRST in the kit should be legal.

The notion that the 9012 and the 9003 are equivalent, however,
is a stretch. The 9012 has the internal current protection
and the 9003 does not. This difference is huge when a motor
is operated close to full power to lift a robot. We had to specifically
modify our robot lift to change the gearing to keep the internal current
limiter in the motor from popping midway through the lift, even
though the circuit breaker for the victor controlling the motor was
the 20 amp one.

The 9012 motor is easly obtained, although you might have to
sort through the parts that Fisher Price wants to sell you. If
the 9003 is declared legal we will happily swap the 9012 out
to ditch the internal current limiter.

Eugene

Re: Attention Robot Inspectors:
 

Excellent points Eugene, I hadn't thought about the current limiting feature (probably because our application operates well below stall torque and doesn't draw much current).

There are noticeable differences depending on your application, so maybe FIRST is justified in sticking with the 9012 motor. We are prepared to swap on Thursday of the Boston event.

Best of luck to everyone!

RAZ

Re: Attention Robot Inspectors:
 

I hope those are your words, not FIRST's. If their's, I wonder why I called all over and drove 120 miles to get the right ones. If their's, I guess the FP service center guys had me pegged when they thought I was nuts for caring!

Re: Attention Robot Inspectors:
 

Those are my words, not anything from FIRST. As far as FIRST is concerned, the only FP motor that can be on your bot is the 9012 version.

The reason I was saying much ado about nothing is that I was worried all of the hours tuning our control loops for the arm would be brushed away if the motor performance was different after the swap. Since the motor performance is identical in our application (not near stall torque and low current) I have no concern that changing the motor will cause us to have to re-tune our system.

Thanks for the help.

RAZ

Re: Attention Robot Inspectors:
 

When we mechanically busted a FP (busted it up good!), we called our FP service center and they knew exactly what we needed. However, the gear box they had with the clearly marked correct part number had the wrong FP motor in it - a 9003 instead of a 9012. We were going to shrug our shoulders and just buy them because they were in the right gear box but our buddies in Kileen (Team #647 the CyberWolves) saved our butts and double-checked with FIRST and made sure we got the right motors.

And boy are we glad they did. While programming the robot arm one of the variables in the code wasn't quite right and we got to smell the sweet smell of a thermo cutoff switch burning off its factory coating. Fortunately for us once it cooled down the motor was as good as new! Having the 9012 versus the 9003 was a lifesaver!

-Danny

Re: Attention Robot Inspectors:
 

Ok so I've been doing a little digging and found this in the FIRST Forums, it looks like FIRST is aware of the issue and has made some type of arrangement to correct it. http://forums.usfirst.org/showthread.php?t=3916
this was posted at the beginning of the month so I am not sure if this was just for build season or not but it's worth checking into. Hope it helps.

Re: Attention Robot Inspectors:
 

If by making arrangements to correct it you mean ignoring emails (at least in my personal experience), then yes.

Re: Attention Robot Inspectors:
 

FYI,
The current limit in this motor trips at well below stall current. In test we found the motor trips at about 24 amps. Since it is a thermal trip, each successive trip causes a much longer recovery.

Re: FP 9003 vs 9012 (was Attention Robot Inspectors:)
 

We also got 9003s at the manchester kickoff. It took something to the tune of 5 weeks to get a response out of FIRST, but they did finally respond saying they were sending us the correct motors, which means we have to take apart the whole assembly at Boston to replace our motors. Not a fun situation.

Re: FP 9003 vs 9012 (was Attention Robot Inspectors:)
 

Well, hopefully we were the only team that got bit by this mistake. We used 9003s in our prototype design, not thinking there was a difference. The design worked great, and we were lifting 160 pound bots on our ramps with no problems in our lab. Thursday morning at the Phoenix Regional, a student reminded us we had to use the 9012s so we made a quick swap out on the bot, thinking there would be no big deal. After the first few matches of not being able to lift anyone we were going nuts trying to figure out what happened..?? After two days of trying to figure it out, we realized that the current limiter was cutting us off on any bot over about 100 pounds. That being said, our primary design/plan of lifting 2 bots per match securing 60 points, got us 0 bots per match. We were dead in the water and useless at the Phoenix regional because of it. Just a valuable lesson for anyone trying to lift bots or making any last minute switches on these motors.

~Shea~