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Brett W
12-02-2002, 16:02
Why do no teams use the fisher price motors is there something wrong with them? Are they not reliable? Do they Break? Are there lots of teams who use them and just post no pictures? These answers would be greatly appreciated.

Kris Verdeyen
12-02-2002, 16:33
We used the FP motors on last year's robot to control a 2 DOF arm with a goal grabber on the end.

I think that they are good, moderately torquey motors that are fine as long as you're not planning on jarring the output really hard (i.e. running into a wall while using it on a drivetrain). The weak point is the plastic geartrain.

Although I have heard some venom concerning these motors. Let's see what some of the FP haters have to say. (Personally, I just think that they're jealous of Barbie's pink corvette)

jonathan lall
12-02-2002, 16:38
We've messed around with them fairly extensively, and they're not as horrible as you may have been led to believe. I've been told that even though they are torquey, they have parts that get damaged from wear. However, I suggest you post this question at firstcanadianregional.org, for a better answer.

AdamT
12-02-2002, 17:12
We are using them, they seem to work well when powering a spindle. It's hard to find a use for a motor designed to pull a 6 year old around when it's going on a 130 pound bot. Our use sems to work.

Elgin Clock
12-02-2002, 19:02
The transmission is just too bulky!

bmusser
12-02-2002, 19:18
We are using the FPs for drivetrain, but do not use the gear box. We come straight off the pinion gear that is pressed onto the motor shaft.

Ken Leung
12-02-2002, 19:41
The only down side about the F-P motor is that it tend to get hot really fast. Just look at the size of it, and think about how much surface area for heat to excape.

Besides, people tend to use the gearbox that came with the motor, and the plastic gears inside that gearbox tend to break under high load. Although, that won't happen too easily if you use it right.

A lot of team use the drill motor because they want to use the drill transmission to shift gears, which is pretty easy to do with a servo or pneumatics, whereas the fisher price will need a custom gear shifter.


Over all, Drills and Chiaphua's are still the most powerful motors in the collection. They can take the heat better than the FP, so why not let them be the toasters, and have the FP power a really strong arm or a high speed ball mechanism.

AAbrams
13-02-2002, 13:00
We used them last year on "SPYKE" our robot. You can see them on each of the sides. It had great pulling/pushing power. We would put people on the stretcher and take them up and down on the ramp last year. We would use them again this year but we want to be quicker. And we put some heat sinks on them with fan to keep them cool.

http://www.geocities.com/mhsfullmetaljackets/spyke.html

Tony
Captain 393

Wayne Doenges
13-02-2002, 14:20
We are using both of them this year. They will be operating our arm. One for raising/lowering the upper arm and one for raising/lowering the fore arm. We built custom made gear boxes. You can see the gear box in the Picture Gallery.

Wayne Doenges

ChrisH
13-02-2002, 15:14
We've used the FP's with gearbox every year since they were introduced. But we don't drive with them. They make a terriffic winch. Just mount the motor and run your cable. Of course the cabling is the hard part...

Don Taylor
14-02-2002, 00:09
We use them and like them, a lot of torque, decent transmission, etc.

Don
Team 343
Metal in Motion

roboticscom13
18-02-2002, 01:31
For the third year in a row, we are using the FP motors as drive motors, however this year we took off the custom gearbox and attached the end of the FP motors to the drill motor with a custom made cuppling design.

They are working as well as they did the other two years. The only thing is, is that like it was alreeady mentioned those motors do get hot quickly so if you do go with them do keep an eye on it.

Wetzel
26-02-2002, 03:46
We have one powering our superscooper!.

Perseus
13-03-2002, 15:54
We used the FIsher price motors(with two Bosh's) on our drive for our 1st two years. This year, we are using the two bosh's and the two chiaphus. I think the reason most teams are not using the FP motors is because the chiaphus are, in my opinion, better. They have better rpms, i believe 15000 (boshes are 20000). We do use the FP though; for our device that goes to the endzone

hemihead
13-03-2002, 22:07
FP motors are great...when used inside of their , er, design envelope.

Inside of the envelope (for Team 86) means elimninating the last stage of gear reduction, making a steel hub for the second-to-last stage gear, and taking off power at a really useful RPM with a stub shaft. The sped is very close to the drill motor output shaft in low range. We have successfully used a FP and Drill motor chained in parallel.....very nice, very easy, very simple.

Motors that overheat are most likely being run way below their peak power and efficiency points. Close to stall speed always means heat.

Our only FP failures have been due to 1.) Driving off the bridge full throttle and pancaking onto the rug....major impact load on plastic gears. 2.)practice driving on asphalt where the same thing happens...wheel slip then grab impact loads the gearsets.

Knock on my head, no failures to date on the gearbox in competition. Did have a motor fail (smoke and stink and everything at 2002 KSC ....no motor autopsy results yet....I think it was a defect or fluke....it wasn't really being beaten on that hard when it failed.

Adam Y.
28-03-2002, 17:37
Fisher Price motors are the ones with the plastic mount right. We used them on our robot his year but..... they're right we broke two of them. The plastic mounts are bad but our robot is strong with them. We never had any problems with breaking the gears but this makes me think. Most drill gearbox's have a plastic shifter gear in them. Do these drill motors do?:p