Van Door Motor Problem
 

OK so heres what happened....we designed and built our arm going by the specs FIRST gave us on the Taigene Van door motor and it was supposed to run at a free speed of 75 RPMs but once we hooked the arm up and tested it for the first time it was going really slow. so we made a mark on the motor shaft and timed it and it only was running at 50 RPMs under no load....has anyone else had this problem? or if anyone has a comment on this? we are kind of stumped

p.s. we tested one of the previous years van door motors and it ran at almost 80 RPMs.

Re: Van Door Motor Problem
 

how confident are you about your electrical connections? resistance will affect a bit. and how full were your batteries?

Re: Van Door Motor Problem
 

the batteries were fully charged...12.7 under load...and it was connected right to the battery soo there wasn't any resistance

Re: Van Door Motor Problem
 

If you have it hooked up into a drivetrain of some sort, there is no way it should be running at free speed even if there is no load on the arm, slider, winch, whatever. Chains, gears, shafts create friction that will slow it down when you think its under "no load"

Re: Van Door Motor Problem
 

no the tranny on the arm doesnt cause enough friction to slow it down at all...#1 your talking a 33% decrease in speed from 3 gears and chain....and #2 we tested it alone w/o anything also and it ran the same speed of 50 RPMs

Re: Van Door Motor Problem
 

Can someone just duplicate this test on a new Taigene and post your results here?
OR
Is there a known fault in the no load speed on the Taigene spec sheet??

Re: Van Door Motor Problem
 

K,
Since it is a new motor, the lubricant hasn't really had a chance to distribute itself inside the case. Run it for a while and I think you will find it will speed up. Due to the odd shape of this motor, they are often dropped or set down hard on the shaft (threaded end) which causes a bent shaft or a crack on the back side of the gearbox, this could cause misalignment of the gears and results in slow free speed. If you find a small crack, there is no coming back from this failure and it will only get worse with time.

Re: Van Door Motor Problem
 

188 tested the van door's free speed, and also got around 50 rpm. We didn't run it long enough for any significant wear on the worm gear or lubricant redistribution to take place. Older van door motors did indeed perform differently, but like Al said, it might be due to being a brand new motor, not yet broken in.

Maybe someone could lightly load a motor (known to run at 50 rpm) for a half-hour, and then re-measure the free speed, to see if any change took place.

Re: Van Door Motor Problem
 

its worth a try i guess

Re: Van Door Motor Problem
 

ya we ran the motor for over 30 min and it didnt really do much for speed....if anyone else has had the slow motor problem please post....

Re: Van Door Motor Problem
 

Our 2005 Van Door motor also runs ~50rpm free speed.

[edit]
I looked up the history of the Taigene spec.
See this thread http://www.chiefdelphi.com/forums/sh...hlight=taigene
In particular Joe Johnson's posts on the revised Taigene specs.

Re: Van Door Motor Problem
 

Ok, lets say that the speed of the motors doesn't get better, what would this mean? Are the specs wrong? or is there a problem with the motor? would they be less reliable?

Re: Van Door Motor Problem
 

Specs would be wrong. The results have been duplicated (or I suppose, the whole batch donated to FIRST could be defective, but that seems unlikely).

Re: Van Door Motor Problem
 

okie... some work was required in finding this out (not really) but its ok. its all for you guys.

The old motors are 75 rpm. The new ones look the same. And have a free rpm of 50. Life sucks. But.. the good part is that they have the same power. Torque is greater in the new motor, they equal out to roughly the same power. So... all it does is force all you people using it to redesign. Great...

Re: Van Door Motor Problem
 

so they didnt edit the spec then is what your saying? thats great... :ahh:

Re: Van Door Motor Problem
 

Ok...

People are starting to panic because it is week 5 now and such motor problems are not appreciated. Anyway. On to the point.

I have been looking around all over the place to find accurate van door specs. I have not found any. All of them are still the same old ones. Which are very wrong. The information in my first post is correct, it was actually measured. However, all we measured was theoretical power and free speed. So.. has anyone measured the actual stall torque, max efficiency, etc? I have lost my confidence in spec sheets.

Re: Van Door Motor Problem
 

I asked a question about this on the FIRST Q&A System and it was deleted... who knows what FIRST is doing.

Re: Van Door Motor Problem
 

So does anyone have the stall torque numbers for the new vandoor? Without it, there is no equation, and without the equation there is no redesign...

Re: Van Door Motor Problem
 

Apparently.. :sigh: I have found something that opens an even more frustrating question to this problem.

http://www2.usfirst.org/2005comp/Specs/Taigene_PSD.pdf

shows the spec for motor number:










edit: Overall pic of the thumbnail below is found here.
http://www.team237.com/gallery/Build...DR_2250_Medium

Re: Van Door Motor Problem
 

I did an RPM check on our kit van motor and it ran 78rpm

Re: Van Door Motor Problem
 

Did the sticker on the motor call out the same part number as the one I attached a thumbnail of, or the spec sheet motor? Cause they seem to be two different models, and/or part numbers. :(

Re: Van Door Motor Problem
 

Sorry I didn't check it, but I will tommorow and let you know

Re: Van Door Motor Problem
 

I opened ours up. This year’s has a ~104 tooth worm gear (as best as I can count without complete disassembly) and a worm with two threads for a 52:1 reduction. A prior year’s (with a 75rpm free speed) had a 65 tooth worm gear and a single thread worm. So the speed reduction is not due to the gearing.

Re: Van Door Motor Problem
 

Ok. What was the part number on the sticker of yours?

Re: Van Door Motor Problem
 

Tested ours, this years 51 rpm battery voltage 12.4, Last years 78 same battery voltage. Both will back drive with a wrench, BTW no speed difference on this years motor forward or backward. Sticker on the motor is similar to one further up in the post. Didn't check the numbers yet. Will do and and edit this post. Ours is the rev 02 and part number 16644829 the same as the pic posted by Elgin Clock post #19
Tom Cooper 1227

Re: Van Door Motor Problem
 

Wow, our motor number (16640238 rev 4) is different from both the spec sheet and the thumbnail above. Today, we did a whole lot of testing with textbooks and a multimeter on it, and we'll come up with a power curve for this given model, and post it up if anyone cares/is willing to believe our Überghetto experiments. What's really annoying is that there are 4 different models of the "same" motor mentioned in this thread only... What does FIRST have to say on this variety?

Re: Van Door Motor Problem
 

Yeah............ ours was going slower than previous years motors have. i am not sure about the RPM's though.

Re: Van Door Motor Problem
 

My reply is a bit off, but...

HOW do you attch the shrift of the Van door to a gear or spock

Re: Van Door Motor Problem
 

We filed/drilled a tiny 'dent' into the shaft and tightened a setscrew into it. There are othe ways, too.

I didn't time our motor, but our arm was geared based on the specsheet and performing exactly as expected (time/torque wise).

Re: Van Door Motor Problem
 

We got a full 80 rpm from ours on a charged battery.

Re: Van Door Motor Problem
 

please keep unrelated topics out of this thread...thanks

Re: Van Door Motor Problem
 

ok well the people from FIRST finally got back to the Q and A question we posted about having 50RPM on the Taigene Van Door Motor and the answer was.....

Re: Van Door Motor Problem
 

But then the question was deleted off the system.. I don't get it.. :sigh:

Oh well, at least we got an answer.

Re: Van Door Motor Problem
 

Here's our model number. 50 rpm both directions @12.4v.

Re: Van Door Motor Problem
 

We all know that last year's van doors are basically the same, and have normal unscrewy rpms, the ones that everyone expected. My question is, are they legal to use on this years bot? And.. what if they are supposed to be the same part number? The motors would be identical then.

As for all the motor variaties... FIRST maybe wanted it to be that way. To give us a bunch of different motors. But... that doesnt sound very fair, does it? I might be going a bit to far.. but I think FIRST should replace all the wierd motors that we have with the normal ones like last years, at no expense to teams. I personally don't mind too much because we aren't screwed by this. We can still redesign and make out mechanisms... but what about teams that have made everything and can't make new parts? But hey.. just my opinion.

Re: Van Door Motor Problem
 

So far, in the absence of a ruling to the contrary, if an old-style Tiagene van door motor were shipped to any team this year, I'd tend to consider that motor fair game for all.

It's quite safe to assume that they don't want to do this. Like the F-Ps, they seem to have accidentally obtained a mixed lot, without correct specifications.

A point for the team forums, when they arrive, later in the year: let's make sure that any kit motor or significant component is accompanied by a model number and corresponding specification document, and that these are checked in advance for accuracy.

Re: Van Door Motor Problem
 

Has anyone found a resolution to this problem yet? I posted this just now:
Since it seems like all the other questions asked by other teams on this issue were deleted, I figured I would try again.

As the question states, we are seeing the same thing mentioned in this thread. Our van door motor has a different serial number than the specification document on the FIRST 2005 motor spec:
http://www2.usfirst.org/2005comp/Specs/Taigene_PSD.pdf

We have checked all of our wiring, and even run straight from 12.8V, and the motor will only spin a maximum of 52RPM!!! We had planned and designed around the specification of 76RPM, but now our lift is way too slow!!

We got frustrated and went to try last year's motor (bought from the FIRST garage sale). When we plugged that motor in it sparked like crazy. So we opened it up. The motor we bought had a cracked magnet!! So we went to switch the casing with the new motor so we could test the old motor, and decided to open them up. What we found disturbed us:
http://www.penfieldrobotics.com/test/doormotors.jpg
The one on the right is this years motor, the one on the left is last year's motor. While it is possible they made a drastic change in the gearing as seen to account for the motor, the gearing in the boxes seems to match our 52rpm/76rpm issue. And it just seems funny that the motor was labeled "bad" when we got it.

Does anyone know if last year's motor is legal?? It would seem so since that is what the specification document references.

HELP!!

Re: Van Door Motor Problem
 

We tested our motor speeds and got 80 rpm's for both this years and last years motors.
As to using last years, how could they tell if you do? They look the exact same. ;)

Re: Van Door Motor Problem
 

well first of all gracious professionalism will tell you not to do that but there are also differences in the appearance of last years motor vs this years

last year had a completely round casing around the motor windings , and output shaft with a flat then a space and then treads, as well as a waffle pattern on the back of the gear casing


this year has a more square casing, a different flat/thread pattern on the shaft, a flat back on the gear case, and a different hole pattern

any inspector with any experience should be able to tell the difference almost instantaneously

Re: Van Door Motor Problem
 

I do not have the part number for our Vandoor motor, but a quick time based off a charged battery gave ~80 RPM in one direction, about 5-10 rpm slower in the other. This was a really quick and dirty count over 15 seconds, so take it with a grain of salt. Still, it sounds like we have a 'fast' motor.

-Andy A.

Re: Van Door Motor Problem
 

Yes, but last year's motor is the serial number that FIRST Spec'd in their own documentation (and the KOP checklist does NOT give a serial number) so it would seem as if last year's motor is legal to use. Question is, did any of the teams actually get the S/N 16638628 Motor??

Additionally if <R20> is read, the part "[Last year's motors] may be used as direct one-to-one SPARE PARTS for those provided if the provided part fails or is damaged." I would say the 52RPM is a failed part (hence the "bad" sticker, perhaps?!?!). It does continue to say though "They may only be used if they are identical to the part being replaced," and continues to suggest that only the Fischer price motors fall in this category.

From what I have been told of this van door motor, it was intended to be a factory replacement for last year's motor. However, it does not perform that way. My gut feeling is that if other teams have a motor from the kit that spins almost 80RPM we are at a huge disadvantage sitting with a motor that only spins 52RPM.

I hope to hear from FIRST, other than that we can swap at competition. If we have to swap at competition, we run the risk of throwing portions of our automode off, due to the inablity to test them, and we have to go custom machine our shaft again.

Re: Van Door Motor Problem
 

I wish I had seen this sooner. We, too, have a Taigene 16644829 (although it's a Rev01) van door motor. We haven't tested it for speed, but am I to assume that this is a 50-52RPM motor instead of the specified 74RPM? And that's at 12.4V? Does anyone have any specs on this particular motor? We're trying to use it in conjunction with a Nippon Denso Window Motor to lift our arm, so it's important that we know how to match them for speed and torque. But then, if we lose this motor, what will we have to replace it with? A 50RPM or 74RPM? Thanks.

Re: Van Door Motor Problem
 

yea.. has this been asked to FIRST Q&A ?

i think this might make things very unfair/biased as some teams will have diffent motor specs././ and the purpose this year was that all teams have exact same motors, and none that are not supplied in KoP.. . . so.. . yea.. idk our speed now that our motors is shiped off.. but i am currently trying to find a second one for our second robot (practice) and its being a really big beyotch.. . if u have any info where email me short1@gmail.com