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  #31  
Old 05-04-2012, 12:01 AM
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Jij Jij is offline
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Re: Team 1107B Taiwan Drive (credits to 4194B)

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Originally Posted by Vex Mundi View Post
Yeah I remember the robot, I just wasn't sure where you guys got the idea. It was very similar looking to your Clean Sweep robot, for example, so I didn't know whether you had just decided to try that again.
We wanted to try the intake that we had on the Clean Sweep robot (which is still in tact, btw ), but we had been testing other ideas out. However, our other ideas didn't work so well so we changed back to the top rollers, since we had seen the similar ones on 24c's robot work well.

~George
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  #32  
Old 05-04-2012, 12:05 AM
BluethunderLegacy BluethunderLegacy is offline
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Re: Team 1107B Taiwan Drive (credits to 4194B)

What does the back drive lock do? Is that really nscessary? (Its driving around well) Lastly murdomeek, are the answers ive gotten correct, from my previous posts
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  #33  
Old 05-04-2012, 12:08 AM
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murdomeek murdomeek is offline
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Re: Team 1107B Taiwan Drive (credits to 4194B)

if you watch the video again, when i hold the wheel with my hand, the motors are still spinning
that means in a real match, if you try to push someone, you wont move and your motors will still be spinning (wasted energy not transferred to your drive)
the "lock" will make sure all the energy gets transferred (and therefore you will push them)

and yes, the others that answered you are correct
they are experts on planetary systems as well!
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  #34  
Old 05-04-2012, 12:10 AM
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Re: Team 1107B Taiwan Drive (credits to 4194B)

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Originally Posted by murdomeek View Post
here is a video on the backdriving lock:
all i did was jam a inset in the gears to lock them
http://www.youtube.com/watch?v=Y1idc...ature=youtu.be

how on earth are we suppose to get ANY sort of controllable lock in that position?!
not only does it have to jam into the gears, it also must rotate along with the module as well...
It's looking better every day.

So instead of locking the planet carrier to the ring gear inside the planetary gear set, try locking the two inputs together.
The ring gear should be locked so it turns with the planet carrier. I would suggest pushing a gear in using pneumatics to couple the two motors' power.
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Last edited by dontworryaboutit; 05-04-2012 at 04:44 PM.
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  #35  
Old 05-04-2012, 06:22 AM
StephenDsDude StephenDsDude is offline
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Re: Team 1107B Taiwan Drive (credits to 4194B)

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Originally Posted by dontworryaboutit View Post
Quote:
Originally Posted by murdomeek View Post
how on earth are we suppose to get ANY sort of controllable lock in that position?!
not only does it have to jam into the gears, it also must rotate along with the module as well...
It's looking better every day.

So instead of locking the planet carrier to the ring gear inside the planetary gear set, try locking the two inputs together instead.
The ring gear should be locked so it turns with the planet carrier. I would suggest pushing a gear in using pneumatics to couple the two motors' power.
Instead of locking the chain on the planetary system, add a gear to the sprocket that is directly driven by the motor and use a locked gear (like the one on the differential system) on this to lock your chain.

I would also suggest adding some sort of rollers to the chain to make the chain around the planetary gear system circular (like the image I posted). It makes the rotation of the carrier gear much smoother with a [almost-] uniform tense chain.
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  #36  
Old 05-04-2012, 04:48 PM
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Re: Team 1107B Taiwan Drive (credits to 4194B)

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Originally Posted by StephenDsDude View Post
Instead of locking the chain on the planetary system, add a gear to the sprocket that is directly driven by the motor and use a locked gear (like the one on the differential system) on this to lock your chain.

I would also suggest adding some sort of rollers to the chain to make the chain around the planetary gear system circular (like the image I posted). It makes the rotation of the carrier gear much smoother with a [almost-] uniform tense chain.
You still want the sprocket and chain to turn, so I'm not sure what you're describing? A locked gear on my differential system works because I have separate differentials for high-speed and high-torque (so locking the one you don't want will work). However in the planetary transmission you are using the same chain and gear combination to power both high-speed and high-torque.
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  #37  
Old 05-04-2012, 05:44 PM
StephenDsDude StephenDsDude is offline
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Re: Team 1107B Taiwan Drive (credits to 4194B)

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Originally Posted by dontworryaboutit View Post
You still want the sprocket and chain to turn, so I'm not sure what you're describing? A locked gear on my differential system works because I have separate differentials for high-speed and high-torque (so locking the one you don't want will work). However in the planetary transmission you are using the same chain and gear combination to power both high-speed and high-torque.
I saw in the youtube video murdomeek attempted to lock the chain with a hexkey through the planetary gear. If you attached a gear to the sprocket driving the chain from the motor, and then had a locked gear attached to a pneumatic piston or motor or something, that could lock the chain system from backdriving very easily.
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  #38  
Old 05-04-2012, 06:05 PM
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Re: Team 1107B Taiwan Drive (credits to 4194B)

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Originally Posted by StephenDsDude View Post
I saw in the youtube video murdomeek attempted to lock the chain with a hexkey through the planetary gear. If you attached a gear to the sprocket driving the chain from the motor, and then had a locked gear attached to a pneumatic piston or motor or something, that could lock the chain system from backdriving very easily.
What murdomeek did in the video was lock the planetary gears to the sun gear, which effectively locks the planet carrier to the ring gear. Note how the ring gear (the chain) kept moving in his video? If you lock the ring gear (the chain and sprockets) from moving entirely (like I think you are suggesting), you have half the torque going into the planetary gear set and twice the speed coming out, so you've actually got 1/4 the torque of what you want
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  #39  
Old 05-04-2012, 06:08 PM
StephenDsDude StephenDsDude is offline
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Re: Team 1107B Taiwan Drive (credits to 4194B)

Quote:
Originally Posted by dontworryaboutit View Post
What murdomeek did in the video was lock the planetary gears to the sun gear, which effectively locks the planet carrier to the ring gear. Note how the ring gear (the chain) kept moving in his video? If you lock the ring gear (the chain and sprockets) from moving entirely (like I think you are suggesting), you have half the torque going into the planetary gear set and twice the speed coming out, so you've actually got 1/4 the torque of what you want
Ah; I misunderstood then, my bad. I see it now.
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  #40  
Old 05-04-2012, 06:14 PM
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Re: Team 1107B Taiwan Drive (credits to 4194B)

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Originally Posted by StephenDsDude View Post
Ah; I misunderstood then, my bad. I see it now.
No problem.
The backdriving rig is weird (4194 didn't even find a way to do it).
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