Circular to Linear Task

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Xenarian
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Re: Circular to Linear Task

Post by Xenarian »

I'm just using an electric (non-geared!) motor to wind up some string and raise a mass to hit a switch. That works, I guess. I'm not using any screws or gears, just plain old electric potential.
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Re: Circular to Linear Task

Post by yousmellchinese123 »

Don't Motors have gears inside of them, which would make motors unusable for this task?

Also, did you guys interpret the rules as converting the circular to linear motion of the same object?
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Re: Circular to Linear Task

Post by Primate »

yousmellchinese123 wrote:Don't Motors have gears inside of them, which would make motors unusable for this task?

Also, did you guys interpret the rules as converting the circular to linear motion of the same object?
As far as I know, most standard brushed DC motors contain no internal gearing. (Take a look at this picture.) You'll find that most geared motors have an external gearbox, which is pretty obvious.

And no, I think converting one object's circular motion to another object's linear motion is perfectly valid.
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Re: Circular to Linear Task

Post by yousmellchinese123 »

Primate wrote:
yousmellchinese123 wrote:Don't Motors have gears inside of them, which would make motors unusable for this task?

Also, did you guys interpret the rules as converting the circular to linear motion of the same object?
As far as I know, most standard brushed DC motors contain no internal gearing. (Take a look at this picture.) You'll find that most geared motors have an external gearbox, which is pretty obvious.

And no, I think converting one object's circular motion to another object's linear motion is perfectly valid.
That just made this task easier for me (:
Thanks for all the clarifications!
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Re: Circular to Linear Task

Post by Dark Sabre »

Primate wrote:As far as I know, most standard brushed DC motors contain no internal gearing. (Take a look at this picture.) You'll find that most geared motors have an external gearbox, which is pretty obvious.
Yeah, plenty of little DC motors have no gearing. Those that do are not always as obvious as that though.

This is a pretty standard gearhead motor:
Image
The gears are not visible, as they are housed in the front section.

It can be even harder to tell if the whole motor is enclosed.
For example, this Lego motor is ungeared:
Image
But this Lego motor is geared:
Image

If there is significant gearing you can tell simply by the fact that the motor is super slow. That top Lego motor spins at 4100 RPM. The bottom one spins at 340 RPM.

Even if you can't see whether there are gears or not, you should be able to tell by how fast it spins or how easy it is to turn the axle. If there are cooling vents in the back, you can also compare how many times you turn the axle to how many times the rotor spins.
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Re: Circular to Linear Task

Post by Primate »

Dark, are you planning to check if the motors devices use for said task are geared when you judge? Not that I'm planning to be super sneaky by using a geared motor (my winch works just fine), I'm just curious if teams will be penalized for using a black box that unintentionally contained gears. Either way, I have a feeling most event coordinators aren't as well versed in geared DC motors as you are. :P
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Re: Circular to Linear Task

Post by Dark Sabre »

Heh, since you have me thinking about this :?

I don't think it shouldn't matter if you are using a geared motor or not. You can just claim that the circular motion you are converting is the motion of the final axle. As long as you are not using gears (or screws) to actually convert between circular and linear, you should be fine.

Like the flowchart for a gearmotor lifting a weight on a string would look like this:

Electricity --> Circular --> Circular --> Circular --> Circular --> Circular --> Circular --> Linear

The task is only that last step, so it shouldn't matter if there are gears in the previous Circular --> Circular steps...the machine itself is allowed to have gears. That's my vote anyway. So I guess you can consider my previous post just informational on the appearance of gearmotors. :lol:

If the task were "Electrical --> Linear without gears" then we'd be back in the spot of wondering about gearmotors, but I'm probably going to be okay with them for this task, unless it gets clarified.

You are probably right that not every judge can spot a gear motor and you would have to be a crazy dude like me to know about those Lego motors. Every judge might not also think like I do or agree with my reasoning, so I'd recommend not using a gearmotor for this task unless someone gets an NSO clarification.
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Re: Circular to Linear Task

Post by Smok4hontas »

Would a ball rolling in a funnel then dropping straight done count in this task?
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Re: Circular to Linear Task

Post by penclspinner »

Smok4hontas wrote:Would a ball rolling in a funnel then dropping straight done count in this task?
Nopes.
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Re: Circular to Linear Task

Post by questionguy »

penclspinner wrote:
Smok4hontas wrote:Would a ball rolling in a funnel then dropping straight done count in this task?
Nopes.
Why not? Isn't the ball rolling in a circle (Circular motion) and then dropping into linear motion when the circular motion keeps it moving until it reaches the hole?

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