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The rule says that the minibot can never expand itself beyond the 12" cube parameter. The motors are not strong enough to wind or extend the surgical tubing. We were thinkg of sending a metal plate up the pole but the 12" cube rule wont allow us to do that.
I would like to know if we are right about the 12" cube rule, and if we are right, i dont think we can do much with the minibot.
Zuelu562
19-01-2011, 18:19
Recent Team updates and official Q&A Responses say that the minibot may NEVER leave a 12"X12"X12" cube in dimensions.
Back to the ol' drawing board!
SirTasty
19-01-2011, 18:33
The rule says that the minibot can never expand itself beyond the 12" cube parameter. The motors are not strong enough to wind or extend the surgical tubing. We were thinkg of sending a metal plate up the pole but the 12" cube rule wont allow us to do that.
I would like to know if we are right about the 12" cube rule, and if we are right, i dont think we can do much with the minibot.
FIRST doesn't want super crazy creative gamebreaking minibots, hence the <G19> update. Don't worry, there really isn't a lot of room for innovation here. The real game is not in the minibots, but in the way they are deployed.
Zuelu562
19-01-2011, 18:36
FIRST doesn't want super crazy creative gamebreaking minibots, hence the <G19> update. Don't worry, there really isn't a lot of room for innovation here. The real game is not in the minibots, but in the way they are deployed.
Exactly my sentiments. Fine tuning minibots and deployment is going to be the key to those bonuses.
Al Skierkiewicz
20-01-2011, 12:02
konk,
Remember that each minibot shown during kickoff was built with the same rules in mind.
Sirtasty, I prefer to think that the GDC is making us think harder not that "FIRST doesn't want super crazy creative gamebreaking minibots".
FIRST doesn't want super crazy creative gamebreaking minibots, hence the <G19> update. Don't worry, there really isn't a lot of room for innovation here. The real game is not in the minibots, but in the way they are deployed.
I think it's more like FIRST knows how creative we can be and wants to prevent use from making potential dangerous projectile minibots.
I think it's more like FIRST knows how creative we can be and wants to prevent use from making potential dangerous projectile minibots.
I think they want to make ensure the structural integrity of their top plates.
I think they want to make ensure the structural integrity of their top plates.
I think the next Team Update may well limit the max force expended on the top plates! :)
Jon Stratis
20-01-2011, 12:57
FIRST doesn't want super crazy creative gamebreaking minibots, hence the <G19> update. Don't worry, there really isn't a lot of room for innovation here. The real game is not in the minibots, but in the way they are deployed.
I would say FIRST is trying to force teams to actually be creative with the minibot through the restrictions. If we could just throw the bots up there, that would be the dominating strategy... and based on CD threads, there would be a lot of bots designed that way. By providing strict limits like FIRST has done, it forces you to be creative in order to win. To actually design something better than everyone else, instead of simply having the most tension and the quickest release on your slingshot.
DonRotolo
20-01-2011, 21:02
As in life, the more restrictive the rules, the more creative the 'best' solution will be. Even though the minibot cannot exceed a 1 foot cubical box, teams should be thinking outside that box :D
pfreivald
20-01-2011, 21:16
We have a few designs that are really quite different. After being convinced in my own mind that nothing would be more efficient than a simple wheel, I have found that I might well be wrong on that score!
Saber Robotics
20-01-2011, 21:51
Sorry this is off topic but I could not find a better place to post this. Our fuse in our FTC battery pack "broke". We attempted to charge and then the battery pack didnt work. Here is a picture of the fuse that we think is the problem.
http://saberrobotics.org/images/FTC%20battery.JPG
Could anyone tell us where we can get a new one or exactly what the name of it is?
klmx30302
20-01-2011, 21:57
The fuse is a 20 amp mini blade fuse. You can get them at most/all automotive stores. We have blown about 5-10 fuses (so far).
pfreivald
20-01-2011, 22:00
The good news is that not only are those fuses really easy to find (via automotive parts stores as klmx30302 said), they're also really cheap.
Buy lots, and keep them handy!
Saber Robotics
21-01-2011, 12:10
Thanks very much
Brandon Holley
21-01-2011, 12:15
Buy lots, and keep them handy!
Very good advice, I highly recommend everyone follows it.
-Brando
What do you think is causing the fuses to blow?
Jon Stratis
21-01-2011, 12:55
What do you think is causing the fuses to blow?
Simple answer? You're pulling too much current through them!
The problem with fuses like this is that it doesn't take much to blow them. Stall your motors, and they'll blow pretty quickly. There's a similar fuse in each Spike, and those can be blown just from the startup current from the KoP compressor! Because of this, a few years ago FIRST started allowing teams to replace those with the 20A snap action breakers from the power distribution board (Although since we aren't doing pneumatics, I haven't read that section of the manual and can't say for certain it's allowed this year as well). It would be pretty nice if FIRST allowed a similar modification to this component, although I have to stress - unless allowed through a team update or a Q&A, your stuck using the fuses.
Jared Russell
21-01-2011, 14:52
The mounting clamps for the Tetrix motors were the cause of nearly all of our blown fuses thus far - the motors will rotate in their housings over time, which has caused gears on the output shaft to mesh too tightly, stalling the motors.
Just one thing to keep an eye on.
Thank you everybody,
I was looking at the list of what we can use on the minibot, and I found out that we can use aluminium sheets.
So are we allowed to make stuff out out aluminium sheets?
Thank you :)
klmx30302
21-01-2011, 18:40
Our team thinks the cause is not starting the motors before the minibot is on the poll. we think that the startup load is increased and the fuse blows, we were going to test this tonight but we have no school so no meeting.
Polaris395
21-01-2011, 18:49
Thank you everybody,
I was looking at the list of what we can use on the minibot, and I found out that we can use aluminium sheets.
So are we allowed to make stuff out out aluminium sheets?
Thank you :)
Based on the validity of the first statement: Yes, you may.
The mounting clamps for the Tetrix motors were the cause of nearly all of our blown fuses thus far - the motors will rotate in their housings over time, which has caused gears on the output shaft to mesh too tightly, stalling the motors.
Just one thing to keep an eye on.
Are you clamping the motor or the gearbox? The supplied clamp fits best over the gearbox which is slightly larger diameter. If you are clamping the motor casing, I wouldn't predict a good outcome to that situation.
Fuses can be blown by stalling the motor, causing over-current. Also easy to blow fuses if you are using alligator clip connections to the motor supply tabs. Solder some heavy gauge stranded wire in two different lengths to those tabs and shrink some insulation over them. Then make your motor connections to those wires at the offset other ends. This will reduce the number of accidental shorts and save you a bunch of fuses.
boomergeek
21-01-2011, 19:22
Are you clamping the motor or the gearbox? The supplied clamp fits best over the gearbox which is slightly larger diameter. If you are clamping the motor casing, I wouldn't predict a good outcome to that situation.
Fuses can be blown by stalling the motor, causing over-current. Also easy to blow fuses if you are using alligator clip connections to the motor supply tabs. Solder some heavy gauge stranded wire in two different lengths to those tabs and shrink some insulation over them. Then make your motor connections to those wires at the offset other ends. This will reduce the number of accidental shorts and save you a bunch of fuses.
I did not see solder on the allowed list of parts for the minibot. (Nor did I see simple electicial connectors that are equivalent but not exactly TETRIX parts).
Cannibalizing solder off hundreds of TETRIX pieces would probably be deemed legal based on the current rules.;)
Was anyone seen a GDC ruling on solder on the minibot?
Al Skierkiewicz
22-01-2011, 08:23
The minibot rules change the robot rules for specific minibot items. Solder is allowed on the main robot and since it is not excluded in the minibot rules is allowed.
Mr_D_Mentor
27-01-2011, 21:56
This is good news. Since we already soldered wires to the motor, I was starting to think we would have to remove all the solder, which would be very difficult.
Are you clamping the motor or the gearbox? The supplied clamp fits best over the gearbox which is slightly larger diameter. If you are clamping the motor casing, I wouldn't predict a good outcome to that situation.
Fuses can be blown by stalling the motor, causing over-current. Also easy to blow fuses if you are using alligator clip connections to the motor supply tabs. Solder some heavy gauge stranded wire in two different lengths to those tabs and shrink some insulation over them. Then make your motor connections to those wires at the offset other ends. This will reduce the number of accidental shorts and save you a bunch of fuses.
You can over tighten the clamp on the gearbox housing also...trust me, my new FTC team found that out the hard way.::ouch::
As in life, the more restrictive the rules, the more creative the 'best' solution will be. Even though the minibot cannot exceed a 1 foot cubical box, teams should be thinking outside that box :D
OR INSIDE THE BOX.
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