2011 Minibot electronics

[peter1626]

I am a little confused by R92 it says that you are allowed 1 12v battery pack and 1 NXT controller, but the NXT requires 6 AA batteries thats 9 volts, so does this mean we are allowed to use both the NXT WITH its standard battery in addition to a 12V FTC Battery pack or do we have to somehow modify the NXT?

[JohnHorton]

Originally Posted by peter1626

I am a little confused by R92 it says that you are allowed 1 12v battery pack and 1 NXT controller, but the NXT requires 6 AA batteries thats 9 volts, so does this mean we are allowed to use both the NXT WITH its standard battery in addition to a 12V FTC Battery pack or do we have to somehow modify the NXT?

Well, a 9v regulator would work, but that isn't listed on the components allowed.I find it kind of odd they don't allow basic electronics (resistors, caps, etc.) for the minibot. Correct me if I'm wrong.

I think a simple DC loop of Battery - Lightswitch - motor(s) - back again might be the best, as far as electronics go.

[Al Skierkiewicz]

Since R92 is a list of the permitted parts and the NXT requires the AA battery pack, I would expect that those batteries would be legal. Since the only motors allowed are Tetrix motors that cannot be driven directly by the NXT, the NXT battery will not provide power to drive motors. (See above post of R92)

[Jon236]

Maybe it's time to teach the students how to make a speed controller (1/2 H-bridge....since all we want is a one-way trip (powered, at least!))

[ATannahill]

Originally Posted by Jon236

Maybe it's time to teach the students how to make a speed controller (1/2 H-bridge....since all we want is a one-way trip (powered, at least!))

You can have your one way trip, I don't want the field reset team to pull out a shotgun to get our minibot down.

[Jon236]

Originally Posted by rtfgnow

You can have your one way trip, I don't want the field reset team to pull out a shotgun to get our minibot down.

I meant one-way powered......after contact with the sensor, the 1/2 bridge is turned 'off' and the mini coasts downward.

[EricVanWyk]

Is it legal to have a tether wire between the robot and the minibot? Wires are allowed in R92X, but I'm not clear whether or not the sizing box in R91 precludes them.

My apologies if this has been discussed elsewhere, it is impossible to follow all these threads!

[Jon236]

Originally Posted by EricVanWyk

Is it legal to have a tether wire between the robot and the minibot? Wires are allowed in R92X, but I'm not clear whether or not the sizing box in R91 precludes them.

While only the GDC can say for sure, I am assuming that tethers would be illegal because of the 12x12x12 sizing box requirement and by the usual no-entanglement rules.

[PAR_WIG1350]

Originally Posted by Jon236

While only the GDC can say for sure, I am assuming that tethers would be illegal because of the 12x12x12 sizing box requirement and by the usual no-entanglement rules.

Oh dear, tape measures

[Al Skierkiewicz]

<R92> The following items are the only permitted materials for use on the MINIBOTS:
A. TETRIX components,
B. no more than two motors (PN W739083),
C. exactly one 12V rechargeable NiMH battery pack identical to those supplied in the FTC kit of parts (PN W739057)
D. No more than one HiTechnic DC motor controllers,
E. No more than one NXT controller with the Bluetooth functionality disabled,

The motor controllers are driven from the NXT outputs.

[Bruceb]

Again what do you all think. R92 d sayes exactly 1 battery pack. Do you think that means we HAVE TO HAVE a battery??
Bruce

[Jon236]

Originally Posted by Bruceb

Again what do you all think. R92 d sayes exactly 1 battery pack. Do you think that means we HAVE TO HAVE a battery??
Bruce

Without specifying a required wiring schematic, I think that IF we want a battery, it has to be the battery they specify. But I don't read anywhere that we HAVE to have a battery.

GDC just want to make our brains hurt!

[Al Skierkiewicz]

Erik,
From Section 1
MINIBOT – an autonomous vehicle designed and built to perform specific tasks when competing in the 2011 competition LogoMotion. The MINIBOT must obviously follow a design approach intended to play the 2011 FRC END GAME and must be compliant with all MINIBOT rules defined in Section 3.4.14.

And from Section 1.5
The match ends with robots deploying minibots, small electro-mechanical assemblies that are independent of the host robot, onto vertical poles.

I read those two references as not tethered. The Q&A will be the only place to get an official answer on this question.

[EricVanWyk]

Originally Posted by Al Skierkiewicz

Eric,
...
I read those two references as not tethered. The Q&A will be the only place to get an official answer on this question.

Thanks Al

After reading those sections, I agree with your interpretation.

[bookman101]

Your minibot has to be an electromechanical devises as stated in the logomotion summary, and your could possibly use a tether as long as you can assure that it will never touch the pole. The tether would be considered part of the hostbot by my understanding and would violate the rule of the host bot touching above the deployment line.