How to control the minibot?

[dotbran]

Are basic electrical components allowed for use on the minibot, like capacitors and photoresistors, to trigger and disable the robot?

[pfreivald]

Originally Posted by dotbran

Are basic electrical components allowed for use on the minibot, like capacitors and photoresistors, to trigger and disable the robot?

I don't see them on the list of allowable parts... (Indeed, I'd love it if we could use *regular* resistors...)

[DarrinMunter]

Since a relay is like a switch are we allowed to use one in a custom circuit?
Not talking about a Spike relay, but a normal one.

The student that is in charge of the FIRST Q&A didn't show up tonight.

[Al Skierkiewicz]

Guys the list of allowables on the minibot is very specific. Relays are not on the list, components like resistors and photoe sensors are not on the list, except those that are Tetrix parts when used with the NXT that are on the list here...http://www.usfirst.org/uploadedFiles...ix%20Parts.pdf

I have to ask, what would you use the resistor for?

[pfreivald]

...to make it come back down nice and slowly under drive without a controller.

[Al Skierkiewicz]

Patrick, It will do that if you remove power from the motor and short the leads of the motor. This is the technique that is in use when you select "brake" mode on a speed controller.

[pfreivald]

Originally Posted by Al Skierkiewicz

Patrick, It will do that if you remove power from the motor and short the leads of the motor. This is the technique that is in use when you select "brake" mode on a speed controller.

Of course, of course, and as a physics teacher I already know that... But it's only true if your MINIBOT back-drives down the pole in the first place -- which ours currently does not. Thus, shorting the motor leads will result in it continuing to not come down at all, instead of coming down slowly.

It's all good. Just more stuff for the kids to figure out!

[chris janney]

Originally Posted by pfreivald

...to make it come back down nice and slowly under drive without a controller.

I don't think minibots are going to come down nice and easy. i would build one to with stand a fall from 122 inches. take a pole vaulters advice, hitting the ground will not be fun. ten-and-a-half feet, you would want a nice thick pad to fall on. build it so it can take the fall, and be ready to rewire if need be.